Integration of seasonal flowering time responses in temperate cereals

Abstract

Our paper describes how the genetic pathways which regulate vernalization and long-day flowering responses are integrated to promote spring flowering in cereals. This process is mediated by the VERNALIZATION1 (VRN1) and VRN2 genes. VRN2 encodes a CONSTANS-like protein that represses FLOWERING LOCUS T (FT1) to block the long-day flowering response until plants are vernalized. When plants are vernalized VRN1, a FRUITFUL-like MADS box transcription factor, is induced. This downregulates VRN2, allowing long-day induction of FT1 to occur post-vernalization. A comparison of the pathways regulating seasonal induction of flowering in cereals with those of Arabidopsis shows the vernalization response pathway has evolved convergently to regulate the activity of a conserved daylength response pathway in these divergent plant lineages. ©2008 Landes Bioscience.