Photochemical regulation of DNAzyme activity using reversibleDNA photo-cross-linking

摘要

Enzymes are used in genetic engineering as a tool to ligate and cleave nucleic acids.However,because enzymes are composed of proteins,they require optimum pH,temperature,and buffer conditions.Therefore,a DNAzyme that can edit both nucleic acids and enzymes hasbeen developed by in vitro selection.Compared with the reaction conditions for enzymes,thosefor DNAzymes are more moderate,with the pH,temperature,and salt conditions beingespecially less restrictive.Moreover,DNAzymes can be easily artificially modified.Becauseof these advantages,their applications as biosensors and in DNA nanotechnology are expected.Since DNAzymes are always in an activity ON state,the proper regulation of their activity atany place and time is needed for their application.Several methods for regulating DNAzymeactivity have been reported,with those that modify the secondary structure using DNA probesbeing the most studied.This DNA probe method is dependent on a thermoreversible reaction,and the control leak in the active OFF state is a problem.Regulatory methods using disulfidebonds or metal ions have also been reported,but these have many problems as well,such asthe inability to completely regulate the DNAzyme activity and complicated activationswitching.