Copper protein structures
Neurotoxicity of a prion protein fragment
Hereditary ceruloplasmin deficiency with hemosiderosis
Cellular expression of ceruloplasmin in baboon and mouse lung
Copper in biological systems
Human ceruloplasmin gene
The blue oxidases: ascorbate oxidase, laccase and ceruloplasmin
Laccase -- homology to human ceruloplasmin
Aceruloplasminemia: disorder of iron metabolism
Hereditary ceruloplasmin deficiency with hemosiderosis
A nonsense mutation of the ceruloplasmin
DNA sequence of human pre-ceruloplasmin
The 5'-flanking region of ceruloplasmin gene
Ceruloplasmin resistance to proteolysis
Dolphin ceruloplasmin is proteolytically stable, aging different
Ceruloplasmin role in LDL oxidation by human monocytic cells
Cellular expression of ceruloplasmin in lung: anti-oxidant role
Modulation of the redox state of the copper sites of ceruloplasmin by chloride
Induction of ceruloplasmin in rat lung during hyperoxia
Ceruloplasmin oxidant stimulates growth
Ceruloplasmin tissue-specific gene expression during development.
Tissue-specific ceruloplasmin gene expression in the mammary gland
Ceruloplasmin relationships with the copper-albumin complex
Copper transport from ceruloplasmin: cellular uptake
Blood coagulation factor V is homologous to factor VIII and ceruloplasmin
Cartilage matrix glycoprotein is closely related to ceruloplasmin
Disulfidess and cysteines in human factor VIII
Nitrite reductase: a copper protein from Achromobacter cycloclastes

Copper protein structures

Adman ET 
Department of Biological Structure, University of Washington, Seattle 98115. 

Adv Protein Chem 42: 145-97 (1991)
The structural comparison of copper-containing proteins has provided a new dimension to the relationships suggested by sequence similarities. Ryden (1988) summarized the putative relationships, suggesting that a primordial single-domain cupredoxin evolved into the multidomain copper oxidases. The structures have revealed the fact that the differences reside primarily in insertions and deletions at junctions between secondary-structure elements. The mechanism of evolution (e.g., integration of new sequences into regions not essential to the Greek key fold) remains unknown.

Which of the properties of a cupredoxin fold are necessary for function is the subject of site-directed mutagenesis studies. Can two of the ligands be interchanged (e.g., the upstream histidine and partially answered by the multidomain copper oxidase structure. The Tyr-Cys-Thr sequence in plastocyanin (in which threonine is a member of the hydrogen-bonding pair) is homologous with the His-Cys-His sequence in ascorbate oxidase. In the latter electron transfer is believed to flow from the type I copper (bound by the cysteine) to the trinuclear cluster, probably via these histidine residues. Hence, one might infer that the tyrosine and threonine have some role in electron transfer.

Tyr-83 has been previously implicated in NMR studies as a primary site of electron transfer. The multi-copper protein structures have revealed interesting new features. The extra coppers are bound at domain interfaces, and can be single metals or the novel trinuclear cluster, depending on the availability of liganding histidines. A structural model of ceruloplasmin suggests that it will have at least two type I sites and, possibly, a third type I site such as stellacyanin (no methionine ligand), as well as a binding site for a trinuclear cluster.

The similarity of the sequences of N2O reductases and a domain of cytochrome oxidase to the sequences of proteins with known structures suggests that these, too, will have Greek key domains. Galactose oxidase and hemocyanin do not have Greek key folds in their functional domains, although each does have a Greek key domain. The need for a Greek key fold remains obscure. The apoproteins are clearly stable without metals; there are examples other than immunoglobulins of Greek key folds. So far copper seems to be found in a very limited subset of structures; zinc and iron have a much wider variety of environments in proteins. It may be that the copper-containing Greek key proteins represent a very small evolutionary niche.



Role of microglia and host prion protein in neurotoxicity of a prion protein fragment

Brown DR; Schmidt B; Kretzschmar HA 
Institut fur Neuropathologie, Universitat Gottingen, Germany. 

Nature 380: 345-7 (1996)
The prion protein PrPc is a glycoprotein of unknown function normally found in neurons and glia. It is involved in diseases such as bovine spongiform encephalopathy (BSE), scrapie and Creutzfeldt-Jakob disease. PrPSc, an altered isoform of PrPC that is associated with disease, shows greater protease resistance and is part of the infectious agent, the prion. Prion diseases are characterized by neuronal degeneration, gliosis and accumulation of PrPSc. Mice devoid of PrPC are resistant to scrapie. A fragment of human PrP consisting of amino acids 106-126 that forms fibrils in vitro is toxic to cultured neurons. Here we show that this toxic effect requires the presence of microglia which respond to PrP106-126 by increasing their oxygen radical production. The combined direct and microglia-mediated effects of PrP106-126 are toxic to normal neurons but are insufficient to destroy neurons from mice not expressing PrPC.

Bovine prion sequence, showing octapeptide repeat copper-binding area and toxic fragment:

MVKSHIGSWILVLFVAMWSDVGLCKKRPKPGGGWNTGGSRYPGQGSPGGNRYP

repeat:
PQGGGGWGQPHGGGWGQPHGGGWGQPHGGGWGQPHGGGWGQPHGGGGWG

misc:
QGGTHGQWNKPSKP

neurotoxic:
106 KTNMKHVAGAAAAGA VVGGLG 126 gly, ala, val, leu, lys, thr, asn, met, his,

the rest:
GYMLGSAMSRPLIHFGSDYEDRYYRENMHRYPNQVYYRPVDQYSNQNNFVHDCVNITVKEHTVTTTTKGENFTETDIKMMKRVVEQMCITQYQRESQAYYQRGASVILFSSPPVILLISFLIFLIVG


Copper in biological systems

Beinert H 
Department of Biochemistry, Medical College of Wisconsin, Milwaukee 53226. 

J Inorg Biochem 44: 173-218 (1991) 
AO, amine oxidase MADH, methylamine dehydrogenase;
AAO, ascorbic acid oxidase;
alpha-AE, alpha-amidating enzyme;
Az, azurin;
COX, cytochrome c oxidase;
CP, ceruloplasmin;
DBH, dopamine beta-hydroxylase;
GO, galactose oxidase;
Hc, hemocyanin;
MT, metallotheonein;
NIR, nitrite reductase;
SOD, superoxide dismutase.

Cofactors:

Dopa, 3,4 dihydroxyphenylalanine;
Topa, 3,4,6 trihydroxyphenylalanine;
PLP, pyridoxal-phosphate;
PQQ, pyrrolo-quinoline quinone


Characterization, mapping, and expression of the human ceruloplasmin gene.

Yang F; Naylor SL; Lum JB; Cutshaw S; McCombs JL; Naberhaus KH;
McGill JR; Adrian GS; Moore CM; Barnett DR; et al 

Proc Natl Acad Sci U S A 83: 3257-61 (1986)
Ceruloplasmin (CP) is a copper-binding protein in vertebrate plasma. It is the product of an intragenic triplication and is composed of three homologous domains.. Two clones, CP-1 and CP-2, differed from each other by the presence or absence, respectively, of a deduced sequence of four amino acids. The two clones provided 81% of the sequence encoding CP. Comparison of the nucleotides of the three domains of the CP coding sequence revealed internal domain homology with identity of sequences ranging from 50.1% to 56%. The nucleotide sequence of a homologous human protein, clotting factor VIII, and was found to be 48% identical overall. The CP gene was mapped to human chromosome 3.

The blue oxidases: ascorbate oxidase, laccase and ceruloplasmin

Messerschmidt A; Huber R 
Max-Planck-Institut fur Biochemie, Martinsried. 

Eur J Biochem 187: 341-52 (1990) 
On the basis of the spatial structure of ascorbate oxidase [Messerschmidt, A., Rossi, A., Ladenstein, R., Huber, R., Bolognesi, M., Gatti, G., Marchesini, A., Petruzzelli, R. & Finazzi-Agro, A. (1989) J. Mol. Biol. 206, 513-529], an alignment of the amino acid sequence of the related blue oxidases, laccase and ceruloplasmin is proposed. This strongly suggests a three-domain structure for laccase closely related to ascorbate oxidase and a six-domain structure of ceruloplasmin. These domains demonstrate homology with the small blue copper proteins. The relationships suggest that laccase, like ascorbate oxidase, has a mononuclear blue copper in domain 3 and a trinuclear copper between domain 1 and 3 and ceruloplasmin has mononuclear copper ions in domains 2, 4 and 6 and a trinuclear copper between domains 1 and 6.

Laccase gene from Neurospora crassa: homology to human ceruloplasmin

Germann UA; Lerch K 
Proc Natl Acad Sci U S A 83: 8854-8 (1986) 
The laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) gene from Neurospora crassa was cloned and part of its nucleotide sequence corresponding to the carboxyl-terminal region of the protein has been determined. The analyzed carboxyl-terminal region of laccase exhibits a striking sequence homology to the carboxyl-terminal part of the third homology unit of the multicopper oxidase ceruloplasmin and to a smaller extent, to the low molecular weight blue copper proteins plastocyanin and azurin. Based on amino acid sequence comparison between these proteins, putative copper ligands of N. crassa laccase are proposed. Moreover, these data further support the hypothesis that the small blue copper proteins and the multicopper oxidases have evolved from the same ancestral gene.

