ACVR2B Protein, Human/Cynomolgus (Biotinylated, HEK293, His-Avi)

ACVR2B, a transmembrane serine/threonine kinase, forms an activin receptor complex with activin type-1 serine/threonine kinase receptors (ACVR1, ACVR1B, or ACVR1c), playing a crucial role in transducing activin signals across the cell membrane and regulating various physiological and pathological processes. This includes influencing neuronal differentiation and survival, hair follicle development and cycling, FSH production by the pituitary gland, wound healing, extracellular matrix production, immunosuppression, and carcinogenesis. Activin, known to have a paracrine or autocrine role in ovarian follicular development, binds to the type-2 receptor at the plasma membrane, activating its serine-threonine kinase activity. This activated type-2 receptor then phosphorylates and activates the type-1 receptor, such as ACVR1B, leading to subsequent phosphorylation of the SMAD proteins SMAD2 and SMAD3. Once activated, SMAD2 and SMAD3, in association with the common partner SMAD4, translocate into the nucleus, where they mediate activin-induced transcription. The inhibitory SMAD7, recruited to ACVR1B through FKBP1A, can prevent the association of SMAD2 and SMAD3 with the activin receptor complex, blocking the activin signal. Furthermore, the binding of inhibin-B to the receptor, facilitated by the IGSF1 inhibin coreceptor, acts as an antagonist to activin signal transduction.