All thermal cycling conditions were 1 cycle of 3 min at 95 _C (initial denaturation) followed by 30 cycles of 30 s at 95 _C, 30 s at 60 _C, 1 min at 72 _C, with a final extension step of 7 min at 72 _C. The amplified fragment was cloned into pGEMT-easy vector, digested with the HindIII and BamHI restriction enzymes, and inserted into above pCMV-MCS-BGHpA vector, resulting in pCMV-TRAF2-BGHpA.