Human blood coagulation factor V is homologous to factor VIII and ceruloplasmin

Kane WH; Davie EW 
Proc Natl Acad Sci U S A 83: 6800-4 (1986) 
Coagulation factor V is a high molecular weight plasma glycoprotein that participates as a cofactor in the conversion of prothrombin to thrombin by factor Xa. The coding region includes 651 amino acids from the carboxyl terminus that constitute the light chain of human factor Va and 287 amino acids that are part of the connecting region of the protein. The amino acid sequence of the light chain is homologous (40%) with the carboxyl-terminal fragment (Mr, 73,000) of human factor VIII. Both fragments have a similar domain structure that includes a single ceruloplasmin-related domain followed by two C domains. The carboxyl terminus of the connecting region, however, shows no significant amino acid sequence homology with factor VIII. It is very acidic and contains a number of potential N-linked glycosylation sites. It also contains about 20 tandem repeats of nine amino acids.

Nitrite reductase: a copper protein from Achromobacter cycloclastes

Fenderson FF; Kumar S; Adman ET; Liu MY; Payne WJ; LeGall J 
Department of Biological Structure, University of Washington, Seattle 98195. 

Biochemistry 30: 7180-5 (1991)
The amino acid sequence of the copper-containing nitrite reductase (EC 1.7.99.3) from Achromobacter cycloclastes has been determined. The subunit contains 340 amino acids. The identity of the first seven amino acids is tentative. The sequence has been instrumental in the X-ray structure determination of this molecule; in conjunction with the X-ray structure, ligands to a type I copper atom and a type II copper atom (one of each per subunit) have been identified. Comparison of the sequence to those of multi-copper oxidases such as ascorbate oxidase, laccase, and ceruloplasmin [Messerschmidt, A., & Huber, R. (1990) Eur. J. Biochem. 187, 341-352] reveals that each of two domains seen in the X-ray structure is similar to the oxidases and also to the small blue copper-containing proteins such as plastocyanin. The combination of sequence and structural similarity to ascorbate oxidase and sequence similarity to ceruloplasmin leads to a plausible model for the domain structure of ceruloplasm.

Disulfides and cysteines in human factor VIII

McMullen BA; Fujikawa K; Davie EW; Hedner U; Ezban M 
Department of Biochemistry, University of Washington, Seattle 98195, USA. 

Protein Sci 4: 740-6 (1995) 
The locations of disulfide bonds and free cysteines in the heavy and light chains of recombinant human factor VIII were determined by sequence analysis of fragments produced by chemical and enzymatic digestions. The A1 and A2 domains of the heavy chain and the A3 domain of the light chain contain one free cysteine and two disulfide bonds, whereas the C1 and C2 domains of the light chain have one disulfide bond and no free cysteine. The positions of these disulfide bonds are conserved in factor V and ceruloplasmin except that the second disulfide bond in the A3 domain is missing in both factor V and ceruloplasmin. The positions of the three free cysteines of factor VIII are the same as three of the four cysteines present in ceruloplasmin. However, the positions of the free cysteines in factor VIII and ceruloplasmin are not conserved in factor V.

Hereditary ceruloplasmin deficiency with hemosiderosis

Okamoto N; Wada S; Oga T; Kawabata Y; Baba Y; Habu D; Takeda Z; Wada Y 
Osaka Medical Center and Research Institute for Maternal and Child Health, Japan. 

Hum Genet 97: 755-8 (1996) 
Hereditary ceruloplasmin deficiency with hemosiderosis (aceruloplasminemia) is a new disease characterized by systemic hemosiderosis, diabetes mellitus, neurological abnormalities and pigment degeneration of the retina. Loss of the ferroxidase activity of ceruloplasmin results in systemic iron deposition and tissue damage. Neuroimaging studies reveal iron deposition in basal ganglia and in the red and dentate nuclei. Cerebellar ataxia, extrapyramidal signs and dementia develop after middle age. Sequence analysis of the cDNA of ceruloplasmin from this patient revealed an insertion of adenine in exon 3; this produced a premature stop codon.

Cellular expression of ceruloplasmin in lung: anti-oxidant role

Yang F; Friedrichs WE; deGraffenried L; Herbert DC; Weaker FJ; Bowman BH; Coalson JJ 
Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio 78284, USA. 

Am J Respir Cell Mol Biol 14: 161-9 (1996) 
Ceruloplasmin (CP) is an important extracellular antioxidant and free radical scavenger. Although CP is expressed mainly in the liver, recent studies have identified the lung as another major site of CP synthesis. The sites and cell types that are responsible for CP expression in baboon and mouse lung are described. CP mRNA is detected in primordial bronchial epithelium in baboon fetuses by 60 days of gestation. At 140 days of gestation and thereafter, CP mRNA is found in airway epithelium and in the ductal cells of the submucosal glands. In developing and mature mice, The data suggest that the airway epithelial cells are the major source of CP in the lung fluid and support ceruloplasmin's critical role in host defense against oxidative damage and infection in the lung.

Ceruloplasmin role in LDL oxidation by human monocytic cells

Ehrenwald E; Fox PL 
Department of Cell Biology, Cleveland Clinic Research Institute, Ohio 44195, USA. 

J Clin Invest 97: 884-90 (1996) 
Oxidation of lipids and lipoproteins by macrophages is an important event during atherogenesis. Activation of monocytic cells by zymosan and other agonists results in the release of multiple oxidant species and consequent oxidation of LDL. We now show evidence that ceruloplasmin, a copper-containing acute phase reactant, is secreted by zymosan-activated U937 monocytic cells, and that the protein has an important role in LDL oxidation by these cells. In one approach, ceruloplasmin has been shown to exhibit oxidant activity under the appropriate conditions. Exogenous addition of purified human ceruloplasmin stimulates U937 cell oxidation of LDL to nearly the same extent as activation by zymosan. In contrast to previous cell-free experiments (Ehrenwald, E., G.M. Chisom, and P.L. Fox. 1994. Intact human ceruloplasmin oxidatively modifies low density lipoprotein. J. Clin. Invest. 93:1493-1501.) in which ceruloplasmin by itself (in PBS) oxidizes LDL, under the conditions of the current experiments (in RPMI 1640 medium) ceruloplasmin only oxidizes LDL in the presence of cells; the mechanism by which cells overcome the inhibition by medium components has not been ascertained. In summary, these results are consistent with a mechanism in which cell-derived ceruloplasmin participates in oxidation of LDL. The data also show that cellular factors in addition to ceruloplasmin, possibly active oxygen species and/or lipoxygenases, are essential and act synergistically with ceruloplasmin to oxidize LDL.

Induction of ceruloplasmin in rat lung during hyperoxia

Fleming RE; Whitman IP; Gitlin JD 
Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110. 

Am J Physiol 260: L68-74 (1991) 
We examined the effects of hyperoxia on ceruloplasmin gene expression. Exposure of adult rats to 95% O2 resulted in a five- to sixfold induction of ceruloplasmin mRNA in lung tissue within 46 h, and this response was time dependent, reaching maximum values at 86 h. Hyperoxic induction of ceruloplasmin mRNA was specific to the lung and not the result of systemic inflammation because hepatic ceruloplasmin mRNA content remained constant. These data indicate that the lung is a prominent site of ceruloplasmin gene expression during inflammation and hyperoxia and suggest that this protein may play a previously unappreciated role in pulmonary injury or repair.

Tissue-specific ceruloplasmin gene expression in the mammary gland

Jaeger JL; Shimizu N; Gitlin JD 
Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110. 

Biochem J 280 ( Pt 3): 671-7 (1991) 
Using a ceruloplasmin cDNA clone in RNA blot analysis, a single 3.7 kb ceruloplasmin-specific transcript was detected in rat mammary gland tissue. Ceruloplasmin gene expression in the mammary gland was tissue-specific, with no evidence of expression in brain, heart or other extrahepatic tissues. Biosynthetic studies indicated that the ceruloplasmin mRNA in mammary gland tissue was translated into a 132 kDa protein qualitatively similar to that synthesized in liver. By in situ hybridization, ceruloplasmin gene expression was localized to the epithelium lining the mammary gland alveolar ducts, without evidence of expression in the surrounding mesenchyme. These data indicate that the mammary gland is a prominent site of extrahepatic ceruloplasmin gene expression and add to the evidence that ceruloplasmin biosynthesis is associated with growth and differentiation in non-hepatic tissues.

Ceruloplasmin resistance to proteolysis

Ryan TP; Grover TA; Aust SD 
Biotechnology Center, Utah State University, Logan 84322-4705. 

Arch Biochem Biophys 293: 1-8 (1992)
Rat ceruloplasmin was found to be more resistant to plasmin-mediated proteolysis than was human ceruloplasmin. Both proteins were cleaved initially to products with apparent molecular weights of 116,000 and 20,000 Da. Primary structure differences could account for the different relative stabilities between the two enzymes. Kinetic analysis of rat ceruloplasmin produced a biphasic v vs v/s plot with apparentKm's of 40 and 1.5 microM for iron. Rat ceruloplasmin showed about one-fourth the ferroxidase activity and had a much broader pH profile than that of human ceruloplasmin. Rates of p-phenylenediamine oxidation by rat ceruloplasmin were about one-half those obtained with human ceruloplasmin, with maximal p-phenylenediamine oxidase activity at pH 5.0 for both enzymes.

