FIG 6.

Summary of the phenotypic effects of the MPER and State 1-stabilizing changes on virus sensitivity to Env ligands or cold exposure. The overall phenotypic effects of MPER changes and State 1-stabilizing changes in Env on virus sensitivity to Env ligands and cold exposure (from Fig. 5 and additional side-by-side experiments comparing the four parental Envs) are summarized here. On a schematic view of the HIV-1 Env trimer, the approximately positioned ligands are colored according to increased sensitivity (green) or increased resistance (red). In each case, the phenotypes of the Env variant following the arrow are compared with those of the Env variant preceding the arrow. For example, the phenotypes of wild-type HIV-1_AD8 Envs without and with MPER changes can be compared in (A and B), respectively. For the depictions of the State 1-stabilized Envs in C, D and E, the data from the Q114E/Q567K and Q114E/Q567K/A582T Envs were used, to avoid potential effects of the other changes in the 2-4 RM6 AE Env unrelated to State-1 stabilization. Examination of (B and D) allows a comparison of the effects of the MPER changes in the context of the wild-type HIV-1_AD8 Env and the State 1-stabilized Envs, respectively. The phenotypes of the wild-type HIV-1_AD8 Env, the HIV-1_AD8 Env with MPER changes, and the State 1-stabilized Envs with MPER changes can be compared between in (A, B and E), respectively.