title: Local adaptation of Gymnocypris przewalskii (Cyprinidae) on the Tibetan Plateau.
abstract: Divergent selection among environments affects species distributions and can lead to speciation. In this article, we investigated the transcriptomes of two ecotypes of scaleless carp (Gymnocypris przewalskii przewalskii and G. p. ganzihonensis) from the Tibetan Plateau. We used a transcriptome sequencing approach to screen approximately 250,000 expressed sequence tags (ESTs) from the gill and kidney tissues of twelve individuals from the Ganzi River and Lake Qinghai to understand how this freshwater fish has adapted to an ecological niche shift from saline to freshwater. We identified 9,429 loci in the gill transcriptome and 12,034 loci in the kidney transcriptome with significant differences in their expression, of which 242 protein-coding genes exhibited strong positive selection (Ka/Ks > 1). Many of the genes are involved in ion channel functions (e.g., Ca(2+)-binding proteins), immune responses (e.g., nephrosin) or cellular water absorption functions (e.g., aquaporins). These results have potentially broad importance in understanding shifts from saline to freshwater habitats. Furthermore, this study provides the first transcriptome of G. przewalskii, which will facilitate future ecological genomics studies and aid in the identification of genes underlying adaptation and incipient ecological speciation.
authors.affiliation: 1] Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China [2] University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Renyi
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Evolutionary Genetics, Leibniz Institute for Zoo and Wildlife Research, Berlin 10324, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Ludwig
authors.affiliation: Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China.
authors.forename: Cunfang
authors.initials: C
authors.lastname: Zhang
authors.affiliation: 1] Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China [2] University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Tong
authors.affiliation: 1] Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China [2] University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Guogang
authors.initials: G
authors.lastname: Li
authors.affiliation: 1] Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China [2] University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yongtao
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Southwest University School of Life Sciences, Chongqing 400715, China.
authors.forename: Zuogang
authors.initials: Z
authors.lastname: Peng
authors.affiliation: Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhao
mesh_terms: D000064:Acclimatization / Q000235:genetics*; D000818:Animals; D005075:Biological Evolution; D003530:Cyprinidae / Q000502:physiology*; D017753:Ecosystem; D019143:Evolution, Molecular; D005618:Fresh Water; D005786:Gene Expression Regulation / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D020543:Proteome / Q000235:genetics*; D054712:Salinity; D018609:Tibet; D059467:Transcriptome / Q000235:genetics*
chemical_list: D020543:Proteome