Ceruloplasmin tissue-specific gene expression during development.

Fleming RE; Gitlin JD 
Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110. 
J Biol Chem 265: 7701-7 (1990) Rat ceruloplasmin nucleotide sequence was obtained. The derived amino acid sequence of rat ceruloplasmin is 93% homologous to the corresponding human sequence and contains a 19-amino acid leader peptide plus 1040 amino acids of mature protein. The ceruloplasmin gene exists as a single copy in the rat haploid genome. These data indicate that lung is the predominant extrahepatic site of ceruloplasmin gene expression during fetal development and suggest that this protein may play a previously unappreciated role in lung development or pulmonary antioxidant defense.

Ceruloplasmin oxidant stimulates growth

Alcain F; Low H; Crane FL 
Endocrinology Department, Karolinska Institute, Stockholm, Sweden. 

Biochem Biophys Res Commun 180: 790-6 (1991)
The incorporation of tritiated thymidine into CCL-39 cells grown in the absence of fetal calf serum or other growth factors is greatly increased by low concentrations of ceruloplasmin. The stimulation is greater than observed with serum or thrombin. Addition of serum decreases the thymidine incorporation with ceruloplasmin to the level with serum alone. As with serum, the response to ceruloplasmin is high at both 20% and 1% oxygen, which is consistent with the action of ceruloplasmin as an oxidant with a high affinity for oxygen. Since transplasma membrane electron transport increases cell growth and thymidine incorporation, ceruloplasmin may act as a terminal oxidase for ferrous iron or ascorbate to stimulate transplasma membrane electron transport. The four electron transfer from ceruloplasmin to oxygen to form water will prevent peroxide formation at the cell surface. Alternatively, superoxide formation inside the cell or membrane could employ the superoxide dismutase function of ceruloplasmin to produce peroxide. Either mechanism would be consistent with the previously described stimulation of growth by external oxidants.

DNA sequence of human pre-ceruloplasmin

Koschinsky ML; Funk WD; van Oost BA; MacGillivray RT 
Proc Natl Acad Sci U S A 83: 5086-90 (1986) 
DNA coding for amino acid residues 202-1046 of the protein, followed by a stop codon, a 3' untranslated region of 123 base pairs, and a poly(A) tail, a probable signal peptide of 19 amino acid residues followed by DNA coding for residues 1-380 of plasma ceruloplasmin. t ceruloplasmin mRNA from human liver is 3700 nucleotides in size. Liver contained an additional mRNA species that is like ceruloplasmin mRNA and is 4500 nucleotides in size. Comparison of the complete nucleotide sequences of human ceruloplasmin cDNA and human clotting factor VIII showed regions of sequence homology.

Aceruloplasminemia: disorder of iron metabolism

Harris ZL; Takahashi Y; Miyajima H; Serizawa M; MacGillivray RT; Gitlin JD 
Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA. 

Proc Natl Acad Sci U S A 92: 2539-43 (1995)
Ceruloplasmin is an abundant alpha 2-serum glycoprotein that contains 95% of the copper found in the plasma of vertebrate species. We report here on the identification of a genetic defect in the ceruloplasmin gene in a patient previously noted to have a total absence of circulating serum ceruloplasmin in association with late-onset retinal and basal ganglia degeneration. Basal ganglia densities consistent with iron deposition. exon 7. DNA sequence analysis of this exon revealed a 5-bp insertion at amino acid 410, resulting in a frame-shift mutation and a truncated open reading frame. These findings support previous studies that identified ceruloplasmin as a ferroxidase and are remarkably consistent with recent studies on the essential role of a homologous copper oxidase in iron metabolism in yeast. The clinical and laboratory findings suggest that additional patients with movement disorders and nonclassical Wilson disease should be examined for ceruloplasmin gene mutations.

Dolphin ceruloplasmin is proteolytically stable

Bonaccorsi di Patti MC; Galtieri A; Giartosio A; Musci G; Calabrese L 
Department of Biochemical Sciences, University of Rome La Sapienza, Italy. 

Comp Biochem Physiol [B] 103: 183-8 (1992) 
EPR spectroscopy and calorimetric analyses indicated a three-domain arrangement of the protein typical of "aged" ceruloplasmin. Dolphin ceruloplasmin is the only mammalian ceruloplasmin insensitive to trypsin, plasmin or chymotrypsin. This property, however, does not result in a higher conformational stability of the molecule. Thus, susceptibility of ceruloplasmin to aging is not directly related to the lability to proteases, which is typical of all other mammalian ceruloplasmins so far studied.
Copper transport from ceruloplasmin: cellular uptake
Percival SS; Harris ED 
Department of Biochemistry and Biophysics, Texas A & M University, College Station 77843. 

Am J Physiol 258: C140-6 (1990)
Copper uptake from 67 Cu-labeled ceruloplasmin These studies provide evidence that K-562 cells are able to extract copper atoms from ceruloplasmin and transport the copper to the cytosol.

Chloride and redox state of the copper sites of ceruloplasmin

Musci G; Bonaccorsi di Patti MC; Calabrese L 
Department of Organic and Biological Chemistry, University of Messina, Italy. musci@axcasp.caspur.it 

J Protein Chem 14: 611-9 (1995) 
Incubation of human ceruloplasmin with physiological concentrations of chloride at neutral pH invariably caused dramatic changes: an oxidized type 1 copper site and from a half-reduced type 3 copper pair. Removal of chloride completely restored the original optical and EPR lineshapes. Hydrogen peroxide, added to ceruloplasmin in the presence of chloride, was able to capture the electron of the half-reduced type 3 site. As a whole, the spectroscopic data indicate that a blue site is partially reduced in the resting protein and that, upon binding of chloride, human ceruloplasmin undergoes a structural change leading to displacement of an electron from the reduced type 1 site to the type 3 site pair. Chloride dramatically affected the catalytic efficiency of human ceruloplasmin. Human ceruloplasmin is, in the plasma, under control of this anion.

Cartilage matrix glycoprotein is closely related to ceruloplasmin

Fife RS; Kluve-Beckerman B; Houser DS; Proctor C; Liepnieks J; Masuda I; McCarty DJ; Ryan LM 
Department of Medicine, Indiana University School of Medicine, Indianapolis 46202. 

J Biol Chem 268: 4407-11 (1993) 
Cartilage matrix glycoprotein (CMGP) is a disulfide-bonded 550,000-dalton protein that is synthesized by chondrocytes and ciliary epithelial cells. We have purified the protein from bovine and porcine articular cartilage and have sequenced two peptides, which both have significant homology with human ceruloplasmin, a copper-binding oxidase. . CMGP is present in bovine chondrocyte membrane preparations CMGP demonstrates oxidase activity towards p-phenylenediamine similar to that of ceruloplasmin. These studies suggest that CMGP is closely related to, if not identical with, ceruloplasmin. It is possible that CMGP may be involved in metal transport into and/or within the chondrocyte.

Ceruloplasmin relationships with the copper-albumin complex

Musci G; Bonaccorsi di Patti MC; Carlini P; Calabrese L 
CNR Center of Molecular Biology, University of Rome La Sapienza, Italy. 

Eur J Biochem 210: 635-40 (1992)
Modified form of type 2 copper bound to ceruloplasmin [(1991) Eur. J. Biochem. 197, 185-189]; serum components trigger the metal exchange, in a defence mechanism operating when ceruloplasmin leaks, by unknown processes, its copper content before discharging the metal into the various organs.

The 5'-flanking region of ceruloplasmin gene

Fleming RE; Gitlin JD 
Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110. 

J Biol Chem 267: 479-86 (1992) 
Rat ceruloplasmin gene revealed a typical eukaryotic promotor structure, but no obvious homology with cis-acting elements previously characterized as determining tissue-specific gene expression. The region from -393 to -348 was determined by deletion analysis to contain a positive-acting element, and includes sequence partially homologous to the rat albumin D site. These data indicate that ceruloplasmin gene expression is determined in part by a cis-acting region 393 bp upstream of the transcription start site, which binds a previously uncharacterized nuclear protein. The tissue distribution of this nuclear protein suggests that it plays a role in directing ceruloplasmin gene expression in lung and liver during development.

A nonsense mutation of the ceruloplasmin

Daimon M; Kato T; Kawanami T; Tominaga M; Igarashi M; Yamatani K; Sasaki H 
Third Department of Internal Medicine, Yamagata University School of Medicine, Japan. 

Biochem Biophys Res Commun 217: 89-95 (1995) 
A novel mutation of the ceruloplasmin gene was found in a patient with hereditary ceruloplasmin deficiency (HCD) daughter revealed a novel point mutation, G to A, at nucleotide 2630 in exon 15. This mutation changes the Trp858 codon (TGG) to a stop codon (TAG) (nonsense mutation).patient as well as his daughter was a heterozygote for the mutation.
Labile conformation of type 2 Cu2+ centres in human ceruloplasmin.
Rylkov VV; Tarasiev MYu; Moshkov KA 
State Optical Institute, Leningrad, USSR. 

