Activin receptor-like kinase 4 (ALK4) is a type I transmembrane glycoprotein, serine/threonine kinase, and member of the TGF-β superfamily that is encoded by ACVR1B in humans.1,2 It is composed of an extracellular ligand-binding domain, a single transmembrane domain, an intracellular serine/threonine kinase domain, and a cytoplasmic serine/threonine-rich region. ALK4 is ubiquitously expressed and forms heterodimers with activin receptor type IIA (ACTRIIA) or ACTRIIB at the cell surface. Upon ligand activation by activin A, activin B, activin AB, or Nodal, ALK4 is phosphorylated by its heterodimer partner and induces intracellular signaling and phosphorylation of SMAD2 and SMAD3 to regulate gene expression. ALK4-mediated signaling has roles in glucose-stimulated insulin secretion, neuronal differentiation of pluripotent stem cells, and the development of pancreatic and pituitary cancers.1,2,3 Cayman's ALK4 Extracellular Domain (human, recombinant) protein can be used for binding assays. This protein consists of 114 amino acids, has a calculated molecular weight of 13 kDa, and a predicted N-terminus of Ser24 after signal peptide cleavage. By SDS-PAGE, under reducing conditions, the apparent molecular mass of the protein is 18-20 kDa due to glycosylation.WARNING This product is not for human or veterinary use.
