Nef Activates Rac in Resting CD4⁺ T Lymphocytes

<div><p>(A) HIV-1 Nef activates Rac in Jurkat T cells. Jurkat T cells (lane 1) were transduced with a control empty vector (FUGW; lane 2) or the same vector expressing HIV-1 NA7 Nef (FUGWCNA7; lane 3). Rac_GTP was precipitated from cell extracts with recombinant PAK1 PBD–GST. PBD–GST bound Rac_GTP (top), total Rac present in extracts (middle), and Nef (bottom) were detected by immunoblotting.</p> <p>(B) Flow cytometric analysis of Gag and CD4 expression in resting CD4⁺ T lymphocytes transduced with HIV-1 derived vectors in the presence of IL-7. Percentages of cells productively infected with <i>nef</i>-deleted H-Δ vector (boxed area in middle panel) or with HIV-1 NA7 <i>nef</i> containing H-NA7 vector (right panel) are shown. Results obtained with uninfected control CD4⁺ T cells cultured in the presence of IL-7 are also shown (left panel).</p> <p>(C) HIV-1 Nef specifically activates Rac in resting primary CD4⁺ T lymphocytes. Rac_GTP and CDC42_GTP were precipitated with PAK1 PBD–GST from extracts prepared from CD4⁺ T lymphocytes transduced with HIV-1 derived vectors, shown in (B), and analyzed as described in (A).</p>