Proteins critical for compacting DNA in preparation for cell division actually interact with the double helix to fashion it into a kind of “molecular Velcro,” researchers have discovered. The proteins, called condensins, are important for a variety of housekeeping processes in chromosomes, but the mechanics behind their function have been largely unknown. When the researchers alternately stretched and compressed a single molecule of DNA with condensins attached, they found that the DNA extended in stepwise “clicks,” akin to Velcro unzipping.
