ACVR1B
ACVR1B (activin A receptor type 1B, also known as ALK4, SKR2, ActRIB and ACVRLK4) is a transmembrane serine/threonine kinase that acts as a type 1 activin receptor. It transduces the activin signal from the cell surface to SMAD proteins in the cytoplasm. Browse Assay Genie's current range of ACVR1B research reagents below, or read on for the biology behind the target.
ACVR1B forms an activin receptor complex with the type 2 receptors ACVR2A or ACVR2B. Activin binds the type 2 receptor at the plasma membrane and activates its serine-threonine kinase. The activated type 2 receptor then phosphorylates and activates the type 1 receptor, so ACVR1B acts as the downstream transducer while the type 2 receptors are the primary activin receptors. Once active, ACVR1B binds and phosphorylates SMAD2 and SMAD3 on serine residues of their C-terminal tails. These SMADs are released into the cytoplasm, interact with the common partner SMAD4, and the complex translocates to the nucleus to drive activin-induced transcription. ACVR1B also phosphorylates TDP2.
The signal is subject to negative control. Inhibitory SMAD7, recruited to ACVR1B through FKBP1A, can prevent SMAD2 and SMAD3 from associating with the receptor complex and so block signalling. Inhibin-B, acting through the IGSF1 inhibin coreceptor, also antagonises activin signal transduction by binding the receptor. Through this pathway ACVR1B regulates processes including neuronal differentiation and 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.
The ACVR1B gene belongs to the HGNC group of type 1 receptor serine/threonine kinases, and the protein is a member of the TKL Ser/Thr protein kinase family, TGFB receptor subfamily. Activins are dimeric growth and differentiation factors of the TGF-beta superfamily, and they signal through a heteromeric complex containing at least two type 1 and two type 2 receptors. ACVR1B is a type 1 receptor essential for this signalling. Mutations in the gene are associated with pituitary tumours, and alternative splicing produces multiple transcript variants. Mouse and rat orthologs are both named Acvr1b.
ACVR1B is the type 1 receptor that relays activin signals from type 2 receptors to SMAD2 and SMAD3, making it central to activin pathway studies.
The receptor regulates carcinogenesis-related processes, and mutations in the gene are associated with pituitary tumours, which makes it relevant to tumour biology.
Activin signalling through ACVR1B influences FSH production by the pituitary and is thought to act in ovarian follicular development.
ACVR1B signalling contributes to neuronal differentiation and survival, hair follicle development and cycling, wound healing and extracellular matrix production.
ACVR1B is a type 1 activin receptor kinase. After a type 2 receptor activates it, it phosphorylates SMAD2 and SMAD3, which join SMAD4 and move to the nucleus to drive activin-induced transcription. It also phosphorylates TDP2.
The HGNC name is activin A receptor type 1B, previously activin A receptor, type IB. Aliases and previous symbols include ALK4, SKR2, ActRIB and ACVRLK4. UniProt lists the protein as activin receptor type-1B, and alternative splicing yields multiple transcript variants.
Orthologs exist in mouse and rat, both named Acvr1b; check the datasheet of any product for its validated reactivity. In humans, mutations in the ACVR1B gene are associated with pituitary tumours, and the receptor is implicated in carcinogenesis more broadly.
Partner activin type 2 receptors and related type 1 receptor kinases of the TGF-beta family with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P36896; product specifications from Assay Genie datasheets.