Analysis of the response regulatory network of pepper genes under hydrogen peroxide stress

Hydrogen peroxide (H O ) is a regulatory component related to plant signal transduction. To better understand the genome-wide gene expression response to H O stress in pepper plants, a regulatory network of H O stress-gene expression in pepper leaves and roots was constructed in the present study. We collected the normal tissues of leaves and roots of pepper plants after 40 days of H O treatment and obtained the RNA-seq data of leaves and roots exposed to H O for 0.5-24 h. By comparing the gene responses of pepper leaves and roots exposed to H O stress for different time periods, we found that the response in roots reached the peak at 3 h, whereas the response in leaves reached the peak at 24 h after treatment, and the response degree in the roots was higher than that in the leaves. We used all datasets for K-means analysis and network analysis identified the clusters related to stress response and related genes. In addition, , , and were identified through a co-expression analysis and were found to be strongly related to several reactive oxygen species-scavenging enzyme genes; their homologous genes in Arabidopsis showed important functions in response to hypoxia or iron uptake. This study provides a theoretical basis for determining the dynamic response process of pepper plants to H O stress in leaves and roots, as well as for determining the critical time and the molecular mechanism of H O stress response in leaves and roots. The candidate transcription factors identified in this study can be used as a reference for further experimental verification.