METHYLATION OF PROTEIN (HISTONE) IN VITRO - ENZYMIC ACTIVITY FROM SOLUBLE FRACTION OF RAT ORGANS

1. 1. An enzymic activity was found in the 150 000 × g supernatant fraction of rat organs capable of transferring methyl groups from [Me-14C]S-adenosyl-l-methionine to arginyl and lysyl residues of histones and some non-histone proteins. 2. 2. The best acceptors of methyl groups were found to be unfractionated histones of rat organs, calf thymus arginine-rich histones and poly-l-arginine. Among non-histone proteins, insulin and ribonuclease also served as acceptors. The enzymic activity showed no requirement for dialyzable factors. 3. 3. The same system was also found to be able to transfer acetyl groups from [14C]acetyl-CoA to histone, poly-l-arginine and poly-l-lysine. © 1969.