Abstract
Class III peroxidases (PODs) are plant-specific enzymes that play crucial roles in plant growth, development and responses to stress. However, the POD gene family in the radish (Raphanus sativus L.) has not been comprehensively investigated to date. In this study, a total of 95 RsPODs were identified in the radish genome, which were classified into six subgroups based on a phylogenetic analysis. The gene structures and conserved motifs of the RsPODs were highly conserved within each subgroup. An intraspecific collinearity analysis revealed 7 tandem and 40 segmental duplication events. An expression analysis across diverse tissues and developmental stages demonstrated that the RsPODs were functionally involved in radish development. Using a chimeric-colored radish mutant, this study revealed significantly higher POD activity in the green tissues compared to purple tissues. Through transcriptome sequencing, two RsPOD genes (RsPOD14 and RsPOD28) were identified as candidate genes related to the anthocyanin metabolism. Our study provides a genome-wide perspective on the RsPOD genes in the radish and highlights their potential roles in the anthocyanin metabolism. These findings establish a critical foundation for future research aimed at uncovering the functional roles of specific RsPOD genes, with a particular emphasis on elucidating the molecular mechanisms that regulate anthocyanin degradation in the radish.