Soanes Darren M, Kershaw Michael J, Cooley R Neil, Talbot Nicholas J
School of Biological Sciences, University of Exeter, Washington Singer Laboratories, Perry Road, Exeter, EX4 4QG, UK.
Mol Plant Microbe Interact. 2002 Dec;15(12):1253-67. doi: 10.1094/MPMI.2002.15.12.1253.
The hydrophobin-encoding gene MPG1 of the rice blast fungus Magnaporthe grisea is highly expressed during the initial stages of host plant infection and targeted deletion of the gene results in a mutant strain that is reduced in virulence, conidiation, and appressorium formation. The green fluorescent protein-encoding allele sGFP was used as a reporter to investigate regulatory genes that control MPG1 expression. The MAP kinase-encoding gene PMK1 and the wide domain regulators of nitrogen source utilization, NPR1 and NUT1, were required for full expression of MPG1 in response to starvation stress. The CPKA gene, encoding the catalytic subunit of protein kinase A, was required for repression of MPG1 during growth in rich nutrient conditions. During appressorium morphogenesis, high-level MPG1 expression was found to require the CPKA and NPR1 genes. Expression of a destabilized GFP allele indicated that de novo MPG1 expression occurs during appressorium formation. Three regions of the MPG1 promoter were identified which are required for high-level expression of MPG1 during appressorium formation and are necessary for the biological activity of the MPG1 hydrophobin during spore formation and plant infection.
稻瘟病菌Magnaporthe grisea的疏水蛋白编码基因MPG1在寄主植物感染的初始阶段高度表达，该基因的靶向缺失导致一个突变菌株，其毒力、分生孢子形成和附着胞形成均有所降低。编码绿色荧光蛋白的等位基因sGFP被用作报告基因，以研究控制MPG1表达的调控基因。编码MAP激酶的基因PMK1以及氮源利用的广泛结构域调节因子NPR1和NUT1是MPG1在饥饿胁迫下完全表达所必需的。编码蛋白激酶A催化亚基的CPKA基因是在丰富营养条件下生长期间抑制MPG1所必需的。在附着胞形态发生过程中，发现高水平的MPG1表达需要CPKA和NPR1基因。不稳定的GFP等位基因的表达表明，MPG1的从头表达发生在附着胞形成过程中。鉴定出MPG1启动子的三个区域，它们是附着胞形成期间MPG1高水平表达所必需的，并且是MPG1疏水蛋白在孢子形成和植物感染期间生物活性所必需的。
