The molecular mechanism of vernalization in Arabidopsis and cereals: role of Flowering Locus C and its homologs

Winter varieties of plants can flower only after exposure to prolonged cold. This phenomenon is known as vernalization and has been widely studied in the model plantArabidopsis thalianaas well as in monocots. Through the repression of floral activator genes, vernalization prevents flowering in winter. InArabidopsis,FLOWERING LOCUS CorFLCis the key repressor during vernalization, while in monocots vernalization is regulated throughVRN1,VRN2andVRN3(orFLOWERING LOCUS T). Interestingly,VRNgenes are not homologous toFLCbutFLChomologs are found to have a significant role in vernalization response in cereals. The presence ofFLChomologs in monocots opens new dimensions to understand, compare and retrace the evolution of vernalization pathways between monocots and dicots. In this review, we discuss the molecular mechanism of vernalization-induced flowering along with epigenetic regulations inArabidopsisand temperate cereals. A better understanding of cold-induced flowering will be helpful in crop breeding strategies to modify the vernalization requirement of economically important temperate cereals.