ALK-4 (Activin Receptor-Like Kinase 4) or ACVR1B (Activin A Receptor; type 1B); belongs to the protein kinase superfamily; TKL Ser/Thr protein kinase family; and TGFB receptor subfamily. ALK-4/ACVR1B acts as a transducer of activin or activin like ligands signals. Activin binds to either ACVR2A or ACVR2B and then forms a complex with ACVR1B. The known type II activin receptors include ActRII and ActRIIB; while the main type I activin receptor in mammalian cells is ALK-4 (ActRIB). In the presence of activin; type II and type I receptors form complexes whereby the type II receptors activate ALK-4 through phosphorylation. The activated ALK-4; in turn; transduces signals downstream by phosphorylation of its effectors; such as Smads; to regulate gene expression and affect cellular phenotype. ALK-4/ACVR1B is an important regulator of vertebrate development; with roles in mesoderm induction; primitive streak formation; gastrulation; dorsoanterior patterning; and left-right axis determination.
Measured by its binding ability in a functional ELISA. Immobilized human TDGF1 at 2 µg/ml (100 ?l/well) can bind human ALK-4 with a linear range of 0.0068-0.16 µg/ml.
Endotoxin:
<1.0 EU per µg as determined by the LAL method.
Protein Construction:
A DNA sequence encoding the human ACVR1B (NP_004293.1) extracellular domain (Met 1-Glu 126) was fused with C-terminal His-tagged Fc region of human IgG1 at the C-terminus.
Purity:
> 80 % as determined by reducing SDS-PAGE.
Mol Mass:
39.6 kDa
AP Mol Mass:
46 kDa
Formulation:
Lyophilized from sterile PBS; pH 7.4
Shipping:
This product is provided as lyophilized powder which is shipped with ice packs.
Stability and Storage:
Lyophilized proteins are stable for up to 12 months when stored at -20 to -80°C. Reconstituted protein solution can be stored at 4-8°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.
