title: Methyl-CpG-Binding Protein 2 Improves the Development of Mouse Somatic Cell Nuclear Transfer Embryos.
abstract: Methyl-CpG-binding domain proteins (MBPs) connect DNA methylation and histone modification, which are the key changes of somatic cell reprogramming. Methyl-CpG-binding protein 2 (MeCP2) was the first discovered MBP that has been extensively studied in the neurodevelopmental disorder Rett syndrome. However, a role for MeCP2 during cellular reprogramming associated with somatic cell nuclear transfer (SCNT) has not been examined. In this study, we discovered that MeCP2 expression was significantly lower in embryos generated by SCNT compared with those generated by intracytoplasmic sperm injection (ICSI). We genetically modified mouse embryonic fibroblasts (MEFs) to overexpress MeCP2 and serve as donor cells for nuclear transfer (NT) to investigate the effects of MeCP2 on preimplantation development of SCNT embryos. The blastocyst rate (35.71%) of MeCP2 overexpressed embryos (NT(+)) was significantly greater than in nontransgenic embryos (NT(-), 24.29%). Furthermore, immunofluorescence experiments revealed that 5-methylcytosine (5mC) was transferred to 5-hydroxymethylcytosine (5hmC) to a greater extent in NT(+) embryos than in NT(-) embryos. Real-time PCR evaluation of gene expression also showed that embryonic development-associated genes, such as Oct4 and Nanog, were significantly higher in the NT(+) group compared to the NT(-) group. Collectively, these results suggested that MeCP2 facilitated Tet3 activity, enhanced expression of pluripotency-related genes, and eventually improved the development of NT embryos. Finally, we performed chromatin immunoprecipitation to identify direct targets of MeCP2 and constructed a protein interaction network to elucidate several putative MeCP2 targets.
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Zhen-Dong
authors.initials: ZD
authors.lastname: Wang
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .|2 College of Bioinformatics Science and Technology, Harbin Medical University, Harbin Medical University , Harbin, 150081, China .
authors.forename: Lian
authors.initials: L
authors.lastname: Duan
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Zi-Hui
authors.initials: ZH
authors.lastname: Zhang
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Si-Hang
authors.initials: SH
authors.lastname: Song
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Guang-Yu
authors.initials: GY
authors.lastname: Bai
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Na
authors.initials: N
authors.lastname: Zhang
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Xing-Hui
authors.initials: XH
authors.lastname: Shen
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Jing-Ling
authors.initials: JL
authors.lastname: Shen
authors.affiliation: 1 Department of Histology and Embryology, Harbin Medical University , Harbin, 150081, China .
authors.forename: Lei
authors.initials: L
authors.lastname: Lei
mesh_terms: D000818:Animals; D019976:Cloning, Organism; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D008297:Male; D051783:Methyl-CpG-Binding Protein 2 / Q000096:biosynthesis / Q000235:genetics; D051379:Mice; D000071317:Nanog Homeobox Protein / Q000235:genetics / Q000378:metabolism; D053652:Nuclear Transfer Techniques; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism
chemical_list: C497393:Mecp2 protein, mouse; D051783:Methyl-CpG-Binding Protein 2; D000071317:Nanog Homeobox Protein; C475540:Nanog protein, mouse; D050814:Octamer Transcription Factor-3; C494174:Pou5f1 protein, mouse