Bats Possess Unique Variants of the Antiviral Restriction Factor Tetherin

Joshua A. Hayward; Mary Tachedjian; Adam Johnson; Tamsin B. Gordon; Jie Cui; Glenn A. Marsh; Michelle L. Baker; Lin-Fa Wang; Gilda Tachedjian

The basic function of P. alecto and M. macropus tetherins to decrease viral particle release was tested against model HIV-1 virus-like particles (VLPs), which are known to be restricted by tetherin from non-human mammals including cats, sheep, and other bat species (Hypsignathus monstrosus and Epomops buettikoferi) (19, 42, 43) . 293T cells were transfected with bat tetherin constructs in addition to plasmids expressing HIVΔVpu VLPs that do not express Vpu, an antagonist of human tetherin (17) . P. alecto tetherin isoforms A and B restricted the release of HIVΔVpu VLPs, while isoform C did not ( Figure 9A ). M. macropus tetherin A also restricted HIVΔVpu VLP release from 293T cells, however tetherin B was unable to inhibit HIVΔVpu VLP egress ( Figure 9B ). These data indicate that, with the exception of P. alecto tetherin isoform C and M. macropus tetherin B, tagged bat tetherin proteins are functionally capable of restricting the release of HIV-1 particles from mammalian cells in the absence of Vpu.