AoChk1 Is Required for Sporulation, Trap Formation, and Metabolic Process in Arthrobotrys oligospora.

Chk1, a highly conserved serine/threonine protein kinase, functions as a critical regulator of fungal cell cycle progression, mitotic fidelity, and DNA damage response. In this study, we characterized an orthologous Chk1 (AoChk1) in a ubiquitous nematode-trapping fungus, Arthrobotrys oligospora, through targeted gene knockout coupled with integrated phenotypic, metabolomic, and transcriptomic analyses. This study aims to elucidate the function and potential regulatory networks of AoChk1 in A. oligospora. Deletion of Aochk1 leads to significant reductions in nucleus number, hyphal cell length, conidial production, and trap formation, but an increase in the accumulation of lipid droplets and autophagy. In addition, transcriptomics data indicate that AoChk1 plays an important role in cell cycle and division, nuclear architecture and organelle dynamics, protein homeostasis maintenance, and membrane systems. In addition, the inactivation of the Aochk1 exhibited remarkably reduced metabolite abundance relative to the WT strain. In conclusion, our results identify AoChk1 as an important regulator of asexual development, pathogenicity, and metabolic processes in A. oligospora.