Effect of zinc status of rats on the synthesis and degradation of copper-induced metallothioneins.
Injection of Zn2+-adequate and Zn2+-deficient rats with Cu2+ stimulated the incorporation of l-[35S]cysteine into a low-molecular-weight Cu2+-binding protein in both liver and kidney. No significant incorporation of l-[4,5-3H]leucine into this protein occurred, confirming the previous claim that it was metallothionein and not some other leucine-rich protein. The half-life of the protein was found to be 16.9 +/- 1.0 (S.E.)h in the liver of Zn2+-adequate rats but only 12.3 +/- 0.5h in Zn2+-deficient animals. The degradation rate of the metallothionein was similar to the rate of disappearance of Cu2+ and Zn2+ from the protein, indicating that the release of mental from the protein and its catabolism occurred simultaneously. There was no significant difference in the half-lives of the hepatic or renal copper-thioneins in Zn2+-adequate rats.
D000818:Animals; D002850:Chromatography, Gel; D003300:Copper / Q000494:pharmacology*; D003545:Cysteine / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D006207:Half-Life; D007668:Kidney / Q000378:metabolism; D007930:Leucine / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D008667:Metalloproteins / Q000378:metabolism*; D008668:Metallothionein / Q000378:metabolism*; D051381:Rats; D015032:Zinc / Q000172:deficiency* / Q000378:metabolism
D008667:Metalloproteins; D003300:Copper; D008668:Metallothionein; D007930:Leucine; D015032:Zinc; D003545:Cysteine