GSE158852
Genome-wide analysis of VlbZIP30-targeted genes involved in drought responses in grapevine (Vitis vinifera)
Drought stress dramatically affects the growth and development of grapevine (Vitis vinifera) in many areas of the world, and identifying the mechanisms responsible for drought stress responses is therefore of great interest. The transcription factor, VlbZIP30 has been reported to enhance drought resistance in grapevine, however, the regulatory mechanisms mediated by VlbZIP30 remain poorly understood. Here, we performed chromatin immunoprecipitation (ChIP)-seq and RNA-seq analyses to identify the direct VlbZIP30 target genes at a genome-wide scale. The ChIP-seq analysis determined that VlbZIP30 binds to DNA sequences containing an ACGTG core motif, termed a G-box. By combining the ChIP-seq and RNA-seq results, we identified 48 VlbZIP30-induced target genes, related mainly to the gene ontology (GO) terms: nucleic acid-templated transcription, plant hormone and abiotic stimulus. Through ChIP-qPCR analysis, we confirmed that VlbZIP30 binds directly to the promoters of four of the target genes (VvNAC26, VvDHN1, VvGRAS17 and VvVQ6) containing a G-box motif. In addition, overexpression of VlbZIP30 led to less H2O2 accumulation compared with the wild type under drought conditions in both Arabidopsis thaliana and grapevine, indicating a role for VlbZIP30 in reactive oxygen species (ROS) scavenging. In summary, we report that VlbZIP30 promotes the activity of ROS scavenging by directly regulating the expression of downstream target genes, thereby conferring drought resistance. We also reveal that VlbZIP30 directly regulates the expression of a number of target genes (such as VvDHN1, VvGRAS17 and VvVQ6) to improve plant drought resistance. Overall design: ChIP-seq assay of 4-month-old overexpression VlbZIP30 transgenic grape grown under drought stress for 20 days