State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, China.
School of Resource, Environment and Chemistry, Chuxiong Normal University, Chuxiong, 675000, China.
Sci China Life Sci. 2022 Dec;65(12):2455-2471. doi: 10.1007/s11427-022-2118-0. Epub 2022 Jul 8.
Predatory fungi possess intricate signal transduction systems that regulate their development and support successful infection of the host. Herein, we characterized three components of the cell wall integrity-controlling pathway, namely protein kinase C (AoPKC), SLT2-MAPK (AoSLT2), and SWI6 (AoSWI6), in a representative nematode-trapping fungus Arthrobotrys oligospora, using gene disruption and multi-omics approaches. The phenotypic traits (such as mycelia development, conidiation, stress response, and trap morphogenesis) and metabolic profiles of ΔAopkc and ΔAoswi6 mutants were similar but differed from those of the ΔAoslt2 mutants. Transcriptomic analysis indicated that the genes differentially expressed in the absence of Aoswi6 were involved in DNA replication, repair, and recombination during trap formation. Moreover, the yeast two-hybrid assay showed that AoPKC interacted with AoSWI6, suggesting that in A. oligospora, PKC can directly regulate SWI6, bypassing the SLT2 signaling cascade. Conclusively, our findings deepen our understanding of the regulatory mechanism of asexual development and lifestyle switching in nematode-trapping fungi.
捕食性真菌具有复杂的信号转导系统，调节其发育并支持对宿主的成功感染。在此，我们使用基因敲除和多组学方法，对代表性的线虫诱捕真菌节丛孢（Arthrobotrys oligospora）中的三个细胞壁完整性控制途径的组成部分，即蛋白激酶 C（AoPKC）、SLT2-MAPK（AoSLT2）和 SWI6（AoSWI6）进行了表征。ΔAopkc 和 ΔAoswi6 突变体的表型特征（如菌丝体发育、分生孢子形成、应激反应和诱捕形态发生）和代谢谱与ΔAoslt2 突变体相似，但不同。转录组分析表明，在缺乏 AoSWI6 的情况下差异表达的基因参与了诱捕形成过程中的 DNA 复制、修复和重组。此外，酵母双杂交试验表明 AoPKC 与 AoSWI6 相互作用，表明在节丛孢中，PKC 可以直接调节 SWI6，绕过 SLT2 信号级联。总之，我们的研究结果加深了我们对线虫诱捕真菌无性发育和生活方式转变的调控机制的理解。
