Seminar by Matthieu Gerard, Institut de Biologie et de Technologies de Saclay, FranceAud

Genome-wide mapping of transcription factor-DNA interactions and chromatin epigenetic marks is essential to understand how the expression of the mammalian genome is controlled during normal life and disease.The human and mouse genomes contain about 30 genes encoding ATP-dependent chromatin remodelling factors. These factors, which together constitute theSNF2 family, are involved in the regulation of gene expression by modulating the accessibility and composition of chromatin.It is currently unclear why mammalian cells contain so many different members of the SNF2 family.

 

The aim of our project is to provide a comprehensive view of the role of the chromatin remodelling factor family in the regulation of gene expression in mouse embryonic stem (ES) cells. For this purpose, we performed a genome-wide binding study of chromatin remodelling factors combined with computational analysis, in order to identify the target genes of these factors.

 

This project involved several steps:

(1) TAP tagging of chromatin remodelers. Using homologous recombination in mouse ES cells, we introduced a tandem affinity purification (TAP) tag at the C-terminus of 15 genes encoding chromatin remodelling factors.

(2) Use of the TAP-tag to perform chromatin immunoprecipitation (ChIP) experiments, followed by large scale sequencing of the immunoprecipitated DNA onto a new generation platform.

(3) Computational analysis of the data, in order to identify all chromatin remodeler DNA binding sites onto the ES cell genome. Our analysis allows us to decipher how chromatin remodelling factors contribute to the control of transcriptional networks in ES cells.