基于核苷酸序列及RNA二级结构基础的针层孔菌属(Phellinus)复合种分类学研究

Molecular Phylogeny of Species Complex of Phellinus Based on Nucleotide Sequences and RNA Secondary Structure

利用真菌核糖体核苷酸序列信息及RNA二级结构特征对针层孔菌属(Phellinus)复合种进行分类学研究。通过分析国内外已报道的一些针层孔菌属及其近缘属真菌核糖体DNA内转录间隔区(Internaltranscribed spacer,ITS)序列、线粒体核糖体小亚基DNA(Mitochondrial small subunit ribosomal DNA,mtSSU rDNA)序列,分别构建系统进化树,并基于最小自由能原理分析RNA二级结构,结果显示松针层孔菌(Phellinus pini)不同菌株的序列差异极小,其可能并非复合种,而火木针层孔菌(Phellinus igniarius)可能包含更多的种,且这些种序列变异较大,其分类地位较复杂。

Molecular phylogeny of species complex ofPhellinus was studied based on nucleotide sequences of ribosome of fungus and the characterization of RNA secondary structure. Some sequences of internal transcribed spacer （ITS） and mitochondrial small subunit ribosomal DNA （mt SSU rDNA） forPhellinus and related species were analyzed, and phylogenetic trees were constructed. In addition, the RNA secondary structures were also studied based on free energy minimization. The result showed that the characterization of sequences for different strains ofPhellinus pini was similar,Phellinus pini was not likely to be a specie complex.Phellinus igniarius could comprise more species, which had different characterizations of sequences, so it was difficult to separate the species complex in taxonomy.