Structural perspective on the activation of RNAse P RNA by protein.

Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, USA.
Nature Structural & Molecular Biology (Impact Factor: 11.63). 12/2005; 12(11):958-64. DOI: 10.1038/nsmb1004
Source: PubMed

ABSTRACT Ribonucleoprotein particles are central to numerous cellular pathways, but their study in vitro is often complicated by heterogeneity and aggregation. We describe a new technique to characterize these complexes trapped as homogeneous species in a nondenaturing gel. Using this technique, in conjunction with phosphorothioate footprinting analysis, we identify the protein-binding site and RNA folding states of ribonuclease P (RNase P), an RNA-based enzyme that, in vivo, requires a protein cofactor to catalyze the 5' maturation of precursor transfer RNA (pre-tRNA). Our results show that the protein binds to a patch of conserved RNA structure adjacent to the active site and influences the conformation of the RNA near the tRNA-binding site. The data are consistent with a role of the protein in substrate recognition and support a new model of the holoenzyme that is based on a recently solved crystal structure of RNase P RNA.

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