Dexamethasone-induced phosphorylation of high mobility group nonhistone proteins of aging rats.
Phosphorylation of high mobility group (HMG) proteins and its modulation by dexamethasone were examined in vitro by incubating liver slices of young (15-) and old (138-week) male rats with (32P) orthophosphate. HMG proteins were extracted and analyzed by acid-urea polyacrylamide gel electrophoresis. Phosphorylation of HMG proteins, particularly of HMG2, 14 and 17 decreases drastically in old rats. Dexamethasone stimulates the phosphorylation of total HMG proteins in both ages. Individual HMG proteins vary in the extent of 32P incorporation. Such differential phosphorylation of HMG proteins and its modulation by dexamethasone may affect chromatin organization and gene expression during aging.
Department of Zoology, Banaras Hindu University, Varanasi, India.
S
S
Prasad
M K
MK
Thakur
D000367:Age Factors; D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology*; D006609:High Mobility Group Proteins / Q000378:metabolism*; D008297:Male; D010766:Phosphorylation; D051381:Rats; D011919:Rats, Inbred Strains
D006609:High Mobility Group Proteins; D003907:Dexamethasone