Construction of a stable functional ribonucleopeptide complex by the covalent linking method.

We describe here a novel strategy to create a stable functional ribonucleopeptide (RNP) complex by the covalent linking method. Adenosine-5'-triphosphate (ATP)-binding RNP receptors were selected from the RNP library by in vitro selection. The RNA subunit of RNP is utilized to construct a ligand-binding cavity, while the peptide subunit can be functionalized independently. By introducing a fluorophore at the N-terminus of the Rev peptide subunit, the ATP-binding RNP receptor is successfully converted to a noncovalent complex of ATP-responsive fluorescent RNP sensor. Such a noncovalent RNP sensor could be covalently linked by the tethering the RNA to the fluorophore-labeled peptide subunit to form a stable RNP sensor without losing the original function.