Editors' ChoiceImmunology

Keeping Alphaviruses Under Wraps

Science Signaling  18 Feb 2014:
Vol. 7, Issue 313, pp. ec51
DOI: 10.1126/scisignal.2005188

Viruses mutate to avoid detection, and the host responds in kind. For example, 2′-O methylation of the 5′ cap of viral RNA allows viruses to escape detection by the interferon-stimulated host defense protein, IFIT1. Alphaviruses, however, lack this modification but are able to remain undetected in the presence of IFIT1. How? Using a combination of viral mutants and biochemical analysis, Hyde et al. found that alphaviruses contain secondary structural motifs in the 5′ untranslated region of their genomic RNA that allow them to avoid detection by IFIT1. When these regions were rendered nonfunctional, IFIT1 was able to keep the virus under control.

J. L. Hyde, C. L. Gardner, T. Kimura, J. P. White, G. Liu, D. W. Trobaugh, C. Huang, M. Tonelli, S. Paessler, K. Takeda, W. B. Klimstra, G. K. Amarasinghe, M. S. Diamond, A viral RNA structural element alters host recognition of nonself RNA. Science 343, 783–787 (2014). [Abstract] [Full Text]