TAB1 Protein, Human

TAB1, a pivotal adapter protein, assumes a central role in the activation of JNK and NF-kappa-B, as well as the production of proinflammatory cytokines in response to TLRs and cytokine stimulation. Mechanistically, TAB1 associates with the catalytic domain of MAP3K7/TAK1, instigating MAP3K7/TAK1 autophosphorylation and ensuing full activation. This association also extends to MAPK14, triggering its autophosphorylation and activation. Intriguingly, MAPK14, in turn, phosphorylates TAB1, instigating a feedback control mechanism that inhibits MAP3K7/TAK1 activation. TAB1's involvement in recruiting MAPK14 to the TAK1 complex, where it phosphorylates the regulatory subunits TAB2 and TAB3, further underscores its regulatory role. Additionally, TAB1 interacts with XIAP and BIRC7, contributing to its intricate network of molecular associations. Notably, TAB1 engages with TRAF6 and MAP3K7 during IL-1 signaling, forming essential interactions that mediate downstream signaling events. Identified as part of the TRIKA2 complex, comprising MAP3K7, TAB1, and TAB2, TAB1's multifaceted interactions highlight its significance in orchestrating intricate signaling cascades.