Chromatin is a structure in the cell nucleus that helps pack DNA tightly by wrapping it around proteins called histones. These DNA-protein units, called nucleosomes, control how genes are turned on or off by allowing or blocking DNA access to factors that regulate gene activity. Large protein complexes called chromatin remodelers help move nucleosomes to make DNA accessible to these factors. Now, FMI researchers found that a component of a specific family of chromatin remodelers is important for placing nucleosomes in the right spots to keep certain areas of the DNA open.