| Protein kinase PKN 1 associates with TRAF 2 and is involved in TRAF 2 NF kappaB signaling pathway . ^^^ In yeast two hybrid screening for PKN 1 binding proteins , we identified tumor necrosis factor alpha ( TNFalpha ) receptor associated factor 2 ( TRAF 2 ) . ^^^ FLAG tagged PKN 1 was co immunoprecipitated with endogenous TRAF 2 from HEK 293 cell lysate , and in vitro binding assay using the deletion mutants of TRAF 2 showed that PKN 1 directly binds to the TRAF domain of TRAF 2 . ^^^ PKN 1 has the TRAF 2 binding consensus sequences PXQX ( S / T ) at amino acid residues 580 584 ( PIQES ) , and P580AQ582A mutant was not co immunoprecipitated with TRAF 2 . ^^^ Furthermore , the reduced expression of PKN 1 by RNA interference ( RNAi ) down regulated TRAF 2 induced NF kappaB activation in HEK293T cells . ^^^ |