Eur J Biochem 197: 185-9 (1991) 
Human ceruloplasmin: type 2 Cu2(+)-containing centres occur not in one, but in two stable forms both forms of these centres exist in the blood serum. The ferroxidase activity of ceruloplasmin against hemoglobin The conformational state of ceruloplasmin molecules plays an essential role in its oxidase activity.
Effects of cellular copper content on copper uptake and metallothionein and ceruloplasmin mRNA levels in mouse hepatocytes. McArdle HJ; Mercer JF; Sargeson AM; Danks DM Department of Child Health, Ninewells Hospital, University of Dundee, Scotland, UK. J Nutr 120: 1370-5 (1990) The intracellular copper content of mouse hepatocytes has been altered by increasing amounts of diamsar, a copper chelator. Metallothionein 1 (MT1) and MT2 mRNA levels in the cells increased in proportion to the intracellular copper concentration. neither ceruloplasmin production nor copper uptake is regulated by intracellular copper levels.
Presence of coupled trinuclear copper cluster in mammalian ceruloplasmin is essential for efficient electron transfer to oxygen. Calabrese L; Carbonaro M; Musci G Department of Biochemical Sciences, Universita La Sapienza, Roma, Italy. J Biol Chem 264: 6183-7 (1989) The reactivity with dioxygen of a mammalian (sheep) ceruloplasmin, anaerobically reduced with ascorbate, was found to depend on the state of the Type 2 and Type 3 copper centers. A complete reoxidation by air after anaerobic reduction with ascorbate was observed with chicken ceruloplasmin ( (1988) J. Biol. Chem. 263, 6480), reflecting the functional nonequivalence of blue coppers which is considered a typical property of mammalian ceruloplasmin. The presence of a trinuclear Type 2-Type 3 cluster can therefore be proposed for all ceruloplasmins, and the integrity of the copper-copper coupling is essential for efficient oxidase behavior.
[Localization of active sites in human ceruloplasmin from data of intra- and intermolecular homology] Moshkov KA; Vagin AA; Zaitsev VN Mol Biol (Mosk) 21: 1124-9 (1987) The identification of possible copper ligands in human ceruloplasmin was carried out by the computer similarity analysis for sequences of ceruloplasmin and several other copper oxidases: azurin, plastocyanin, superoxide dismutase, tyrosinase and hemocyanin. It follows from the analysis of inter- and intramolecular homology that copper active sites of different types appeared to be in close contacts within the ceruloplasmin molecule.
The Menkes/Wilson disease gene homologue in yeast provides copper to a ceruloplasmin-like oxidase required for iron uptake. Yuan DS; Stearman R; Dancis A; Dunn T; Beeler T; Klausner RD Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA. Proc Natl Acad Sci U S A 92: 2632-6 (1995) The CCC2 gene of the yeast Saccharomyces cerevisiae is homologous to the human genes defective in Wilson disease and Menkes disease. A biochemical hallmark of these diseases is a deficiency of copper in ceruloplasmin and other copper proteins found in extracytosolic compartments. Here we demonstrate that disruption of the yeast CCC2 gene results in defects in respiration and iron uptake. These defects could be reversed by supplementing cells with copper, suggesting that CCC2 mutant cells were copper deficient. However, cytosolic copper levels and copper uptake were normal. Instead, CCC2 mutant cells lacked a copper-dependent oxidase activity associated with the extracytosolic domain of the FET3-encoded protein, a ceruloplasmin homologue previously shown to be necessary for high-affinity iron uptake in yeast. Copper restored oxidase activity both in vitro and in vivo, paralleling the ability of copper to restore respiration and iron uptake. These results suggest that the CCC2-encoded protein is required for the export of copper from the cytosol into an extracytosolic compartment, supporting the proposal that intracellular copper transport is impaired in Wilson disease and Menkes disease.
Partial purification of the rat erythrocyte ceruloplasmin receptor monitored by an electrophoresis mobility shift assay. Stern RV; Frieden E Chemistry Department B-164, Florida State University, Tallahassee 32306-3006. Anal Biochem 212: 221-8 (1993) Ceruloplasmin (Cp), the main copper transport glycoprotein found in the blood, delivers its copper to intracellular proteins via a plasma membrane receptor protein. With this technique the subunit M(r) of the receptor was approximately 56,000.
[Distribution of serum haptoglobin groups in affective psychoses--more than a genetic marker indication?] Lange V Humangenetik im Fachbereich Biologie, Universitat Frankfurt a. M. Fortschr Neurol Psychiatr 58: 114-21 (1990) The haptoglobin serum group 2-2 has a preponderance in affective psychoses This genetic marker trait is extended on unipolar depressions) and cycloid psychoses. In addition, it must be assumed that the serum levels of albumin, ceruloplasmin (p less than 0.0001) and haptoglobin are increased in affective disorders. Besides, the transferrin serum values are decreased in cycloid psychoses.
[HLA and ceruloplasmin phenotypes in lupus erythematosus and circumscribed scleroderma] Glavinskaia TA; Rezaikina AV; Komarova VD; Sidorova TI Vestn Dermatol Venerol 83: 9-13 (1989) The incidence rates of combinations of A and B loci histocompatibility antigens in loci and haplotypes and of ceruloplasmin phenotypes have been examined in 137 patients with lupus erythematosus (LE) and scleroderma circumscriptum (SC). The studies have revealed that LE and SC are associated with certain haplotypes and HLA antigens combinations, this indicating the contribution of these phenotypes to the realization of the genetic predisposition to these diseases. In A1B8 haplotype carriers the disease is characterized by a benign course and manifests by integument forms of LE and scleroderma. IN A2B8 haplotype carriers the disease is more grave and presents as the systemic variant of LE. The third type of ceruloplasmin not detectable in normal subjects is usually associated with A9B18, A25B18, A3B27 haplotypes and with HLA A3A9 antigenic combination mostly in LE patients.
Interaction of neocuproine, 1,10-phenanthroline and 2,2'-dipyridyl with human ceruloplasmin. Lovstad RA Institute of Medical Biochemistry, University of Oslo, Norway. Int J Biochem 20: 117-9 (1988) Neocuproine binding to ceruloplasmin markedly increases the chlorpromazine-ceruloplasmin-catalyzed oxidation of NADH. 2. 1,10-Phenanthroline and 2,2'-dipyridyl inhibit neocuproine activation in a competitive manner. 3. The order of enzyme chelator complex stability was: phenanthroline greater than dipyridyl greater than neocuproine.
Genetic and molecular basis for copper toxicity. Harris ZL; Gitlin JD Department of Pediatrics, Washington University School of Medicine, St Louis, MO 63110, USA. Am J Clin Nutr 63: 836S-41S (1996) Recent studies resulted in the cloning of the genes responsible for Menkes syndrome and Wilson disease. Despite the distinct clinical phenotypes of these disorders, each gene encodes a highly homologous member of the

