ACVR1B Antibody – Rabbit Polyclonal

This gene encodes an activin A type IB receptor. Activins are dimeric growth and differentiation factors which belong to the transforming growth factor-beta (TGF-beta) superfamily of structurally related signaling proteins. Activins signal through a heteromeric complex of receptor serine kinases which include at least two type I and two type II receptors. This protein is a type I receptor which is essential for signaling. Mutations in this gene are associated with pituitary tumors. Alternate splicing results in multiple transcript variants.

ALK4: Transmembrane serine/threonine kinase activin type-1 receptor forming an activin receptor complex with activin receptor type-2 (ACVR2A or ACVR2B). Transduces the activin signal from the cell surface to the cytoplasm and is thus regulating a many physiological and pathological processes including neuronal differentiation and neuronal survival, hair follicle development and cycling, FSH production by the pituitary gland, wound healing, extracellular matrix production, immunosuppression and carcinogenesis. Activin is also thought to have a paracrine or autocrine role in follicular development in the ovary. Within the receptor complex, type-2 receptors (ACVR2A and/or ACVR2B) act as a primary activin receptors whereas the type-1 receptors like ACVR1B act as downstream transducers of activin signals. Activin binds to type-2 receptor at the plasma membrane and activates its serine- threonine kinase. The activated receptor type-2 then phosphorylates and activates the type-1 receptor such as ACVR1B. Once activated, the type-1 receptor binds and phosphorylates the SMAD proteins SMAD2 and SMAD3, on serine residues of the C- terminal tail. Soon after their association with the activin receptor and subsequent phosphorylation, SMAD2 and SMAD3 are released into the cytoplasm where they interact with the common partner SMAD4. This SMAD complex translocates into the nucleus where it mediates activin-induced transcription. Inhibitory SMAD7, which is recruited to ACVR1B through FKBP1A, can prevent the association of SMAD2 and SMAD3 with the activin receptor complex, thereby blocking the activin signal. Activin signal transduction is also antagonized by the binding to the receptor of inhibin-B via the IGSF1 inhibin coreceptor. ACVR1B also phosphorylates TDP2. ACVRIB is abundantly expressed in systemic sclerosis patient fibroblasts and production of collagen is also induced by activin-A/INHBA. This suggests that the activin/ACRV1B signaling mechanism is involved in systemic sclerosis. Belongs to the protein kinase superfamily. TKL Ser/Thr protein kinase family. TGFB receptor subfamily. 5 isoforms of the human protein are produced by alternative splicing.

Protein type: Kinase, protein; Membrane protein, integral; Protein kinase, Ser/Thr (receptor); Protein kinase, TKL; EC 2.7.11.30; TKL group; STKR family; Type1 subfamily

Chromosomal Location of Human Ortholog: 12q13

Cellular Component: cell surface; integral to plasma membrane; plasma membrane; activin receptor complex; receptor complex

Molecular Function: transforming growth factor beta receptor activity; protein serine/threonine kinase activity; protein binding; activin receptor activity; activin receptor activity, type I; ubiquitin protein ligase binding; metal ion binding; growth factor binding; activin binding; SMAD binding; ATP binding; transmembrane receptor protein serine/threonine kinase activity; receptor signaling protein serine/threonine kinase activity

Biological Process: development of primary female sexual characteristics; central nervous system development; in utero embryonic development; protein amino acid autophosphorylation; positive regulation of erythrocyte differentiation; activin receptor signaling pathway; peptidyl-threonine phosphorylation; signal transduction; protein amino acid phosphorylation; positive regulation of activin receptor signaling pathway; hair follicle development; regulation of transcription, DNA-dependent; transmembrane receptor protein serine/threonine kinase signaling pathway; positive regulation of transcription from RNA polymerase II promoter; negative regulation of cell growth; G1/S transition of mitotic cell cycle