Guanylate Cyclase Activator 2A (GUCA2A)

GUCA2; STARA; GCAP-I; Guanylin; Guanylate cyclase-activating protein 1

SPN	Q521
HGNC	4682
MGI	102738
RGD	2766
UniProt	Q02747

Binding of STa to STaR induces a dramatic increase in the cGMP content of the cell; the increase, in turn, inhibits salt absorption and stimulates chloride secretion. This imbalance of ions is accompanied by a massive accumulation of water in the gut that gives rise to the diarrhea and dehydration characteristic of enterotoxin activity. The identification of a receptor for STa on intestinal brush border membranes suggested the existence of an endogenous activator.

The sequences demonstrated that guanylin is present at the C-terminal end of a larger precursor protein. Expression in mammalian cells indicated that the 94-amino acid proguanylin is inactive. The biologically active guanylin can be released by either chemical or enzymatic treatment of proguanylin.

Reference

"Human guanylin: cDNA isolation, structure, and activity."
FEBS Lett. 311:150-154(1992) [PubMed] [Europe PMC] [Abstract]

"Precursor structure, expression, and tissue distribution of human guanylin."
Proc. Natl. Acad. Sci. U.S.A. 89:9089-9093(1992) [PubMed] [Europe PMC] [Abstract]

"Analysis of the human guanylin gene and the processing and cellular localization of the peptide."
Proc. Natl. Acad. Sci. U.S.A. 92:2046-2050(1995) [PubMed] [Europe PMC] [Abstract]

"The DNA sequence and biological annotation of human chromosome 1."
Nature 441:315-321(2006) [PubMed] [Europe PMC] [Abstract]

"The circulating bioactive form of human guanylin is a high molecular weight peptide (10.3 kDa)."
FEBS Lett. 318:205-209(1993) [PubMed] [Europe PMC] [Abstract]

"Determination of the solution structure of the peptide hormone guanylin: observation of a novel form of topological stereoisomerism."
Biochemistry 33:13581-13592(1994) [PubMed] [Europe PMC] [Abstract]

"Solution structure of human proguanylin: the role of a hormone prosequence."
J. Biol. Chem. 278:24118-24124(2003) [PubMed] [Europe PMC] [Abstract]