Abstract :
DNA ligase catalyzes a strand-joining reaction at a nick junction formed by the annealing of two DNA strands on a DNA template. The requirement of base-pair complementarity at the nick junction has been explored to develop ligase-based technologies for the detection of sequence variance. Analogous to the polymerase chain reaction (PCR), amplification can be achieved through repeated cycles of template denaturation, probe annealing and ligation. When joined by DNA ligase, the two juxtaposed strands might also serve as a template for amplification by PCR or other means. This article reviews progress made over recent years in the development of ligase-based technologies. Several ligase-based techniques have been developed for the high-throughput detection of DNA, homogeneous assays, single-molecular detection, and scanning of unknown mutations. Ligase-based techniques can also be used to detect sequence variance in RNA. Linking DNA-based aptamers to ligation primers – a technique called proximity ligation – also enables ligase-based techniques to be used in the detection of protein molecules.
