Functional and structural comparison of pyrrolnitrin- and iprodione-induced modifications in the class III histidine-kinase Bos1 of Botrytis cinerea.
Functional and structural comparison of pyrrolnitrin- and iprodione-induced modifications in the class III histidine-kinase Bos1 of Botrytis cinerea.
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DOI：
10.1371/journal.pone.0042520
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Bardin M
中科院分区：
文献类型：
--
作者：
Fillinger S;Ajouz S;Nicot PC;Leroux P;Bardin M
二甲酰亚胺和苯基吡咯是常用来对抗植物病原子囊菌的杀菌剂。尽管许多研究已证明它们对真菌渗透传感系统的影响，但其作用模式仍不清楚。对任一或两种杀菌剂类别具有抗性的实验室或现场突变体通常在渗透信号转导级联的传感器组氨酸激酶中存在点突变。在本研究中，我们比较了灰霉病菌对二甲酰亚胺异菌脲和吡咯尼群（苯基吡咯杀菌剂的结构类似物）的抗性机制。吡咯尼群诱导的突变体和异菌脲诱导的灰霉病突变体是在体外产生的。对于吡咯尼群诱导的突变体，对吡咯尼群的高水平抗性与对异菌脲的高水平抗性相关。对于异菌脲诱导的突变体，对异菌脲的高水平抗性产生了对吡咯尼群和苯基吡咯的不同水平的抗性。所有选定的突变体都表现出对高渗透压的超敏性，并且无论它们对苯基吡咯的抗性水平如何，与亲本表型相比，它们都表现出强烈降低的适应性参数（孢子形成、菌丝体生长、对植物的攻击性）。大多数突变体在渗透传感 III 类组氨酸激酶中呈现出影响 HAMP 结构域的修饰。应用 bos1 基因的定点诱变来验证八个已识别的突变。 HAMP 结构域的结构建模表明，HAMP 结构域内疏水残基的替换通常会影响其螺旋结构，可能会消除信号转导。将突变表型与 HAMP 结构进行比较，我们的研究表明，扰乱 HAMP2-4 螺旋结构的突变会废除信号转导，导致功能丧失表型。残基 E529、M427 和 T581 的突变不影响 HAMP 结构，突显了它们参与信号转导。 E529 和 M427 似乎主要参与渗透信号转导。
Dicarboximides and phenylpyrroles are commonly used fungicides against plant pathogenic ascomycetes. Although their effect on fungal osmosensing systems has been shown in many studies, their modes-of-action still remain unclear. Laboratory- or field-mutants of fungi resistant to either or both fungicide categories generally harbour point mutations in the sensor histidine kinase of the osmotic signal transduction cascade. In the present study we compared the mechanisms of resistance to the dicarboximide iprodione and to pyrrolnitrin, a structural analogue of phenylpyrrole fungicides, in Botrytis cinerea. Pyrrolnitrin-induced mutants and iprodione-induced mutants of B. cinerea were produced in vitro. For the pyrrolnitrin-induced mutants, a high level of resistance to pyrrolnitrin was associated with a high level of resistance to iprodione. For the iprodione-induced mutants, the high level of resistance to iprodione generated variable levels of resistance to pyrrolnitrin and phenylpyrroles. All selected mutants showed hypersensitivity to high osmolarity and regardless of their resistance levels to phenylpyrroles, they showed strongly reduced fitness parameters (sporulation, mycelial growth, aggressiveness on plants) compared to the parental phenotypes. Most of the mutants presented modifications in the osmosensing class III histidine kinase affecting the HAMP domains. Site directed mutagenesis of the bos1 gene was applied to validate eight of the identified mutations. Structure modelling of the HAMP domains revealed that the replacements of hydrophobic residues within the HAMP domains generally affected their helical structure, probably abolishing signal transduction. Comparing mutant phenotypes to the HAMP structures, our study suggests that mutations perturbing helical structures of HAMP2-4 abolish signal-transduction leading to loss-of-function phenotype. The mutation of residues E529, M427, and T581, without consequences on HAMP structure, highlighted their involvement in signal transduction. E529 and M427 seem to be principally involved in osmotic signal transduction.
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影响因子：
1.8
作者：
Alberoni, Giulia;Collina, Marina;Brunelli, Agostino
通讯作者：
Brunelli, Agostino
影响因子：
2.1
作者：
Aravind, L;Ponting, CP
通讯作者：
Ponting, CP
影响因子：
2.6
作者：
Chernin, L;Brandis, A;Chet, I
通讯作者：
Chet, I
影响因子：
2.5
作者：
Avenot, H;Simoneau, P;Bataillé-Simoneau, N
通讯作者：
Bataillé-Simoneau, N
DOI：
10.1093/bioinformatics/btq662
发表时间：
2011-02-01
期刊：
Bioinformatics (Oxford, England)
影响因子：
--
作者：
Benkert P;Biasini M;Schwede T
通讯作者：
Schwede T