Abstract
Chromatin remodelling complexes are large multi-subunit ATP-dependent DNA translocases that modify DNA-histone interactions to mobilize or evict nucleosomes at specific genomic loci. The SWI/SNF complex plays an important role in transcriptional regulation in yeast and its human equivalent has recently been shown to be the most frequently mutated chromatin regulator in human cancer – mutations affecting human SWI/SNF subunits were observed in 20% of all tumours. A conserved four-protein core sub-complex is sufficient to remodel nucleosomes in vitro. We will use a combination of cryo-EM, X-ray crystallography and single-molecule fluorescence spectroscopy to understand this simplified system at the molecular level.
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