Genome-Wide Scan for Positively Selected Genes in Sessile Molluscs Highlights the Genetic Basis for Their Adaptation to Attached Lifestyle

作     者：YU Hong LI Qi 

作者机构：Key Laboratory of Mariculture Ministry of Education Ocean University of China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and Technology 

出 版 物：《Journal of Ocean University of China》 (中国海洋大学学报（英文版）)

年 卷 期：2018年第17卷第4期

页      面：920-924页

核心收录：

学科分类：0908[农学-水产] 09[农学] 

基　　金：supported by the grants from the National Natural Science Foundation of China(No.3137 2524) the Shandong Seed Project,Shandong Province(No.2014GHY115002) the Fundamental Research Funds for the Central Universities(No.201762014) Qingdao National Laboratory for Marine Science and Technology(No.2016LMFS-A06) 

主　　题：molluscs adaptation evolution positive selection sessile lifestyle 

摘      要：Molluscs are one of the most diverse groups of animals and exhibit a rich and diverse variety of form and lifestyle. Most molluscs live with a free-moving lifestyle, while some molluscs are sessile. The adaptation to the two distinct lifestyles required complex changes, from molecules to organs, and physiology to morphology. In this study, we conducted a genome-wide scan for positive selection by comparing the available genomes of two sessile molluscs with four free-moving molluscs. A total of 40 genes were identified undergoing positive selection in the sessile molluscs by the branch-site model. Functional characterization showed that they were mainly enriched in two pathways, Oxidative phosphorylation(OXPHOS) and TGF-beta signaling pathway. The unexpected positive selection on OXPHOS genes in sessile molluscs suggests that the adaptation of OXPHOS involves many factors beyond enhancing ATP production. A modified OXPHOS regulatory system may allow sessile molluscs to better cope with biotic and abiotic stresses. Moreover, positively selected genes in TGF-beta signaling pathway probably have played a key role in the patterning of body plans and growth in metazoans. We speculate that these genes are associated with the body structure and organic adaptation to a sedentary lifestyle in sessile bivalve molluscs.