猪苓菌核不同发育时期转录组学差异表达研究

A landscape of transcriptome analysis of three sclerotia growth stages in Polyporus umbellatus

药用真菌猪苓菌核的发育代谢过程一直备受关注。为了解猪苓菌核的发育历程,该研究对3个不同时期的猪苓菌核进行了转录组学分析,共得到88. 12 Gb测序数据,包含85 235条unigene。对差异基因进行深度挖掘,筛选了有关跨膜运输、防御、极性生长、形态发育、黑色素合成、细胞壁合成、药效成分麦角甾醇和猪苓多糖合成功能的DEGs,从而推测了菌核发育的分子机制。根据DEGs的通路富集注释结果和相关报道,进一步推测猪苓菌核的发育是由于非生物胁迫(温差和缺氧)和生物胁迫(共生菌蜜环菌和伴生菌的入侵)诱导所致,造成菌核的氧化应激状态,加速合成膜转运蛋白和麦角甾醇从而实现物质的跨膜运输和转换,并通过WD40蛋白实现自身的防御机制。小GTPase和细胞色素P450响应环境信号,进而调控细胞的极性生长和形态发生,期间表皮黑色素沉积,细胞壁加厚,猪苓多糖合成,最终使得猪苓菌核的发育成熟。猪苓菌核不同时期转录组的研究为今后解析其发育历程和相关代谢过程的分子机制奠定了坚实的基础。

Polyporus umbellatus,a traditional Chinese precious medicine as long been used for eliminating dampness,diuresis and have effect on cancer,getting more and more popularly in China recently. And the developmental metabolic process of the medicinal fungus,P. umbellatus,has been gotten more attention. This study is for the first time to explore the three sclerotial growth stages in P. umbellatus,named " white Polyporus"( initial phase), " grey Polyporus"( developmental phase) and " black Polyporus"( mature phase),by utilizing the de novo transcriptome assembly analysis technology. Finally,we obtained 88. 12 Gb sequence containing85 235 unigenes( ≥200 bp) assembled and 100% were annotated. We identified genes differentially expressed among the three stages of the sclerotia and screened out MFSgst,ERG4/ERG24,WD40,Rho A,CYP450,PKS,GSase and CHS1,which may contribute to the production of medicinal secondary metabolites and the defense mechanism against the environmental stress and biological invasion. We did the qRT-PCR trial to verify our results,which is in line with expectations. Our results are purposed to unearth the molecular mechanism of the accumulation of active constituents in different stages of Polyporus sclerotia which can be applied in the production and protection of Polyporus effectively.