The secondary metabolite regulator,BbSmr1, is a central regulator of conidiation via theBrlA-AbaA-WetApathway inBeauveria bassiana
The secondary metabolite regulator,BbSmr1, is a central regulator of conidiation via theBrlA-AbaA-WetApathway inBeauveria bassiana
复制标题
次级代谢调节因子 BbSmr1 是白僵菌中通过 BrlA-AbaA-WetA 途径形成分生孢子的中心调节因子
DOI：
10.1111/1462-2920.15155
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发表时间：
2020-08-23
影响因子：
5.1
通讯作者：
Fan, Yan-Hua
中科院分区：
文献类型：
--
作者：
Chen, Jin-Feng;Liu, Yu;Fan, Yan-Hua
球孢白僵菌是一种昆虫真菌病原菌，广泛应用于害虫生物防治。气生分生孢子是一种侵染性繁殖体，其产量和活力对该真菌的田间应用有很大影响，但对触发分生孢子发生的分子调控机制知之甚少。在本研究中，我们发现次生代谢物调节因子BbSmr1参与了无性分生孢子发育和胁迫反应的调节。球孢菌。Bbsmr1基因缺失导致在固体培养基上出现明显的绒毛状表型，降低了分生孢子产量，加速了分生孢子萌发，提高了对H(2)O(2)胁迫和细胞壁抑制剂的耐受性。Bbsmr1基因的缺失还会导致分生孢子细胞壁增厚和细胞表位改变。在Bbsmr1菌株中过表达Bbbr1A或BBabaA都能挽救分生孢子发育和胁迫反应的表型。BbSmr1通过直接与BbbrlA启动子的A4GA3序列结合来激活BbbrlA转录。BbBrlA进而与Bbsmr1的启动子结合，负向调节Bbsmr1的表达。这些结果表明，BbSmr1正向调节分生孢子的发育。Bassiana通过激活中心发育途径BrlA-ABAA-Weta，为昆虫病原真菌的发育调控机制提供了见解。
The filamentous fungusBeauveria bassiana, an insect fungal pathogen, is widely used for pest biocontrol. Aerial conidia are infectious propagules, and their yield and viability greatly affect the field application of this fungus; however, little is known about the molecular regulatory mechanism of the triggered conidiation. In the present study, we find that the secondary metabolite regulator BbSmr1 is involved in the regulation of asexual conidiation development and stress response inB. bassiana. A deficiency inBbsmr1results in a prominent fluffy-like phenotype on solid medium, decreased conidial yield, accelerated conidial germination, as well as increased tolerance to H(2)O(2)stress and cell wall inhibitors. The deletion ofBbsmr1also leads to thickened conidial cell walls and changed cell epitopes. Overexpressing eitherBbbrlAorBbabaAin the increment Bbsmr1strain can rescue the phenotypes of conidial development and stress response. BbSmr1 activatesBbbrlAtranscription by directly binding to the A4GA3 sequence of theBbbrlApromoter. BbBrlA in turn binds to the promoter ofBbsmr1and negatively regulates the expression ofBbsmr1. These results indicate that BbSmr1 positively regulates conidial development inB. bassianaby activating the central development pathway BrlA-AbaA-WetA and provides insights into the developmental regulatory mechanism of entomopathogenic fungi.