What are the function of activin and inhibin?

Activin and Inhibin are members of the TGF-beta superfamily of cytokines and are involved in a wide range of biological processes including tissue morphogenesis and repair, fibrosis, inflammation, neural development, hematopoiesis, reproductive system function, and carcinogenesis (1‑7). Activin and Inhibin are produced as precursor proteins.

How is the activity of activin A limited?

Intracellularly, the activity of activin A may be limited by Smad7 that inhibits the formation of an activated Smad complex. The activity and response to activin A are tightly modulated at several levels and this has been reviewed elsewhere (Chen et al., 2002; Rodgarkia-Dara et al., 2006 ).

What kind of homodimer is activin A?

Overview. Activin A is a member of the transforming growth factor beta (TGF-β) family of proteins produced by many cell types throughout development (Gurdon et al.). It is a disulfide-linked homodimer (two beta-A chains) that binds to heteromeric complexes of a type I (Act RI-A and Act RI-B) and a type II (Act RII-A and Act RII-B)…

How much EU per 1 μg of activin?

<0.01 EU per 1 μg of the protein by the LAL method. Measured by its ability to induce hemoglobin expression in K562 human chronic myelogenous leukemia cells. Schwall, R.H. et al. (1991) Method Enzymol. 198 :340. The ED 50 for this effect is 0.2‑1.2 ng/mL.

How is activin A related to the TGF-β superfamily?

Activin A is a member of the TGF-β superfamily, a large family of over 30 structurally related proteins (Piek et al., 1999). TGF-β superfamily cytokines play pivotal roles in regulation of tissue homeostasis, organ development, inflammation, cell proliferation, and apoptosis (de Caestecker, 2004; Ling et al., 1986).