TBK1 Proteins and Enzymes

NFkappaB-activating kinase (NAK) also known as TANK binding kinase-1 (TBK1) or tumor necrosis factor receptor associated factor 2-associated kinase (T2K) is a serine/threonine protein that belongs to the IkB kinase (IKK) family (1). Similar to IKK alpha and beta (2), NAK induces IkB degradation and NF-kB activity. NAK is activated by phorbol ester tumour promoters and growth factors, whereas catalytically inactive NAK specifically inhibits activation of NF-kB by protein kinase C-epsilon (PKCepsilon). NAK specifically phosphorylates IkB alpha on Serine 36 and NFkB subunit RelA (p65) on Serine 536 (3). NAK is also known to interact with TANK, TRAF-2 and TRIF (4).