The cis-elements responsible for Bmal1 transcription activation and repression are separated.
A, The d275 Bmal1-luc construct (WT), with a deletion from −77 to −118 (D118–77), or with both RORα-binding sites mutated (mRORE) was transfected into NIH 3T3 cells. Luciferase activity was measured 48 h later. B, WT, D118–77, or mRORE was transfected into NIH 3T3 cells and treated as in Fig. 1. C, WT, D118–77, or mRORE was co-transfected with NF-Y and/or Rev-Erbα into NIH 3T3 cells. Luciferase (Luc) activity was measured 48 h later. Error bars in A and C indicate mean ± S.E.