2NBX

Solution structure of the J-K region of EMCV IRES

Summary for 2NBX

• Entry DOI: 10.2210/pdb2nbx/pdb
• Related: 2NBY 2NBZ 2NC0 2NC1
• NMR Information: BMRB: 25996
• Descriptor: IRES RNA (108-MER) (1 entity in total)
• Functional Keywords: ires, translation initiation, viral rna, rna
• Biological source: synthetic construct
• Total number of polymer chains: 1
• Total formula weight: 34838.61

Authors

Imai, S.,D'Souza, V.,Wagner, G. (deposition date: 2016-03-16, release date: 2016-08-10, Last modification date: 2024-05-15)

Primary citation

Imai, S.,Kumar, P.,Hellen, C.U.,D'Souza, V.M.,Wagner, G.
An accurately preorganized IRES RNA structure enables eIF4G capture for initiation of viral translation.
Nat. Struct. Mol. Biol., 23:859-864, 2016

PubMed Abstract: Many viruses bypass canonical cap-dependent translation in host cells by using internal ribosomal entry sites (IRESs) in their transcripts; IRESs hijack initiation factors for the assembly of initiation complexes. However, it is currently unknown how IRES RNAs recognize initiation factors that have no endogenous RNA binding partners; in a prominent example, the IRES of encephalomyocarditis virus (EMCV) interacts with the HEAT-1 domain of eukaryotic initiation factor 4G (eIF4G). Here we report the solution structure of the J-K region of this IRES and show that its stems are precisely organized to position protein-recognition bulges. This multisite interaction mechanism operates on an all-or-nothing principle in which all domains are required. This preorganization is accomplished by an 'adjuster module': a pentaloop motif that acts as a dual-sided docking station for base-pair receptors. Because subtle changes in the orientation abrogate protein capture, our study highlights how a viral RNA acquires affinity for a target protein.

PubMed: 27525590
DOI: 10.1038/nsmb.3280

Experimental method

SOLUTION NMR