The neural type II regulatory subunit of cAMP-dependent protein kinase is present and regulated by hormones in the rat ovary.
In this study purified isoforms of rat ovarian regulatory subunit of type II cAMP-dependent protein kinase (R-II) were compared with R-II purified from rat brain. A special neural form of R-II has been previously described in bovine brain. Analysis by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis resolved three isoforms of rat ovarian R-II (R-II54, Mr = 54,000; R-II52, Mr = 52,000; and R-II51, Mr = 51,000) compared to two R-II isoforms in rat brain (R-II54 and R-II52). Polychromatic silver-stained peptide maps of purified R-II subunits indicated that peptides generated from both rat ovarian R-II52 and R-II51 were similar (if not identical) to the peptides of the neural form, R-II52, purified from rat brain. These peptides differed markedly from those generated from R-II54 of either rat ovary, brain, or heart. Ovarian R-II52/51 photoaffinity labeled with 8-N3-[32P]cAMP and analyzed by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis was shown to consist of three (rather than two) isoelectric variants, which were similar to three variants resolved from rat brain R-II and clearly distinct from that of rat heart R-II54. An antibody which recognized both the R-II54 and R-II52/51 isoforms of rat ovarian extracts also recognized both forms of rat brain R-II (R-II54 and R-II52) and similar forms in extracts of rat adrenal and parotid glands. These results strongly suggest that the R-II52 isoform previously designated as a neural specific form of R-II is present in high concentrations in a nonneural tissue, the rat ovary.
D000818:Animals; D001921:Brain / Q000201:enzymology; D002352:Carrier Proteins / Q000302:isolation & purification* / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D007016:Hypophysectomy; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism; D009928:Organ Specificity; D010053:Ovary / Q000201:enzymology*; D011494:Protein Kinases / Q000378:metabolism; D051381:Rats
D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes; C015482:protein kinase modulator; D004958:Estradiol; D005640:Follicle Stimulating Hormone; D011494:Protein Kinases