The Complete Mitochondrial Genome of Glyptothorax macromaculatus Provides a Well-Resolved Molecular Phylogeny of the Chinese Sisorid Catfishes

Abstract

Previous phylogenetic analyses of the Chinese sisorid catfishes have either been poorly resolved or have not included all the 12 sisorid genera. Here, we successfully assembled the first complete mitochondrial genome of the sisorid fish Glyptothorax macromaculatus. Based on this novel mitochondrial genome and previously published mitochondrial genomes in the Sisoridae, we generated maximum likelihood and Bayesian phylogenies. We dated our preferred topology using fossil calibration points. We also tested the protein-coding genes in the mitochondrial genomes of the glyptosternoid fishes for signals of natural selection by comparing the nucleotide substitution rate along the branch ancestral to the glyptosternoid fishes to other branches in our topology. The mitochondrial sequence structure of G. macromaculatus was similar to those known from other vertebrates, with some slight differences. Our sisorid phylogenies were well-resolved and well-supported, with exact congruence between the different phylogenetic methods. This robust phylogeny clarified the relationships among the Chinese sisorid genera and strongly supported the division of the family into three main clades. Interestingly, the glyptosternoid divergence time predicted by our molecular dating analysis coincided with the uplift of the Tibetan Plateau, suggesting that geology may have influenced speciation in the Sisoridae. Among the mitochondrial protein-coding genes, atp8 may have most rapidly evolved, and atp6 may have been subjected to positive selection pressure to adapt to high elevations. In summary, this study provided novel insights into the phylogeny, evolution and high-altitude adaptions of the Chinese sisorid fishes.

The complete mitochondrial genome of the intertidal spider (Desis jiaxiangi) provides novel insights into the adaptive evolution of the mitogenome and the evolution of spiders

“…The atp8 gene with the highest averages of both Ka and Ka/Ks suggests more changes in amino acids. This is also consistent with the previously identified Ka/Ks ratios in other spiders [37], insects [36] and fishes [38]. The higher Ka/Ks values indicate that the atp8 gene might have experienced more relaxed selective constraints and accumulated more mutations, thus it would be more likely to lose its function [36].…”

Mitochondrial genome annotation and phylogenetic placement of Oreochromis andersonii and O. macrochir among the cichlids of southern Africa

“…Evidence of positive selection, though not very common, has been observed in some fishes [ 55 , 56 ], in horses [ 57 , 58 ] and in insects [ 59 ]. Other studies have shown the important role the mitogenome plays in adapting to new environments as reviewed in Castellana et al 2011 [ 60 ].…”

Phylogenetic Relationships and Adaptation in Deep-Sea Mussels: Insights from Mitochondrial Genomes

“…The ATP synthase F o subunit 6 or complex V drives the last step of oxidative phosphorylation for electron transport chain. Evidence supporting the adaptive evolution of the atp6 gene has been reported in the mitogenome of Glyptothorax macromaculatus [ 47 ], deep-sea fish [ 19 ], and deep-sea polynoids [ 20 ]. Although cob is a conserved gene, it is crucial to the ability of the mitochondria to generate energy through reversible electron transfer from ubiquinol to cytochrome c along with proton translocation.…”