Effect of a diet low in methionine-cysteine on rat liver chromatin and nuclear proteins.
Rats were fed a diet low in methionine-cysteine for 6 days. One group was given the control diet after 6 days of methionine-cysteine restriction. Liver nuclei were isolated and incubated with 30 units DNA-A I (EC 3.1.4.5) per mg of DNA for 20 min. at 27 degrees C. The lysed nuclei were fractionated into a 1100 x g pellet P1 and a supernatant fraction S1. Protein distribution was analyzed by SDS-polyacrylamide gel electrophoresis. In the methionine-cysteine restricted group histone H1 relative to the other proteins was increased in the P2 fraction. Relative to the total content of histone H1 the subtype H1:2 was increased and H1(0) decreased. Refeeding the missing amino acids or pair-feeding of the rats gave results similar to the controls. On agarose gel electrophoresis, DNA of the P1 chromatin of the methionine-cysteine restricted rats migrated at a slower rate than that of the refed, pair-fed or control group, indicating a more compact structure of higher resistance to DNA-A I in the chromatin of the amino acid restricted rats. The results correlated with a diminished transcription activity in these animals. The alterations in the relative composition of histone H1 were the result of or the reason for the modulation in the chromatin structure observed after the restricted intake of the amino acids methionine-cysteine.
Norell
M
M
von der Decken
A
A
D000818:Animals; D002843:Chromatin / Q000187:drug effects / Q000378:metabolism*; D003545:Cysteine / Q000172:deficiency* / Q000494:pharmacology; D006657:Histones / Q000378:metabolism*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008715:Methionine / Q000172:deficiency* / Q000494:pharmacology; D009687:Nuclear Proteins / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values
D002843:Chromatin; D006657:Histones; D009687:Nuclear Proteins; D008715:Methionine; D003545:Cysteine