Protein phosphorylation reactions in chromatin from seminal vesicle epithelium
Norvitch, M.E.; Steer, R.C.; Wilson, M.J.; Ahmed, K.; Veneziale, C.M.
Cellular and Molecular Biology 29(3): 237-243
1983
ISSN/ISBN: 0145-5680 PMID: 6616529 Document Number: 197452
The general catalytic properties of protein kinase activity of chromatin isolated from the epithelium of guinea pig seminal vesicle are reported. Requirements were established for Mg2+, pH, ionic strength and ATP for the kinase reactions towards endogenous chromosomal proteins, as well as exogenous phosphate acceptor proteins (lysine-rich histone and dephosphophosvitin). Enzyme activity towards each substrate tested was unaffected by addition of 1 or 20 .mu.M cAMP or cGMP to the reaction mixture. Electrophoretic studies using polyacrylamide gels revealed specific differences in labeling of chromosomal proteins belonging to H2SO4-soluble and -insoluble non-histone protein fractions. Specific activities of the kinase reactions (nmol 32P/mg chromatin protein .times. h-1), were 2.9, 145.4 and 2.4, respectively, towards endogenous proteins, dephosphophosvitin and lysine-rich histone. The rate of incorporation of 32P from [.gamma.-32P]ATP into these substrates was markedly reduced in chromatin from animals killed 96 h following castration indicating that these reactions are controlled by androgenic status of the animals.