Fig 1.

Characterization of recombinant VSVs encoding the CHIKV E3-E2-6K-E1 polyprotein. (A) Diagram of rVSV genomes with the insertion of CHIKV envelope polyprotein in full-length VSV and VSVΔG vectors. The gene order is shown in the 3′-to-5′ direction on the negative-sense RNA genome. (B) Expression of CHIKV envelope proteins detected by indirect immunofluorescence microscopy using anti-VSV G MAb or anti-CHIKV mouse serum in infected (as indicated) BHK-21 cells. Photomicrographs show cell nuclei stained with DAPI in all fields. (C) [³⁵S]methionine-labeled crude cell lysates of infected BHK-21 cells analyzed by SDS-PAGE showing VSV proteins and CHIKV envelope proteins. VSV proteins are indicated to the left, and CHIKV envelope proteins and molecular masses of VSV proteins are indicated to the right. (D) [³⁵S]methionine-labeled and purified virions analyzed by SDS-PAGE. Proteins incorporated into the virions are indicated.