Fig 1.

Rhythmic regulation of gene expression in Arabidopsis cell culture. Suspension cells entrained under a 12:12 LD cycle for 2 days were transferred and sampled under LD (A), LL (B and C), or DD (D) for the time indicated (h) as ZT (A) or hours in LL (B and C), or in DD (D). Northern blots (A, B, and D) were probed for CCA1 and TOC1 (A and B) or CCR2 expression (D). Immunoblots (C) were probed for CCA1 abundance by using anti-CCA1 antiserum (22). White and black bars indicate light and dark periods, respectively; crosshatches in B and C indicate subjective dark; crosshatch in D indicates subjective light. Total RNA was used as loading controls in A, B, and D.