title: Transcriptome analysis and SSR/SNP markers information of the blunt snout bream (Megalobrama amblycephala).
abstract: BACKGROUND
  Blunt snout bream (Megalobrama amblycephala) is an herbivorous freshwater fish species native to China and has been recognized as a main aquaculture species in the Chinese freshwater polyculture system with high economic value. Right now, only limited EST resources were available for M. amblycephala. Recent advances in large-scale RNA sequencing provide a fast, cost-effective, and reliable approach to generate large expression datasets for functional genomic analysis, which is especially suitable for non-model species with un-sequenced genomes.
  
  
  RESULTS
  Using 454 pyrosequencing, a total of 1,409,706 high quality reads (total length 577 Mbp) were generated from the normalized cDNA of pooled M. amblycephala individuals. These sequences were assembled into 26,802 contigs and 73,675 singletons. After BLAST searches against the NCBI non-redundant (NR) and UniProt databases with an arbitrary expectation value of E(-10), over 40,000 unigenes were functionally annotated and classified using the FunCat functional annotation scheme. A comparative genomics approach revealed a substantial proportion of genes expressed in M. amblycephala tanscriptome to be shared across the genomes of zebrafish, medaka, tetraodon, fugu, stickleback, human, mouse, and chicken, and identified a substantial number of potentially novel M. amblycephala genes. A total number of 4,952 SSRs were found and 116 polymorphic loci have been characterized. A significant number of SNPs (25,697) and indels (23,287) were identified based on specific filter criteria in the M. amblycephala.
  
  
  CONCLUSIONS
  This study is the first comprehensive transcriptome analysis for a fish species belonging to the genus Megalobrama. These large EST resources are expected to be valuable for the development of molecular markers, construction of gene-based linkage map, and large-scale expression analysis of M. amblycephala, as well as comparative genome analysis for the genus Megalobrama fish species. The identified SSR and SNP markers will greatly benefit its breeding program and whole genome association studies.
authors.affiliation: Key Lab of Freshwater Animal Breeding, College of Fisheries, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan, People's Republic of China.
authors.forename: Zexia
authors.initials: Z
authors.lastname: Gao
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.forename: Cong
authors.initials: C
authors.lastname: Zeng
authors.forename: Xiaolian
authors.initials: X
authors.lastname: Liu
authors.forename: Shaokui
authors.initials: S
authors.lastname: Yi
authors.forename: Weimin
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence / Q000235:genetics; D020451:Contig Mapping; D020869:Gene Expression Profiling; D005787:Gene Frequency / Q000235:genetics; D005819:Genetic Markers; D006801:Humans; D051379:Mice; D018895:Microsatellite Repeats / Q000235:genetics*; D058977:Molecular Sequence Annotation; D016366:Open Reading Frames / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D021541:Sea Bream / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D005819:Genetic Markers