Cai Yin-Yin, Shen Shi-Qi, Lu Li-Xu, Storey Kenneth B, Yu Dan-Na, Zhang Jia-Yong
College of Chemistry and Life Science, Zhejiang Normal University, Jinhua, Zhejiang, China.
Department of Biology, Carleton University, Ottawa, ON, Canada.
PeerJ. 2019 Aug 23;7:e7532. doi: 10.7717/peerj.7532. eCollection 2019.
The family Pyxicephalidae including two subfamilies (Cacosterninae and Pyxicephalinae) is an ecologically important group of frogs distributed in sub-Saharan Africa. However, its phylogenetic position among the Anura has remained uncertain. The present study determined the complete mitochondrial genome sequence of , the first representative mitochondrial genome from the Pyxicephalinae, and reconstructed the phylogenetic relationships within Ranoidae using 10 mitochondrial protein-coding genes of 59 frog species. The mitochondrial genome showed major gene rearrangement and an exceptionally long length that is not shared with other Ranoidae species. The genome is 24,317 bp in length, and contains 15 protein-coding genes (including extra and genes), four rRNA genes (including extra and genes), 29 tRNA genes (including extra , , , , , , genes) and two control regions (CRs). The Dimer-Mitogenome and Tandem duplication and random loss models were used to explain these gene arrangements. Finally, both Bayesian inference and maximum likelihood analyses supported the conclusion that Pyxicephalidae was monophyletic and that Pyxicephalidae was the sister clade of (Petropedetidae + Ptychadenidae).
姬蛙科包括两个亚科(短头蛙亚科和姬蛙亚科),是分布于撒哈拉以南非洲的一类具有重要生态意义的蛙类。然而,它在无尾目中的系统发育位置一直不确定。本研究测定了姬蛙亚科首个代表性线粒体基因组—— 的完整线粒体基因组序列,并利用59种蛙类的10个线粒体蛋白质编码基因重建了蛙科内部的系统发育关系。 线粒体基因组显示出主要的基因重排和极长的长度,这与其他蛙科物种不同。该基因组长度为24317 bp,包含15个蛋白质编码基因(包括额外的 和 基因)、4个rRNA基因(包括额外的 和 基因)、29个tRNA基因(包括额外的 、 、 、 、 、 、 基因)和两个控制区(CRs)。采用二聚体线粒体基因组模型和串联重复及随机丢失模型来解释这些基因排列。最后,贝叶斯推断和最大似然分析均支持姬蛙科是单系的这一结论,且姬蛙科是(岩蛙科 + 褶蛙科)的姐妹分支。