Rabbit polyclonal antibody to GCS~α~1 (D423)

Guanylate cyclases belong to the adenylyl cyclase class~4/guanylyl cyclase family. There are two forms of guanylate cyclase, a soluble form (GCS or sGC), which act as receptors for nitric oxide and a membrane~bound receptor form (GC), which are peptide hormone receptors. The GC~C protein is composed of an extracellular domain, a single transmembrane domain, and a cytoplasmic region consisting of a kinase~like domain and a catalytic domain. It is expressed as two differentially glycosylated forms, a 130 kDa precursor form present in the endoplasmic reticulum and a 145 kDa form present on the plasma membrane. Ligand binding to the extracellular domain of GC~C promotes the accumulation of cGMP. GC~C acts as the receptor for heatstable enterotoxins, small peptides secreted by some pathogenic strains of E. coli that cause severe secretory diarrhea. GC~C also binds to guanylin and uroguanylin peptides, which modulate renal function in response to oral salt load.