title: Changes in the activity and subcellular distribution of cyclic-AMP-dependent protein kinases with retinoic-acid-induced differentiation of embryonal carcinoma cells.
abstract: We investigated changes in the activity and subcellular distribution of cyclic-AMP-dependent protein kinases (cAMP-PKs) in response to treatment with retinoic acid in three different embryonal carcinoma cell lines derived from the same teratoma 6050. After retinoic-acid treatment, F9 and PCC4 cells gave rise to parietal-like endoderm, while PC13 cells differentiated into visceral endoderm. Retinoid treatment of F9 and PCC4 cells caused an increase in cAMP-PK activity as measured by histone phosphorylation, as well as increases in the amount of the RI and RII regulatory subunits of the cAMP-PKs, as quantitated by photoaffinity labeling with 8-azido-cyclic-32P-AMP, in both the soluble and plasma-membrane fractions. The increases in membrane cAMP-PK activity and RI and RII levels reached their maximum within 18 h of retinoid treatment, and then dropped to intermediate levels after 3 days of treatment. The cytosolic activity and the levels of the regulatory subunits exhibited a progressive increase during the 3 days of exposure to retinoic acid. The relative RI/RII ratios in the cytosol and membrane fractions of the treated cells were comparable to those found in established PYS-2 parietal-endoderm cells. PC13 stem cells had high levels of cAMP-PK activity and cAMP binding to the regulatory subunits in both the cytosol and plasma membranes, while also exhibiting very low levels of type-II cAMP-PK. Retinoid treatment induced a progressive increase in cAMP-PK activity in the cytosol, and a decrease in activity at the membrane level.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000345:Affinity Labels; D000818:Animals; D001386:Azides; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology; D000242:Cyclic AMP / Q000031:analogs & derivatives; D054278:Embryonal Carcinoma Stem Cells; D051379:Mice; D014411:Neoplastic Stem Cells / Q000201:enzymology* / Q000473:pathology; D011494:Protein Kinases / Q000378:metabolism*; D013347:Subcellular Fractions / Q000201:enzymology; D013724:Teratoma / Q000201:enzymology / Q000473:pathology; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D000345:Affinity Labels; D001386:Azides; C017042:8-azidoadenosine-3',5'-monophosphate; D014212:Tretinoin; D000242:Cyclic AMP; D011494:Protein Kinases