1LNG

Crystal Structure of the SRP19-7S.S SRP RNA Complex of M. jannaschii

Summary for 1LNG

• Entry DOI: 10.2210/pdb1lng/pdb
• Descriptor: 7S.S SRP RNA, Signal recognition particle 19 kDa protein, MAGNESIUM ION, ... (4 entities in total)
• Functional Keywords: protein-rna complex, signaling protein-rna complex, signaling protein/rna
• Biological source: Methanocaldococcus jannaschii; More
• Total number of polymer chains: 2
• Total formula weight: 41853.76

Authors

Hainzl, T.,Huang, S.,Sauer-Eriksson, A.E. (deposition date: 2002-05-03, release date: 2002-06-07, Last modification date: 2023-08-16)

Primary citation

Hainzl, T.,Huang, S.,Sauer-Eriksson, A.E.
Structure of the SRP19 RNA complex and implications for signal recognition particle assembly.
Nature, 417:767-771, 2002

PubMed Abstract: The signal recognition particle (SRP) is a phylogenetically conserved ribonucleoprotein. It associates with ribosomes to mediate co-translational targeting of membrane and secretory proteins to biological membranes. In mammalian cells, the SRP consists of a 7S RNA and six protein components. The S domain of SRP comprises the 7S.S part of RNA bound to SRP19, SRP54 and the SRP68/72 heterodimer; SRP54 has the main role in recognizing signal sequences of nascent polypeptide chains and docking SRP to its receptor. During assembly of the SRP, binding of SRP19 precedes and promotes the association of SRP54 (refs 4, 5). Here we report the crystal structure at 2.3 A resolution of the complex formed between 7S.S RNA and SRP19 in the archaeon Methanococcus jannaschii. SRP19 bridges the tips of helices 6 and 8 of 7S.S RNA by forming an extensive network of direct protein RNA interactions. Helices 6 and 8 pack side by side; tertiary RNA interactions, which also involve the strictly conserved tetraloop bases, stabilize helix 8 in a conformation competent for SRP54 binding. The structure explains the role of SRP19 and provides a molecular framework for SRP54 binding and SRP assembly in Eukarya and Archaea.

PubMed: 12050674
DOI: 10.1038/nature00768

Experimental method

X-RAY DIFFRACTION (2.3 Å)