cation-transport P-type ATPase family

. The remarkable evolutionary conservation of these proteins in bacteria, yeast, plants, and mammals reveals a fundamental protein structure essential for copper export in all life forms. Characterization of a molecular defect in the rat homologue of the Wilson ATPase; role of this ATPase in copper transport, the effects of specific inherited mutations on transport function, and the cellular and molecular mechanisms of tissue injury resulting from copper accumulation. Finally, recent molecular genetic analysis of a distinct group of patients with low serum ceruloplasmin and basal ganglia symptoms identified a series of mutations in the ceruloplasmin gene. The presence of these mutations in conjunction with the clinical and pathologic findings clarifies the essential biological role of this abundant copper protein in metal metabolism and identifies aceruloplasminemia as a novel autosomal recessive disorder of iron metabolism.
Specific proteolysis of ceruloplasmin by leukocyte elastase. Sang QA Department of Chemistry, Florida State University, Tallahasse 32306-3006, USA. Biochem Mol Biol Int 37: 573-81 (1995) Ceruloplasmin (Cp) is a major copper transporting plasma protein. The susceptibility of porcine Cp by human leukocyte elastase and plasmin has been investigated. The 116 and 48 kDa bands induced by both proteinases have the same N-terminal sequences which are identical to that of the 132 kDa Cp species, KDKHYYIGIVET. The 70 kDa band generated by elastase has a N-terminal sequence of IGGKVVVYYYIA, and the 68 kDa band generated by plasmin has that of TIIEDAIVGKKV. The 19 kDa bands produced by elastase and plasmin have N-terminal sequences of FNPIKNLLFFLL and VFNPIKNLLFFL, respectively. The novel observations suggest that, in addition to plasmin, leukocyte elastase may play a role in angiogenesis and inflammation by digesting Cp.
Dinucleotide repeat polymorphism in the human ceruloplasmin gene. Daimon M; Morita Y; Yamatani K; Igarashi M; Fukase N; Kawanami T; Kato T; Tominaga M; Sasaki H Third Department of Internal Medicine, Yamagata University School of Medicine, Japan. Hum Genet 96: 736 (1995) We have identified a GT dinucleotide repeat polymorphism in intron 14 of the human ceruloplasmin gene. Observed heterozygosity for the polymorphism is 0.84.
A mutation in the ceruloplasmin gene is associated with systemic hemosiderosis in humans. Yoshida K; Furihata K; Takeda S; Nakamura A; Yamamoto K; Morita H; Hiyamuta S; Ikeda S; Shimizu N; Yanagisawa N Department of Medicine (Neurology), Shinshu University School of Medicine, Matsumoto, Japan. Nat Genet 9: 267-72 (1995) We identified a mutation in the ceruloplasmin (Cp) gene in a Japanese family with aceruloplasminemia, some of whose members showed extrapyramidal disorders, cerebellar ataxia, and diabetes mellitus. A post-mortem study of the proband revealed excessive iron deposition mainly in the brain, liver and pancreas. The G to A transition at the splice acceptor site introduces a premature termination codon at the amino acid position 991 by defective splicing, thereby truncating the carboxyl terminus of Cp in affected individuals. We conclude that the mutation in the Cp gene is associated with systemic hemosiderosis in humans. A mutation in the ceruloplasmin gene is associated with systemic hemosiderosis in humans. Yoshida K; Furihata K; Takeda S; Nakamura A; Yamamoto K; Morita H; Hiyamuta S; Ikeda S; Shimizu N; Yanagisawa N Department of Medicine (Neurology), Shinshu University School of Medicine, Matsumoto, Japan. Nat Genet 9: 267-72 (1995) We identified a mutation in the ceruloplasmin (Cp) gene in a Japanese family with aceruloplasminemia, some of whose members showed extrapyramidal disorders, cerebellar ataxia, and diabetes mellitus. A post-mortem study of the proband revealed excessive iron deposition mainly in the brain, liver and pancreas. The G to A transition at the splice acceptor site introduces a premature termination codon at the amino acid position 991 by defective splicing, thereby truncating the carboxyl terminus of Cp in affected individuals. We conclude that the mutation in the Cp gene is associated with systemic hemosiderosis in humans.
Fine structure of the human ceruloplasmin gene. Daimon M; Yamatani K; Igarashi M; Fukase N; Kawanami T; Kato T; Tominaga M; Sasaki H Third Department of Internal Medicine, Yamagata University, School of Medicine, Japan. Biochem Biophys Res Commun 208: 1028-35 (1995) We characterized the genomic region corresponding to the human ceruloplasmin cDNA previously reported. Using PCR-direct sequencing methods, we determined precise intron/exon boundaries and intron-exon composition of the gene in the region. The gene region spanned about 50 kb and was composed of 19 exons and 18 introns. The lengths of exons and introns range from 107 to over 267 bp and from 0.44 to 10.0 kb, respectively. The translation initiation codon and the termination codon were located in exons 1 and 19, respectively. The nucleotide sequences of the introns were also determined in the region around the intron/exon boundaries for 24-220 bp. All the sequences around the intron/exon boundaries were consistent with the 5' and 3' consensus sequences for splice junctions of transcribed genes. Putative lariat sequences were identified between -17 and -42 nucleotides from the 3' splice junction for all 18 introns.
Ceruloplasmin gene defect associated with epilepsy in EL mice. Garey CE; Schwarzman AL; Rise ML; Seyfried TN Department of Biology, Boston College, Chestnut Hill, Massachusetts 02167. Nat Genet 6: 426-31 (1994) Epilepsy is a dominant trait in EL mice, a model for human complex partial seizures. We recently mapped the major gene, El-1, to chromosome 9 near the predicted location for the ceruloplasmin (Cp) gene. We now present evidence for a partial duplication in the Cp gene in EL mice. This Cp duplication is coinherited with seizures in backcross generations and is associated with enhanced expression of Cp mRNA and increased Cp oxidase activity. Moreover, the duplication is associated with an enhanced frequency of double recombinants, simulating negative interference.
Chromosome assignments of genes for rat ceruloplasmin (CP) and metallothionein (MT). Miura M; Yamada T; Moralejo DH; Agui T; Yamada J; Serikawa T; Matsumoto K Institute for Animal Experimentation, University of Tokushima School of Medicine, Japan. Cytogenet Cell Genet 65: 119-21 (1994) Chromosome assignments of the genes for rat ceruloplasmin (CP) and metallothionein (MT) were performed by analyzing somatic cell hybrid DNAs with the polymerase chain reaction (PCR), using primers specific for rat genes. The genes for CP and MT were assigned to rat chromosomes 2 and 19, respectively.
[Ceruloplasmin in patients with Duchenne muscular dystrophy] Reyes J; Holmgren J; Colombo M Universidad de Valparaiso, Instituto de Rehabilitacion Infantil, Universidad de Chile, Santiago. Rev Med Chil 119: 258-61 (1991) Duchenne muscular dystrophy is a well defined form of sex linked inherited muscular disease. Approximately 1/3 of cases are the product of a new mutation. We studied 20 patients with this disease and 19 heterozygous females. Ceruloplasmin levels were significantly higher in patients compared to controls. A possible protective role of this enzyme against oxydating agents may help prevent peroxydation of lipids from the smooth muscle cell membrane.
Binding of transition metals by apolipoprotein A-I-containing plasma lipoproteins: inhibition of oxidation of low density lipoproteins. Kunitake ST; Jarvis MR; Hamilton RL; Kane JP Cardiovascular Research Institute, University of California, San Francisco 94143-0130. Proc Natl Acad Sci U S A 89: 6993-7 (1992) We have found transition metals tightly bound to apolipoprotein A-I-containing lipoproteins [Lp(A-I)] we detected both transferrin and ceruloplasmin. HDL inhibit copper-catalyzed oxidation of low density lipoproteins (LDL) in vitro. When the Lp(A-I) particles containing transferrin and ceruloplasmin were removed from the bulk of Lp(A-I), inhibition of the in vitro oxidation of LDL was significantly decreased.
[Biosynthesis of ceruloplasmin in various rat organs] Puchkova LV; Denezhkina VV; Zakharova ET; Gaitskhoki VS; Neifakh SA Biokhimiia 55: 2095-102 (1990) Ceruloplasmin (CP) biosynthesis in various organs of the rat was studied. It was found that the translation products of postmitochondrial extracts of various organs of the rat contain immunoreactive polypeptides of CP. In respect of proteolytic fragments formed during the digestion with staphylococcal protease V8, these polypeptides do not differ from one another. At the same time, in Golgi vesicles of the kidney, brain and liver the mature molecular forms of CP differ not only by their molecular properties, but also by the number of CP isoforms. For example, the organs which do not secrete CP, contain only one isoform of CP. The secreted form of CP was found to be tissue-nonspecific. The third molecular form of CP found in the liver has no counterparts in the other organs. Immunochemical analysis of mature forms of CP isolated from liver Golgi vesicles provided additional evidence in favour of molecular heterogeneity of CP secreted by the liver. The mechanism of production of multiple molecular forms of CP and their roles in copper metabolism are postulated.
