Invitrogen™ JAK3 Monoclonal Antibody (5H2)

Janus kinase 3 (JAK3) phosphorylates members of the STAT (signal transduction and activators of transcription) family. JAK3 is predominantly expressed in immune cells and transduces a signal in response to activation of interleukin receptors. In response to a varitety of cytokine or related factors (e.g., interferon, interleukins), JAKs are activated via phosphorylation at 2 adjacent tyrosine residues. The activation of JAKs can lead to the phosphorylation of STAT (signal transducers and activatiors of transcription) proteins, which dimerize and translocate to the nucleus. Once translocated to the nucleus, the STAT proteins can modify transcription of numerous genes, including interferon-stimulated genes. JAK2 is required for the IFN gamma-receptor complex initiation and JAK1 functions as an amplifier. However, active JAK1 may be required for complex responses. Some studies have suggested that the role of JAK2 might be performed by Tyk2 and JAK3, if they were positioned correctly within the IFN gamma-receptor complex.