Viral and cellular determinants of polarized trafficking of viral envelope proteins from insect-specific and insect-vectored viruses in insect midgut and salivary gland cells

Viruses that use insects as hosts must navigate specific routes through different insect tissues to complete their life cycles. The routes may differ substantially depending on the life cycle of the virus. Both insect pathogenic viruses and insect-vectored viruses must navigate through the polarized cells of the midgut epithelium to establish a systemic infection. In addition, insect-vectored viruses must also navigate through the polarized salivary gland epithelium for transmission. Thus, insect-vectored viruses appear to traffic in opposite directions in these two tissues. In this study, we asked whether two viral envelope proteins (VSV G and baculovirus GP64) alone encode the signals necessary for the polarized trafficking associated with their respective life cycles. Using <i>Drosophila</i> as a model to examine tissue-specific polarized trafficking of these viral envelope proteins, we identified one of the virus-encoded signals and several host proteins associated with regulating the polarized trafficking in the midgut epithelium.