Synthesis and phosphorylation of histone H1 and high mobility group proteins in the regenerating rat liver after X irradiation.
A rat was irradiated to the upper abdomen including the liver and then partially hepatectomized. The subsequent synthesis and phosphorylation of histone H1 and nonhistone chromosomal high mobility group (HMG) proteins were investigated. Incorporation of [3H]lysine into histone H1 was increased and reached its peak at 27 h after hepatectomy, and 14 Gy of X rays inhibited the increase. Increase in the incorporation of [3H]lysine into HMG (1 + 2), 14, and 17 which occurred around 27 h after hepatectomy was not inhibited by 14 Gy irradiation. Phosphorylation of histone H1, measured with 32Pi incorporation in vivo, was maximal between 21 and 24 h, and it was inhibited by 4.8 Gy of X rays and delayed with 1.9 Gy. Phosphorylation of HMG 14, which was the only HMG protein phosphorylated under present conditions, was not affected by X irradiation. The [3H]thymidine incorporation into nuclear DNA started increasing at 21 h and reached its maximum at 27 h after hepatectomy. X irradiation with 4.8 Gy inhibited the incorporation, and 1.9 Gy lowered it.
D000818:Animals; D004247:DNA / Q000096:biosynthesis / Q000528:radiation effects; D004591:Electrophoresis, Polyacrylamide Gel; D006609:High Mobility Group Proteins / Q000096:biosynthesis* / Q000378:metabolism; D006657:Histones / Q000096:biosynthesis* / Q000378:metabolism; D008099:Liver / Q000528:radiation effects; D008115:Liver Regeneration / Q000528:radiation effects*; D008297:Male; D010766:Phosphorylation; D051381:Rats; D011919:Rats, Inbred Strains
D006609:High Mobility Group Proteins; D006657:Histones; D004247:DNA