Selective recognition of a tetra-amino-acid motif containing phosphorylated tyrosine residue by ribonucleopeptide

Abstract

We describe here a ribonucleopeptide (RNP) receptor targeting a tetra-amino-acid motif containing phosphotyrosine, GpYSR. GpYSR-binding RNP receptors were obtained from an RNA-based RNP library by in vitro selection. These receptors have a higher affinity than those of previously obtained pY-binding RNP receptors. One of these RNP receptors exhibited unique specificity to the target GpYSR peptide over other tetra-amino-acid peptides derived from the tyrosine-phosphorylation sites of native proteins. The GpYSR-binding RNP receptor discriminated not only the phosphorylated tyrosine residue, but also its surrounding three amino acid residues. Thus, RNP receptors could target a defined pY-containing amino-acid sequence by expanding the recognition surface within the ligand-binding pocket of RNP.