Zusammenfassung der Gene: ACVR1B 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 ALK4 protein is a type I receptor which is essential for signaling. Mutations in ACVR1B gene are associated with pituitary tumors. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Jun 2010]General information above from NCBI
Katalytische Aktivität: ATP + [receptor-protein] = ADP + [receptor- protein] phosphate.
Cofactor: Magnesium or manganese (By similarity).
Enzymregulation: Activin receptor type-2 (ACVR2A or ACVR2B) activates the type-1 receptor through phosphorylation of its regulatory GS domain.
Untereinheitenstruktur: Forms an activin receptor complex with activin receptor type-2 (ACVR2A or ACVR2B). Interacts with TDP2 (By similarity). Interacts with AIP1, FKBP1A, IGSF1, TDGF1, SMAD2, SMAD3 and SMAD7.
Domäne: The GS domain is a 30-amino-acid sequence adjacent to the N-terminal boundary of the kinase domain and highly conserved in all other known type-1 receptors but not in type-2 receptors. The GS domain is the site of activation through phosphorylation by the II receptors.
Subzelluläre Position: Cell membrane; Single-pass type I membrane protein (By similarity).
Gewebespezifität: Expressed in many tissues, most strongly in kidney, pancreas, brain, lung, and liver.
Posttranslational: Autophosphorylated. Phosphorylated by activin receptor type-2 (ACVR2A or ACVR2B) in response to activin-binding at serine and threonine residues in the GS domain. Phosphorylation of ACVR1B by activin receptor type-2 regulates association with SMAD7.
Ubiquitinated. Level of ubiquitination is regulated by the SMAD7-SMURF1 complex.
Rolle bei der Krankheit: Note=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.
Sequenzähnlichkeit: Belongs to the protein kinase superfamily. TKL Ser/Thr protein kinase family. TGFB receptor subfamily.
Contains 1 GS domain.
Contains 1 protein kinase domain.C
General information above from UniProt