Flowering control mechanism of CO as a key factor in photoperiod pathway

CONSTANS (CO) gene plays a central role in the photoperiod pathway and it is one of the important components between circadian clock and flowering-time genes to measure the day-length. CO can integrate the signals of light and circadian clock, which can induce the expression of the flowering integrators FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), and then promotes to flower. This paper summarizes the flowering control mechanism of CO gene and also reviews the prospects of future researches according to present research status on CO gene.