title: LongSAGE analysis of skeletal muscle at three prenatal stages in Tongcheng and Landrace pigs.
abstract: BACKGROUND
  Obese and lean pig breeds show obvious differences in muscle growth; however, the molecular mechanism underlying phenotype variation remains unknown. Prenatal muscle development programs postnatal performance. Here, we describe a genome-wide analysis of differences in prenatal skeletal muscle between Tongcheng (a typical indigenous Chinese breed) and Landrace (a leaner Western breed) pigs.
  
  
  RESULTS
  We generated transcriptome profiles of skeletal muscle from Tongcheng and Landrace pigs at 33, 65 and 90 days post coitus (dpc), using long serial analysis of gene expression (LongSAGE). We sequenced 317,115 LongSAGE tags and identified 1,400 and 1,201 differentially expressed transcripts during myogenesis in Tongcheng and Landrace pigs, respectively. From these, the Gene Ontology processes and expression patterns of these differentially expressed genes were constructed. Most of the genes showed different expression patterns in the two breeds. We also identified 532, 653 and 459 transcripts at 33, 65 and 90 dpc, respectively, that were differentially expressed between the two breeds. Growth factors, anti-apoptotic factors and genes involved in the regulation of protein synthesis were up-regulated in Landrace pigs. Finally, 12 differentially expressed genes were validated by quantitative PCR.
  
  
  CONCLUSIONS
  Our data show that gene expression phenotypes differ significantly between the two breeds. In particular, a slower muscle growth rate and more complicated molecular changes were found in Tongcheng pigs, while genes responsible for increased cellular growth and myoblast survival were up-regulated in Landrace pigs. Our analyses will assist in the identification of candidate genes for meat production traits and elucidation of the development of prenatal skeletal muscle in mammals.
authors.affiliation: Department of Gene and Cell Engineering, State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100094, PR China.
authors.forename: Zhonglin
authors.initials: Z
authors.lastname: Tang
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Wan
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Li
authors.forename: Shuhong
authors.initials: S
authors.lastname: Zhao
authors.forename: Bang
authors.initials: B
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Fan
authors.forename: Mengjin
authors.initials: M
authors.lastname: Zhu
authors.forename: Mei
authors.initials: M
authors.lastname: Yu
authors.forename: Kui
authors.initials: K
authors.lastname: Li
mesh_terms: D000818:Animals; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D024510:Muscle Development; D018482:Muscle, Skeletal / Q000196:embryology* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D013045:Species Specificity; D034421:Sus scrofa / Q000196:embryology / Q000235:genetics*