title: Poly(ADP-ribose) polymerase 1 regulates nuclear reprogramming and promotes iPSC generation without c-Myc.
abstract: Poly(ADP-ribose) polymerase 1 (Parp1) catalyzes poly(ADP-ribosylation) (PARylation) and induces replication networks involved in multiple nuclear events. Using mass spectrometry and Western blotting, Parp1 and PARylation activity were intensively detected in induced pluripotent stem cells (iPSCs) and embryonic stem cells, but they were lower in mouse embryonic fibroblasts (MEFs) and differentiated cells. We show that knockdown of Parp1 and pharmacological inhibition of PARylation both reduced the efficiency of iPSC generation induced by Oct4/Sox2/Klf4/c-Myc. Furthermore, Parp1 is able to replace Klf4 or c-Myc to enhance the efficiency of iPSC generation. In addition, mouse iPSCs generated from Oct4/Sox2/Parp1-overexpressing MEFs formed chimeric offspring. Notably, the endogenous Parp1 and PARylation activity was enhanced by overexpression of c-Myc and repressed by c-Myc knockdown. A chromatin immunoprecipitation assay revealed a direct interaction of c-Myc with the Parp1 promoter. PAR-resin pulldown, followed by proteomic analysis, demonstrated high levels of PARylated Chd1L, DNA ligase III, SSrp1, Xrcc-6/Ku70, and Parp2 in pluripotent cells, which decreased during the differentiation process. These data show that the activation of Parp1, partly regulated by endogenous c-Myc, effectively promotes iPSC production and helps to maintain a pluripotent state by posttranslationally modulating protein PARylation.
authors.affiliation: Genomic Center & Cancer Center, Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 112, Taiwan. shchiou@vghtpe.gov.tw
authors.forename: Shih-Hwa
authors.initials: SH
authors.lastname: Chiou
authors.forename: Bo-Hwa
authors.initials: BH
authors.lastname: Jiang
authors.forename: Yung-Luen
authors.initials: YL
authors.lastname: Yu
authors.forename: Shih-Jie
authors.initials: SJ
authors.lastname: Chou
authors.forename: Ping-Hsing
authors.initials: PH
authors.lastname: Tsai
authors.forename: Wei-Chao
authors.initials: WC
authors.lastname: Chang
authors.forename: Liang-Kung
authors.initials: LK
authors.lastname: Chen
authors.forename: Li-Hsin
authors.initials: LH
authors.lastname: Chen
authors.forename: Yueh
authors.initials: Y
authors.lastname: Chien
authors.forename: Guang-Yuh
authors.initials: GY
authors.lastname: Chiou
mesh_terms: D000818:Animals; D034961:Antigens, Nuclear / Q000378:metabolism; D002454:Cell Differentiation; D002478:Cells, Cultured; D065150:Cellular Reprogramming; D002678:Chimera; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D055785:Gene Knockdown Techniques; D016259:Genes, myc; D006609:High Mobility Group Proteins / Q000378:metabolism; D057026:Induced Pluripotent Stem Cells / Q000166:cytology / Q000502:physiology*; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000235:genetics / Q000378:metabolism; D000072200:Ku Autoantigen; D051379:Mice; D008810:Mice, Inbred C57BL; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism*; D000075223:Poly-ADP-Ribose Binding Proteins; D011401:Promoter Regions, Genetic; D055748:SOXB1 Transcription Factors / Q000235:genetics / Q000378:metabolism; D029867:Xenopus Proteins
chemical_list: D034961:Antigens, Nuclear; D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D050814:Octamer Transcription Factor-3; D000075223:Poly-ADP-Ribose Binding Proteins; C494174:Pou5f1 protein, mouse; D055748:SOXB1 Transcription Factors; C527783:Sox2 protein, mouse; D029867:Xenopus Proteins; C070454:Ssrp1 protein, mouse; C499321:Parp1 protein, mouse; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; C000606510:Xrcc6 protein, mouse; D000072200:Ku Autoantigen; D011088:DNA Ligases; D000072481:DNA Ligase ATP; C000618816:DNA ligase III alpha protein, Xenopus; C000618818:Lig3 protein, mouse