The protective effect of different forms of human ceruloplasmin in copper-induced lysis of red blood cells. Saenko EL; Yaropolov AI A.N. Bach Institute of Biochemistry, USSR Academy of Sciences, Moskow. Biochem Int 22: 57-66 (1990) The comparison of protective effects of native ceruloplasmin (CP) and of preparation CP1 containing carbohydrate fragment GlcNAc(beta(1,4]GlcNAc which specifically binds on RBC (alpha(1,6)Fuc receptors showed that CP1 exhibits much more powerful protective effect on RBC in copper-induced lysis. It was found, however, that CP2 (native CP devoided of CP1) protected RBC as well as CP despite its inability of binding to RBC membrane. CP and CP1 in a similar way decrease copper concentration in RBC. It was shown that copper accumulation and GSH decrease in RBC are two independent and concurrent processes; the copper and GSH concentrations are not the factors determining RBC resistance to hemolysis. CP inhibits the reaction of superoxide radicals generation as a result of Cu interaction with -SH groups of RBC membrane; the effect is more pronounced than the effect of catalase or superoxide dismutase. CP and CP1 preparations equally inhibit this reaction. Apparently CP reception on RBC leads not only to membrane protection from superoxide and hydroxyl radicals but represents a more complex process.
[Expression of ceruloplasmin gene in various organs of the rat] Gaitskhoki VS; Voronina OV; Denezhkina VV; Pliss MG; Puchkova LV; Shvartsman AL; Neifakh SA Biokhimiia 55: 927-37 (1990) synthesis of ceruloplasmin from liver, heart, kidney as well as from different divisions of brain, the concentration of Cp mRNA sequences being maximal in the liver. the liver is the only organ secreting Cp into the blood stream. It was suggested that mammalian tissues contain at least two molecular forms of Cp, i. e., circulatory and intracellular ones.
[Expression of ceruloplasmin gene in mammalian organs from the data of hybridization analysis with complementary DNA probes] Shvartsman AL; Voronina OV; Gaitskhoki VS; Patkin EL Mol Biol (Mosk) 24: 657-62 (1990) Expression of ceruloplasmin (Cp)-coding gene in rat and human liver and brain tissues was studied. In rat brain structures, the maximal one was found in cerebellum. brain polyadenylated RNA contains a single Cp mRNA (4.5 kb).
Binding of Cu(II) to non-prosthetic sites in ceruloplasmin and bovine serum albumin. Zgirski A; Frieden E Department of Chemistry, Florida State University, Tallahassee 32306-3006. J Inorg Biochem 39: 137-48 (1990) The binding of Cu(II) to native human, porcine, bovine and ovine ceruloplasmin (Cp) and to bovine serum albumin (bSA) has been studied at pH 7.4, 30 mM barbital buffer. The results were analyzed for the strength and the number of binding sites using Scatchard plots. Evidence for additional copper binding sites in Cp and bSA was obtained suggesting a role for copper ion in the homeostatic regulation of Cu(II) and other metal ions in the serum.
Linkage between the loci for transferrin and ceruloplasmin in pigs. Juneja RK; Kuryl J; Gahne B; Zurkowski M Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala. Anim Genet 20: 307-11 (1989) Evidence for genetic linkage between the loci for transferrin (Tf) and ceruloplasmin (Cp) in pigs was presented. The results were based on a study of a single sire family comprising 35 informative offspring. No recombinants were observed. The recombination frequency was estimated to be in the range of 0 to 8%. This indicated that the recombination frequency between Tf and Cp loci in pigs may be much lower than that reported previously between these two loci in cattle and in human.
In vitro metabolic transformations of vinblastine: oxidations catalyzed by human ceruloplasmin. Elmarakby SA; Duffel MW; Rosazza JP Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Iowa, Iowa City 52242. J Med Chem 32: 2158-62 (1989) The dimeric Vinca alkaloid vinblastine (VLB) undergoes metabolic transformation to three products in a reaction catalyzed by the human serum copper oxidase ceruloplasmin. The enzyme reaction requires chlorpromazine as a shuttle oxidant, and the course of the oxidation reaction appears to be subject to the nature of the shuttle oxidant used. Preparative-scale incubations have resulted in the isolation of three products, which were characterized by chemical and spectral analyses. The metabolites were identified as the ring fission product catharinine, obtained by oxidation of the Iboga ring system; an enamine/ether derivative obtained by oxidation of the Aspidosperma portion of VLB; and a metabolite embodying the same structural changes in both parts of the vinblastine dimeric structure. Catharinine is identical with the product of VLB oxidation obtained by peroxidase oxidation. The other two products are new metabolites and are derivatives of VLB.
Localization of the processed gene for human ceruloplasmin to chromosome region 8q21.13----q23.1 by in situ hybridization. Wang H; Koschinsky M; Hamerton JL Department of Human Genetics, University of Manitoba, Winnipeg, Canada. Cytogenet Cell Genet 47: 230-1 (1988) A processed gene for human ceruloplasmin has been localized to 8q21.13---q23.1 by in situ hybridization. This result confirms the assignment of this locus to chromosome 8 by Southern blot analysis using human x hamster somatic-cell hybrids and localizes the gene to the long arm of chromosome 8.
Isolation and characterization of a processed gene for human ceruloplasmin. Koschinsky ML; Chow BK; Schwartz J; Hamerton JL; MacGillivray RT Department of Biochemistry, University of British Columbia, Vancouver, Canada. Biochemistry 26: 7760-7 (1987) A processed pseudogene for human ceruloplasmin has been isolated that contains DNA corresponding to the functional gene sequence encoding the carboxy-terminal 563 amino acid residues and the 3' untranslated region. The pseudogene appears to have arisen from a processed RNA species, since intervening sequences coincident with those of the functional gene have been removed, with the exception of a short segment of intronic sequence which denotes the 5' boundary of the pseudogene. The nucleotide sequence of the pseudogene is highly homologous (97% sequence identity) with that of the wild-type gene, suggesting that pseudogene formation was a relatively recent evolutionary event. In addition to single base substitutions, there is a large 213 base pair (bp) deletion in the pseudogene sequence which corresponds to the location of an intron-exon junction in the functional gene. A 4 bp duplication that occurs at amino acid residue 683 of the wild-type coding sequence results in a frameshift mutation and introduces a premature translational termination codon at this point. This is concordant with the inability to detect a human liver transcript corresponding to the pseudogene by nuclease S1 mapping analysis. The 3' end of the pseudogene is characterized by a 62 bp segment composed mainly of repeated TC dinucleotides. On the basis of genomic Southern blot analysis performed under high-stringency conditions, the pseudogene that we have identified seems to comprise the only sequence in the human genome that is closely related to the wild-type gene. Using somatic cell hybridization, we have mapped the pseudogene to human chromosome 8.
Early copper therapy in classic Menkes disease patients with a novel splicing mutation. Kaler SG; Buist NR; Holmes CS; Goldstein DS; Miller RC; Gahl WA Section on Human Biochemical Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1424, USA. Ann Neurol 38: 921-8 (1995) To correlate genotype with response to early copper histidine therapy in Menkes disease, an X-linked disorder of copper transport, we performed mutational analysis in 2 related males who began treatment at the age of 10 days and prenatally at 32 weeks' gestation, respectively. A G to T transversion at the -1 exonic position of a splice donor site was identified, predicting a glutamine to histidine substitution at codon 724 of the Menkes copper-transporting ATPase gene. The Q724H mutation disrupts proper splicing and generates five mutant transcripts that skip from one to four exons. None of these transcripts is predicted to encode a functional copper transport protein. Copper histidine treatment normalized circulating copper and ceruloplasmin levels but did not improve the baseline deficiency of dopamine-beta-hydroxylase, a copper-dependent enzyme. At the age of 36 months, the first patient was living and had neurodevelopmental abilities ranging from 10 to 15 months. We conclude that early copper histidine therapy does not normalize neurological outcome in patients with the Q724H splicing mutation.
Wilson's disease: a new gene and an animal model for an old disease. Cuthbert JA Department of Internal Medicine, University of Texas Southwestern Medical Center at Dallas, TX 75235-8887, USA. J Investig Med 43: 323-36 (1995) Wilson's disease is an autosomal recessive, inherited disorder of copper metabolism. In normal individuals, copper homeostasis is controlled by the balance between intestinal absorption of dietary copper and hepatic excretion of excess copper in bile. In Wilson's disease, hepatic copper is neither excreted in bile nor incorporated into ceruloplasmin and copper accumulates to toxic levels. The Wilson's disease gene (WND) encodes a putative copper-transporting protein that is expressed almost exclusively in the liver. The predicted structure of the protein product is that of a P-type ATPase with striking homology to bacterial copper transporters and the gene product of another inherited disorder of copper metabolism, Menkes' disease. Clinical manifestations of Wilson's disease indirectly after the release of copper from the liver with subsequent damage to the brain (neuropsychiatric presentation) and other organs.

