We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Involvement of putative response regulator genes of the rice blast fungus Magnaporthe oryzae in osmotic stress response, fungicide action, and pathogenicity.
- Authors
Motoyama, Takayuki; Ochiai, Naoko; Morita, Masumi; Iida, Yuki; Usami, Ron; Kudo, Toshiaki
- Abstract
Rice blast fungus ( Magnaporthe oryzae) has ten histidine kinases (HKs), one histidine-containing phosphotransfer protein (HPt), and three response regulators (RRs) as putative components of the two-component signal transduction system (TCS). Here, we constructed knockout mutants of two putative RR genes ( MoSSK1, MoSKN7) and a RR homolog gene ( MoRIM15) to analyze the roles of TCS in environmental adaptation and pathogenicity. The Δ Mossk1 strain had increased sensitivity to high osmolarity and decreased sensitivity to fludioxonil. The Δ Moskn7 strain had slightly decreased sensitivity to fludioxonil. The involvement of MoSkn7 in the osmoresponse was obvious only on the Δ Mossk1 background. These results show that MoSsk1 and MoSkn7 are major and minor contributors, respectively, in the high osmolarity response and fludioxonil action. The Δ Mossk1 strain was more osmosensitive than the predicted upstream HK gene disruptant Δ hik1, which shows sugar-specific high osmolarity sensitivity. The Δ Mossk1 and Δ Moskn7 strains showed enhanced hyphal melanization, suggesting that RRs regulate hyphal melanization. MoSsk1 and MoRim15 are required for full virulence, because the Δ Mossk1 and Δ Morim15 strains exhibited reduced virulence. These results suggest that the putative RRs of the rice blast fungus are involved in the osmotic stress response, fludioxonil action, and pathogenicity.
- Subjects
FUNGI; GENES; CELLULAR signal transduction; FUNGICIDES; OXIDATIVE stress; MICROBIAL virulence
- Publication
Current Genetics, 2008, Vol 54, Issue 4, p185
- ISSN
0172-8083
- Publication type
Article
- DOI
10.1007/s00294-008-0211-0