Molecular aspects of soluble guanylyl cyclase regulation

Soluble guanylyl cyclase (sGC) is a heterodimeric enzyme (comprised of alph a and beta subunits) that generates the intracellular second messenger cycl ic guanosine monophosphate (cGMP) from guanosine triphosphate (GTP), cGMP i s subsequently important for the regulation of protein kinases, ion channel s, and phosphodiesterases. Since recent evidence has demonstrated that hete rodimerization of the alpha/beta subunits is essential for basal and stimul ated enzymatic activity, the existence of several types of isoforms for eac h of the two subunits, along with their varying degrees of expression in di fferent tissues, implies that multiple regulatory mechanisms exist for sGC. Yet, progress in studying and clarifying the regulatory processes that can alter sGC expression and activity has only slowly started being elucidated In the following paper, we elaborate on sGC structure, function, and distr ibution along with recently described signaling pathways that modulate sGC gene expression. (C) 2000 Elsevier Science Inc. All rights reserved.