Microtubule-Dependent Plus- And Minus End-Directed Motilities Are Competing Processes for Nuclear Targeting of Adenovirus

• Published in: The Journal of cell biology Vol. 144; no. 4; pp. 657 - 672
• Main Authors: Suomalainen, Maarit, Nakano, Michel Y., Keller, Stephan, Boucke, Karin, Stidwill, Robert P., Greber, Urs F.
• Format: Journal Article
• Language: English
• Published: United States Rockefeller University Press 22.02.1999; The Rockefeller University Press
• Subjects: Adenovirus; Adenoviruses; Adenoviruses, Human - pathogenicity; Adenoviruses, Human - physiology; Animals; Antivirals; Base Sequence; Cell Line; Cell lines; Cell nucleus; Cell Nucleus - virology; Cells; Cercopithecus aethiops; Cytosol - virology; DNA Primers - genetics; Dynactin Complex; Dyneins - physiology; Epithelial cells; Fluorescent Dyes; Green Fluorescent Proteins; HeLa Cells; Humans; Luminescent Proteins - genetics; Microscopy, Fluorescence; Microtubule-Associated Proteins - physiology; Microtubules; Microtubules - drug effects; Microtubules - physiology; Microtubules - virology; Molecular Motor Proteins - physiology; Movement; Nocodazole - pharmacology; Paclitaxel - pharmacology; Regular; Virions; Virus Replication; Viruses; Zoology
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.144.4.657

Adenovirus (Ad) enters target cells by receptor-mediated endocytosis, escapes to the cytosol, and then delivers its DNA genome into the nucleus. Here we analyzed the trafficking of fluorophore-tagged viruses in HeLa and TC7 cells by time-lapse microscopy. Our results show that native or taxol-stabilized microtubules (MTs) support alternating minus- and plus end-directed movements of cytosolic virus with elementary speeds up to 2.6 μm/s. No directed movement was observed in nocodazole-treated cells. Switching between plus- and minus end-directed elementary speeds at frequencies up to 1 Hz was observed in the periphery and near the MT organizing center (MTOC) after recovery from nocodazole treatment. MT-dependent motilities allowed virus accumulation near the MTOC at population speeds of 1-10 μm/min, depending on the cell type. Overexpression of p50/dynamitin, which is known to affect dynein-dependent minus end-directed vesicular transport, significantly reduced the extent and the frequency of minus end-directed migration of cytosolic virus, and increased the frequency, but not the extent of plus end-directed motility. The data imply that a single cytosolic Ad particle engages with two types of MT-dependent motor activities, the minus end-directed cytoplasmic dynein and an unknown plus end-directed activity.