Tyrosine-Protein Kinase JAK1 (JAK1) Human Recombinant Protein

Janus kinase 1 (JAK1), is a member of a new class of protein-tyrosine kinases (PTK) characterized by the presence of a second phosphotransferase-related domain immediately N-terminal to the PTK domain. The second phosphotransferase domain bears all the hallmarks of a protein kinase, although its structure differs significantly from that of the PTK and threonine/serine kinase family members. JAK1 is a large, widely expressed membrane-associated phosphoprotein. JAK1 is involved in the interferon-alpha/beta and -gamma signal transduction pathways. The reciprocal interdependence between JAK1 and TYK2 activities in the interferon-alpha pathway, and between JAK1 and JAK2 in the interferon-gamma pathway, may reflect a requirement for these kinases in the correct assembly of interferon receptor complexes. These kinases couple cytokine ligand binding to tyrosine phosphorylation of various known signaling proteins and of a unique family of transcription factors termed the signal transducers and activators of transcription, or STATs. [provided by RefSeq, Jul 2008]

JAK1: a widely expressed non-receptor tyrosine-kinase involved in the interferon-alpha/beta and -gamma signal transduction pathways. Couples cytokine ligand binding to tyrosine phosphorylation of various known signaling proteins and of a unique family of transcription factors termed the signal transducers and activators of transcription, or STATs. A selective Jak1 inhibitor induces apoptosis in NRP-154 prostate cancer cell line. A single mutation seen in tyrosine kinome screen of colon cancers. Activated in B cell lines from patients with post-transplant lymphoproliferative disorder, and in a mouse Lck-driven T cell lymphoma. Inhibitor: Piceatannol.

Protein type: Protein kinase, TK; EC 2.7.10.2; Kinase, protein; Protein kinase, tyrosine (non-receptor); TK group; JakA family

Chromosomal Location of Human Ortholog: 1p32.3-p31.3

Cellular Component: cytoplasm; cytoskeleton; cytosol; endomembrane system; extrinsic to internal side of plasma membrane; focal adhesion; nucleus

Molecular Function: ATP binding; CCR5 chemokine receptor binding; growth hormone receptor binding; non-membrane spanning protein tyrosine kinase activity; protein binding; protein phosphatase binding; protein-tyrosine kinase activity; receptor binding; ubiquitin protein ligase binding

Biological Process: activation of MAPKK activity; axon guidance; cell differentiation; cell migration; cytokine and chemokine mediated signaling pathway; epidermal growth factor receptor signaling pathway; fibroblast growth factor receptor signaling pathway; innate immune response; insulin receptor signaling pathway; MAPKKK cascade; nerve growth factor receptor signaling pathway; protein amino acid phosphorylation; Ras protein signal transduction; regulation of cell proliferation; response to antibiotic; small GTPase mediated signal transduction; transmembrane receptor protein tyrosine kinase signaling pathway; vascular endothelial growth factor receptor signaling pathway