SNAP output for PDB entry 2xxa [SNAP web server]

PDB-id

2xxa; SNAP-derived features in text and JSON formats; DNAproDB

Class

protein transport

Method

X-ray (3.94 Å)

Summary

The crystal structure of the signal recognition particle (srp) in complex with its receptor(sr)

Reference

Ataide SF, Schmitz N, Shen K, Ke A, Shan S, Doudna JA, Ban N (2011): "The Crystal Structure of the Signal Recognition Particle in Complex with its Receptor." Science, 331, 881. doi: 10.1126/SCIENCE.1196473.

Abstract

Cotranslational targeting of membrane and secretory proteins is mediated by the universally conserved signal recognition particle (SRP). Together with its receptor (SR), SRP mediates the guanine triphosphate (GTP)-dependent delivery of translating ribosomes bearing signal sequences to translocons on the target membrane. Here, we present the crystal structure of the SRP:SR complex at 3.9 angstrom resolution and biochemical data revealing that the activated SRP:SR guanine triphosphatase (GTPase) complex binds the distal end of the SRP hairpin RNA where GTP hydrolysis is stimulated. Combined with previous findings, these results suggest that the SRP:SR GTPase complex initially assembles at the tetraloop end of the SRP RNA and then relocalizes to the opposite end of the RNA. This rearrangement provides a mechanism for coupling GTP hydrolysis to the handover of cargo to the translocon.