FIG. 8.

RET2A-Flag mutant exerts a dominant negative effect over an activated RET2A. (A) Western blot analysis of equivalent protein extracts from cells transfected with the RET2A and RET2A-Flag expression vectors alone (lanes 1 and 2) or together at three different molar ratios (lanes 3 to 5). The RET forms were stained with anti-RET antibodies. The migration of the 170- and 150-kDa RET monomers is indicated. (B and C) Transactivation-cotransfection assay performed with the TRE-TK-CAT plasmid (2 μg) as the reporter, the RET2A carrying vector as the transactivator at a 1:3 ratio (6 μg), and the RET2A-Flag (B)- or HSCR32 (C)-containing plasmid in three molar ratios with respect to RET2A plasmid (6, 12, and 18 μg). An empty vector was used as the negative control of the experiments. CAT activity is reported as relative induction and represents the mean of at least three independent experiments performed with different DNA preparations. The standard deviation is indicated by error bars. +, species is present; −, species is absent.