Structural highlights
Function
[NCAP_LASSJ] Encapsidates the genome, protecting it from nucleases. The encapsidated genomic RNA is termed the nucleocapsid (NC). Serves as template for viral transcription and replication. The increased presence of protein N in host cell does not seem to trigger the switch from transcription to replication as observed in other negative strain RNA viruses. Disables the host innate defense by interfering with beta interferon (IFN-beta) production. Strongly inhibits the nuclear translocation of IRF3, a protein involved in IFN activation pathway. Also inhibits the activation of IFN-beta and IRF3-dependent promoters (By similarity).
Publication Abstract from PubMed
Lassa virus, the causative agent of Lassa fever, causes thousands of deaths annually and is a biological threat agent, for which there is no vaccine and limited therapy. The nucleoprotein (NP) of Lassa virus has essential roles in viral RNA synthesis and immune suppression, the molecular mechanisms of which are poorly understood. Here we report the crystal structure of Lassa virus NP at 1.80 A resolution, which reveals amino (N)- and carboxy (C)-terminal domains with structures unlike any of the reported viral NPs. The N domain folds into a novel structure with a deep cavity for binding the m7GpppN cap structure that is required for viral RNA transcription, whereas the C domain contains 3'-5' exoribonuclease activity involved in suppressing interferon induction. To our knowledge this is the first X-ray crystal structure solved for an arenaviral NP, which reveals its unexpected functions and indicates unique mechanisms in cap binding and immune evasion. These findings provide great potential for vaccine and drug development.
Cap binding and immune evasion revealed by Lassa nucleoprotein structure.,Qi X, Lan S, Wang W, Schelde LM, Dong H, Wallat GD, Ly H, Liang Y, Dong C Nature. 2010 Nov 17. PMID:21085117[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Qi X, Lan S, Wang W, Schelde LM, Dong H, Wallat GD, Ly H, Liang Y, Dong C. Cap binding and immune evasion revealed by Lassa nucleoprotein structure. Nature. 2010 Nov 17. PMID:21085117 doi:10.1038/nature09605
