Interaction of the Tyr-based motifs or full-length TM-CDs of HIV-1, SIV, and HTLV-1 with in vitro-translated μ1 and μ2. μ1 (A, C, and E) and μ2 (B, D, and F) were translated in vitro in rabbit reticulocyte lysate and incubated with identical quantities of GST (lanes 2), GST-HIVΔ (A and B, lanes 3), GST-HIVΔ-Y712A (A and B, lanes 4), GST-SIVΔ (A and B, lanes 5), GST-SIVΔ-Y721A (A and B, lanes 6), GST-HIV (C and D, lanes 3), GST-HIV-Y712A (C and D, lanes 4), GST-SIV (C and D, lanes 5), GST-SIV-Y721A (C and D, lanes 6), GST-HTLV (E and F, lanes 3), GST-HTLV-Y476S (E and F, lanes 4), and GST-HTLV-Y479S (E and F, lanes 5). Bound labeled material was analyzed by SDS-PAGE and autoradiography. One-fifth of the input of μ1 and μ2 in vitro-translated products used for the binding assay was run on lane 1 of each panel.