Oligodeoxynucleotides antisense to mRNA encoding protein kinase A, protein kinase C, and beta-adrenergic receptor kinase reveal distinctive cell-type-specific roles in agonist-induced desensitization.
The roles of three protein kinases, cyclic AMP-dependent protein kinase (protein kinase A), protein kinase C, and beta-adrenergic receptor kinase (beta ARK), implicated in agonist-induced desensitization of guanine nucleotide-binding protein (G-protein)-coupled receptors were explored in four different cell lines after 48 hr of incubation with oligodeoxynucleotides antisense to the mRNA encoding each kinase. Desensitization of beta 2-adrenergic receptors was analyzed in cell types in which the activities of the endogenous complement of protein kinases A and C and beta ARK were distinctly different. Protein kinase A was necessary for desensitization of rat osteosarcoma cells (ROS 17/2.8), whereas the contribution of beta ARK to desensitization was insignificant. In Chinese hamster ovary cells that stably express beta 2-adrenergic receptors and in smooth muscle cells (DDT1MF-2), oligodeoxynucleotides antisense to beta ARK mRNA nearly abolished desensitization, whereas oligodeoxynucleotides antisense to protein kinase A mRNA attenuated desensitization to a lesser extent. In human epidermoid carcinoma cells (A-431), oligodeoxynucleotides antisense to either protein kinase A mRNA or beta ARK mRNA attenuated agonist-induced desensitization, providing a third scenario in which two kinases constitute the basis for agonist-induced desensitization. In sharp contrast, oligodeoxynucleotides antisense to protein kinase C mRNA were found to enhance rather than attenuate desensitization in DDT1MF-2 and A-431 cell lines, demonstrating counterregulation between prominent protein kinases in desensitization. Using antisense oligodeoxynucleotides to "knock out" target protein kinases in vivo, we reveal distinctive cell-type-specific roles of protein kinase A, protein kinase C, and beta ARK in agonist-induced desensitization.
Shih
M
M
Department of Molecular Pharmacology, School of Medicine, State University of New York, Stony Brook 11794-8651.
Malbon
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CC
D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000096:biosynthesis*; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D008969:Molecular Sequence Data; D009130:Muscle, Smooth; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D012516:Osteosarcoma; D011493:Protein Kinase C / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D018343:Receptors, Adrenergic, beta-2 / Q000187:drug effects / Q000502:physiology; D014162:Transfection; D014407:Tumor Cells, Cultured; D014649:Vas Deferens; D051552:beta-Adrenergic Receptor Kinases
D016376:Oligonucleotides, Antisense; D012333:RNA, Messenger; D018343:Receptors, Adrenergic, beta-2; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D051552:beta-Adrenergic Receptor Kinases; D007545:Isoproterenol