Role and Regulation of DNA Methylation in Cellular Reprogramming

• Applicant: Professor Dr. Heinrich Leonhardt
• Subject Area: Cell Biology ; Biochemistry
• Term: from 2008 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 66270595

• Final Report Year: 2014

Final Report Abstract

We could show that global DNA hypomethylation prevents consolidation of differentiation programs and allows reversion to the embryonic stem cell state. We developed a novel recombinant transcription (designer TALE) to specifically activate the oct4 pluripotency gene and demonstrated targeted transcriptional activation of silent oct4 pluripotency gene by combining designer TALEs and inhibition of epigenetic modifiers. We developed two new methods to quantify and map this new DNA base (5 hydroxymethylcytosine, 5hmC) in pluripotency and differentiation. We could show that the new DNA base 5hmC is recognized by the multi-domain protein Uhrf1, which is essential for the maintenance of DNA methylation in stem cells. In summary, we developed novel tools to study DNA modifications that are now widely used in the scientific community and contributed to a better understanding of the role of DNA modifications during development, differentiation and reprogramming.

Publications

• (2010). Differentiation and large scale spatial organization of the genome. Curr Opin Genet Dev. 20, 562-569
  Joffe, Boris; Leonhardt, Heinrich & Solovei, Irina
  
• (2010). Sensitive enzymatic quantification of 5-hydroxymethylcytosine in genomic DNA. Nucl. Acids Res. 38, e181
  Szwagierczak, Aleksandra; Bultmann, Sebastian; Schmidt, Christine S.; Spada, Fabio & Leonhardt, Heinrich
  
• (2011). Characterization of PvuRts1I endonuclease as a tool to investigate genomic 5 hydroxymethylcytosine. Nucl. Acids Res. 39, 5149-56
  Szwagierczak, Aleksandra; Brachmann, Andreas; Schmidt, Christine S.; Bultmann, Sebastian; Leonhardt, Heinrich & Spada, Fabio
  
• (2011). Generation and characterization of rat and mouse monoclonal antibodies specific for MeCP2 and their use in X-inactivation studies. PLoS ONE 6: e26499
  Jost, K. Laurence; Rottach, Andrea; Milden, Manuela; Bertulat, Bianca; Becker, Annette; Wolf, Patricia; Sandoval, Juan; Petazzi, Paolo; Huertas, Dori; Esteller, Manel; Kremmer, Elisabeth; Leonhardt, Heinrich & Cardoso, M. Cristina
  
• (2011). Recognition of 5-hydroxymethylcytosine by the Uhrf1 SRA domain. PLoS ONE 6: e21306
  Frauer, Carina; Hoffmann, Thomas; Bultmann, Sebastian; Casa, Valentina; Cardoso, M. Cristina; Antes, Iris & Leonhardt, Heinrich
  
• (2012). Global DNA Hypomethylation Prevents Consolidation of Differentiation Programs and Allows Reversion to the Embryonic Stem Cell State. PLoS One 2012 Dez, 7, e52629
  Schmidt, Christine S.; Bultmann, Sebastian; Meilinger, Daniela; Zacher, Benedikt; Tresch, Achim; Maier, Kerstin C.; Peter, Christian; Martin, Dietmar E.; Leonhardt, Heinrich & Spada, Fabio
  
• (2012). Targeted transcriptional activation of silent oct4 pluripotency gene by combining designer TALEs and inhibition of epigenetic modifiers. Nucleic Acids Res 40, 5368-77
  Bultmann, Sebastian; Morbitzer, Robert; Schmidt, Christine S.; Thanisch, Katharina; Spada, Fabio; Elsaesser, Janett; Lahaye, Thomas & Leonhardt, Heinrich