RESEARCH ARTICLE Transcriptome Profiling and Molecular Pathway Analysis of Genes in Association with Salinity Adaptation in Nile Tilapia Oreochromis niloticus Zhixin Xu1, Lei Gan1, Tongyu Li1, Chang Xu1, Ke Chen1, Xiaodan Wang1, Jian G. Qin2, Liqiao Chen1*, Erchao Li1* 1 Laboratory of Aquaculture Nutrition and Environmental Health, School of Life Sciences, East China Normal University, 500 Dongchuan Rd., Shanghai 200241, China, 2 School of Biological Sciences, Flinders University, Adelaide, SA 5001, Australia *
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[email protected] (LC) Abstract Nile tilapia Oreochromis niloticus is a freshwater fish but can tolerate a wide range of salini- OPEN ACCESS ties. The mechanism of salinity adaptation at the molecular level was studied using RNA- Citation: Xu Z, Gan L, Li T, Xu C, Chen K, Wang X, Seq to explore the molecular pathways in fish exposed to 0, 8, or 16 (practical salinity unit, et al. (2015) Transcriptome Profiling and Molecular psu). Based on the change of gene expressions, the differential genes unions from freshwa- Pathway Analysis of Genes in Association with Salinity Adaptation in Nile Tilapia Oreochromis ter to saline water were classified into three categories. In the constant change category (1), niloticus. PLoS ONE 10(8): e0136506. doi:10.1371/ steroid biosynthesis, steroid hormone biosynthesis, fat digestion and absorption, comple- journal.pone.0136506 ment and coagulation cascades were significantly affected by salinity indicating the pivotal Editor: Marie-Joelle Virolle, University Paris South, roles of sterol-related pathways in response to salinity stress. In the change-then-stable cat- FRANCE egory (2), ribosomes, oxidative phosphorylation, signaling pathways for peroxisome prolif- Received: June 4, 2015 erator activated receptors, and fat digestion and absorption changed significantly with Accepted: August 4, 2015 increasing salinity, showing sensitivity to salinity variation in the environment and a responding threshold to salinity change.