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The complete mitochondrial genome sequence of Takydromus septentrionalis was determined by shotgun sequencing. The total length of mitogenome is 18,304 bp, and contains 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes, and 2 control regions. Most of the genes of T. septentrionalis were distributed on the H-strand, except for the ND6 subunit gene and eight tRNA genes which were encoded on the L-strand. The phylogenetic tree of T. septentrionalis and 8 other closely related species was reconstructed. The phylogenetic analyses based on these mitogenomes presented here will be useful for further insights on the evolutionary relationships of Takydromus. [ABSTRACT FROM AUTHOR]

The Chung-an ground lizard Takydromus sylvaticus is an endemic and long-lost reptile species in China. In this study, its mitochondrial genome (mitogenome) sequence was firstly determined by long PCR and primer walking methods. The genome is 17,838 bp long and contains 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 2 main noncoding regions (the control region and the putative L-strand replication origin). The gene order and contents in the T. sylvaticus mitogenome is identical to that found in typical vertebrates, suggesting that it represents an ancestral arrangement. Within the control region, typical conserved domains and distinct repeat regions were identified. [ABSTRACT FROM AUTHOR]

Six main mitochondrial DNA (mtDNA) lineages have been described in minnow (Zacco platypus) samples obtained from northern, western and southern China. Perdices et al. (2004) predicted that further sampling of other tributaries might discover more lineages of this species. In this study, we collected 26 Zacco platypus individuals in the Huangshan area of eastern China and determined the cytochrome b (cytb) sequence variations. Combined with reported data in GenBank, we identified ten matrilines (Zacco A-J) in a total of 169 samples, with relatively high molecular divergence found among them. The Huangshan population had the greatest genetic variation among all sampled regions and hosted six of the ten matrilines. Our results highlight the significance of the Huangshan area for the conservation of Zacco platypus.

Cytochrome b (cyt b) gene complete sequences (1143bp) of Takydromus sylvaticus were sequenced. In order to clarify the phylogenetic position of the Takydromus sylvaticus, we investigated the phylogeny of 15 Takydromus spp. distributed in East-Asia by Maximum Parsimony (MP), Bayesian Inference (BI), and Maximum Likelihood (ML) methods using DNA fragments of cyt b genes. The results supported that the Platyplacopus merged into Takydromus and negated the validity of Platyplacopus. Furthermore, the prediction of tertiary structures of cyt b exhibited the CD loop region contain two short helices forming a hairpin arrangement, namely cd1 and cd2. Thermostability analysis shows that the CD-loop region is unstable thermodynamically and may provide mobility to amino acids located at the heme, and might provide high flexibility to the top of ISP (iron-sulfur protein) and the cavity region of Qo binding site. It suggested that the two short helices of CD loop region of cyt b was a dominating portion for ISP binding site.