"The normal expression of genes is tightly regulated. Modifications on histones or on DNA play a central role in the control of gene expression and errors in their regulation often result in diseases such as cancer. These modifications can recruit proteins that regulate chromatin function. Since chromatin is a large macromolecular assembly, modifications most likely act in a concerted manner. However, it is still unclear how the information encoded in combinatorial modification patterns on the DNA and histones is translated into biological signals.My aim is to understand how combinations of DNA and histone modifications regulate the activity of chromatin. I will employ the tools of chemical biology, biochemistry and proteomics in conjunction with tissue culture models in order to identify proteins that can recognise DNA and histone modification patterns in the context of chromatin.I propose to use native chemical ligations to generate a library of histone proteins that carry combinations of modifications that are known to mark specific genomic loci. These histones will be assembled into chromatin together with methylated DNA in order to mimic functional genetic elements such as heterochromatin, promoters or enhancers. I will use the recombinantly defined chromatin in chromatin modification, chromatin remodelling and SILAC affinity purification assays in order to identify novel factors that recognise combinatorial modifications. The SILAC affinity purifications will be linked to a primary cell cancer model in order to identify factors that regulate central tumour suppressor genes. The identified factors will be further characterised in vivo, in vitro and in structural studies in order to understand their molecular function. These experiments will identify factors that can read epigenetic signatures contained in chromatin modification patterns. These constitute the primary targets for “epigenetic drugs” that intervene at key stages in the development of cancer."