Organization of the Influenza Virus Replication Machinery

National Resource for Automated Molecular Microscopy, Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
Science (Impact Factor: 33.61). 11/2012; 338(6114). DOI: 10.1126/science.1227270
Source: PubMed


Influenza virus ribonucleoprotein complexes (RNPs) are central to the viral life cycle and in adaptation to new host species. RNPs are composed of the viral genome, viral polymerase, and many copies of the viral nucleoprotein. In vitro cell expression of all RNP protein components with four of the eight influenza virus gene segments enabled structural determination of native influenza virus RNPs by cryo-EM. The cryo-EM structure reveals the architecture and organization of the native RNP, thereby defining the attributes of its largely helical structure and how polymerase interacts with NP and the viral genome. Observations of branched-RNP structures in negative stain EM and their putative identification as replication intermediates suggest a mechanism for viral replication by a second polymerase on the RNP template.

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    • "Sample dilution was adjusted to achieve a homogeneous separation of particles. Samples were stained as previously described (Moeller et al., 2012) (Tao et al., 2013) using a 2% uranyl formate solution. EM micrographs were acquired using a Tecnai F20 Twin transmission electron microscope operating at 200 kV, using a dose of $45 e À /A ˚ 2 and nominal underfocus ranging from 0.7 mm to 1.7 mm. "
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    Structure 01/2015; 23(3). DOI:10.1016/j.str.2014.12.013 · 5.62 Impact Factor
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    • "Mechanistically, RIG-I was found to counteract the accessibility of HBV P protein to the 5 0 -ε stem-loop of pgRNA, which is an important process for the initiation of viral replication (Bartenschlager and Schaller, 1992). As is the case with this, several viral PAMPs known to be recognized by RIG-I, for example, the poly-U/UC tract in the 3 0 nontranslated region of HCV genome (Saito et al., 2008) and 5 0 terminal region of influenza virus genome (Baum et al., 2010) were previously reported to be directly or indirectly critical for viral replication (You and Rice, 2008; Huang et al., 2005; Moeller et al., 2012). In this respect, one could envisage that such an exquisite targeting by RIG-I would confer a unique machinery to ensure efficient antiviral activities of RIG-I. "
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    Immunity 12/2014; DOI:10.1016/j.immuni.2014.12.016 · 21.56 Impact Factor
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    • "The structure of the RNP complex were investigated using cryogenic electron microscopy [4,5], however, there have been no structural analyses of the entire RNP complex or the RNA polymerase complex at the atomic level. Partial domain structures of the RNA polymerase subunit have been reported [6-11]. "
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    PLoS ONE 11/2013; 8(11):e82020. DOI:10.1371/journal.pone.0082020 · 3.23 Impact Factor
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