草菇基因组中的tRNA分析

Analysis of the tRNA Genes in the Volvariella volvacea Genome

草菇(Volvariella volvacea),又名中国蘑菇,是一种生长于中国和东南亚的重要经济食用菌。本文基于本实验室的草菇基因组测序结果,分析了草菇基因组中的tRNA情况。草菇基因组的302个框架中,共发现了177个tRNA基因,其中有7个可能的假基因,有2个携带硒代半胱氨酸,一个抑制性tRNA基因和一个未知的异型结构tRNA。除了上述11个特殊的tRNA基因外,166个tRNA可按反密码子类型分成47类。与其它5种担子菌的基因组tRNA比较,草菇的tRNA数量处于第4位,少于鬼伞、裂褶菌、灵芝,多于双孢蘑菇和平菇。通过比较分析草菇及这5种大型真菌的基因组tRNA编码情况,首次报道了几种食用菌tRNA遵守修正的摆动假说的情况。另外,草菇的同功受体tRNA非编码子序列也具有差异性,对tRNA的分析将有助于进一步研究草菇的进化。

Volvariella volvacea, the Chinese mushroom, is a commercially important edible fungus grown in China and southeast Asia. Using genome sequencing, one hundred and seventy seven tRNA genes were identified in 302 scaffolds of V. volvacea, including seven putative pseudogenes, two genes carrying selenocysteine, an inhibitor of tRNA genes, and finally, an undetermined isotype oftRNA. The remaining 166 tRNA genes were classified into 47 categories based on their anticodons. Comparison with tRNA profiles from the other five basidiomycete genomes revealed that V. volvacea ranked fourth in terms of the number of genes encoding tRNA, following Coprinus cinereus, Schizophyllum commune, and Ganderrna lucidura but ahead of A garieus bisporus and Pleurotus ostreatus. In addition, the composition oftRNA in Volvariella volvacea and these other five basidiomycetes validates the modified wobble hypothesis. Analysis of the isoacceptor tRNA species demonstrated that they were different, which indicates the significance of this tRNA in further studies to analyze the evolution of V. volvaeea.