title: Senescence is accelerated through donor cell specificity in cloned pigs.
abstract: Animals cloned by somatic cell nuclear transfer (SCNT) sometimes have abnormalities             that result in large offspring syndrome or early death during gestation due to             respiratory and metabolic defects. We cloned pigs using two sources of donor cells             and observed phenotypic anomalies in three pigs cloned from one type of cell,             s-pig fetal fibroblasts. These animals had many wrinkles on their faces and bodies             and looked older than age-matched normal pigs. We performed the present study             to examine whether the wrinkled phenotype in the cloned pigs was due to senescence,             a genetic problem with donor specificity, or epigenetic problems with reprogramming.             To address this issue, we investigated biomarkers of senescence, including telomere             length and the expression of senescence-associated β-galactosidase (SA-β-gal),             glyceraldehyde phosphate dehydrogenase (GAPDH) and β-actin. We also assessed the             methylation status of euchromatic PRE-1 repetitive sequences and centromeric satellite             DNA, and measured the mRNA levels of six imprinted genes, Copg2, Mest, Igf2R,             GNAS, SNRPN and Ube3a. The telomeres of the wrinkled cloned pigs were much shorter             than those of the normal cloned pigs and age-matched normal pigs. In the wrinkled             cloned pigs, SA-β-gal activity was detected and GAPDH and β-actin were repressed.             The mRNA levels of Mest, GNAS and Ube3a were reduced in the wrinkled cloned pigs,             although there was no difference between the normal cloned pigs and normal controls.             This gene expression analysis indicates that the wrinkled abnormality of our pigs             originates from genetic abnormalities in the donor cells used for SCNT.
authors.affiliation: Sooam Biotech Research Foundation, Guro-gu, Seoul 152-904, Republic                     of Korea.
authors.forename: Hyun Yong
authors.initials: HY
authors.lastname: Jeon
authors.forename: Yeon Woo
authors.initials: YW
authors.lastname: Jeong
authors.forename: Yeon Wook
authors.initials: YW
authors.lastname: Kim
authors.forename: Yeon Ik
authors.initials: YI
authors.lastname: Jeong
authors.forename: Shamim M
authors.initials: SM
authors.lastname: Hossein
authors.forename: Hyun
authors.initials: H
authors.lastname: Yang
authors.forename: Sang Hwan
authors.initials: SH
authors.lastname: Hyun
authors.forename: Eui-Bae
authors.initials: EB
authors.lastname: Jeung
authors.forename: Woo Suk
authors.initials: WS
authors.lastname: Hwang
mesh_terms: D000375:Aging / Q000235:genetics*; D000818:Animals; D019976:Cloning, Organism; D019175:DNA Methylation; D004276:DNA, Satellite / Q000378:metabolism; D005260:Female; D018392:Genomic Imprinting; D053652:Nuclear Transfer Techniques; D010641:Phenotype; D013552:Swine; D016615:Telomere / Q000378:metabolism; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D004276:DNA, Satellite; D001616:beta-Galactosidase