Background Pythium myriotylum Drechsler is considered to be one of the pathogens of mung bean (Vigna radiata (L.) R. Wilczek) root rot, which threatens the yield of V. radiata. Pathogenesis-related protein 1 (PR1) is an important plant defense protein against various stressors. However, the role of PR1 in V. radiata resistance to P. myriotylum remains largely unknown. Results In this study, we identified six PR1 family members containing the conserved CAPE1 (CAP-derived peptide 1) domain (PxGNxxxxxPY) through bioinformatic analysis of the V. radiata genome. VrPR1 expression was significantly induced after P. myriotylum infection in V. radiata plants, and three candidate genes (VrPR1-3, VrPR1-4, and VrPR1-6) were selected to investigate their molecular characteristics and roles in resistance to P. myriotylum. Subcellular localization analysis showed that these three PR1 proteins (VrPR1-3, VrPR1-4, and VrPR1-6) were localized to the extracellular space when ectopically expressed in Nicotiana benthamiana Domin leaves. VrPR1-3, VrPR1-4, and VrPR1-6 enhanced resistance to P. myriotylum, as demonstrated using Nicotiana benthamiana transient overexpression and V. radiata hairy root transformation systems. Actually, Transient overexpression of VrPR1-6 in Nicotiana benthamiana conferred enhanced resistance against P. myriotylum compared to the overexpression of VrPR1-3 or VrPR1-4. Further functional analysis using the Nicotiana benthamiana transient overexpression system indicated that the resistance conferred by PR1 depends on the C-terminal CAPE1 domain of VrPR1-6 protein. Furthermore, a comparative transcriptome analysis of hairy roots overexpressing VrPR1-6 and GFP showed that "plant-pathogen interaction" pathway genes, including 10 genes related to the Ca2+ signaling pathway, were upregulated. Conclusions This study revealed that overexpression of VrPR1-3, VrPR1-4 and VrPR1-6 enhanced the resistance of V. radiata to P. myriotylum. Among them, the resistance of VrPR1-6 depends on the C-terminal CAPE1 domain and may involve Ca2 + -mediated signaling. These findings establish a foundation for further research into the immune defense pathways of V. radiata against P. myriotylum.

Functional evaluation of pathogenesis-related protein-1 (PR1) genes in mung bean (Vigna radiata) response to Pythium myriotylum

期刊论文
出版模式：

开放获取
发表日期：

2025年11月4日

查看全文

Yanyan Zhou,
Yuting Chen,
Xinyue Liu,
Dong Xue,
Yu Zheng,
Xingxing Yuan,
Qiang Yan,
Xin Chen

摘要

Background

Pythium myriotylum Drechsler is considered to be one of the pathogens of mung bean (Vigna radiata (L.) R. Wilczek) root rot, which threatens the yield of V. radiata. Pathogenesis-related protein 1 (PR1) is an important plant defense protein against various stressors. However, the role of PR1 in V. radiata resistance to P. myriotylum remains largely unknown.

Results

In this study, we identified six PR1 family members containing the conserved CAPE1 (CAP-derived peptide 1) domain (PxGNxxxxxPY) through bioinformatic analysis of the V. radiata genome. VrPR1 expression was significantly induced after P. myriotylum infection in V. radiata plants, and three candidate genes (VrPR1-3, VrPR1-4, and VrPR1-6) were selected to investigate their molecular characteristics and roles in resistance to P. myriotylum. Subcellular localization analysis showed that these three PR1 proteins (VrPR1-3, VrPR1-4, and VrPR1-6) were localized to the extracellular space when ectopically expressed in Nicotiana benthamiana Domin leaves. VrPR1-3, VrPR1-4, and VrPR1-6 enhanced resistance to P. myriotylum, as demonstrated using Nicotiana benthamiana transient overexpression and V. radiata hairy root transformation systems. Actually, Transient overexpression of VrPR1-6 in Nicotiana benthamiana conferred enhanced resistance against P. myriotylum compared to the overexpression of VrPR1-3 or VrPR1-4. Further functional analysis using the Nicotiana benthamiana transient overexpression system indicated that the resistance conferred by PR1 depends on the C-terminal CAPE1 domain of VrPR1-6 protein. Furthermore, a comparative transcriptome analysis of hairy roots overexpressing VrPR1-6 and GFP showed that "plant-pathogen interaction" pathway genes, including 10 genes related to the Ca²⁺ signaling pathway, were upregulated.

Conclusions

This study revealed that overexpression of VrPR1-3, VrPR1-4 and VrPR1-6 enhanced the resistance of V. radiata to P. myriotylum. Among them, the resistance of VrPR1-6 depends on the C-terminal CAPE1 domain and may involve Ca2 + -mediated signaling. These findings establish a foundation for further research into the immune defense pathways of V. radiata against P. myriotylum.