TY - JOUR T1 - Identification of regulators of the three-dimensional polycomb organization by a microscopy-based genome-wide RNAi screen. JF - Mol Cell Y1 - 2014 A1 - Gonzalez, Inma A1 - Mateos-Langerak, Julio A1 - Thomas, Aubin A1 - Cheutin, Thierry A1 - Cavalli, Giacomo KW - Animals KW - Cell Line KW - Cell Nucleus KW - Chromatin KW - Cluster Analysis KW - drosophila melanogaster KW - Drosophila Proteins KW - Gene Knockdown Techniques KW - Gene Ontology KW - Imaginal Discs KW - Phenotype KW - Polycomb-Group Proteins KW - Protein Binding KW - Protein Transport KW - RNA Interference KW - Sumoylation AB -

Polycomb group (PcG) proteins dynamically define cellular identities through epigenetic repression of key developmental genes. PcG target gene repression can be stabilized through the interaction in the nucleus at PcG foci. Here, we report the results of a high-resolution microscopy genome-wide RNAi screen that identifies 129 genes that regulate the nuclear organization of Pc foci. Candidate genes include PcG components and chromatin factors, as well as many protein-modifying enzymes, including components of the SUMOylation pathway. In the absence of SUMO, Pc foci coagulate into larger aggregates. Conversely, loss of function of the SUMO peptidase Velo disperses Pc foci. Moreover, SUMO and Velo colocalize with PcG proteins at PREs, and Pc SUMOylation affects its chromatin targeting, suggesting that the dynamic regulation of Pc SUMOylation regulates PcG-mediated silencing by modulating the kinetics of Pc binding to chromatin as well as its ability to form Polycomb foci.

VL - 54 IS - 3 U1 - http://www.ncbi.nlm.nih.gov/pubmed/24703951?dopt=Abstract ER -