Transcriptome and proteome analyses reveal the regulatory networks and metabolite biosynthesis pathways during the development of Tolypocladium guangdongense

Abstract

Tolypocladium guangdongense has a similar metabolite profile to Ophiocordyceps sinensis, a highly regarded fungus used for traditional Chinese medicine with high nutritional and medicinal value. Although the genome sequence of T. guangdongense has been reported, relatively little is known about the regulatory networks for fruiting body development and about the metabolite biosynthesis pathways. In order to address this, an analysis of transcriptome and proteome at differential developmental stages of T. guangdongense was performed. In total, 9076 genes were found to be expressed and 2040 proteins were identified. There were a large number of genes that were significantly differentially expressed between the mycelial stage and the stages. Interestingly, the correlation between the transcriptomic and proteomic data was low, suggesting the importance of the post-transcriptional processes in the growth and development of T. guangdongense. Among the genes/proteins that were both differentially expressed during the developmental process, there were numerous heat shock proteins and transcription factors. In addition, there were numerous proteins involved in terpenoid, ergosterol, adenosine and polysaccharide biosynthesis that also showed significant downregulation in their expression levels during the developmental process. Furthermore, both tryptophan and tryptamine were present at higher levels in the primordium stage. However, indole-3-acetic acid (IAA) levels continuously decreased as development proceeded, and the enzymes involved in IAA biosynthesis were also clearly differentially downregulated. These data could be meaningful in studying the molecular mechanisms of fungal development, and for the industrial and medicinal application of macro-fungi.