(A) TaqMan real-time RT-PCR of cDNA was performed with liver whole-cell RNA for the transcripts of Dbp, endogenous Rev-erbα, mCry1, mCry2, mPer1, and mPer2 from untreated LAP-tTA/TRE-Rev-erbα mice (solid lines; −Dox) and Dox-treated LAP-tTA/TRE-Rev-erbα mice (dotted lines; +Dox).
(B) Western blot analysis of liver nuclear extracts from LAP-tTA/TRE-Rev-erbα mice that were fed with normal chow (−Dox) or Dox-treated chow (+Dox). In accordance with the temporal mRNA profiles shown in (A) and (B), mCRY1 and mPER1 display reduced levels in untreated mice, whereas mPer2 and mCry2 accumulate to similar levels in nuclei of Dox-treated and untreated animals. The varying mPER1 migration is probably due to oscillating protein phosphorylation and dephosphorylation (see [18]).