Circadian oscillation in Acetyl-CoA levels is controlled by the clock. Acetyl-CoA was extracted from mouse liver (A) or MEFs (B and C) harvested at indicated time points and analyzed by LC-MS/MS. A, relative abundance of acetyl-CoA in livers from WT and Clock−/− mice. ***, p = 0.00004 (WT ZT3 versus WT ZT21); **, p < 0.01 (WT ZT3 versus WT ZT 15); *, p < 0.05 (WT ZT3 versus WT ZT9); #, p < 0.05 (ZT3, WT versus CLOCK−/−); n = 4–7. Error bars, S.E. The total amount of acetyl-CoA (2200 pmol/μg DNA) was approximately 30% less in the Clock−/− liver at ZT3, compared with that in the WT liver (3200 pmol/μg DNA). B, acetyl-CoA levels in serum-entrained WT and Bmal1−/− MEFs. *, p < 0.05 (versus corresponding WT samples); **, p < 0.01 (versus WT 12 h); #, p < 0.05 (versus WT 24 h); n = 3. C, acetyl-CoA levels in serum-entrained WT MEFs treated with or without 50 μm EX527. *, p < 0.05 (versus control 12 h); n = 4.