Patent ID: 7662554

Claim:
A method for the detection of a target nucleic acid molecule in a living cell, comprising: a) exposing the target nucleic acid molecule to a first complementation molecule and a second complementation molecule, wherein the first complementation molecule comprises a first polypeptide portion coupled to a first probe portion, wherein the first probe portion binds to a first nucleic acid hybridization-site, and wherein the second complementation molecule comprises a second polypeptide portion coupled to a second probe portion, wherein the second probe portion binds to a second nucleic acid hybridization site, and wherein the first and second probe portions are nucleic acids or nucleic acid analogues, and wherein when the first and second probe portions hybridize to nucleic acid sites that are located in close proximity to each other, then the first and second polypeptide portions of the first and second complementation molecules interact and form an assembled complementation complex; b) allowing the components to react under conditions that permit the formation of an assembled complementation complex; and c) determining if an assembled complementation complex is present by any means which allows detection of the assembled complex but not the individual polypeptide portions; wherein the presence of an assembled complex shows the target nucleic acid in the living cell.