BbSNF1 contributes to cell differentiation, extracellular acidification, and virulence in Beauveria bassiana, a filamentous entomopathogenic fungus
BbSNF1 contributes to cell differentiation, extracellular acidification, and virulence in Beauveria bassiana, a filamentous entomopathogenic fungus
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BbSNF1 有助于白僵菌（一种丝状昆虫病原真菌）的细胞分化、细胞外酸化和毒力
DOI：
10.1007/s00253-014-5907-0
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发表时间：
2014-10-01
影响因子：
5
通讯作者：
Ying, Sheng-Hua
中科院分区：
文献类型：
--
作者：
Wang, Xiu-Xiu;He, Pu-Hong;Ying, Sheng-Hua
SNF 1/AMPK蛋白激酶在真菌发育和代谢产物抑制基因的激活中起重要作用。在这项研究中，我们的特点球孢白僵菌SNF 1直系同源物的作用。Delta BbSNF 1突变体的营养生长在不同的碳/氮源上减少了16 - 50%。转录分析揭示了蛋白酶和几丁质酶的集合，当突变体生长在复杂的碳/氮源上时，不诱导。BbSNF 1也有助于细胞外酸化。Delta BbSNF 1突变体增强了乳酸、草酸和柠檬酸的生产，但草酸的生产被部分抑制。转录分析表明，一组参与酸的生物合成和分泌的基因被改变的破坏突变体，表明BbSNF 1控制不同的有机酸的生产与不同的机制。BbSNF 1的缺失导致突变体中分生孢子形成（57- 75%）和芽生孢子产量（80- 95%）的显著降低。此外，BbSNF 1调节芽生孢子形成结构的形态和体外芽生孢子的大小。昆虫生物测定显示，Delta BbSNF 1菌株在局部生物测定中表现出大约两倍的中位致死时间，但在血腔内测定中的毒力降低（类似于20%的变化）不如局部生物测定中那么大。这些数据表明，BbSNF 1是重要的渗透通过主机角质层。此外，BbSNF 1调控的一系列与芽生孢子形成相关的基因主要参与代谢、细胞周期和运输。总之，SNF 1/AMPK激酶有助于B的生防潜力。通过介导细胞分化和碳/氮源的利用，
SNF1/AMPK protein kinase plays important roles in fungal development and activation of catabolite-repressed genes. In this study, we characterized the role of the Beauveria bassiana SNF1 ortholog. The vegetative growth of the Delta BbSNF1 mutant was reduced by 16 to 50 % on diverse carbon/nitrogen sources. Transcriptional analysis revealed a collection of proteases and chitinases that were not induced when the mutant was grown on complex carbon/nitrogen sources. BbSNF1 also contributes to extracellular acidification. The Delta BbSNF1 mutant had enhanced production of lactic, pyruvic, and citric acid, but oxalic acid production was partially repressed. Transcriptional analysis showed that a set of genes involved in acid biosynthesis and secretion was changed in the disruption mutant, indicating that BbSNF1 controls the production of different organic acids with different mechanisms. Deletion of BbSNF1 resulted in a significant reduction in conidiation (57-75 %) and blastospore yield (80-95 %) in the mutant. Additionally, BbSNF1 regulates the morphology of blastospore-forming structures and the in vitro blastospore size. Insect bioassays revealed that the Delta BbSNF1 strain exhibited an approximately doubled median lethal time in topical bioassays, but the decreased virulence in intrahemocoel assays (similar to 20 % change) was not as great as in the topical bioassays. These data suggest that BbSNF1 is important in penetration through the host cuticle. Moreover, a series of genes regulated by BbSNF1 and associated with blastospore formation were primarily involved in metabolism, cell cycle, and transportation. In conclusion, the SNF1/AMPK kinase contributes to the biocontrol potential of B. bassiana by mediating cellular differentiation and utilization of carbon/nitrogen sources.