title: Proteomic analysis of the extraembryonic tissue from cloned porcine embryos.
abstract: Cloned animals developed from somatic cell nuclear transfer (SCNT) embryos are useful resources for agricultural and medical applications. However, the birth rate in the cloned animals is very low, and the cloned animals that have survived show various developmental defects. In this report, we present the morphology and differentially regulated proteins in the extraembryonic tissue from SCNT embryos to understand the molecular nature of the tissue. We examined 26-day-old SCNT porcine embryos at which the sonogram can first detect pregnancy. The extraembryonic tissue from SCNT embryos was abnormally small compared with the control. In the proteomic analysis with the SCNT extraembryonic tissue, 39 proteins were identified as differentially regulated proteins. Among up-regulated proteins, Annexins and Hsp27 were found. They are closely related to the processes of apoptosis. Among down-regulated proteins, Peroxiredoxins and anaerobic glycolytic enzymes were identified. In the Western blot analysis, antioxidant enzymes and the antiapoptotic Bcl-2 protein were down-regulated, and caspases were up-regulated. In the terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) assay with the placenta from SCNT embryos, apoptotic trophoblasts were observed. These results demonstrate that a major reason for the low birth rate of cloned animals is due to abnormal apoptosis in the extraembryonic tissue during early pregnancy.
authors.affiliation: Centre for Development and Differentiation, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-333, Korea.
authors.forename: Jung-Il
authors.initials: JI
authors.lastname: Chae
authors.forename: Seong-Keun
authors.initials: SK
authors.lastname: Cho
authors.forename: Jung-Woo
authors.initials: JW
authors.lastname: Seo
authors.forename: Tae-Sung
authors.initials: TS
authors.lastname: Yoon
authors.forename: Kyu-Sun
authors.initials: KS
authors.lastname: Lee
authors.forename: Jin-Hoi
authors.initials: JH
authors.lastname: Kim
authors.forename: Kyung-Kwang
authors.initials: KK
authors.lastname: Lee
authors.forename: Yong-Mahn
authors.initials: YM
authors.lastname: Han
authors.forename: Kweon
authors.initials: K
authors.lastname: Yu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D004622:Embryo, Mammalian / Q000378:metabolism*; D005321:Extraembryonic Membranes / Q000378:metabolism*; D005260:Female; D008297:Male; D053652:Nuclear Transfer Techniques; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013552:Swine / Q000196:embryology*
chemical_list: D011257:Pregnancy Proteins; D020543:Proteome; D053148:Caspase 3; D020169:Caspases