title: iTRAQ-based quantitative proteomic analysis reveals the distinct early embryo myofiber type characteristics involved in landrace and miniature pig.
abstract: BACKGROUND
  Pig (Sus scrofa) is a major source of dietary proteins for human consumption and is becoming a valuable model in agricultural and biomedical research. The recently developed isobaric tag for relative and absolute quantitation (iTRAQ) method allows sensitive and accurate protein quantification. Here, we performed the first iTRAQ-based quantitative proteomic analyses of Landrace (LR) and Wuzhishan (WZS) pig longissimus dorsi muscle tissues during early embryonic development.
  
  
  RESULTS
  The iTRAQ-based early embryonic longissimus dorsi muscle study of LR and WZS ranging from 21 to 42 days post coitus (dpc) identified a total of 4431 proteins from 17,214 peptides, which were matched with 36,4025 spectra at a false discovery rate of 5%. In both WZS and LR, the largest amount of differentially expressed proteins (DEPs) were found between 28 and 35 dpc. 252 breed-DEPs were selected by GO analysis, including 8 myofibrillar proteins. Only MYHCI/IIA mRNA were detected due to early embryonic stages, and significantly higher expression of them were found in WZS during these 4 stages. MYHCI was first found in WZS at 28 dpc and expressed in both breeds at later stages, while MYHCII protein was not detected until 35 dpc in both breeds. Thus, 33 myogenic breed-DEPs selected from last two stages were analyzed by STRING, which showed that some myofibrillar proteins (MYH1, TPM4, MYH10, etc.) and functional proteins (CSRP2, CASQ2, OTC, etc.), together with candidate myogenic proteins (H3F3A, HDGFRP2, etc.), probably participate in the regulatory network of myofiber formation.
  
  
  CONCLUSIONS
  Our iTRAQ-based early embryonic longissimus dorsi muscle study of LR and WZS provides new data on the in vivo muscle development distinctions during early embryonic development, which contributes to the improved understanding in the regulation mechanism of early myogenesis in agricultural animals.
authors.affiliation: State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510006, Guangdong, China. zhangxum@mail2.sysu.edu.cn.
authors.forename: Xumeng
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510006, Guangdong, China. chyaosh@mail.sysu.edu.cn.
authors.forename: Yaosheng
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Guangdong Laboratory Animals Monitoring Institute, Guangzhou, 510663, Guangdong, China. jcpan@sina.com.
authors.forename: Jinchun
authors.initials: J
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510006, Guangdong, China. 277046330@qq.com.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510006, Guangdong, China. 303883617@qq.com.
authors.forename: Hu
authors.initials: H
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510006, Guangdong, China. etetjoe@qq.com.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510006, Guangdong, China. 276274942@qq.com.
authors.forename: Zhuning
authors.initials: Z
authors.lastname: Yuan
authors.affiliation: Guangdong Laboratory Animals Monitoring Institute, Guangzhou, 510663, Guangdong, China. wangxilonggd@163.com.
authors.forename: Xilong
authors.initials: X
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, 510006, Guangdong, China. modelin@mail.sysu.edu.cn.
authors.forename: Delin
authors.initials: D
authors.lastname: Mo
mesh_terms: D000818:Animals; D047108:Embryonic Development; D024510:Muscle Development; D018485:Muscle Fibers, Skeletal / Q000502:physiology*; D018482:Muscle, Skeletal / Q000196:embryology; D040901:Proteomics; D013552:Swine / Q000196:embryology; D013556:Swine, Miniature / Q000196:embryology