Cyclic-AMP-dependent protein kinase (PKA) in testicular cells. Cell specific expression, differential regulation and targeting of subunits of PKA

LH and FSH regulate via cyclic adenosine 3'5' cyclic monophosphate (cAMP) a nd cAMP-dependent protein kinase (PKA), steroid biosynthesis is Leydig and Sertoli cells, respectively. Cyclic AMP also regulates a number of differen t cellular processes such as cell growth and differentiation, ion channel c onductivity, synaptic release of neurotransmitters, and gene transcription. The principle intracellular target for cAMP in mammalian cells is the PKA. The fact that this broad specificity protein kinase mediates a number of d iscrete physiological responses following cAMP engagement, has raised the q uestion of how specificity is maintained in the cAMP/PKA system. Here we de scribe features of this signaling pathway that may contribute to explain ho w differential effects of cAMP may be contributed to features of the PKA si gnaling pathway. (C) 1999 Elsevier Science Ltd. All rights reserved.