GUCY1B2

GUCY1B2 is a human gene encoding the beta-2 subunit of soluble guanylate cyclase (sGC), a key component of the nitric oxide (NO) signaling pathway. sGC is a heterodimer composed of a catalytic subunit pair—one alpha and one beta subunit—that together form an active enzyme responsive to NO and related stimuli.

The primary function of the sGC enzyme is to catalyze the conversion of guanosine triphosphate (GTP) to cyclic guanosine monophosphate (cGMP). cGMP acts as a second messenger that activates protein kinase G and other effectors, influencing processes such as vascular smooth muscle relaxation, inhibition of platelet aggregation, and modulation of neuronal signaling. The beta-2 subunit contributes to NO sensing via a heme-binding region and participates in forming the functional catalytic site through dimerization with an alpha subunit.

Expression of GUCY1B2 is observed in several tissues, with notable representation in vascular tissues and the central nervous system, though exact patterns can vary by species and context. The protein contains domains typical of sGC beta subunits, including regions involved in heme binding and catalytic activity, facilitating its role in assembling and regulating the heterodimeric enzyme.

Clinical relevance centers on the broader NO-sGC-cGMP signaling axis, which is implicated in cardiovascular regulation, blood pressure control, and thrombosis. While alterations in sGC signaling are linked to disease, the specific contribution of GUCY1B2 variants or expression changes to human disease remains an area of ongoing research.