signaling alliance facility at ut southwestern medical center dallas tex according to standard procedures phapi open reading frame orf was amplified by pcr from image clone aa488559 incyte genomics inc palo alto calif using primers cggcagatctctggatccatggagatgggcagacggattc seq id no 1 and cgccgtcgacttagtcatcatcttctccctc seq id no 2 the amplified product was subcloned into bamhi sali sites of pet 28a vector novagen milwaukee wis the plasmid was used to express recombinant his tagged phapi in bl21 de3 strain and the protein was purified using nta agarose qiagen valencia calif followed by q sepharose chromatography prot orf was amplified by pcr from image clone b315161 incyte using primers ccggcatatgtcagacgcagccgtagac seq id no 3 and ccggctcgaggtcatcctcgtcggtcttctg seq id no 4 the amplified product was subcloned into ndei xhoi sites of pet 21b vector novagen the plasmid was used to express recombinant his tagged prot in bl21 de3 strain and the protein was purified using nta agarose qiagen valencia calif followed by q sepharose chromatography double strand sirna ucaccaccaaggacuuaaa seq id no 5 corresponding to a region of prot mrna with dtdt overhead in 3 u2032 ends was synthesized by dharmacon lafayette colo to disrupt prot mrna in hela cells double stranded sirna gcagcacgacuucuucaagu seq id no 6 3 u2032 end dtdt overheads corresponding to a region.