Vernalization-induced flowering in wheat is mediated by a lectin-like gene VER2

A vernalization-related gene VER2 was isolated from winter wheat (Triticum aestivum L.) using a differential screening approach. The deduced VER2 is a lectin-like protein of 300 amino acids, which contains the presence of a jacalin-like GWG domain. RNA in situ hybridization results demonstrated that VER2 gene expression is restricted to the marginal meristems of immature leaves in vernalized wheat seedlings. No hybridization signal was detected in the epidermal tissue and vascular bundles. However, 'devernalization' resulted in the silencing of VER2 gene activity. The gene expression pattern of VER2 induced by jasmonate was similar to that induced by vernalization. Antisense inhibition of VER2 in transgenic wheat showed that heading and maturation time were delayed up to 6 weeks compared with non-transformed wheat and the pBI121empty-vector-transformed wheat. Tissue degeneration at the top of the spike was also noticed in the antisense inhibited transgenic wheat. These results suggest that VER2 plays an important role in vernalization signaling and spike development in winter wheat.