CO-EXPRESSED WITH CLOCK GENES LHY AND CCA11 (CEC1) is regulated by LHY and CCA1 and plays a key role in phase setting of GI in Arabidopsis thaliana.

摘要

Many biological processes, including the control of flowering time, are regulated by the circadian clock. Although a number of clock-associated genes have been characterized in Arabidopsis thaliana (Arabidopsis), the complete molecular mechanisms of the circadian clock remain unclear. Here, we report that CO-EXPRESSED WITH CLOCK GENES LHY AND CCA1 1 (CEC1) plays an important role in circadian clock function in Arabidopsis. Three genes, CEC1, CEC2, and CEC3, are co-expressed with the clock genes LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK ASSOCIATED 1 (CCA1). The mutants, cec1 and cec2, exhibited an early flowering phenotype under long-day (LD) and continuous-light (LL) conditions, possibly through an increase in FLOWERING LOCUS T (FT) mRNA. In addition, rhythmic peaks of GIGANTEA (GI) expression were delayed in the cec1 mutant plants, but the period length and amplitude of GI expression were not affected under LD and LL. These results suggest that CEC1 might contribute to the modulation of circadian phases.