Summary

Name ACVR1B
Full Name Activin receptor type-1B
Synonyms Activin receptor type IB, ACTR-IB, Activin receptor-like kinase 4, ALK-4, Serine/threonine-protein kinase receptor R2, SKR2 | ACVRLK4, ALK4
Primary ID P36896
Links - -
Type protein
Relations 12
Pathways Multiple sclerosis, Myostatin
Inhibitors SB 505124
Function 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.

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Modifications Tables

Relations

Regulator Mechanism target score
+ up-regulates activity img/direct-activation.png phosphorylation ACVR1B 0.672
Publications: 1 Organism: Homo Sapiens
Pathways:Multiple sclerosis
+ up-regulates activity img/direct-activation.png phosphorylation TDP2 0.287
Publications: 2 Organism: Homo Sapiens
+ up-regulates activity img/direct-activation.png binding ACVR1B 0.717
Publications: 1 Organism: Homo Sapiens
+ up-regulates activity img/direct-activation.png phosphorylation SMAD2 0.795
Publications: 2 Organism: Homo Sapiens, Mus Musculus
Pathways:Multiple sclerosis
+ down-regulates img/direct_inhibition.png chemical inhibition ACVR1B 0.8
Publications: 1 Organism: Homo Sapiens
+ up-regulates activity img/direct-activation.png binding ACVR1B 0.626
Publications: 1 Organism: Homo Sapiens
+ up-regulates img/direct-activation.png phosphorylation ACVR1B 0.667
Publications: 1 Organism: Homo Sapiens
Pathways:Multiple sclerosis
+ up-regulates activity img/direct-activation.png phosphorylation SMAD3 0.729
Publications: 1 Organism: Mus Musculus
Pathways:Multiple sclerosis
+ up-regulates quantity by stabilization img/indirect-activation.png HBA1 0.2
Publications: 1 Organism: Homo Sapiens
+ up-regulates quantity by stabilization img/indirect-activation.png HBB 0.2
Publications: 1 Organism: Homo Sapiens