Aliases for JAK3 Gene
External Ids for JAK3 Gene
Previous GeneCards Identifiers for JAK3 Gene
The protein encoded by this gene is a member of the Janus kinase (JAK) family of tyrosine kinases involved in cytokine receptor-mediated intracellular signal transduction. It is predominantly expressed in immune cells and transduces a signal in response to its activation via tyrosine phosphorylation by interleukin receptors. Mutations in this gene are associated with autosomal SCID (severe combined immunodeficiency disease). [provided by RefSeq, Jul 2008]
GeneCards Summary for JAK3 Gene
JAK3 (Janus Kinase 3) is a Protein Coding gene. Diseases associated with JAK3 include scid, autosomal recessive, t-negative/b-positive type and severe combined immune deficiency, autosomal recessive, t cell-negative, b cell-positive, nk cell-negative, jak3-related. Among its related pathways are PI3K-Akt signaling pathway and GPCR Pathway. GO annotations related to this gene include protein tyrosine kinase activity and non-membrane spanning protein tyrosine kinase activity. An important paralog of this gene is TNK1.
UniProtKB/Swiss-Prot for JAK3 Gene
Non-receptor tyrosine kinase involved in various processes such as cell growth, development, or differentiation. Mediates essential signaling events in both innate and adaptive immunity and plays a crucial role in hematopoiesis during T-cells development. In the cytoplasm, plays a pivotal role in signal transduction via its association with type I receptors sharing the common subunit gamma such as IL2R, IL4R, IL7R, IL9R, IL15R and IL21R. Following ligand binding to cell surface receptors, phosphorylates specific tyrosine residues on the cytoplasmic tails of the receptor, creating docking sites for STATs proteins. Subsequently, phosphorylates the STATs proteins once they are recruited to the receptor. Phosphorylated STATs then form homodimer or heterodimers and translocate to the nucleus to activate gene transcription. For example, upon IL2R activation by IL2, JAK1 and JAK3 molecules bind to IL2R beta (IL2RB) and gamma chain (IL2RG) subunits inducing the tyrosine phosphorylation of both receptor subunits on their cytoplasmic domain. Then, STAT5A AND STAT5B are recruited, phosphorylated and activated by JAK1 and JAK3. Once activated, dimerized STAT5 translocates to the nucleus and promotes the transcription of specific target genes in a cytokine-specific fashion.
JAKs (or Janus kinases) are a family of tyrosine kinases that associated with cytokine receptors. Upon receptor activation JAKs phosphorylate the transcription factors known as STATs and initiate the JAK-STAT signaling pathway. Four JAK family members have been identified (JAK1, JAK2, JAK3 and Tyk2), which share a similar protein domain structure: a kinase domain, a regulatory pseudo -kinase domain, a SH2 domain and a FERM domain. The FERM domain of JAK family members mediates the association of JAK with other enzymes and cytokine receptors. The JAK Tyk2 associates with the IFN-1, IL-6, 10, 12, and 23 cytokine receptor families. JAK1 mediates signals from IFN-alpha, beta, gamma and IL-2, 6 receptors. JAK2 transduces signals from the single chain and IL-3 cytokine receptor families, and from the IFN-gamma receptors. JAK3 associates with the IL-2 receptor gamma-chain.