Periodic Report Summary - PREMORRIT (The Polycomb Repression Complex 2 (PRC2): Mechanisms of recruitment and role in tumorigenesis)
A key challenge to development of multicellular organism is to establish and maintain various cell identities among cells sharing a common genome. Cell identities rely therefore on epigenetic regulation. We are focusing our research on the Polycomb group (PcG) of proteins. These proteins are pivotal for the specification and maintenance of cell identity by preventing inappropriate gene activation. They function mostly through the regulation of chromatin structure and, in particular, the post-translational modification of histones. Most of the polycomb proteins have been shown to be part of multiprotein complexes that act in concert to maintain gene repression. Yet considering that each cell type has a defined profile of gene expression, the genes whose transcription should be kept silent varies from one cell to another. How is this cell specific recruitment of the polycomb machinery achieved is the first aim of this proposal. It is known that some components of the polycomb machinery are altered in diseases such as cancer. Whether and how those alterations contribute to cancer progression is the second aims of this proposal.