title: Knockdown of myostatin expression by RNAi enhances muscle growth in transgenic sheep.
abstract: Myostatin (MSTN) has been shown to be a negative regulator of skeletal muscle development and growth. MSTN dysfunction therefore offers a strategy for promoting animal growth performance in livestock production. In this study, we investigated the possibility of using RNAi-based technology to generate transgenic sheep with a double-muscle phenotype. A shRNA expression cassette targeting sheep MSTN was used to generate stable shRNA-expressing fibroblast clones. Transgenic sheep were further produced by somatic cell nuclear transfer (SCNT) technology. Five lambs developed to term and three live lambs were obtained. Integration of shRNA expression cassette in three live lambs was confirmed by PCR. RNase protection assay showed that the shRNAs targeting MSTN were expressed in muscle tissues of three transgenic sheep. MSTN expression was significantly inhibited in muscle tissues of transgenic sheep when compared with control sheep. Moreover, transgenic sheep showed a tendency to faster increase in body weight than control sheep. Histological analysis showed that myofiber diameter of transgenic sheep M17 were bigger than that of control sheep. Our findings demonstrate a promising approach to promoting muscle growth in livestock production.
authors.affiliation: College of Animal Science and Technology, Shihezi University, Shihezi, China.
authors.forename: Shengwei
authors.initials: S
authors.lastname: Hu
authors.forename: Wei
authors.initials: W
authors.lastname: Ni
authors.forename: Wujiafu
authors.initials: W
authors.lastname: Sai
authors.forename: Ha
authors.initials: H
authors.lastname: Zi
authors.forename: Jun
authors.initials: J
authors.lastname: Qiao
authors.forename: Pengyang
authors.initials: P
authors.lastname: Wang
authors.forename: Jinliang
authors.initials: J
authors.lastname: Sheng
authors.forename: Chuangfu
authors.initials: C
authors.lastname: Chen
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D001835:Body Weight / Q000235:genetics / Q000502:physiology; D019976:Cloning, Organism; D015870:Gene Expression; D055785:Gene Knockdown Techniques; D018482:Muscle, Skeletal / Q000254:growth & development*; D018006:Myogenic Regulatory Factors / Q000235:genetics; D055435:Myostatin / Q000037:antagonists & inhibitors* / Q000235:genetics* / Q000502:physiology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D034561:Sheep, Domestic / Q000235:genetics* / Q000254:growth & development* / Q000502:physiology
chemical_list: D018006:Myogenic Regulatory Factors; D055435:Myostatin; D034741:RNA, Small Interfering