. Management of Wilson's disease involves decreasing excess levels of copper accumulated in the liver, brain, and other organs. Copper chelation therapy, to increase urinary excretion of copper, is the mainstay of treatment. In addition, oral zinc therapy may be useful at decreasing absorption of dietary copper and rendering tissue copper nontoxic, by increasing the formation of complexes with copper-binding proteins. Liver transplantation can be necessary for individuals with acute hepatic failure or complications of cirrhosis. Gene therapy may evolve in the future; however, medical management is effective in most patients.


Copper-induced tissue factor expression in human monocytic THP-1 cells and its inhibition by antioxidants. Crutchley DJ; Que BG Miami Heart Research Institute, Miami Beach, FL 33140, USA. Circulation 92: 238-43 (1995) Transition metals such as copper are known to initiate free radical formation and lipid peroxidation. These effects were seen only in the presence of a lipophilic chelating agent, 8-hydroxyquinoline, suggesting that intracellular transport of Cu2+ was required. The effects of Cu2+ were mimicked by ceruloplasmin but not by Fe3+ or hemin. . The effects of Cu2+ were inhibited by a number of lipophilic antioxidants, including probucol, vitamin E, butylated hydroxytoluene, and a 21-aminosteroid, U74389G.
Reading the molecular clock from the decay of internal symmetry of a gene. Gibbs PE; Dugaiczyk A Department of Biochemistry, University of California, Riverside 92521. Proc Natl Acad Sci U S A 91: 3413-7 (1994) The closely related serum albumin, alpha-fetoprotein, and vitamin D-binding proteins are derived from a common ancestor, which itself was the result of a triplication of an ancestral gene. We have aligned the sequences of these proteins against themselves to assess the degree to which the ancestral 3-fold symmetry has been retained; in a dot plot, relics of the molecular symmetry appear as a series of alignments parallel to the main diagonal. The decay of internal symmetry reflects the rate of change of a gene in a single line of evolutionary descent. We examined 11 serum albumins, 2 ceruloplasmins, 3 alpha-fetoproteins, and 3 vitamin D-binding proteins. We have found that ceruloplasmin evolves at the same rate in human and rat.
Role of oxidative modification in the lability of ceruloplasmin. Winyard PG; Hider RC; Lunec J; Drake AF; Blake DR Dept. of Rheumatology, Medical School, University of Birmingham, England. Basic Life Sci 49: 341-5 (1988)
Relationship of the glycan structure of glycoproteins to the desialylation process by rat liver endothelium. Irie S; Minguell JJ; Tavassoli M Veterans Administration Medical Center, Jackson, Mississippi. Biochem Int 19: 345-52 (1989) To investigate the variations in desialylation of glycoproteins by liver endothelium, we compared endothelial desialylation for 3 glycoproteins, human ceruloplasmin, human and rat transferrin. Radiolabeled glycoproteins were chased through purified rat liver endothelium and then fractionated by lectin affinity chromatography. Endothelium processed glycoproteins were fractionated by RCA120 chromatography into sialylated and desialylated components. The latter was then studied by Con A chromatography. Desialylation occurred only when the molecule contained at least a single triantennary chain of glycan. Desialylation was minimal in the case of human transferrin which contains mostly biantennary branching pattern. Thus, it appears that a single triantennary glycan chain is necessary and sufficient to trigger desialylation of glycoproteins by liver endothelium and this process is an all-or-none phenomenon.
Molecular cloning and nucleotide sequence of full-length cDNA for ascorbate oxidase from cultured pumpkin cells. Esaka M; Hattori T; Fujisawa K; Sakajo S; Asahi T Laboratory of Enzyme Chemistry, Faculty of Applied Biological Science, Hiroshima University, Japan. Eur J Biochem 191: 537-41 (1990) pPumpkin ascorbate oxidase. The nucleotide sequence of the cDNA insert was found to contain an open reading frame of 579 codons corresponding to a signal peptide of 30 amino acids and the mature 549-residue ascorbate oxidase. Furthermore, it was found that the amino acid sequence deduced from the nucleotide sequence of the cDNA insert contained four potential N-glycosylation sites and copper-binding amino acid residues located in four regions where the sequence was identical or nearly identical to those of the other known blue multicopper oxidases Neurospora crassa laccase and human ceruloplasmin.
Copper-64 metabolism in two patients with non-Wilsonian movement disorders and copper deficiency. Wierzbicki AS; Patel N; Evans K; Lascelles PT Department of Chemical Pathology, Charing Cross and Westminster Medical School, Chelsea. J Neurol Sci 119: 85-90 (1993) Copper-64 studies are presented of 2 patients with non-Wilsonian movement disorder and with abnormal copper handling. Both patients differed from the usual phenotype of non-Wilsonian low copper movement disorder as they had choreiform movement disorders with an onset in the first decade; one patient lacked significant intellectual impairment. Both patients had reduced serum total copper and marginal free copper and caeruloplasmin levels, and both patients were capable of incorporating 64Cu2+ into caeruloplasmin but the second case did so at markedly reduced level. Both showed slightly increased basal and stimulated urinary copper loss compared to normal controls with the rate in patient 1 being capable of leading to copper depletion. Liver copper content was normal in both cases. These 2 patients add to the reports of cases with copper deficiency and movement disorder in whom copper chelation therapy is unlikely to be beneficial.
Hereditary caeruloplasmin deficiency, dementia and diabetes mellitus. Logan JI; Harveyson KB; Wisdom GB; Hughes AE; Archbold GP Belfast City Hospital, Queen's University of Belfast, UK. QJM 87: 663-70 (1994) We report two brothers with complete caeruloplasmin deficiency. The brothers presented with dementia and diabetes mellitus. Twelve relatives have partial caeruloplasmin deficiency. There is no copper overload. Transmission is autosomal recessive. DNA analysis showed genetic linkage between the deficiency and various polymorphic markers flanking the caeruloplasmin gene on chromosome 3q25. This is consistent with a mutation of the caeruloplasmin gene. Caeruloplasmin catalyses the oxidation of ferrous iron to ferric iron. Both brothers have low serum iron and increased liver iron. The index patient was given caeruloplasmin-containing, fresh-frozen plasma. A dose of 2.6 mg caeruloplasmin increased serum iron from 5 microM/l to 10 microM/l. A dose of approximately 72 mg increased serum iron from 5 microM/l to 19 microM/l. The abnormal serum and liver iron levels, and the caeruloplasmin-induced rise in serum iron, confirm a previous suggestion that caeruloplasmin maintains the normal rate of flow of iron from store to transferrin. Dementia and diabetes mellitus have been described in only one other homozygote. The absence of copper overload, and the linkage of the deficiency with chromosome 3q25, distinguish this condition from Wilson's disease.
The FET3 gene product required for high affinity iron transport in yeast is a cell surface ferroxidase. De Silva DM; Askwith CC; Eide D; Kaplan J Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah 84132. J Biol Chem 270: 1098-101 (1995) The yeast FET3 gene is required for high affinity iron transport (1994) Cell 76, 403-410. The gene has extensive sequence homology to the family of multi-copper oxidases. In this communication, we demonstrate that the gene product is a cell surface ferroxidase involved in iron transport. Cells that contain a functional FET3 gene product exhibited an iron-dependent non-mitochondrial increase in oxygen consumption. Comparison of the rate of iron oxidation to O2 consumption yielded an approximate value of 4:1, as predicted for a ferroxidase. Spheroplasts obtained from cells grown under low iron conditions also displayed an iron-dependent increase in O2 consumption. Treatment of spheroplasts with trypsin or affinity-purified antibodies directed against the putative external ferroxidase domain of Fet3 had no effect on basal O2 consumption but inhibited the iron-dependent increase in O2 consumption. Anti-peptide antibodies directed against the cytosolic domain of Fet3 had no effect on O2 consumption. These studies indicate that Fet3 is a plasma membrane ferroxidase required for high affinity iron uptake, in which the ferroxidase-containing domain is localized on the external cell surface.
Primary structure of cucumber (Cucumis sativus) ascorbate oxidase deduced from cDNA sequence: homology with blue copper proteins and tissue-specific expression. Ohkawa J; Okada N; Shinmyo A; Takano M Department of Fermentation Technology, Faculty of Engineering, Osaka University, Japan. Proc Natl Acad Sci U S A 86: 1239-43 (1989) ascorbate oxidase revealed a 1761-base-pair open reading frame that encoded an NH2-terminal signal peptide of 33 amino acids and a mature enzyme of 554 amino acids (Mr, 62,258). The amino acid sequence deduced from nucleotide sequence analysis agrees with the NH2-terminal amino acid sequence of the purified ascorbate oxidase, as determined by microsequencing methods. Cucumber ascorbate oxidase contained four histidine-rich regions with striking sequence homology to the corresponding parts of the other multicopper oxidases such as Neurospora crassa laccase and human ceruloplasmin and, to some extent, to a low molecular weight copper protein such as plastocyanin. Moreover, these data further support the hypothesis that the small blue copper proteins and the multicopper oxidases have evolved from the same ancestral gene.
Mapping HSA 3 loci in cattle: additional support for the ancestral synteny of HSA 3 and 21. Threadgill DS; Womack JE Department of Veterinary Pathology, Texas A&M University, College Station 77843. Genomics 11: 1143-8 (1991) Homologs to genes residing on human chromosome 3 (HSA 3) map to four mouse chromosomes (MMU) 3, 6, 9, and 16. In the bovine, two syntenic groups that contain HSA 3 homologs, unassigned syntenic groups 10 (U10) and 12 (U12), have been defined. U10 also contains HSA 21 genes, which is similar to the situation seen on MMU 16, whereas U12 apparently contains only HSA 3 homologs. The syntenic arrangement of other HSA 3 homologs in the bovine was investigated by physically mapping five genes through segregation analysis of a bovine-hamster hybrid somatic cell panel. The genes mapped include Friend-murine leukemia virus integration site 3 homolog (FIM3; HSA 3/MMU 3), sucrase-isomaltase (SI) and glutathione peroxidase 1 (GPX1) (HSA 3/MMU ?), murine leukemia viral (v-raf-1) oncogene homolog 1 (RAF1; HSA 3/MMU 6), and ceruloplasmin (CP; HSA 3/MMU 9). FIM3, SI, and CP mapped to bovine syntenic group U10, while RAF1 and GPX1 mapped to U12.
Structure of the gene for human coagulation factor V. Cripe LD; Moore KD; Kane WH Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710. Biochemistry 31: 3777-85 (1992) Activated factor V (Va) serves as an essential protein cofactor for the conversion of prothrombin to thrombin by factor Xa. Analysis of the factor V cDNA indicates that the protein contains several types of internal repeats with the following domain structure: A1-A2-B-A3-C1-C2. In this report we describe the isolation and characterization of genomic DNA coding for human factor V. The factor V gene contains 25 exons which range in size from 72 to 2820 bp. The structure of the gene for factor V is similar to the previously characterized gene for factor VIII. Based on the aligned amino acid sequences of the two proteins, 21 of the 24 intron-exon boundaries in the factor V gene occur at the same location as in the factor VIII gene. In both genes, the junctions of the A1-A2 and A2-A3 domains are each encoded by a single exon. In contrast, the boundaries between domains A3-C1 and C1-C2 occur at intron-exon boundaries, which is consistent with evolution through domain duplication and exon shuffling. The connecting region or B domain of factor V is encoded by a single large exon of 2820 bp. The corresponding exon of the factor VIII gene contains 3106 bp. The 5' and 3' ends of both of these exons encode sequences homologous to the carboxyl-terminal end of domain A2 and the amino-terminal end of domain A3 in ceruloplasmin. There is otherwise no homology between the B domain exons.
First determination of the secondary structure of purified factor VIII light chain. Bihoreau N; Fontaine-Aupart MP; Lehegarat A; Desmadril M; Yon JM T.M. Innovation (Centre National de Transfusion Sanguine Institut Merieux), Les Ulis, France. Biochem J 288 ( Pt 1): 35-40 (1992) The first analysis of the secondary structure of human factor VIII light chain was performed by c.d. spectroscopy. The purification process described in this paper allowed us to obtain the large amounts of purified factor VIII light chains required for c.d. experiments. Since this 80 kDa protein is non-covalently associated with a heavy chain to form the active molecule, isolated factor VIII light chains were obtained after immunoadsorption and dissociation of the immobilized active complexes by EDTA. Furthermore, factor VIII light chains were discriminated from the residual active complexes and the free heavy chains by a final ion-exchange-chromatography step. This f.p.l.c. analysis showed that factor VIII light chains were less electronegative than the active complexes. The results of conformational analysis by c.d. show that the protein possesses a high degree of regular secondary structure (58%) with approx. 22% of alpha-helix and 36% of beta-strand structures. The protein was completely unfolded by 3 M-guanidine hydrochloride. The results obtained from the analysis of c.d. spectra were compared with those predicted from three different statistical methods based on amino-acid sequence. The secondary structure information obtained from these methods was in good agreement with the c.d. results. These results were comparable with the secondary structure prediction of ceruloplasmin, a protein known to show sequence identity to factor VIII.
Inhibition by serum components of oxidation and collagen-binding of low-density lipoprotein. Kalant N; McCormick S Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Canada. Biochim Biophys Acta 1128: 211-9 (1992) Low-density lipoprotein (LDL) is oxidized by cellular and noncellular mechanisms, both leading to an increased binding to collagen. We have investigated the effect of serum on lipid peroxidation, apoprotein oxidation and the binding of oxidized apoprotein to collagen. During noncellular oxidation, lipoprotein-deficient serum strongly inhibited all three processes. The serum fraction of M(r) > 100,000 was equally inhibitory; this effect was not due to alpha 1 or gamma globulins, alpha 2 macroglobulins, haptoglobins or ceruloplasmin. The serum fraction of M(r) 30,000-100,000 stimulated the binding of oxidized apoprotein but the albumin in this fraction inhibited lipid peroxidation and apoprotein oxidation. Serum ultrafiltrate (M(r) < 1000) inhibited lipid and protein oxidation, and binding; the inhibitory effect was abolished by deionization which removed histidine. The effects of lipoprotein-deficient serum and its fractions on cellular oxidation were similar but weaker than those on noncellular oxidation, HDL inhibited noncellular oxidation as well as binding of oxidized apoprotein. VLDL also inhibited oxidation; this could not be accounted for by its content of apo B. If present in vivo, these inhibitory effects would completely suppress both cellular and noncellular oxidation of LDL and its subsequent binding to collagen.
Molecular cloning of the gene for bilirubin oxidase from Myrothecium verrucaria and its expression in yeast. Koikeda S; Ando K; Kaji H; Inoue T; Murao S; Takeuchi K; Samejima T Tsukuba Research Laboratories, Amano Pharmaceutical Co., Ltd., Ibaragi, Japan. J Biol Chem 268: 18801-9 (1993) Myrothecium verrucaria bilirubin oxidase (EC 1.3.3.5) is an enzyme catalyzing the oxidation of bilirubin to biliverdin and other substrates. We have purified bilirubin oxidase from the medium of M. verrucaria and determined its partial amino acid sequence and isolated cDNA fragment amplified by polymerase chain reaction using oligonucleotide primers designed on the basis of the partial amino acid sequence. The gene for bilirubin oxidase has been cloned from a genomic library using the cDNA fragment as a probe. The gene encodes a precursor of bilirubin oxidase consisting of 572 amino acid residues, which comprises the prepro-region of 38 amino acid residues and the mature enzyme of 534 amino acid residues containing one cysteine. Five introns were found within the coding region. Sequence comparison of bilirubin oxidase with other blue copper proteins (laccase, ascorbate oxidase, human ceruloplasmin, plastocyanin, and azurin) revealed the presence of four domains corresponding to potential copper ligands. We have expressed this bilirubin oxidase gene in Saccharomyces cerevisiae under the repressible acid phosphatase promotor and found an active recombinant bilirubin oxidase, establishing the functional identity of the gene.
Molecular cloning, chromosomal mapping, and sequence analysis of copper resistance genes from Xanthomonas campestris pv. juglandis: homology with small blue copper proteins and multicopper oxidase. Lee YA; Hendson M; Panopoulos NJ; Schroth MN Department of Plant Pathology, University of California, Berkeley 94720. J Bacteriol 176: 173-88 (1994) Copper-resistant strains of Xanthomonas campestris pv. juglandis occur in walnut orchards throughout northern California. Four histidine-rich polypeptide regions in ORF1 and CopA strongly resembled the copper-binding motifs of small blue copper proteins and multicopper oxidases, such as fungal laccases, plant ascorbate oxidase, and human ceruloplasmin. Putative copper ligands of the ORF1 polypeptide product are proposed, indicating that the polypeptide of ORF1 might bind four copper ions: one type 1, one type 2, and two type 3.

