Epigenetic repression and resetting of a floral repressor, FLC, in the life cycle of winter-annual Arabidopsis

Plants have established highly sensitive systems to sense environmental cues and optimize their development accordingly. Long-term cold exposure in winter elicits flowering in many biennial and perennial plants, which is termed vernalization. Vernalized plants transition from the vegetative stage in winter to the reproductive stage in the subsequent spring season. In terms of molecular mechanisms, vernalization promotes floral transition by repressing floral repressor genes [i.e., FLOWERING LOCUS C (FLC)] that prevent plant bolting. Recent intensive studies enhanced our understanding of the mechanisms underlying the epigenetic suppression of FLC as well as resetting vernalization requirements in the next generation. This review describes recent advances in our understanding of vernalization-triggered epigenetic repression and resetting events of a floral repressor, FLC, in the lifecycle of winter-annual Arabidopsis.