title: Population genetic studies revealed local adaptation in a high gene-flow marine fish, the small yellow croaker (Larimichthys polyactis).
abstract: The genetic differentiation of many marine fish species is low. Yet local adaptation may be common in marine fish species as the vast and changing marine environment provides more chances for natural selection. Here, we used anonymous as well as known protein gene linked microsatellites and mitochondrial DNA to detect the population structure of the small yellow croaker (Larimichthys polyactis) in the Northwest Pacific marginal seas. Among these loci, we detected at least two microsatellites, anonymous H16 and HSP27 to be clearly under diversifying selection in outlier tests. Sequence cloning and analysis revealed that H16 was located in the intron of BAHCC1 gene. Landscape genetic analysis showed that H16 mutations were significantly associated with temperature, which further supported the diversifying selection at this locus. These marker types presented different patterns of population structure: (i) mitochondrial DNA phylogeny showed no evidence of genetic divergence and demonstrated only one glacial linage; (ii) population differentiation using putatively neutral microsatellites presented a pattern of high gene flow in the L. polyactis. In addition, several genetic barriers were identified; (iii) the population differentiation pattern revealed by loci under diversifying selection was rather different from that revealed by putatively neutral loci. The results above suggest local adaptation in the small yellow croaker. In summary, population genetic studies based on different marker types disentangle the effects of demographic history, migration, genetic drift and local adaptation on population structure and also provide valuable new insights for the design of management strategies in L. polyactis.
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Le
authors.initials: L
authors.lastname: Wang
authors.affiliation: Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, China.
authors.forename: Shufang
authors.initials: S
authors.lastname: Liu
authors.affiliation: Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, Shandong, China.
authors.forename: Zhimeng
authors.initials: Z
authors.lastname: Zhuang
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Zining
authors.initials: Z
authors.lastname: Meng
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Haoran
authors.initials: H
authors.lastname: Lin
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000818:Animals; D004272:DNA, Mitochondrial / Q000235:genetics*; D051456:Gene Flow / Q000502:physiology*; D056426:Genetic Loci / Q000502:physiology; D018895:Microsatellite Repeats / Q000235:genetics*; D010473:Perciformes / Q000235:genetics*; D010802:Phylogeny
chemical_list: D004272:DNA, Mitochondrial