Characterization of Complete Mitochondrial Genomes of the Five Peltigera and Comparative Analysis with Relative Species
In the present study, the complete mitochondrial genomes of five Peltigera species (P. elisabethae, P. neocanina, P. canina, P. ponojensis, P. neckeri) were sequenced, assembled and compared with relative species. The five mitogenomes were all composed of circular DNA molecules, and the length of five mitogenomes ranged from 58,132 bp to 69,325 bp. The mitochondrial genomes of five Peltigera species contain 15 protein-coding genes (PCGs), 2 rRNAs, 26-27 tRNAs and an unidentified open reading frame (ORF). The PCG length, AT skew and GC skew varied among the 15 PCGs in the five mitogenomes. Among 15 PCGs, cox2 had the least K2P genetic distance, indicating that the gene was highly conserved. The synteny analysis revealed that the coding regions were highly conserved in the Peltigera mitochondrial genomes, but gene rearrangement occurred in the intergenic regions. The phylogenetic analysis based on the 14 PCGs showed that the 11 Peltigera species formed well-supported topologies, indicating that the protein-coding genes in the mitochondrial genome can be used as a reliable molecular tool in the study of the phylogenetic relationship of Peltigera.