# CaCBP2 Negatively Regulates Pepper Resistance to Phytophthora capsici Infection

## TL;DR

This study identifies CaCBP2 as a protein that weakens peppers' resistance to a specific plant disease, offering new insights for crop breeding.

## Contribution

The study reveals CaCBP2 as a novel negative regulator of pepper resistance to Phytophthora capsici.

## Key findings

- CaCBP2 expression is significantly induced by Phytophthora capsici infection.
- CaCBP2 negatively regulates pepper resistance to Phytophthora capsici.
- CaCBP2 may influence immune responses through antioxidant systems and hormone metabolism.

## Abstract

Research on the CBP gene family in plants is scarce, with only sporadic reports on its association with immune responses. No systematic study has explored how CBP family genes regulate pepper resistance against Phytophthora capsici. Here, we focused on pepper CaCBP2, an RNA-binding protein, whose expression was significantly induced by P. capsici. Functional validation via VIGS and heterologous overexpression confirmed CaCBP2 as a negative regulator of pepper resistance to P. capsici. Based on physiological assays, transcriptome sequencing and WGCNA, we speculate it may mediate immune responses by regulating antioxidant systems, defense hormone metabolism, and disease resistance-related genes. Our findings fill the relevant research gap, enrich the role of RNA-binding proteins in plant anti-phytophthora defense, and provide a novel target for crop disease-resistant breeding.