Faster, not stronger: How a protein regulates gene expression
Inside the cell, DNA is tightly coiled and packed with several proteins into a structure called "chromatin", which allows DNA to fit in the cell while also preventing genes from being expressed at the wrong time. Guided by a chemical "barcode", specialized effector proteins can bind chromatin and either unwind it or compact further to activate or silence genes. This system has enormous implications for biology and medicine, e.g. cancer research. However, the efficiency of effector-chromatin interactions have been elusive, especially given the weak binding between the two. Tracking these interactions one molecule at a time, EPFL scientists have shown for the first time how a major effector protein speeds up its search for chromatin binding sites pairing up with others of its kind. The elegant molecular mechanism is published in Nature Communications.