Differential Expression of Genes Involved in Host Recognition, Attachment, and Degradation in the Mycoparasite Tolypocladium ophioglossoides.
Differential Expression of Genes Involved in Host Recognition, Attachment, and Degradation in the Mycoparasite Tolypocladium ophioglossoides.
复制标题
DOI：
10.1534/g3.116.027045
复制
发表时间：
2016-01-22
期刊：
影响因子：
--
通讯作者：
Spatafora JW
中科院分区：
文献类型：
--
作者：
Quandt CA;Di Y;Elser J;Jaiswal P;Spatafora JW
真菌感染新宿主的能力取决于基因含量、表达或调控的变化。在模拟宿主条件下检测基因表达可以探索哪些基因可能有助于宿主跳跃。昆虫致病性是推断的Tolypocladium物种的祖先特征状态，然而几个物种是块菌的寄生虫，包括Tolypocladium ophioglossoides。为了确定这种界际宿主转换中潜在的关键基因，T。ophioglossoides在四种培养基条件下生长：含有其天然宿主（锦蛇的块菌）的内部和外部部分的培养基、来自祖先宿主（甲虫）的库蚊和丰富的培养基（酵母麦芽）。通过对这些条件下mRNA的高通量RNASeq，在实验中鉴定了许多差异表达的基因。这些包括PTH11相关的G蛋白偶联受体（GPCR），假设参与宿主识别，也发现在昆虫病原体中上调。还发现具有信号肽的发散几丁质酶在含有块菌组织的培养基上高度上调，表明在块菌宿主存在下的外源降解活性。粘附素基因Mad1在块菌培养基上也高度表达。BiNGO分析了在每种生长条件下表达的基因中过度表达的GO术语，发现参与氧化还原反应和跨膜转运的基因在T. ophioglossoides生长在块菌培养基上，表明它们在真菌组织上生长的重要性，与其他宿主和环境相比。次生代谢相关基因在昆虫组织生长过程中表达量最高，表明它们的产物可能不是锦蛇寄生所必需的。这项研究为理解从昆虫寄生到块菌寄生的遗传机制提供了线索。
The ability of a fungus to infect novel hosts is dependent on changes in gene content, expression, or regulation. Examining gene expression under simulated host conditions can explore which genes may contribute to host jumping. Insect pathogenesis is the inferred ancestral character state for species of Tolypocladium, however several species are parasites of truffles, including Tolypocladium ophioglossoides. To identify potentially crucial genes in this interkingdom host switch, T. ophioglossoides was grown on four media conditions: media containing the inner and outer portions of its natural host (truffles of Elaphomyces), cuticles from an ancestral host (beetle), and a rich medium (Yeast Malt). Through high-throughput RNASeq of mRNA from these conditions, many differentially expressed genes were identified in the experiment. These included PTH11-related G-protein-coupled receptors (GPCRs) hypothesized to be involved in host recognition, and also found to be upregulated in insect pathogens. A divergent chitinase with a signal peptide was also found to be highly upregulated on media containing truffle tissue, suggesting an exogenous degradative activity in the presence of the truffle host. The adhesin gene, Mad1, was highly expressed on truffle media as well. A BiNGO analysis of overrepresented GO terms from genes expressed during each growth condition found that genes involved in redox reactions and transmembrane transport were the most overrepresented during T. ophioglossoides growth on truffle media, suggesting their importance in growth on fungal tissue as compared to other hosts and environments. Genes involved in secondary metabolism were most highly expressed during growth on insect tissue, suggesting that their products may not be necessary during parasitism of Elaphomyces. This study provides clues into understanding genetic mechanisms underlying the transition from insect to truffle parasitism.