| Binding of CDK 9 to TRAF 2 . ^^^ In order to identify factors that contribute to CDK 9 ' s differentiation specific function , we screened a mouse embryonic library in the yeast two hybrid system and found a tumor necrosis factor signal transducer , TRAF 2 , to be an interacting protein . ^^^ CDK 9 interacts with a conserved domain in the TRAF C region of TRAF 2 , a motif that is known to bind other kinases involved in TRAF mediated signaling . ^^^ |