FIG. 7.

Repression of the c-Myc oncogene, a downstream target of the β-catenin signaling pathway, by T3-bound TRβ but not by TRβPV. (A) Total RNA was prepared from FH-TRβ (bars 1 and 2), FH-TRβPV (bars 3 and 4), and FH (bar 5 and 6) cells cultured with (+) or without (−) T3 for 24 h and analyzed by real-time RT-PCR for c-Myc mRNA levels as described in Materials and Methods. (B) Whole-cell lysates from FH-TRβ cells (lanes 1 and 2), FH-TRβPV cells (lanes 3 and 4), or FH cells (control; lanes 5 and 6) cultured with (+) or without (−) T3 for 24 h were analyzed by Western blotting for c-Myc and PDI protein levels. In panel A, bars show means ± SEM for three to six samples. NS, not significant.