title: Identification of abnormal gene expression in bovine transgenic somatic cell nuclear transfer embryos.
abstract: This study was conducted to investigate the expression of three genes related to early embryonic development in bovine transgenic cloned embryos. To accomplish this, development of bovine transgenic somatic cell nuclear transfer (SCNT) embryos was compared with non-transgenic embryos. Next, mRNA transcription of three specific genes (DNMT1, Hsp 70.1, and Mash2) related to early embryo development in transgenic SCNT embryos was compared between transgenic and non-transgenic SCNTs, parthenogenetic embryos, and in vitro fertilization (IVF) embryos. Transgenic SCNT embryos showed significantly lower rates of development to the blastocyst stage than non-transgenic ones. To investigate normal gene expression, RNA was extracted from ten blastocysts derived from parthenogenesis, IVF, non-transgenic, and transgenic SCNT embryos and reverse-transcribed to synthesize cDNA. The cDNA was then subjected to PCR amplification and semi-quantified. More DNMT1 mRNA was detected in the transgenic SCNT group than the other three groups. Hsp 70.1 mRNA was detected in the IVF embryos, while lower levels were found in SCNT and parthenogenetic embryos. Mash2 mRNA was present at the highest levels in transgenic SCNT embryos. In conclusion, the higher levels of methylation and lower protein synthesis after heat shock in the transgenic SCNT embryos expected based on our results may cause lower embryonic development.
authors.affiliation: College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungnam National University, Daejeon 305-764, Korea.
authors.forename: Jongki
authors.initials: J
authors.lastname: Cho
authors.forename: Sungkeun
authors.initials: S
authors.lastname: Kang
authors.forename: Byeong Chun
authors.initials: BC
authors.lastname: Lee
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics* / Q000378:metabolism; D002417:Cattle / Q000196:embryology / Q000235:genetics*; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics* / Q000378:metabolism; D004622:Embryo, Mammalian / Q000196:embryology / Q000378:metabolism; D005260:Female; D005307:Fertilization in Vitro; D018507:Gene Expression Regulation, Developmental; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D053652:Nuclear Transfer Techniques / Q000662:veterinary; D010312:Parthenogenesis; D011247:Pregnancy; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger; C081884:heat-shock protein 70.1
keywords: bovine; development; embryo; gene expression; somatic cell nuclear transfer