Study On Qde-2 In Trap Formation Of Arthrobotrys Oligospora Based On Comparative Transcriptome Analysis

RNAi(RNA interference)is an important mechanism underlying gene regulation.The RISC complex(RNA-induced silencing complex)plays a key role in RNAi,and the Argonaute protein is the core component of the executive function of the RISC complex.QDE-2,the Argonaute protein of Arthrobotrys oligospora,was previously reported to play an important role in trapping nematodes,and the disruption of qde-2 will lead to severe deficiency of A.oligospora to develop adhesive networks on induction.However,the underlying mechanism of qde-2 in trap formation is still unclear.In this study,we performed comparative transcriptome analysis of RNA-seq data at three key time-points of trap induction by nematode extracts from wild type and qde-2 deletion strain.We identified the potential genes with significant expression change between wild type strain and qde-2 deletion strain.Cluster analysis of these genes revealed eight functional modules.Among them,four genes(ao0300952,ao0305621,ao0306782,ao0308204)were greatly regulated by qde-2,and they might interfere with trap formation by affecting the expression of retrotransposons.Functional analysis including GO annotation,KEGG annotation,enrichment analysis,transcription factor analysis,CaZyme annotation and protein-protein interaction(PPI)network analysis of the differentially expressed genes between wild type and qde-2 deletion strain,showed that the deletion of qde-2 leads to changes in a variety of biological processes,including the expression of transcription factors,methylations;Gene expression analysis suggested trap formation might be related to cell oxidation and detoxification,ribosome synthesis,translation,peroxisome and transmembrane transport.In addition,the top 10 differentially expressed genes at the late stage also suggested that sporopyrone might be an important secondary metabolite to kill nematodes.In summary,comparative transcriptome analysis of wild type and qde-2 deletion strain in A.oligospora trap formation revealed the key potential genes regulated by QDE-2,providing new insights into the underlying mechanisms of trap induction of nematode-trapping fungi and the important roles of qde-2.The study may also provide basis for biological control of nematodes using nematode-trapping fungi.