Simultaneous detection of kinase and phosphatase activities of polynucleotide kinase using molecular beacon probes.
Phosphorylation and dephosphorylation of DNA by polynucleotide kinase (PNK) has an important role in DNA damage repair, replication, and recombination. Traditionally, it is assayed by denaturing gel electrophoresis and autoradiography, which are tedious and not sensitive. We report on the development of a sensitive and simple method for PNK assay based on DNA ligation using a molecular beacon. Enzyme activity of PNK is measured down to a limit of 0.002 unit/ml. The method not only provides a universal platform for simultaneous monitoring of kinase and phosphatase activities, but also shows great potential in biological research, drug discovery, and clinical diagnostics.
PubMed Abstracts
PubMed Abstracts