Histone variant H2A.Z is required for plant salt response by regulating
gene transcription
Abstract
As a well-conserved histone variant, H2A.Z epigenetically regulates
plant growth and development as well as the interaction with
environmental factors. However, the role of H2A.Z in response to salt
stress remains unclear, and whether nucleosomal H2A.Z occupancy work on
the gene responsiveness upon salinity is obscure. Here, we elucidate the
involvement of H2A.Z in salt response by analyzing H2A.Z disorder plants
with impaired or overloaded H2A.Z deposition. The salt tolerance is
dramatically accompanied by H2A.Z deficiency and reacquired in H2A.Z OE
lines. H2A.Z disorder changes the expression profiles of large-scale of
salt responsive genes, announcing that H2A.Z is required for plant salt
response. Genome-wide H2A.Z mapping shows that H2A.Z level is induced by
salt condition across promoter, TSS and TES (-1 kb to +1kb), the peaks
preferentially enrich at promoter regions near TSS. We further show that
H2A.Z deposition within TSS provides a direct role on transcriptional
control, which has both repressive and activating effects, while it is
found generally H2A.Z enrichment negatively correlate with gene
expression level response to salt stress. This study shed light on the
H2A.Z function in salt tolerance, highlighting the complex regulatory
mechanisms of H2A.Z on transcriptional activity for yielding appropriate
responses to particularly environmental stress.