青藏高原野生冬虫夏草子实体发育时期的宏转录组研究  

Metatranscriptomics analysis of the fruiting caterpillar fungus collected from the Qinghai-Tibetan plateau

作　　者：张四维 岑凯 刘艳[1] 周选围[1] 王成树[2] ZHANG SiWei;CEN Kai;LIU Yan;ZHUO Xuan-Wei;WANG ChengShu(School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China;CAS Key Laboratory oflnsect Developmental and Evolutionary Biology, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China)

机构地区：[1]上海交通大学农业与生物学院,上海200240 [2]中国科学院上海植物生理生态研究所昆虫发育与进化生物学重点实验室,上海200032

出　　处：《中国科学：生命科学》2018年第5期562-570,共9页Scientia Sinica(Vitae)

摘　　要：冬虫夏草为冬虫夏草菌(Ophiocordyceps sinensis)感染蝙蝠蛾(Thitarodes spp.)幼虫后形成的菌虫复合体.本文在前期完成冬虫夏草菌基因组研究的基础上,于青藏高原5个不同样地采样,取虫草子实体部分开展宏转录组分析.结果表明,不同样品中的微生物群落组成不同,但真菌寄生菌——木霉菌(Trichoderma spp.)存在于所有样品中.使用测序片段进行编码基因比对及基因差异表达分析表明,不同基因的表达水平在不同样品中存在显著差异,尤其是与真菌有性生殖及子实体发育等相关基因的表达存在明显差异,但总体特征与样品采集地的地理纬度相关.冬虫夏草菌基因组中的转座子元件显著扩张,宏转录组分析表明,Ⅰ型反转录元件及Ⅱ型DNA转座子在不同样品中均存在高水平的表达,暗示这些转座子参与冬虫夏草菌的环境适应性调控及基因组进化.The caterpillar fungus（i.e., the insect-fungus complex） is formed when the ghost moth（Thitarodes spp.） larvae have been infected and killed by the fungus Ophiocordyceps sinensis. After finishing the genomics study of O. sinensis, we performed metatranscriptomics analysis of the caterpillar fungal samples collected from five places within the Qinghai-Tibetan Plateau. The fruiting-bodies were dissected for total RNA isolation and RNA-seq analysis. It was found that diversified microbial communities were present in different samples and interestingly, the mycoparasites Trichoderma spp. were found ubiquitously present in all samples. By mapping the reads to the genes encoded by O. sinensis, gene differential expression profiling revealed that the environmental gene expression patterns varied between samples but were correlated with the field altitudes from where the samples had been collected. In particular, the genes involved in sexuality and fruiting-body development controls were differentially expressed in different samples, indicating that the fungus might develop at varied stages at the sampling dates. The transposable elements（TEs）are expanded in the genome of O. sinensis. Our metatranscriptomics analysis demonstrated that massive transcriptions of the Class I type of retrotransposons and Class II type of DNA transposons were detected in all five samples. In addition to contributing to environmental adaptation, active expression of these TEs could drive the rapid evolution of fungal genomes.

关 键 词：冬虫夏草 宏转录组 子实体发育 有性生殖 转座子 基因差异表达 

分 类 号：S567.35[农业科学—中草药栽培]