Gene expression variations in high-altitude adaptation: a case study of the Asiatic toad (Bufo gargarizans)

BMC Genetics

Research Article

Yayong Wu¹  Bin Lu¹  Weizhao Yang¹  Yin Qi¹  Liang Qiao¹  Jinzhong Fu² 

[1] Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, China;Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, China;Department of Integrative Biology, University of Guelph, N1G 2W1, Guelph, ON, Canada;

关键词: High-altitude;    Toads;    Gene expression;    Down-regulation;    Nutrient metabolism;    Cardiac functions;   

DOI  :  10.1186/s12863-017-0529-z

 received in 2016-12-28, accepted in 2017-06-23,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundGenome-wide investigation of molecular mechanisms for high-altitude adaptation has attracted great attention in the last few years. In order to understand the contribution of gene expression level variations to high-altitude adaptation in Asiatic toads (Bufo gargarizans), we implemented a reciprocal transplant experiment between low- and high-altitude sites and sequenced 12 transcriptomes from brain, heart, and liver tissues.ResultsA large number of genes with expression differences (DEGs) between high- and low-altitude individuals (193 fixed and 844 plastic) were identified, and the majority of them were tissue specific. Heart displayed the largest number of DEGs, both plastic and fixed. Fixed DEGs were particularly concentrated in functions associated with muscle contraction, and the majority of them were down-regulated in high-altitude individuals. Plastic DEGs were highly concentrated in several energy metabolism related functional categories, and the majority of them were also down-regulated at high-altitude environments. In liver samples, genes associated with nutrient metabolism experienced a broad-scale expression down-regulation in high-altitude toads.ConclusionsThese broadly suppressed expression patterns at high altitudes are in strong contrast to those of endothermic homeotherms, suggesting poikilothermic vertebrates may have adopted different strategies at high altitudes. Our results strongly support that both genotypic specialization and phenotypic plasticity play crucial role in adaptation to high altitude for Asiatic toads. Poikilothermic vertebrates are among the most hypoxia-tolerant animals known, and many molecular mechanisms remain elusive. We hope that our results will provide useful directions for future research.

【 授权许可】

CC BY   
© The Author(s). 2017