Direct evidence for intracellular anterograde co-transport of M-PMV Gag and Env on microtubules

• Authors: Lara E. Pereira, Emory Vaccine Center; Jasmine Clark, Emory University; Petra Grznarova, Institute of Chemical Technology; Xiaoyun Wen, Emory University; Rachel LaCasse, National Institute of Allergy and Infectious Diseases; Tomas Ruml, Institute of Chemical Technology; Paul Spearman, Emory University; Eric Hunter, Emory University
• Journal Title: Virologica Sinica
• Volume: Volume 449
• Publisher: Springer Verlag (Germany) | 2014-01-20, Pages 109-119
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.virol.2013.11.006
• Subjects: Health Sciences, Medicine and Surgery; Health Sciences, Pathology; Biology, Virology
• Keywords: Science & Technology; Life Sciences & Biomedicine; Virology; M-PMV; Envelope; Gag; Anterograde transport; Cytoskeleton; Live cell-imaging; PFIZER MONKEY VIRUS; PERICENTRIOLAR RECYCLING ENDOSOME; TARGETING-RETENTION SIGNAL; MATRIX PROTEIN; D RETROVIRUSES; IN-VITRO; TRANSPORT; POLYPROTEIN; TRAFFICKING; MEMBRANE

Abstract

The intracellular transport of Mason-Pfizer monkey virus (M-PMV) assembled capsids from the pericentriolar region to the plasma membrane (PM) requires trafficking of envelope glycoprotein (Env) to the assembly site via the recycling endosome. However, it is unclear if Env-containing vesicles play a direct role in trafficking capsids to the PM. Using live cell microscopy, we demonstrate, for the first time, anterograde co-transport of Gag and Env. Nocodazole disruption of microtubules had differential effects on Gag and Env trafficking, with pulse-chase assays showing a delayed release of Env-deficient virions. Particle tracking demonstrated an initial loss of linear movement of GFP-tagged capsids and mCherry-tagged Env, followed by renewed movement of Gag but not Env at 4. h post-treatment. Thus, while delayed capsid trafficking can occur in the absence of microtubules, efficient anterograde transport of capsids appears to be mediated by microtubule-associated Env-containing vesicles.