Abstract
Copper accumulates in kidney tissue of mottled (Mo) mice largely in association with a low MW cytosol protein, and the reduced copper levels in neonatal mutant liver are largely the result of a reduction in the amount of copper associated with this same protein. On the basis of ion-exchange chromatographic profile, heat stability, absence of a 280nm absorption peak, and the binding of Cd109 and Zn65 the protein mutants in the kidney is identified as metallothionein (MT). Amino acid analysis, however, failed to confirm this, and it is suggested that the high copper content of the mutant protein results in its oxidative degradation during purification, even when normal anaerobic precautions are taken. Estimates of thionein protein content of tissues from mutant and normal mice demonstrated that the levels are significantly elevated in both young and adult mutant kidney and depressed in young mutant liver, in parallel therefore with the changes in tissue copper levels. In adult mutant liver tissue, however, thionein levels are significantly raised, even though tissue copper content is normal. The synthesis and degradation of MT was examined in some detail. Incorporation of S35-cysteine in kidney MT was significantly raised in both young and adult mutant mice, while in adult tissue the rate of degradation of MT was significantly depressed. The elevated kidney MT levels arise therefore in young mutant mice from an increased rate of synthesis and in adult mice from the combined effects of increased synthesis and reduced degradation. The degradation of kidney MT was followed in young mice by the loss of Zn65. A biphasic decay curve was revealed in both mutant and normal tissue. The results support the conclusion that the Mo disorder primarily affects copper homeostasis and are consistent with the presence of a lesion in cellular copper efflux in copper-accumulating tissues. The changes in MT levels are a direct result of the altered intra-cellular concentrations.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Beratis, N. G., Price, P., LaBadie, G., and Hischhorn, K. (1978). 64Cu metabolism in Menkes and normal cultured skin fibroblasts. Pediat. Res. 12699.
Bremner, I., Hoekstra, W. G., Davies, N. T., and Young, B. W. (1978). Effect of zinc status of rats on the synthesis and degradation of copper-induced metallothioneins. Biochem. J. 174883.
Cain, K., and Holt, D. E. (1979). Metallothionein degradation: Metal composition as a controlling factor. Chem-Biol. Interact. 2891.
Camakaris, J., Danks, D. M., Ackland, L., Cartwright, E., Borger, P., and Cotton, R. G. H. (1980). Altered copper metabolism in cultured cells from human Menkes' syndrome and mottled mouse mutants. Biochem. Genet. 18117.
Cherian, M. G., and Goyer, R. A. (1978). Metallothioneins and their role in the metabolism and toxicity of metals. Life Sci. 231.
Danks, D. M., Campbell, P. E., Stevens, B. J., Mayne, V., and Cartwright, E. (1972). Menkes' kinky-hair syndrome. An inherited defect in copper absorption with wide-spread effects. Pediatrics 50188.
Davis, B. J. (1964). Disc electrophoresis. II. Method and application to human serum proteins. Ann. N.Y. Acad. Sci. 121404.
Diezel, W., Kopperschläger, G., and Hoffman, E. (1972). An improved procedure for protein staining in polyacrylamide gels with a new type of Coomassie brilliant blue. Anal. Biochem. 48617.
Feldman, S. L., and Cousins, R. J. (1976). Degradation of hepatic zinc-thionein after parenteral zinc administration. Biochem. J. 160583.
Goka, T. E., Stevenson, R. E., Hefferman, P. M., and Howell, R. R. (1976). Menkes' disease: A biochemical abnormality in cultured human fibroblasts. Proc. Natl. Acad. Sci. USA 73604.
Hartmann, H. J., and Weser, U. (1977). Copper-thionein from fetal bovine liver. Biochim. Biophys. Acta 491211.
Holstein, T. J., Fung, R. Q., Quevedo, W. C., Jr., and Bienieki, T. C. (1979). Effect of altered copper metabolism induced by mottled alleles and diet on mouse tyrosinase (40662). Proc. Soc. Exp. Biol. Med. 162264.
Horn, N. (1976). Copper incorporation studies on cultured cells for prenatal diagnosis of Menkes' disease. Lancet 11156.
Hunt, D. M. (1974). Primary defect in copper transport underlies mottled mutants in the mouse. Nature (Lond.) 249852.
Hunt, D. M. (1976). A study of copper treatment and tissue copper levels in the murine congenital copper deficiency, Mottled. Life Sci. 191913.
Hunt, D. M. (1977). Catecholamine biosynthesis and the activity of a number of copperdependent enzymes in the copper deficient mottled mouse mutants. Comp. Biochem. Physiol. 57C79.
Hunt, D. M. (1980). Copper and neurological function. In Biological Roles of Copper Ciba Foundation Symposium Vol. 79, Excerpta Medica, Amsterdam, pp. 247–260.
Hunt, D. M., and Port, A. E. (1979). Trace element binding in the copper deficient mottled mutants in the mouse. Life Sci. 241453.
Johnson, W. T., and Evans, G. W. (1980). Isolation of a (copper, zinc)-thionein from the small intestine of neonatal rats. Biochem. Biophys. Res. Comm. 9610.
Minkel, D., Poulson, K., Wieglus, S., Shaw, C., and Petering, D. (1980). On the sensitivity of metallothioneins to oxidation during isolation. Biochem. J. 191475.
Moore, S. (1963). On the determination of cystine as cysteic acid. J. Biol. Chem. 238235.
Port, A. E., and Hunt, D. M. (1979). A study of copper-binding proteins in liver and kidney tissue of neonatal normal and mottled mutant mice. Biochem. J. 183721.
Prins, H. W., and Van den Hamer, C. J. A. (1981a). Degradation of 35S-labeled metallothionein in the liver and the kidney of brindled mice: Model for Menkes' disease. Life Sci. 282953.
Prins, H. W., and Van den Hamer, C. J. A. (1981b). Comparative studies of copper metabolism in liver and kidney of normal and mutated Brindled mice—with special emphasis on metallothionein. Comp. Biochem. Physiol. 70C255.
Rowe, D. W., McGoodwin, E. B., Martin, G. R., and Grahn, D. (1977). Decreased lysyl oxidase activity in the aneurysm-prone, mottled mouse. J. Biol. Chem. 252939.
Ryden, L., and Deutsch, H. F. (1978). Preparation and properties of the major copper-binding component in human fetal liver. Its identification as metallothionein. J. Biol. Chem. 253519.
Tsunoo, H., Kino, K., Nakajima, H., Hata, A., Huang, I-Y, and Yoshida, A. (1978). Mouse liver metallothioneins. Purification, molecular weight, amino acid composition, and metal content. J. Biol. Chem. 2534172.
Author information
Authors and Affiliations
Additional information
This work was supported by an MRC project grant. Amino acid analyses were performed by Dr J. Hastings, Chester Beatty Research Institute, Fulham Road, London SW3 6JB, U.K. The excellent technical assistance of Mr G. Puddefoot is gratefully acknowledged.
Rights and permissions
About this article
Cite this article
Hunt, D.M., Clarke, R. Metallothionein and the development of the mottled disorder in the mouse. Biochem Genet 21, 1175–1194 (1983). https://doi.org/10.1007/BF00488469
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00488469