A protein that’s essential to every cell’s ability to turn off unnecessary genes is well known for its key function of compacting genes and its connection to cancer when it undergoes mutation. But until now, scientists weren’t quite sure how the protein gets where it needs to go to keep genes bound up so they aren’t activated.

In a new study, researchers found that this protein, called linker histone H1, initially flits around inside a cell with no clear aim even in the presence of its target: a nucleosome containing spooled-up segments of DNA. H1 binds directly to two DNA strands sticking out from the nucleosome, but struggles to bind to the nucleosome itself until a chaperone protein escorts it there.