Laboratoire d'Ecologie Alpine, UMR 5553 UJF/CNRS, Université Joseph Fourier, Grenoble, France.
FEMS Microbiol Lett. 2010 Jan;302(1):76-84. doi: 10.1111/j.1574-6968.2009.01839.x. Epub 2009 Oct 28.
We explored the potential of the cox1 gene in the species resolution of soil fungi and compared it with the nuclear internal transcribed spacer (ITS) and small subunit (SSU)-rDNA. Conserved primers allowing the amplification of the fungal cox1 gene were designed, and a total of 47 isolates of Zygomycota and Ascomycota were investigated. The analysis revealed a lack of introns in >90% of the isolates. Comparison of the species of each of the six studied genera showed high interspecific sequence polymorphisms. Indeed, the average of nucleotide variations (4.2-11%) according to the genus, due mainly to the nucleotide substitutions, led to the taxonomic resolution of all the species studied regarding both ITS and SSU-rDNA, in which <88% were discriminated. The phylogenetic analysis performed after alignment of the cox1 gene across distant fungal species was in accordance with the well-known taxonomic position of the species studied and no overlap was observed between intra- and interspecific variations. These results clearly demonstrated that the cox1 sequences could provide good molecular markers for the determination of the species composition of environmental samples and constitute an important advance to study soil fungal biodiversity.
我们探索了cox1 基因在土壤真菌物种分辨率中的潜力，并将其与核内部转录间隔区（ITS）和小亚基（SSU）-rDNA 进行了比较。设计了允许扩增真菌 cox1 基因的保守引物，共研究了 47 株接合菌和子囊菌。分析表明，超过 90%的分离物中缺乏内含子。对所研究的六个属的每个种的比较显示出高度的种间序列多态性。实际上，由于核苷酸取代，根据属的平均核苷酸变化（4.2-11%）导致了所有研究种的分类分辨率，ITS 和 SSU-rDNA 的分辨度均<88%。在对cox1 基因进行跨远缘真菌物种的排列后进行的系统发育分析与所研究种的已知分类地位一致，并且没有观察到种内和种间变异之间的重叠。这些结果清楚地表明，cox1 序列可以为确定环境样本的物种组成提供良好的分子标记，并为研究土壤真菌生物多样性构成重要进展。
