Transcriptome analysis of two pepper genotypes infected with pepper mild mottle virus

Area of Science:

• Plant Pathology
• Molecular Biology
• Genomics

Background:

• Pepper mild mottle virus (PMMoV) is a highly contagious and persistent pathogen threatening pepper production.
• Limited understanding exists regarding the molecular mechanisms of plant responses to PMMoV.

Purpose of the Study:

• To investigate the molecular basis of pepper's response to PMMoV infection.
• To identify candidate genes and pathways conferring resistance or susceptibility to PMMoV.

Main Methods:

• RNA sequencing was performed on tolerant (17-p63) and susceptible (16-217) pepper genotypes post-PMMoV inoculation.
• Differential gene expression analysis, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and Weighted Gene Co-expression Network Analysis (WGCNA) were employed.

Main Results:

• Significant differences in viral accumulation and symptom development were observed between tolerant and susceptible genotypes.
• Thousands of differentially expressed genes (DEGs) were identified, with notable enrichment in MAPK signaling, plant-pathogen interaction, and flavonoid biosynthesis pathways.
• WGCNA identified modules and seven hub genes associated with PMMoV resistance.

Conclusions:

• The study reveals crucial insights into pepper's defense mechanisms against PMMoV.
• Candidate genes and pathways involved in virus resistance have been identified, offering potential targets for breeding resistant pepper varieties.