Development Of Microsatellite Markers And Genetic Diversity In Exopalaemon Carinicauda

A microsatellite-enriched library of the ridgetail white prawn(Exopalaemoncarinicauda) was constructed using the method of magnetic bead hybridizationenrichment. Genomic DNA of ridgetail white prawn was digested with the restrictionendonuclease HaeIII. DNA fragments from400to1,200bp were recycled and ligatedto HaeIII adaptors.The ligated DNA fragments were hybridized with biotinylatedprobe (AG)15. Then, enriched DNA fragments were ligated to pMD18-T vector.947clones were randomly picked and screened by colony PCR.667clones were positive.184clones were randomly selected and sequenced from positive clones.150cloneswere found to contain199microsatellite sequences. Among these microsatellites,79.4%were perfect type,13.6%were imperfect type and7.0%were compound type.From the primers designed for the119microsatellite loci,64could amplify expectedPCR products and26were found to be polymorphic．The number of alleles at eachlocus ranged from3to16. The observed and expected heterozygosities varied from0.111to0.929and from0.246to0.932, respectively. The PIC value ranged from0.231to0.909. These new loci will be useful in the study of population geneticstructure and conservation in this species.In this study, thirty microsatellite loci were isolated and characterized for theridgetail white prawns, E. carinicauda in Laizhou bay by microsatellite-enrichedlibrary. Polymorphisms were tested in30individuals from a single wild population.The number of alleles at each locus ranged from2to14. The observed and expectedheterozygosities varied from0.1000to0.8000and from0.2299to0.9228,respectively. The PIC value ranged from0.2002to0.8939. These new loci will beuseful in the study of population genetic structure and genetic diversity in this species.Genetic diversity of3wild stocks,collected from Laizhuo Bay(LZ),HaizhuoBay(HZ),Xiangshang(XS), were investigated using12microsatellite loci. A total of115alleles were detected in12microsatellite loci and the number of alleles ranged from6to14(mean9.5833). The expected and observed heterozygosities in12lociranging from0.7653to0.8660(mean0.8278) and from0.2167to0.7176(mean0.5175), respectively. The average polymorphic information content of12loci was0.7051. Mean coefficient of gene differentiation for loci(Fst) was0.0930(0.05<Fst<0.15)by F-statistics. UPGMA clustering tree based on D geneticdistance showed that Laizhuo Bay stock was more closely related to Xiangshangstock and Haizhuo Bay stock was farthest related to Xiangshang stock.By selecting10pairs of polymorphic microsatellite markers of Exopalaemoncarinicauda, the multiplex PCR amplification system was built.