Activin B, Recombinant, Human, Active (Carrier Free)
Artikelnummer:
USB-A0855-93
Hersteller Artikelnummer:
A0855-93
Alternativnummer:
USB-A0855-93-10,USB-A0855-93-50
Hersteller:
US Biological
Kategorie:
Molekularbiologie
Activins and inhibins, members of the TGF-beta superfamily, are disulfide-linked dimeric proteins that were originally purified from gonadal fluids as proteins that stimulated or inhibited, respectively, pituitary follicle stimulating hormone (FSH) release. These proteins have since been shown to have a wide range of biological activities including: mesoderm induction, neural cell differentiation, bone remodeling, hematopoiesis and reproductive physiology. Activins/inhibins are produced as precursor proteins with an amino-terminal propeptide that is cleaved to release the carboxy-terminal bioactive ligands. Activins are homodimers or heterodimers of the various beta subunit isoforms, while inhibins are heterodimers of a unique alpha subunit and one of the various beta subunits. Five beta subunits (mammalian beta A, beta B, beta C, beta E and Xenopus beta D) have been cloned. The activin/inhibin nomenclature reflects the subunit composition of the proteins: activin A ( beta A - beta A), activin B ( beta B - beta B), activin AB ( beta A - beta B), inhibin A ( alpha - beta A) and inhibin B ( alpha - beta B). At present, little is known about the contribution of the other beta subunits to activin or inhibin formation and biology. At the amino acid sequence level, the mature human beta B subunit is greater than 98% identical to mouse beta B, while the human and mouse alpha subunits share approximately 80% identity. Similarly to other TGF-beta family members, activins exert their biological activities through binding to the heterodimeric complex composed of two membrane spanning serine-threonine kinases designated as type I and type II. Two forms of activin receptor type I (Act RI-A and Act RI-B) and two forms of activin receptor type II (Act RII-A and Act RII-B) have been identified. Activin binds directly to Act RII, the complex then associates with Act RI and initiates signaling. Besides activins, Act RII has been shown to bind certain other TGF-beta superfamily members. Inhibin A has been shown to bind with low-affinity to Act RII. The existence of a distinct inhibin-specific receptor and/or signal transduction pathway has been hypothesized. Recombinant protein corresponding to Gly293-Ala407 from human Activin, expressed in CHO cells. Swiss/Uniprot: P09529.2 N-terminal Sequence Analysis: Gly293 Predicted Molecular Mass: 13kD (monomer) SDS-PAGE: 10-13kD, under reducing conditions. Biological Activity: Measured by its ability to induce hemoglobin expression in K562 human chronic myelogenous leukemia cells. The ED50 for this effect is 0.2-4ng/ml. Storage and Stability: Lyophilized and reconstituted products are stable for 6 months after receipt at -20C. Reconstitute with sterile HCl. Aliquot to avoid repeated freezing and thawing. Store at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
