Genetic signals of high-altitude adaptation in amphibians: a comparative transcriptome analysis

BMC Genetics

Research Article

Yin Qi¹  Jinzhong Fu²  Weizhao Yang³ 

[1]Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, China

[2]Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, China

[3]Department of Integrative Biology, University of Guelph, N1G 2 W1, Guelph, ON, Canada

[4]Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, China

[5]Present address: Department of Biology, Lund University, 223 62, Lund, Sweden

关键词: Transcriptome;    High altitude;    Comparative analysis;    Positive selection;    F outlier analysis;    Nutrient metabolism;    Amphibians;    Asiatic toads;   

DOI  :  10.1186/s12863-016-0440-z

 received in 2016-03-08, accepted in 2016-09-20,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundHigh-altitude adaptation provides an excellent system for studying how organisms cope with multiple environmental stressors and interacting genetic modifications. To explore the genetic basis of high-altitude adaptation in poikilothermic animals, we acquired transcriptome sequences from a high-altitude population and a low-altitude population of the Asiatic toad (Bufo gargarizans). Transcriptome data from another high-altitude amphibian, Rana kukunoris and its low-altitude relative R. chensiensis, which are from a previous study, were also incorporated into our comparative analysis.ResultsMore than 40,000 transcripts were obtained from each transcriptome, and 5107 one-to-one orthologs were identified among the four taxa for comparative analysis. A total of 29 (Bufo) and 33 (Rana) putative positively selected genes were identified for the two high-altitude species, which were mainly concentrated in nutrient metabolism related functions. Using SNP-tagging and FST outlier analysis, we further tested 89 other nutrient metabolism related genes for signatures of natural selection, and found that two genes, CAPN2 and ITPR1, were likely under balancing selection. We did not detect any positively selected genes associated with response to hypoxia.ConclusionsAmphibians clearly employ different genetic mechanisms for high-altitude adaptation compared to endotherms. Modifications of genes associated with nutrient metabolism feature prominently while genes related to hypoxia tolerance appear to be insignificant. Poikilotherms represent the majority of animal diversity, and we hope that our results will provide useful directions for future studies of amphibians as well as other poikilotherms.

【 授权许可】

CC BY   
© The Author(s). 2016