Miro GTPase controls mitochondrial behavior affecting stress tolerance and virulence of a fungal insect pathogen
Miro GTPase controls mitochondrial behavior affecting stress tolerance and virulence of a fungal insect pathogen
复制标题
Miro GTPase 控制线粒体行为，影响真菌昆虫病原体的胁迫耐受性和毒力
DOI：
10.1016/j.fgb.2016.05.005
复制
发表时间：
2016-08-01
影响因子：
3
通讯作者：
Feng, Ming-Guang
中科院分区：
文献类型：
--
作者：
Guan, Yi;Wang, Ding-Yi;Feng, Ming-Guang
Miro同源物是一种小的线粒体Rho GTP酶，属于生物体中的Ras超家族，通常在丝状真菌中未被发现。在这里，我们在球孢白僵菌中鉴定出一种米罗同源物(BMiro)，这是一种丝状真菌昆虫病原体，是一种经典的害虫生防剂。这个同源物被证明以一种完全依赖于短的C端跨膜结构域的方式锚定在线粒体外膜上。由于bmiro缺失，菌丝细胞内线粒体大量聚集，质量和流动性降低，同时伴随着ATP含量的显著下降，但线粒体形态变化不大。在微量培养条件下，缺失突变体对钙、锰、锌和镁的耐受性分别比野生型高42%、37%、19%和10%。缺失突变体在分生孢子萌发、营养生长、耐热性、抗UV-B和致病力方面也表现出轻微的缺陷，尽管对氧化和渗透胁迫没有反应。所有这些表型变化都通过靶向基因互补得到修复。我们的结果表明，bMiro可以控制线粒体的分布和运动，这是运输ATP形式的能量和金属离子所必需的，并通过这种控制对真菌抗害虫的潜力做出了重要贡献。(C)2016 Elsevier Inc.保留所有权利。
Miro homologues are small mitochondrial Rho GTPases belonging to the Ras superfamily across organisms and are generally unexplored in filamentous fungi. Here we identified a Miro orthologue (bMiro) in Beauveria bassiana, a filamentous fungal insect pathogen as a classic biological control agent of insect pests. This orthologue was proven to anchor on mitochondrial outer membrane in a manner depending completely upon a short C-terminal transmembrane domain. As a result of bmiro deletion, mitochondria in hyphal cells were largely aggregated, and their mass and mobility were reduced, accompanied with a remarkable decrease in ATP content but little change in mitochondrial morphology. The deletion mutant became 42%, 37%, 19% and 10% more tolerant to Ca2+, Mn2+, Zn2+ and Mg2+ than wild-type, respectively, during cultivation in a minimal medium under normal conditions. The deletion mutant also showed mild defects in conidial germination, vegetative growth, thermotolerance, UV-B resistance and virulence despite null response to oxidative and osmotic stresses. All these phenotypic changes were restored by targeted gene complementation. Our results indicate that bMiro can control mitochondrial distribution and movement required for the transport of ATP-form energy and metal ions and contributes significantly to the fungal potential against insect pests through the control. (C) 2016 Elsevier Inc. All rights reserved.