组学技术揭秘草食动物消化道真菌组成和功能

真菌是挖掘高效纤维降解酶的核心微生物。厌氧真菌能特化出氢化酶体和纤维小体结构，提高厌氧环境下自身的能量供应；也能特化出厚的细胞壁或孢子样结构增强对不良环境的适应。畜种和消化道类型、日粮结构均能影响消化道真菌的组成。基于核糖体18S/28S rRNA基因和转录组间隔区（internal spacer region, ITS）的分子标记技术为厌氧真菌数量和区系研究提供了更为精准的手段，使厌氧真菌的研究逐渐深入。28S rDNA的D1/D2 区域是厌氧真菌高通量分析的首选。由于目前组学分析数据库中缺少真菌的信息，以及很难直接从消化道内容物中获取足量的真菌DNA/RNA用于宏基因组/宏转录组分析，所以基于宏基因组学/宏转录组学技术揭示消化道内真菌生理和功能的研究非常有限，是今后真菌研究应重点突破的领域。 通讯作者: 王佳堃（https://orcid.org/0000-0002-7213-3721） E-mail: jiakunwang@zju.edu.cn
Abstract: Fungi are the major microbes to exploit fiber degrading enzymes. Anaerobic fungi possess hydrogenosomes and cellulosomes to improve their energy supply in anaerobic environment, and their thick cell wall or spore-like structure help them adapt adverse environment. Animal host phylogeny and diet exert the most significant role in shaping anaerobic fungal diversity and community structure. Molecular marker technology based on ribosomal 18S/28S rRNA genes and internal spacer region (ITS) provides a more precise means for the research of anaerobic fungi quantity and diversity, and the 28S rDNA D1/D2 is the preferred region for anaerobic fungal next generation sequencing. Due to limited databases for fungus and methods for obtaining enough fungal DNA/RNA from digestive tract contents for metagenomic/metatranscriptomic analyses, little work is available on fungal physiology and function of gastrointestinal tract using advanced omics techniques. However, application of these techniques will be key to deepen our understanding of the ecological role of fungi in gastrointestinal tract. Key words: anaerobic fungi gastrointestinal tract phylogeny molecular marker metatranscriptomics