Enhancement of 67LR expression by ATRA is mediated through RARα
RAR that binds to ligand ATRA form a heterodimer with RXRs and regulate the expression of specific genes [26], [27]. To investigate whether the ATRA-induced enhancement of 67LR expression is mediated through RARα, B16 cells were stably transfected with RARα shRNA expression vector that allows knockdown of RARα (Fig. 4A). Knockdown of RARα attenuated the ATRA-induced enhancement of 67LR expression (Fig. 4B). These results suggest that ATRA enhances 67LR expression through RARα.
10.1371/journal.pone.0011051.g004 Figure 4  ATRA enhances the 67LR expression via RARα.
A) RARα knockdown in B16 cells stably transfected with RARα shRNA expression vector was confirmed by Western blot analysis. B) B16 cells stably transfected with the control shRNA or the RARα shRNA expression vector were treated with or without 0.1 µM ATRA in DMEM supplemented with 1% FCS for 48 h. Levels of 67LR expression were analyzed by Western blot analysis and were normalized to β-Actin. Band intensities were quantified using NIH Image J software.