title: The HIST1 Locus Escapes Reprogramming in Cloned Bovine Embryos.
abstract: Epigenetic reprogramming is necessary in somatic cell nuclear transfer (SCNT) embryos in order to erase the differentiation-associated epigenetic marks of donor cells. However, such epigenetic memories often persist throughout the course of clonal development, thus decreasing cloning efficiency. Here, we explored reprogramming-refractory regions in bovine SCNT blastocyst transcriptomes. We observed that histone genes residing in the 1.5 Mb spanning the cow HIST1 cluster were coordinately downregulated in SCNT blastocysts. In contrast, both the nonhistone genes of this cluster, and histone genes elsewhere remained unaffected. This indicated that the downregulation was specific to HIST1 histone genes. We found that, after trichostatin A treatment, HIST1 histone genes were derepressed, and DNA methylation at their promoters was decreased to the level of in vitro fertilization embryos. Therefore, our results indicate that the reduced expression of HIST1 histone genes is a consequence of poor epigenetic reprogramming in SCNT blastocysts.
authors.affiliation: Development and Differentiation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, South Korea Department of Functional Genomics, University of Science and Technology, Daejeon, 305-350, South Korea.
authors.forename: Byungkuk
authors.identifier: 0000-0002-5419-6964
authors.initials: B
authors.lastname: Min
authors.affiliation: Development and Differentiation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, South Korea.
authors.forename: Sunwha
authors.initials: S
authors.lastname: Cho
authors.affiliation: Development and Differentiation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, South Korea.
authors.forename: Jung Sun
authors.initials: JS
authors.lastname: Park
authors.affiliation: Development and Differentiation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, South Korea Department of Functional Genomics, University of Science and Technology, Daejeon, 305-350, South Korea.
authors.forename: Kyuheum
authors.initials: K
authors.lastname: Jeon
authors.affiliation: Development and Differentiation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, South Korea Department of Functional Genomics, University of Science and Technology, Daejeon, 305-350, South Korea ykkang@kribb.re.kr.
authors.forename: Yong-Kook
authors.initials: YK
authors.lastname: Kang
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism; D002417:Cattle; D065150:Cellular Reprogramming / Q000235:genetics*; D000067470:Cellular Reprogramming Techniques; D019976:Cloning, Organism; D016000:Cluster Analysis; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005307:Fertilization in Vitro; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D056426:Genetic Loci; D006657:Histones / Q000235:genetics*; D009865:Oocytes / Q000378:metabolism
chemical_list: D006657:Histones
keywords: DNA methylation; HDAC inhibitor; HIST1 cluster; RNA-seq; SCNT; epigenetics; reprogramming