Programming DNA-based systems through effective molarity enforced by biomolecular confinement

The fundamental concept of effective molarity is observed in a variety of biological processes such as protein compartmentalization within organelles, membrane localization and signaling paths. To control molecular encountering and promote effective interactions, Nature places biomolecules in specific sites inside the cell in order to generate a high, localized concentration different from the bulk concentration. Inspired by this mechanism, scientists have artificially recreated in the lab the same strategy to actuate and control artificial DNA-based functional systems. Here we discuss how harnessing effective molarity has led to the development of a number of proximity-induced strategies with applications ranging from DNA-templated organic chemistry and catalysis, to biosensing and protein-supported DNA assembly.