SNAP annotations: PDB entry 1e8o

PDB-id

1e8o; DSSR-derived features in text and JSON formats; DNAproDB

Class

alu ribonucleoprotein particle

Method

X-ray (3.2 Å)

Summary

Core of the alu domain of the mammalian srp

Reference

Weichenrieder O, Wild K, Strub K, Cusack S (2000): "Structure and Assembly of the Alu Domain of the Mammalian Signal Recognition Particle." Nature, 408, 167. doi: 10.1038/35041507.

Abstract

The Alu domain of the mammalian signal recognition particle (SRP) comprises the heterodimer of proteins SRP9 and SRP14 bound to the 5' and 3' terminal sequences of SRP RNA. It retards the ribosomal elongation of signal-peptide-containing proteins before their engagement with the translocation machinery in the endoplasmic reticulum. Here we report two crystal structures of the heterodimer SRP9/14 bound either to the 5' domain or to a construct containing both 5' and 3' domains. We present a model of the complete Alu domain that is consistent with extensive biochemical data. SRP9/14 binds strongly to the conserved core of the 5' domain, which forms a U-turn connecting two helical stacks. Reversible docking of the more weakly bound 3' domain might be functionally important in the mechanism of translational regulation. The Alu domain structure is probably conserved in other cytoplasmic ribonucleoprotein particles and retroposition intermediates containing SRP9/14-bound RNAs transcribed from Alu repeats or related elements in genomic DNA.