Host factor Rab11a is critical for efficient assembly of influenza A virus genomic segments

• Type of Material: Article
• Authors: Julianna Han, University of Chicago; Ketaki Ganti, Emory Univ Sch Med; Veeresh K Sali, University of Iowa; Carly Twigg, University of Iowa; Yifeng Zhang, University of Iowa; Senthamizharasi Manivasagam, University of Iowa; Chieh-Yu Liang, University of Iowa; Olivia A Vogel, University of Iowa; Iris Huang, University of Chicago; Shanan N Emmanuel, University of Chicago; Jesse Plung, University of Chicago; Lillianna Radoshevich, University of Iowa; Jasmine T Perez, University of Chicago; Anice Lowen, Emory University; Balaji Manicassamy, University of Iowa
• Language: English
• Date: 2021-05-01
• Publisher: PUBLIC LIBRARY SCIENCE
• Publication Version: Final Published Version
• Copyright Statement: © 2021 Han et al
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1371/journal.ppat.1009517
• Title of Journal or Parent Work: PLOS PATHOGENS
• Volume: 17
• Issue: 5
• Start Page: e1009517
• End Page: e1009517
• Grant/Funding Information: JH and OV were partly supported by the NIH Molecular and Cellular Biology training program at The University of Chicago (T32GM007183) and the NIH Diversity Supplement (R01AI123359- 02S1). AL is supported by NIAID grant R01AI125268 and CEIRS contract HHSN272201400004C. BM is supported by NIAID grants (R01AI123359 and R01AI127775). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
• Keywords: ENDOPLASMIC-RETICULUM; RIBONUCLEOPROTEIN COMPLEXES; TRANSPORT; Microbiology; Virology; Parasitology; TRAFFICKING; Science & Technology; INFECTION; PROTEIN; VIRAL-RNA; Life Sciences & Biomedicine
• Research Categories: Health Sciences, Immunology; Chemistry, Biochemistry

Abstract

It is well documented that influenza A viruses selectively package 8 distinct viral ribonucleoprotein complexes (vRNPs) into each virion; however, the role of host factors in genome assembly is not completely understood. To evaluate the significance of cellular factors in genome assembly, we generated a reporter virus carrying a tetracysteine tag in the NP gene (NP-Tc virus) and assessed the dynamics of vRNP localization with cellular components by fluorescence microscopy. At early time points, vRNP complexes were preferentially exported to the MTOC; subsequently, vRNPs associated on vesicles positive for cellular factor Rab11a and formed distinct vRNP bundles that trafficked to the plasma membrane on microtubule networks. In Rab11a deficient cells, however, vRNP bundles were smaller in the cytoplasm with less co-localization between different vRNP segments. Furthermore, Rab11a deficiency increased the production of non-infectious particles with higher RNA copy number to PFU ratios, indicative of defects in specific genome assembly. These results indicate that Rab11a+ vesicles serve as hubs for the congregation of vRNP complexes and enable specific genome assembly through vRNP:vRNP interactions, revealing the importance of Rab11a as a critical host factor for influenza A virus genome assembly.