Genome-Wide Identification and Characterization of Annexin Gene Family in Vitis vinifera and Functional Analysis of VvANN8 Under Salt Stress.

Grapes are economically significant fruit trees cultivated globally, but they are often affected by various abiotic stresses. Plant annexins are a class of calcium-dependent phospholipid-binding proteins that play crucial roles in regulating plant growth, development, and stress responses. However, the functions of grape annexins (VvANNs) remain relatively poorly understood. In this study, a total of 21 VvANNs were identified from the grape genome and categorized into six groups based on phylogenetic analysis. The conserved domains, motifs, cis-acting elements, and gene structures of VvANNs were further analyzed. Moreover, real-time quantitative polymerase chain reaction (RT-qPCR) analysis was performed; most VvANNs exhibited significant up-regulation when grape plantlets were treated with polyethylene glycol (PEG), cold, ABA, and salt stress. Given that VvANN8 was significantly up-regulated under salt stress, we selected VvANN8 for further investigation; results showed that the expression of VvANN8 in Arabidopsis enhanced salt tolerance by regulating reactive oxygen species (ROS) accumulation. This study provides a valuable foundation for the in-depth understanding of the VvANN gene family and comprehensively reveals the crucial role of VvANN8 in responding to salt stress.