The Comparison Of Mitochondrial Genome Sequence And Phylogenetic Relationship Between Nine Species Of Turdus Thrushes

The avian genus Turdus(Passeriformes,Muscicapidae,Turdinae)is one of the most speciose and widespread of passerine genera.The phylogeny of the Turdus genus still remain controversial.We obtained the compete mitochondrial genome sequences of T.albocinctus,T.rubrocanus and T.kessleri through using polymerase chain reaction(PCR),long-and-accurate PCR(LA-PCR)and directly sequenced by primer walking.We downloaded the compete mitochondrial genome sequences of T.eunomus,T.hortulorum,T.merula,T.migratorius,T.philomelos,T.rufiventris,Ficedula zanthopygia,Ficedula albicollis and the sequences of 12 S rRNA and Cytb of 56 species of Turdus thrushes.We introduced the characteristics of complete mitochondrial genome of the T.albocinctus,T.rubrocanus and T.kessleri particularly,and made a comparision of the mitochondrial genome sequence between the nine Turdus species from different aspects.The result suggested that eight Turdus species except for T.philomelos contained 13 protein-coding genes,22 tRNA,2 rRNA and one control region.T.philomelos encoded 40 genes and two control regions.We made the analyses of bayesian and maximum likelihood,in which nine species from Turdus were selected as ingroups,and F.zanthopygia and F.albicollis were selected as outgrops.The topology of phylogenetic tree based on the two methods was consistent: 1.T.philomelos was located in the base of the trees relative to other eight Turdus species;2.T.migratorius and T.rufiventris clustered in a clade as a sister group;3.T.rubrocanus and T.albocinctus aggregated as a sister group and then clustered with T.eunomus,T.kessleri and T.hortulorum in a clade;4.The location of T.merula was different in the two kinds of phylogenetic trees.Then we made analyses of bayesian and maximum likelihood using mitochondrial DNA sequence from 12 S rRNA and cytochrome b genes.Our sampling included 59 Turdus species as ingroups and F.zanthopygia and F.albicollis as outgroups.The result showed that: 1.T.philomelos was still located in the base of the trees relative to other eight Turdus species;2.T.migratorius and T.nigrescens clustered in a clade as a sister group;3.T.hortulorum and T.cardis clustered in a clade as a sister group and then fall into a clade with T.dissimilis and T.unicolor;4.T.eunomus and T.ruficollis clustered in a clade as a sister group and then fall into a clade with T.torquatus;5.T.rubrocanus and T.albocinctus get together as a sister group;6.The relationship of T.kessleri and T.poliocephalus was close;7.T.rufiventris and T.grayi clustered in a clade;8.The location of T.merula was different in the two kinds of phylogenetic trees remain inconsistent,which still need further research.At last,we study the reliability of the single mitochondrial gene of 16 genes,including 13 PCGS,2 rRNA,and one D-loop region of nine Turdus species.The result revealed that 16 S rRNA and ND4 showed preferable solving ability in the phylogenetic relationship.