MPG1, a gene encoding a fungal hydrophobin of Magnaporthe grisea, is involved in surface recognition
MPG1, a gene encoding a fungal hydrophobin of Magnaporthe grisea, is involved in surface recognition
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DOI：
10.1094/mpmi-9-0450
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发表时间：
1996-08-01
影响因子：
3.5
通讯作者：
Ebbole, DJ
中科院分区：
文献类型：
--
作者：
Beckerman, JL;Ebbole, DJ
稻瘟病菌（Magnaporthe grisea）分生孢子萌发的芽管在接触到叶片表面时，形成一种称为附着胞的侵染结构，这种结构允许直接穿透植物细胞。MPG 1的缺失降低了附着胞形成的效率。我们发现酵母提取物在体外抑制MPG 1的表达并抑制水稻病原菌菌株Guy 11的附着胞发育。mpg 1突变体的附着胞形成通过与野生型细胞共接种而被反式拯救，MPG 1是响应于宿主表面或高度疏水的人工底物而有效诱导附着胞所必需的，然而，我们鉴定了几种可以支持mpg 1菌株的有效附着胞形成的人工底物，这一发现表明Mpg 1 p不是附着胞形成所特异需要的，此外，鉴定了形成附着胞的能力的时间窗口;形成附着胞的决定发生在分生孢子萌发后约6至8小时，在此关键时间之后，细胞不再能够响应诱导线索而形成附着胞。这些研究表明MPG 1疏水蛋白是宿主识别所必需的，并且它作为细胞分化的形态发生信号。
Upon encountering a leaf surface, emergent germ tubes from conidia of the rice blast fungus, Magnaporthe grisea, form infection structures called appressoria that allow direct penetration of plant cells, The MPG1 gene encodes a fungal hydrophobin of M. grisea that is expressed during development of aerial hyphae, conidia; and appressoria, Deletion of MPG1 reduces the efficiency of appressorium formation, We found that yeast extract repressed MPG1 expression in vitro and inhibited appressorium development of the rice pathogen, strain Guy11. Appressorium formation of mpg1 mutants is rescued in trans by coinoculation with wild-type cells, MPG1 is required for efficient induction of appressoria in response to a host surface or highly hydrophobic artificial substrates, However, we identified several artificial substrates that can support efficient appressorium formation of mpg1 strains, This finding suggests that Mpg1p is not specifically required for appressorium formation, but is involved in the interaction with, and recognition of, the host surface, Additionally, a time window of competence to form appressoria was identified; the decision to form appressoria occurs approximately 6 to 8 h following conidial germination, After this critical time, cells are no longer able to form appressoria in response to inductive cues. These studies indicate that MPG1 hydrophobin is required for host recognition and that it acts as a morphogenetic signal for cellular differentiation.