PDF(Pubmed)
Abstract：
Asexual development is the main propagation and transmission mode of Beauveria bassiana and the basis of its pathogenicity. The regulation mechanism of conidiation and the key gene resources for utilization are key links to improving the conidia yield and quality of Beauveria bassiana. Their clarification may promote the industrialization of fungal pesticides. Here, we compared the regulation of morphology, resistance to external stress, virulence, and nutrient utilization capacity between the upstream developmental regulatory gene fluG and the key genes brlA, abaA, and wetA in the central growth and development pathway. The results showed that the ΔbrlA and ΔabaA mutants completely lost the capacity to conidiate and that the ΔwetA mutant had seriously reduced conidiation capacity. Although the deletion of fluG did not reduce the conidiation ability as much as deletions of brlA, abaA, and wetA, it significantly reduced the fungal response to external stress, virulence, and nutrient utilization, while the deletion of the three other genes had little effect. Via transcriptome analysis and screening the yeast nuclear system library, we found that the differentially expressed genes in the ΔfluG mutants were concentrated in the signaling pathways of ABC transporters, propionate metabolism, tryptophan metabolism, DNA replication, mismatch repair, and fatty acid metabolism. FluG directly acted on 40 proteins that were involved in various signaling pathways such as metabolism, oxidative stress, and cell homeostasis. The analysis indicated that the regulatory function of fluG was mainly involved in DNA replication, cell homeostasis, fungal growth and metabolism, and the response to external stress. Our results revealed the biological function of fluG in asexual development and the responses to several environmental stresses as well as its influence on the asexual development regulatory network in B. bassiana.
摘要：
无性发育是球孢白僵菌的主要繁殖和传播方式,是其致病的基础。分生孢子的调控机制和关键基因资源的利用是提高球孢白僵菌分生孢子产量和品质的关键环节。它们的澄清可能会促进真菌农药的产业化。这里,我们比较了形态学的调节，抵抗外部压力，毒力,上游发育调控基因fluG和关键基因brlA之间的营养利用能力，abaA,和wetA在中央生长发育途径中。结果表明，ΔbrlA和ΔabaA突变体完全失去了分生孢子的能力，而ΔwetA突变体的分生孢子能力严重降低。尽管fluG的缺失并没有像brlA的缺失那样降低分生孢子的能力，abaA,和wetA,它显著降低了真菌对外部压力的反应，毒力,和养分利用，而其他三个基因的缺失影响不大。通过转录组分析和酵母核系统文库的筛选,我们发现ΔfluG突变体的差异表达基因集中在ABC转运体的信号通路中，丙酸代谢，色氨酸代谢,DNA复制,失配修复,和脂肪酸代谢。FluG直接作用于参与各种信号通路如代谢的40种蛋白质,氧化应激，和细胞稳态。分析表明，fluG的调控功能主要参与DNA复制，细胞稳态，真菌生长和代谢，以及对外部压力的反应。我们的研究结果揭示了fluG在无性发育中的生物学功能，对几种环境压力的响应以及对白杨无性发育调控网络的影响。
