TY - JOUR T1 - Effect of Testosterone on Nuclear Phosphoproteins of Rat Ventral Prostate JF - Molecular Pharmacology JO - Mol Pharmacol SP - 323 LP - 327 VL - 7 IS - 3 AU - KHALIL AHMED AU - HAJIME ISHIDA Y1 - 1971/05/01 UR - http://molpharm.aspetjournals.org/content/7/3/323.abstract N2 - 32P from [γ-32P]-ATP was rapidly incorporated into phosphoproteins of rat ventral prostate nuclei in vitro. At least 80% of the radioactivity (expressed per milligram of protein) was present in the non-histone phosphoproteins. The incorporation of 32P into phosphoproteins of nuclei isolated from orchiectomized rats was reduced greatly compared with nuclei isolated from orchiectomized rats treated with testosterone propionate or from normal control rats. The effect of testosterone on the incorporation in vitro of 32P from [γ-32P]-ATP into non-histone phosphoproteins of nuclei from castrated rats could be demonstrated as early as 30 min following a single injection of testosterone propionate. This effect could be explained in terms of increased activity of protein phosphokinase(s) in the nuclei. A possible role of nuclear protein phosphokinase(s) and the phosphorylation of non-histone phosphoproteins in the events related to the control of gene action in the prostate in response to testosterone is suggested. ACKNOWLEDGMENTS We thank Mr. C. Riggs for his help in these experiments. One of us (H. I.) wishes to thank the Fogarty International Center for the award of a Visiting Fellowship. ER -