Abstract

Nuclei isolated from rat ventral prostate contain a number of messenger-dependent and -independent protein kinases. Studies were undertaken to determine the relative contribution of these protein kinases in phosphorylation of non-histone proteins (NHPs) in isolated nuclei. The data suggest that messenger-dependent protein kinases such as those dependent on cAMP or Ca2+/calmodulin or Ca2+/phospholipid may be present in very small amounts in intact isolated nuclei, and thus appear not to be significantly involved in phosphorylation of endogenous NHPs. Messenger-independent nuclear associated protein kinases PK-N1 and PK-N2 are known to catalyze the phosphorylation of NHPs in vitro (Goueli Sa, et al., Eur J Biochem 113: 45-51, 1980). Of these, the intrinsic heparin-sensitive PK-N2 as compared with heparin-insensitive PK-N1 appeared to be the predominant protein kinase engaged in phosphorylation of NHPs in intact nuclei. About 78-88% of NHP phosphorylation in intact nuclei was inhibited by heparin suggesting that the remaining 12-22% phosphorylation of NHPs was catalyzed via the heparin-insensitive protein kinase(s). Further, the data provide additional evidence that heparin-sensitive PK-N2 is the one that is most responsive to androgenic status in the animal.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.