Li Shuwen

Highlight: Integration of ATAC-seq and RNA-seq identifies novel candidate genes associated with drought tolerance in Zoysia japonica Steud. The warm-season turfgrass Zoysia japonica is renowned for its drought resistance and serves as an exceptional domestic turfgrass in China. In order to unlock the potential of this native grass, identify drought-resistant genes, enhance the genetic transformation system, and maximize its utilization benefits, we conducted physiological characterization, multi-omics analysis, and RT-qPCR experimental verification in Zoysia japonica. This study suggested that 63 high-confidence genes related to drought stress and 6 motifs regulating drought responses were identified using a combined omics approach and RT-qPCR validation. The study discovered a positive correlation between ATAC-Seq peak intensity and gene expression levels. The expression of high-confidence genes was linked to Zoysia japonica resistance evaluation and phenotypic traits, implying that these genes are involved in responding to external drought stress. This study combined ATAC-seq and RNA-seq technologies for the first time to identify drought-related genes in Zoysia japonica , elucidating the grass’s adaptation to environmental stress and the regulatory mechanisms underlying stress responses, and laying the groundwork for Zoysia japonica improvement and breeding.

The TGACG motif-binding factor1 (TGA1) transcription factor, a significant protein in the bZIP transcription factor family, exhibits a myriad of functions, contributes to numerous biological events, and holds substantial application potential. In this study, our analysis revealed a diverse range of photoregulatory and hormone regulatory elements within the MtTGA1 promoter region. The expression profile of MtTGA1 indicated its highest expression in the root, with its regulation influenced by SA, ABA, BR, and GA. Under salt stress conditions, transgenic plants demonstrated significantly longer root lengths and heightened activities of antioxidant enzymes such as ascorbic acid catalase (APX), peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) in their roots and leaves compared to control plants. Simultaneously, the levels of endogenous hormones ABA and BR escalated in transgenic plants, with a marked change in the morphology of their leaf cells. Transcriptome analysis identified a total of 193 differentially expressed genes, implicating a wide array of biological processes. Furthermore, we found that MtTGA1 is able to interact with Medicago truncatula SPX domain containing protein 1 (SPX1). In conclusion, the MtTGA1 transcription factor plays a crucial role in enhancing salt tolerance, which provides new insights for improving plant survival under salt stress conditions.