R-SNARE homolog MoSec22 is required for conidiogenesis, cell wall integrity, and pathogenesis of Magnaporthe oryzae.
Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins mediate intracellular vesicle fusion, which is an essential cellular process of the eukaryotic cells. To investigate the role of SNARE proteins in the rice blast fungus Magnaporthe oryzae, MoSec22, an ortholog of Saccharomyces cerevisiae SNARE protein Sec22, was identified and the MoSEC22 gene disrupted. MoSec22 restored a S. cerevisiae sec22 mutant in resistance to cell wall perturbing agents, and the ΔMosec22 mutant also exhibited defects in mycelial growth, conidial production, and infection of the host plant. Treatment with oxidative stress inducers indicated a breach in cell wall integrity, and staining and quantification assays suggested abnormal chitin deposition on the lateral walls of hyphae of the ΔMosec22 mutant. Furthermore, hypersensitivity to the oxidative stress correlates with the reduced expression of the extracellular enzymes peroxidases and laccases. Our study thus provides new evidence on the conserved function of Sec22 among fungal organisms and indicates that MoSec22 has a role in maintaining cell wall integrity affecting the growth, morphogenesis, and virulence of M. oryzae.
Song
Wenwen
W
Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, Nanjing, China.
Dou
Xianying
X
Qi
Zhongqiang
Z
Wang
Qi
Q
Zhang
Xing
X
Zhang
Haifeng
H
Guo
Min
M
Dong
Suomeng
S
Zhang
Zhengguang
Z
Wang
Ping
P
Zheng
Xiaobo
X
D002473:Cell Wall; D042845:Laccase / Q000378:metabolism; D020082:Magnaporthe / Q000472:pathogenicity*; D012275:Oryza / Q000378:metabolism / Q000382:microbiology*; D018384:Oxidative Stress; D010802:Phylogeny; D050683:R-SNARE Proteins / Q000145:classification / Q000502:physiology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014774:Virulence
D050683:R-SNARE Proteins; D017382:Reactive Oxygen Species; D042845:Laccase