Roles for the recycling endosome, Rab8, and Rab11 in hantavirus release from epithelial cells

Hantavirus structural proteins are believed to localize to intracellular membranes often identified as Golgi membranes, in virus-infected cells. After virus budding into the Golgi luminal space, virus-containing vesicles are transported to the plasma membrane via trafficking pathways that are not well defined. Using the New World hantavirus, Andes virus, we have investigated the role of various Rab proteins in the release of hantavirus particles from infected cells. Rabs 8 and 11 were found to colocalize with Andes virus proteins in virus infected cells and when expressed from cDNA, implicating the recycling endosome as an organelle important for hantavirus infection. Small interfering RNA-mediated downregulation of Rab11a alone or Rab11a and Rab11b together resulted in a decrease in infectious virus particle secretion from infected cells. Downregulation of Rab8a did not alter infectious virus release but reduction of both isoforms did. These data implicate the recycling endosome and the Rab proteins associated with vesicular transport to or from this intracellular organelle as an important pathway for hantavirus trafficking to the plasma membrane.