title: Comparative analysis of mitochondrial genomes in distinct nuclear ploidy loach Misgurnus anguillicaudatus and its implications for polyploidy evolution.
abstract: Misgurnus anguillicaudatus has several natural ploidy types. To investigate whether nuclear polyploidy have an impact on mitochondrial DNA (mtDNA), the complete mitochondrial genomes (mitogenomes) of five distinct ploidy M. anguillicaudatus (natural diploid, triploid, tetraploid, pentaploid and hexaploid), which were collected in central China, were sequenced and analyzed. The five mitogenomes share the same gene arrangement and have similar gene size, base composition and codon usage pattern. The most variable regions of the mitogenome were the protein-coding genes, especially the ND4L (5.39% mutation rate). Most variations occurred in tetraploids. The phylogenetic tree showed that the tetraploid M. anguillicaudatus separated early from other ploidy loaches. Meanwhile, the mitogenomes from pentaploids, and hexaploids have the closest phylogenetic relations, but far from that of tetraploids, implying that pentaploids and hexaploids could not be formed from tetraploids, possibly from the diploids and triploids. The genus Misgurnus species were divided into two divergent inter-genus clades, and the five ploidy M. anguillicaudatus were monophyletic, which support the hypotheses about the mitochondrial introgression in loach species.
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, P.R. China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Zhou
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, P.R. China.
authors.forename: Yongyao
authors.initials: Y
authors.lastname: Yu
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, P.R. China.
authors.forename: Yanhe
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, P.R. China.
authors.forename: Junjie
authors.initials: J
authors.lastname: Wu
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, P.R. China.
authors.forename: Xiujie
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Laboratorio de Biomedicina Molecular, Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Boulevard del Maestro esquina Elías Piña, Colonia Narciso Mendoza, Tamaulipas, Mexico.
authors.forename: Xianwu
authors.initials: X
authors.lastname: Guo
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, P.R. China.
authors.forename: Weimin
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D001482:Base Composition; D005075:Biological Evolution; D002874:Chromosome Mapping; D003062:Codon; D003531:Cypriniformes / Q000145:classification / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D014644:Genetic Variation; D054629:Genome, Mitochondrial; D010802:Phylogeny; D011003:Ploidies
chemical_list: D003062:Codon; D004272:DNA, Mitochondrial