Gene Profiling in Late Blight Resistance in Potato Genotype SD20.

Xiaohui Yang,Xiao Guo,Pei Ye,Xingyao Xiong,Yu Yang,Daofeng Dong,Guangcun Li,Jun Liu

doi:10.3390/ijms19061728

Abstract

Late blight caused by the oomycete fungus Phytophthora infestans (Pi) is the most serious obstacle to potato (Solanum tuberosum) production in the world. A super race isolate, CN152, which was identified from Sichuan Province, China, could overcome nearly all known late blight resistance genes and caused serious damage in China. The potato genotype SD20 was verified to be highly resistant to CN152; however, the molecular regulation network underlying late blight resistance pathway remains unclear in SD20. Here, we performed a time-course experiment to systematically profile the late blight resistance response genes using RNA-sequencing in SD20. We identified 3354 differentially expressed genes (DEGs), which mainly encoded transcription factors and protein kinases, and also included four NBS-LRR genes. The late blight responsive genes showed time-point-specific induction/repression. Multi-signaling pathways of salicylic acid, jasmonic acid, and ethylene signaling pathways involved in resistance and defense against Pi in SD20. Gene Ontology and KEGG analyses indicated that the DEGs were significantly enriched in metabolic process, protein serine/threonine kinase activity, and biosynthesis of secondary metabolites. Forty-three DEGs were involved in immune response, of which 19 were enriched in hypersensitive response reaction, which could play an important role in broad-spectrum resistance to Pi infection. Experimental verification confirmed the induced expression of the responsive genes in the late blight resistance signaling pathway, such as WRKY, ERF, MAPK, and NBS-LRR family genes. Our results provided valuable information for understanding late blight resistance mechanism of potato.

Highlights

The potato (Solanum tuberosum L.) is the third most important food crop in the world after wheat and rice, with an annual global production exceeding 374 million tons [1]
Potato production is highly affected by late blight, a disease caused by the oomycete Phytophthora infestans (Pi), which has become a serious obstacle to the development of the potato industry in China and around the world
To gain a comprehensive knowledge of the transcriptional response of S. tuberusom to Pi infection, we conducted a transcriptome profiling analysis of SD20 that was inoculated with the Pi super race isolate CN152 for 0, 24, 48, and 72 h post infection as well as H2O as the mock treatment (Figure 2A)

Summary

Introduction

The potato (Solanum tuberosum L.) is the third most important food crop in the world after wheat and rice, with an annual global production exceeding 374 million tons [1]. Potato production is highly affected by late blight, a disease caused by the oomycete Phytophthora infestans (Pi), which has become a serious obstacle to the development of the potato industry in China and around the world. Potato late blight caused the great famine of 1845–1852 in Ireland. During this famine around one million people died of hunger and one million more emigrated out of Ireland. Control of this disease is both expensive and time-consuming. The cost of control and damage by this disease is estimated at billions of U.S dollars per year [2]

Methods

Results

Conclusion