Pan-Genome Analysis of Gene Family and Functional Analysis of Genes in Cucumber.

Cucumbers are frequently affected by gray mold pathogen , a pathogen that causes inhibited growth and reduced yield. Jasmonic acid (JA) plays a primary role in plant responses to biotic stresses, and the jasmonate-ZIM-Domain (JAZ) proteins are key regulators of the JA signaling pathway. In this study, we used the pan-genome of twelve cucumber varieties to identify cucumber genes. Our findings revealed that two genes were present in all twelve cucumber varieties and showed no differences in protein sequence, gene structure, and motif composition. This suggests their evolutionary conservation across different cucumber varieties and implies that they may play a crucial role in cucumber growth. On the other hand, the other fourteen genes exhibited variations in protein sequence and gene structure or conserved motifs, which could be the result of divergent evolution, as these genes adapt to different cultivation and environmental conditions. Analysis of the expression profiles of the genes showed differential regulation by . Transient transfection plants overexpressing , , or were found to be more susceptible to infection compared to control plants. Furthermore, these plants infected by the pathogen showed lower levels of the enzymatic activities of POD, SOD and CAT. Importantly, after infection, the content of JA was upregulated in the plants, and cucumber cotyledons pretreated with exogenous MeJA displayed increased resistance to infection compared to those pretreated with water. Therefore, this study explored key genes in the regulation of cucumber growth and adaptability to different cultivation environments based on bioinformatics analysis and demonstrated that negatively regulate cucumber disease resistance to gray mold via multiple signaling pathways.