8SH5

Crystal structure of 3'cap-independent translation enhancers (CITE) from Pea enation mosaic virus RNA 2 (PEMV2) with Fab BL3-6K170A

Summary for 8SH5

• Entry DOI: 10.2210/pdb8sh5/pdb
• Descriptor: Fab BL3-6K170A heavy chain, Fab BL3-6K170A light chain, RNA (88-MER), ... (4 entities in total)
• Functional Keywords: cite, pemv2, pte, rna, rna-immune system complex, rna/immune system
• Biological source: Mus musculus (mouse); More
• Total number of polymer chains: 3
• Total formula weight: 75963.64

Authors

Lewicka, A.,Roman, C.,Rice, P.A.,Piccirilli, J.A. (deposition date: 2023-04-13, release date: 2023-08-16, Last modification date: 2024-11-13)

Primary citation

Lewicka, A.,Roman, C.,Jones, S.,Disare, M.,Rice, P.A.,Piccirilli, J.A.
Crystal structure of a cap-independent translation enhancer RNA.
Nucleic Acids Res., 51:8891-8907, 2023

PubMed Abstract: In eukaryotic messenger RNAs, the 5' cap structure binds to the translation initiation factor 4E to facilitate early stages of translation. Although many plant viruses lack the 5' cap structure, some contain cap-independent translation elements (CITEs) in their 3' untranslated region. The PTE (Panicum mosaic virus translation element) class of CITEs contains a G-rich asymmetric bulge and a C-rich helical junction that were proposed to interact via formation of a pseudoknot. SHAPE analysis of PTE homologs reveals a highly reactive guanosine residue within the G-rich region proposed to mediate eukaryotic initiation factor 4E (eIF4E) recognition. Here we have obtained the crystal structure of the PTE from Pea enation mosaic virus 2 (PEMV2) RNA in complex with our structural chaperone, Fab BL3-6. The structure reveals that the G-rich and C-rich regions interact through a complex network of interactions distinct from those expected for a pseudoknot. The motif, which contains a short parallel duplex, provides a structural mechanism for how the guanosine is extruded from the core stack to enable eIF4E recognition. Homologous PTE elements harbor a G-rich bulge and a three-way junction and exhibit covariation at crucial positions, suggesting that the PEMV2 tertiary architecture is conserved among these homologs.

PubMed: 37548413
DOI: 10.1093/nar/gkad649

Experimental method

X-RAY DIFFRACTION (2.75 Å)