IRAK1

IRAK1 (interleukin-1 receptor-associated kinase 1) transduces signals from the Toll-like receptor and IL-1 receptor families. Upon IL-1 binding or TLR engagement, IRAK1 is recruited to the adaptor MyD88 through death-domain interactions, phosphorylated by IRAK4 within the Myddosome, and then associates with TRAF6 to activate NF-κB and MAPK pathways. Unlike IRAK2 and IRAK3, IRAK1 is catalytically active and, after hyperphosphorylation, dissociates from the receptor complex and is degraded by the ubiquitin-proteasome system, a step that limits and shapes signaling duration. Hyperactive IRAK1 variants have been reported in autoimmune and oncogenic settings. Recombinant IRAK1 supports kinase assays, Myddosome reconstitution and inhibitor screening.