From Wikipedia, the free encyclopedia
| Activin receptor type-1 |
| Other names: |
Activin receptor type I, ACTR-I, Serine/threonine-protein kinase, receptor R1, SKR1, Activin receptor-like kinase 2, ALK-2, TGF-B superfamily receptor type I, TSR-I |
| Genetic data |
| Gene code: |
HUGO code:ACVR1 |
| Protein Structure/Function |
| Protein type: |
Serine/Threonine receptor kinase |
| Domains: |
GS domain, TS domain, S/T domain |
| Other |
| Taxa expressing: |
Homo sapiens; homologs: many metazoan phyla |
| Cell types: |
ubiquitous |
| Subcellular localization: |
Plasma membrane |
| Enzymatic Data |
| Catalytic activity: |
ATP + (receptor-protein) = ADP + (receptor-protein) phosphate |
| Cofactor(s): |
Magnesium or manganese |
| Medical/Biotechnological data |
| Diseases: |
Fibrodysplasia ossificans progressiva (FOP) Mendelian Inheritance in Man (OMIM) 135100 |
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The Activin type I receptors transduce signals for a variety of members of the Transforming growth factor beta superfamily of ligands. This family of cytokines and hormones inlude activin, Anti-müllerian hormone (AMH), bone morphogenetic proteins (BMPs), and Nodal. They are involved in a host of physiological processes including, growth, cell differentiation, homeostasis, osteogenesis, apoptosis and many other functions.There are three type I Activin receptors:ACVR1, ACVR1B, and ACVR1C Each bind to a specific type II receptor-ligand complex.
Despite the large amount of processes that these ligands regulate, they all operate through essentially the same pathway: A ligand binds to a Type two receptor, which recruits and trans-phosphorylate a type I receptor. The type I receptor recruits a receptor regulated SMAD (R-SMAD) which it phosphorylates. The RSMAD then translocates to the nucleus where it functions as a transcription factor.
ACVR1 or ALK-2 tranduces signals of BMPs. BMPs bind either ACVR2A/ACVR2B or a BMPR2 and then forms a complex with ACVR1. These go on to recruit the R-SMADs SMAD1, SMAD2, SMAD3 or SMAD6[1] .
[edit] ACVR1B
ACVR1B or ALK-4 acts as a transducer of Activin or activin like ligands (eg. Inhibin) signals. Activin binds to either ACVR2A or ACVR2B and then forms a complex with ACVR1B. These go on to recruit the R-SMADs SMAD2 or SMAD3[1]. ACVR1B also transduces signals of nodal, GDF-1, and Vg1; however, unlike activin, they require other coreceptor molecules such as the protein Cripto[2].
[edit] ACVR1C
ACVR1C or ALK-7 transduces signals of Nodal. Nodal binds to ACVR2B and then forms a comlex with ACR1C. These go on to recruit the R-SMADs SMAD2 or SMAD3[1].
[edit] References
- ^ a b c Inman, GJ, Nicolas FJ, Callahan JF, Harling JD, Gaster LM, Reith AD, Laping NJ, Hill CS. (Jul 2002). "SB-431542 is a potent and specific inhibitor of transforming growth factor-beta superfamily type I activin receptor-like kinase (ALK) receptors ALK4, ALK5, and ALK7". Mol Pharmacol. 62 (1). Entrez PubMed 12065756. Retrieved on 2006-07-05.
- ^ Harrison, CA, Gray PC, Koerber SC, Fischer W, Vale W (Jun 2003). "Identification of a functional binding site for activin on the type I receptor ALK4". J Biol Chem. 278 (23). Entrez PubMed 12665502. Retrieved on 2006-07-05.
