Regulation of Flowering by Vernalisation in Arabidopsis

Plants have evolved several mechanisms to control flowering time in response to environmental and endogenous signals. In particular, changes in temperature and day length throughout the year provide plants with clues to sense seasonal changes. Many plants in temperate climates respond to a long-term cold temperature of winter to be competent to flower in the following spring, a process known as vernalisation. In Arabidopsis, FLOWERING LOCUS C (FLC) is a major floral repressor that inhibits floral integrator genes and is subject to the epigenetic repression by vernalisation. Therefore, the stable repression of FLC by vernalisation permits plants to flower when inductive day length is achieved in spring. The epigenetic repression of FLC by vernalisation includes multiple levels of gene regulation ranging from chromatin modifications to non-coding RNAs. Here, we describe the current understanding of the molecular basis of vernalisation in Arabidopsis.