Donnerstag, 03. Juli 2014 Hörsaal G (I1), 17:00 Uhr c.t.

1. Cluster of Excellence - “From Regenerative Biology to Reconstructive Therapy” Guest: Dr. Jeroen KrijgsveldEMBL, Heidelberg „Novel approaches in chromatin-centered proteomics to investigate pluripotency and development“ Donnerstag, 03. Juli 2014 Hörsaal G (I1), 17:00 Uhr c.t. Terminabsprachen für Gespräche mit dem Gast Prof. Büttner, Tel. 01761-532-8277 (MHH intern 17-8277)

2. Cluster of Excellence - “From Regenerative Biology to Reconstructive Therapy” Novel approaches in chromatin-centered proteomics to investigate pluripotency and development Jeroen Krijgsveld European Molecular Biology Laboratory (EMBL), Heidelberg, Germany Arguably, chromatin is among the cell's most important organelles, since it is here that the timing and level of transcription of every single gene in the genome are regulated. To understand the details of these processes, it is imperative to comprehend how proteins associate with chromatin, and how this depends on cellular context. To address this, we have developed two complementary methods for the global identification of proteins that associate with the genome, and for the identification of proteins that bind to DNA in a locus-specific manner. In the global approach we demonstrate that chromatin in stem cells consists of >3000 proteins, the composition of which is highly dynamic depending on pluripotency state. Our data also reveal that proteins from many cellular locations (cytoplasm, membrane, secretory proteins) can associate with chromatin dynamically, underscoring that chromatin factors extend far beyond histones and transcription factors. The second approach entails the development of a novel and unique approach to identify proteins that bind to a specific genomic locus of interest. We have applied this to the promoter region of Nanog, indentifying known proteins involved in transcriptional regulation of this pluripotency gene, as well as many novel candidates. Since this method can be applied to any other genomic region, this will provide a powerful approach for the discovery of proteins conferring functionality to chromatin (transcription regulation, structure, etc).