Summary information and primary citation

PDB-id
7uo0; SNAP-derived features in text and JSON formats; DNAproDB
Class
hydrolase-RNA
Method
cryo-EM (3.4 Å)
Summary
E.coli rnasep holoenzyme with mg2+
Reference
Zhu J, Huang W, Zhao J, Huynh L, Taylor DJ, Harris ME (2022): "Structural and mechanistic basis for recognition of alternative tRNA precursor substrates by bacterial ribonuclease P." Nat Commun, 13, 5120. doi: 10.1038/s41467-022-32843-7.
Abstract
Binding of precursor tRNAs (ptRNAs) by bacterial ribonuclease P (RNase P) involves an encounter complex (ES) that isomerizes to a catalytic conformation (ES*). However, the structures of intermediates and the conformational changes that occur during binding are poorly understood. Here, we show that pairing between the 5' leader and 3'RCCA extending the acceptor stem of ptRNA inhibits ES* formation. Cryo-electron microscopy single particle analysis reveals a dynamic enzyme that becomes ordered upon formation of ES* in which extended acceptor stem pairing is unwound. Comparisons of structures with alternative ptRNAs reveals that once unwinding is completed RNase P primarily uses stacking interactions and shape complementarity to accommodate alternative sequences at its cleavage site. Our study reveals active site interactions and conformational changes that drive molecular recognition by RNase P and lays the foundation for understanding how binding interactions are linked to helix unwinding and catalysis.

Cartoon-block schematics in six views (download the tarball)

PyMOL session file Download PDB file View in 3Dmol.js