Coenzyme Q10, plasma membrane oxidase and growth control.

Crane FL; Sun IL; Crowe RA; Alcain FJ; Low H Department of Biological Sciences, Purdue University, West Lafayette, IN 47907-1392, USA. Mol Aspects Med 15 Suppl: s1-11 (1994) The plasma membrane of eukaryotic cells contains an NADH oxidase which can transfer electrons across the membrane. This oxidase is controlled by hormones, growth factors and other ligands which bind to receptors in the plasma membrane. Oncogenes also affect activity of the oxidase. Natural serum components such as diferric transferrin and ceruloplasmin which stimulate proliferation also stimulate membrane oxidase activity. Additional growth factors can be required to complement the proliferative effect. Electron transport across the plasma membrane can be measured by the reduction of impermeable electron acceptors, such as ferricyanide, which also stimulate cell growth. The oxidants activate growth-related signals such as cytosolic alkalinization and calcium mobilization. Antiproliferative agents such as adriamycin and retinoic acid inhibit the plasma membrane electron transport. Flavin, Coenzyme Q and an iron chelate on the cell surface are apparent electron carriers for the transmembrane electron transport. Coenzyme Q10 stimulates cell growth, and Coenzyme Q analogs such as capsaicin and chloroquine reversibly inhibit both growth and transmembrane electron transport. The ligand-activated oxidase in the plasma membrane introduces a new basis for control of signal transduction in cells. The redox state of the quinone in the oxidase is proposed to control tyrosine kinase either by generation of H2O2 or redox-induced conformational change.

Synthesis and localization of plasma proteins in the developing human brain

.Mollgard K; Dziegielewska KM; Saunders NR; Zakut H; Soreq H 
Institute of Medical Anatomy A, University of Copenhagen, Denmark. 

Dev Biol 128: 207-21 (1988) 
The distribution and possible origins of plasma proteins in the human embryonic and fetal brain at different stages of development. As many as 23 plasma-like proteins have been identified in situ synthesis of these proteins (e.g., alpha-fetoprotein, alpha 1-antitrypsin, GC-globulin, alpha 2-macroglobulin, pseudocholinesterase, and transferrin) in some brain regions. The regional distribution of some proteins and the absence of some mRNAs suggest that the presence of certain plasma proteins in developing brain may be accounted for by uptake from csf or via nerve processes extending beyond the blood-brain barrier. In several cases, specific proteins appear to be associated with defined cell types, e.g., alpha-fetoprotein, GC-globulin, and ceruloplasmin with neurons, alpha 2-macroglobulin with endothelial cells, and ferritin with glial cellsa large number of plasma proteins in immature brain yet the blood-brain barrier to protein is present even at very early stages of brain development.

Evolution of blue copper proteins.

Ryden L 
Department of Biochemistry, Uppsala University, Sweden. 

Prog Clin Biol Res 274: 349-66 (1988) 
The evolutionary relationships of blue copper proteins are reviewed. Five homologous families of small blue proteins are recognized. Despite differences in length their peptide chains can all be accommodated into the eight-stranded fold of plastocyanin with some adjustments at three of the loops and the two termini. The C-termini of the blue oxidases ceruloplasmin and Neurospora laccase also fit into this fold and they are suggested to be homologous to the small blue proteins. The alignment of their amino acid sequences suggest some of the histidines to be binding active site copper. A superposition of the structures of poplar plastocyanin and bovine Cu-Zn superoxide dismutase (SOD) showed that 68 out of 99 alpha-carbons in plastocyanin overlapped with corresponding atoms in SOD with a rms distance of 2.99 A. In addition three of the histidine residues that were proposed to be copper-binding in laccase and ceruloplasmin aligned with ligands to the Cu-Zn pair in a SOD. Thus also SOD might be related to the blue proteins.

Atypical Menkes steely hair disease

Westman JA; Richardson DC; Rennert OM; Morrow G 3d 
Ohio State University College of Medicine, Department of Pediatrics, Columbus. 

Am J Med Genet 30: 853-8 (1988) 
Menkes steely hair disease (MSHD) is a rare disorder which typically results in severe mental retardation and death in early childhood. A 21-month-old boy with an atypical milder form was presented by Procopis et al. [1981].