The serine/threonine kinase IRAK (interleukin-1 receptor-associated kinase) is necessary for NF-kB activation. Under basal conditions, IRAK is not bound to the p75 receptor, and stays inactive in the cytoplasm. It associates with p75NTR following neurotrophin binding. MYD88 functions as an adapter, by recruiting IRAK to the p75 receptor. Upon stimulation with NGF, a MYD88: IRAK1 complex quickly forms that is recruited to p75NTR.