Histone variant H2A.Z and transcriptional activators may antagonistically regulate flavonoid biosynthesis

Abstract

Flavonoid is an important group of plant secondary metabolites. The biosynthesis of this flavonoid group can be precisely regulated by many environmental factors. Currently, histone variants have been documented as important factors in the regulation of eukaryotic gene expression. H2A.Z histone variant has been found to function in numerous plant physiological programs including flavonoid biosynthesis. Moreover, the environmental changes have been shown to significantly influence the replacement between histone proteins and their variants leading to alterations in gene expression. Based on the recent studies, this mini-review is to provide an updated view on the functions of histone variant H2A.Z in the regulation of flavonoid biosynthetic gene expression. In addition, this also suggests a model in which the H2A.Z-containing nucleosomes can be evicted upon environmental stress conditions to facilitate the targeting of transcriptional activators to these flavonoid biosynthetic genes resulting in gene activation and flavonoid accumulation in Arabidopsis plants.