诱捕线虫(NT)真菌可以形成独特的感染结构(陷阱)来捕获和杀死自由生活的线虫,因此,可以在线虫的生物防治中发挥潜在的作用。节肢动物寡孢子菌是NT真菌的代表种。这里,我们对转录组进行了时程转录组测序(RNA-seq)分析,以了解在陷阱形成和捕食过程中寡孢菌的整体基因表达水平.我们确定了5,752个独特的差异表达基因,其中rac基因显著上调。选择性剪接事件发生在2,012个基因中,包括rac和rho2基因.此外,我们表征了三个RhoGTPases(Rho2,Rac,和Cdc42)在寡孢菌中使用基因破坏和多表型分析。我们的分析表明,AoRac和AoCdc42在菌丝体生长中起重要作用,脂质积累,DNA损伤,孢子形成,陷阱形成,致病性,以及寡孢子囊中的应激反应。AoCdc42和AoRac特别与Nox复合物的成分相互作用,从而调节活性氧的产生。此外,与蛋白激酶A相关的几个基因的转录水平,丝裂原活化蛋白激酶,突变体中p21激活的激酶也发生了改变,这表明RhoGTP酶可能在这些激酶的上游起作用。本研究强调了RhoGTPases在寡孢菌中的重要作用,并提供了信号通路在NT真菌陷阱形态发生和生活方式转变中的调控机制的见解。重要性诱捕线虫(NT)真菌广泛分布于陆地和水生生态系统中。它们广泛的适应性和灵活的生活方式使其成为控制病原线虫的理想药物。Arthrobotrys寡孢子是用于理解真菌和线虫之间相互作用的模型物种。这里,我们揭示了可变剪接事件在A.寡孢子囊的陷阱发展和生活方式转变中起着至关重要的作用。此外,RhoGTPases对生长产生不同的影响,发展,以及寡孢菌的致病性。特别是,AoRac是孢子形成和陷阱形态发生所必需的。此外,我们的分析表明,RhoGTP酶调节活性氧的产生,并在几种激酶的上游起作用。总的来说,这些结果扩大了我们的基因表达和选择性剪接事件的理解,从而为探索其在病原线虫生物防治中的潜在应用提供了基础。
Nematode-trapping (NT) fungi can form unique infection structures (traps) to capture and kill free-living nematodes and, thus, can play a potential role in the biocontrol of nematodes. Arthrobotrys oligospora is a representative species of NT fungi. Here, we performed a time course transcriptome sequencing (RNA-seq) analysis of transcriptomes to understand the global gene expression levels of A. oligospora during trap formation and predation. We identified 5,752 unique differentially expressed genes, among which the rac gene was significantly upregulated. Alternative splicing events occurred in 2,012 genes, including the rac and rho2 gene. Furthermore, we characterized three Rho GTPases (Rho2, Rac, and Cdc42) in A. oligospora using gene disruption and multiphenotypic analysis. Our analyses showed that AoRac and AoCdc42 play an important role in mycelium growth, lipid accumulation, DNA damage, sporulation, trap formation, pathogenicity, and stress response in A. oligospora. AoCdc42 and AoRac specifically interacted with components of the Nox complex, thus regulating the production of reactive oxygen species. Moreover, the transcript levels of several genes associated with protein kinase A, mitogen-activated protein kinase, and p21-activated kinase were also altered in the mutants, suggesting that Rho GTPases might function upstream from these kinases. This study highlights the important role of Rho GTPases in A. oligospora and provides insights into the regulatory mechanisms of signaling pathways in the trap morphogenesis and lifestyle transition of NT fungi. IMPORTANCE Nematode-trapping (NT) fungi are widely distributed in terrestrial and aquatic ecosystems. Their broad adaptability and flexible lifestyles make them ideal agents for controlling pathogenic nematodes. Arthrobotrys oligospora is a model species employed for understanding the interaction between fungi and nematodes. Here, we revealed that alternative splicing events play a crucial role in the trap development and lifestyle transition in A. oligospora. Furthermore, Rho GTPases exert differential effects on the growth, development, and pathogenicity of A. oligospora. In particular, AoRac is required for sporulation and trap morphogenesis. In addition, our analysis showed that Rho GTPases regulate the production of reactive oxygen species and function upstream from several kinases. Collectively, these results expand our understanding of gene expression and alternative splicing events in A. oligospora and the important roles of Rho GTPases in NT fungi, thereby providing a foundation for exploring their potential application in the biocontrol of pathogenic nematodes.