Galectin-3 promotes HIV-1 budding via association with Alix and Gag p6

Abstract

D ow nloaded from 2 Galectin-3 has been reported to regulate the functions of a number of immune cell types. We previously reported that galectin-3 is translocated to immunological synapses in T cells upon T cell receptor engagement, where it associates with ALG-2-interacting protein X (Alix). Alix is known to coordinate with the endosomal sorting complex required for transport (ESCRT) to promote HIV-1 virion release. We hypothesized that galectin-3 plays a role in HIV-1 viral budding. Cotransfection of cells of the Jurkat T line with galectin-3 and HIV-1 plasmids resulted in increased HIV-1 budding, and suppression of galectin-3 expression by RNAi in Hut78 and primary CD4+ T cells led to reduced HIV-1 budding. We used immunofluorescence microscopy to observe the partial colocalization of galectin-3, Alix, and Gag in HIV-1-infected cells. Results from co-immunoprecipitatio