INHBA explained

Inhibin, beta A, also known as INHBA, is a protein which in humans is encoded by the INHBA gene.^[1] INHBA is a subunit of both activin and inhibin, two closely related glycoproteins with opposing biological effects.

Function

The inhibin beta A subunit joins the alpha subunit to form a pituitary FSH secretion inhibitor. Inhibin has been shown to regulate gonadal stromal cell proliferation negatively and to have tumor-suppressor activity. In addition, serum levels of inhibin have been shown to reflect the size of granulosa-cell tumors and can therefore be used as a marker for primary as well as recurrent disease. Because expression in gonadal and various extragonadal tissues may vary several fold in a tissue-specific fashion, it is proposed that inhibin may be both a growth/differentiation factor and a hormone. Furthermore, the beta A subunit forms a homodimer, activin A, and also joins with a beta B subunit to form a heterodimer, activin AB, both of which stimulate FSH secretion. Finally, it has been shown that the beta A subunit mRNA is identical to the erythroid differentiation factor subunit mRNA and that only one gene for this mRNA exists in the human genome.^[2]

Interactions

INHBA has been shown to interact with ACVR2A.^{[3] [4]}

Further reading

• Munz B, Hübner G, Tretter Y, etal . A novel role of activin in inflammation and repair. . J. Endocrinol. . 161 . 2 . 187–93 . 1999 . 10320815 . 10.1677/joe.0.1610187 . free .
• Welt C, Sidis Y, Keutmann H, Schneyer A . Activins, inhibins, and follistatins: from endocrinology to signaling. A paradigm for the new millennium. . Exp. Biol. Med. (Maywood) . 227 . 9 . 724–52 . 2002 . 12324653 . 10.1177/153537020222700905. 19795772 .
• Shav-Tal Y, Zipori D . The role of activin a in regulation of hemopoiesis. . Stem Cells . 20 . 6 . 493–500 . 2003 . 12456957 . 10.1634/stemcells.20-6-493 . 36242096 . free .
• Reis FM, Luisi S, Carneiro MM, etal . Activin, inhibin and the human breast. . Mol. Cell. Endocrinol. . 225 . 1–2 . 77–82 . 2005 . 15451571 . 10.1016/j.mce.2004.02.016 . 24201803 .
• Shao L, Frigon NL, Young AL, etal . Effect of activin A on globin gene expression in purified human erythroid progenitors . Blood . 79 . 3 . 773–81 . 1992 . 1310063 . 10.1182/blood.V79.3.773.bloodjournal793773. free .
• Mathews LS, Vale WW . Expression cloning of an activin receptor, a predicted transmembrane serine kinase . Cell . 65 . 6 . 973–82 . 1991 . 1646080 . 10.1016/0092-8674(91)90549-E . 36407277 .
• Tanimoto K, Handa S, Ueno N, etal . Structure and sequence analysis of the human activin beta A subunit gene . DNA Seq. . 2 . 2 . 103–10 . 1992 . 1777673 . 10.3109/10425179109039678 .
• Mason AJ, Berkemeier LM, Schmelzer CH, Schwall RH . Activin B: precursor sequences, genomic structure and in vitro activities . Mol. Endocrinol. . 3 . 9 . 1352–8 . 1990 . 2575216 . 10.1210/mend-3-9-1352 . free .
• Barton DE, Yang-Feng TL, Mason AJ, etal . Mapping of genes for inhibin subunits alpha, beta A, and beta B on human and mouse chromosomes and studies of jsd mice . Genomics . 5 . 1 . 91–9 . 1989 . 2767687 . 10.1016/0888-7543(89)90091-8 . free .
• Murata M, Eto Y, Shibai H, etal . Erythroid differentiation factor is encoded by the same mRNA as that of the inhibin beta A chain . Proc. Natl. Acad. Sci. U.S.A. . 85 . 8 . 2434–8 . 1988 . 3267209 . 10.1073/pnas.85.8.2434 . 280011 . 1988PNAS...85.2434M . free .
• Burger HG, Igarashi M . Inhibin: definition and nomenclature, including related substances . Endocrinology . 122 . 4 . 1701–2 . 1988 . 3345731 . 10.1210/endo-122-4-1701 .
• Mason AJ, Niall HD, Seeburg PH . Structure of two human ovarian inhibins . Biochem. Biophys. Res. Commun. . 135 . 3 . 957–64 . 1986 . 3754442 . 10.1016/0006-291X(86)91021-1 .
• Stewart AG, Milborrow HM, Ring JM, etal . Human inhibin genes. Genomic characterisation and sequencing . FEBS Lett. . 206 . 2 . 329–34 . 1986 . 3758355 . 10.1016/0014-5793(86)81006-7 . 21261385 . free .
• Sumitomo S, Inouye S, Liu XJ, etal . The heparin binding site of follistatin is involved in its interaction with activin . Biochem. Biophys. Res. Commun. . 208 . 1 . 1–9 . 1995 . 7887917 . 10.1006/bbrc.1995.1297 .
• Xu J, McKeehan K, Matsuzaki K, McKeehan WL . Inhibin antagonizes inhibition of liver cell growth by activin by a dominant-negative mechanism . J. Biol. Chem. . 270 . 11 . 6308–6313 . 1995 . 7890768 . 10.1074/jbc.270.11.6308 . free .
• Mason AJ . Functional analysis of the cysteine residues of activin A . Mol. Endocrinol. . 8 . 3 . 325–32 . 1994 . 10.1210/mend.8.3.8015550 . 8015550 . 7615672 . free .
• Maruyama K, Sugano S . Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides . Gene . 138 . 1–2 . 171–4 . 1994 . 8125298 . 10.1016/0378-1119(94)90802-8 .
• Nishihara T, Okahashi N, Ueda N . Activin A induces apoptotic cell death . Biochem. Biophys. Res. Commun. . 197 . 2 . 985–91 . 1994 . 8267637 . 10.1006/bbrc.1993.2576 .
• ten Dijke P, Ichijo H, Franzén P, etal . Activin receptor-like kinases: a novel subclass of cell-surface receptors with predicted serine/threonine kinase activity . Oncogene . 8 . 10 . 2879–87 . 1993 . 8397373 .
• Tanimoto K, Yoshida E, Mita S, etal . Human activin betaA gene. Identification of novel 5' exon, functional promoter, and enhancers . J. Biol. Chem. . 271 . 51 . 32760–9 . 1997 . 8955111 . 10.1074/jbc.271.51.32760 . free .

Notes and References

1. Burger HG, Igarashi M . Inhibin: definition and nomenclature, including related substances . Endocrinology . 122 . 4 . 1701–2 . April 1988. 3345731 . 10.1210/endo-122-4-1701.
2. Web site: Entrez Gene: INHBA inhibin, beta A (activin A, activin AB alpha polypeptide).
3. Lewis . K A . Gray P C . Blount A L . MacConell L A . Wiater E . Bilezikjian L M . Vale W . March 2000. Betaglycan binds inhibin and can mediate functional antagonism of activin signalling . . 404 . 6776 . 411–4 . ENGLAND. 0028-0836. 10746731 . 10.1038/35006129 . 2000Natur.404..411L . 4393629 .
4. Martens . J W . de Winter J P . Timmerman M A . McLuskey A . van Schaik R H . Themmen A P . de Jong F H . July 1997. Inhibin interferes with activin signaling at the level of the activin receptor complex in Chinese hamster ovary cells . . 138 . 7 . 2928–36 . UNITED STATES. 0013-7227. 9202237 . 10.1210/endo.138.7.5250 . free .