Cowpea lipid transfer protein 1 regulates plant defense by inhibiting the cysteine protease of cowpea mosaic virus
Year: 2024
Type: article
Abstract: Many virus genomes encode proteases that facilitate infection. The molecular mechanism of plant recognition of viral proteases is largely unexplored. Using the system of Vigna unguiculata and cowpea mosaic virus (CPMV), we identified a cowpea lipid transfer protein (LTP1) which interacts with CPMV-encoded 24KPro, a cysteine protease, but not with the enzymatically inactive mutant 24KPro(C166A). Biochemical assays showed that LTP1 inhibited 24KPro proteolytic cleavage of the coat protein precursor large coat protein-small coat protein. Transient overexpression of LTP1 in cowpea reduced CPMV infection, whereas RNA interference-mediated LTP1 silencing increased CPMV accumulation in cowpea. LTP1 is mainly localized in the apoplast of uninfected plant cells, and after CPMV infection, most of the LTP1 is relocated to intracellular compartments, including chloroplast. Moreover, in stable LTP1 -transgenic Nicotiana benthamiana plants, LTP1 repressed soybean mosaic virus (SMV) nuclear inclusion a protease activity, and accumulation of SMV was significantly reduced. We propose that cowpea LTP1 suppresses CPMV and SMV accumulation by directly inhibiting viral cysteine protease activity.
Authors: Jie Ji, Shengli Du, Kun Wang, Ziyan Qi, Chunyang Zhang, Rui Wang, George Bruening, Pengwei Wang, Deqiang Duanmu, Qiuling Fan
Language: English
Topic: Plant Virus Research Studies
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: hybrid
Funders: National Natural Science Foundation of China, China Agricultural University, Sun Yat-sen University, Ministry of Science and Technology of the People's Republic of China, Hubei University of Technology, Inner Mongolia University, Huazhong Agricultural University, Nanjing Agricultural University, Hubei University
Awards: G6253185825, G6548180406
OpenAlex ID: W4401688249