Fig. 5. CAT activities were assayed in COS cells transiently transfected with the RET1-CAT reporter construct (A) together with Rax or RaxL expression vectors (B) or with combinations of different ratios of expression vectors as indicated (C). The CAT activity from each transfection was normalized for internal transfection efficiency (see Materials and Methods). The relative CAT activity was normalized to the value from empty vector (B) or from RaxL transfection alone (C). The data presents the average value of triplicates. EnRax^* represents EnRaxC, EnRaxLC or EnRaxLHD indicated in C.