Summary information and primary citation

PDB-id
4p3e; SNAP-derived features in text and JSON formats; DNAproDB
Class
RNA binding protein-RNA
Method
X-ray (3.5 Å)
Summary
Structure of the human srp s domain
Reference
Grotwinkel JT, Wild K, Segnitz B, Sinning I (2014): "SRP RNA remodeling by SRP68 explains its role in protein translocation." Science, 344, 101-104. doi: 10.1126/science.1249094.
Abstract
The signal recognition particle (SRP) is central to membrane protein targeting; SRP RNA is essential for SRP assembly, elongation arrest, and activation of SRP guanosine triphosphatases. In eukaryotes, SRP function relies on the SRP68-SRP72 heterodimer. We present the crystal structures of the RNA-binding domain of SRP68 (SRP68-RBD) alone and in complex with SRP RNA and SRP19. SRP68-RBD is a tetratricopeptide-like module that binds to a RNA three-way junction, bends the RNA, and inserts an α-helical arginine-rich motif (ARM) into the major groove. The ARM opens the conserved 5f RNA loop, which in ribosome-bound SRP establishes a contact to ribosomal RNA. Our data provide the structural basis for eukaryote-specific, SRP68-driven RNA remodeling required for protein translocation.

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

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