Fig. 2: K25A replication can be rescued by second-site mutations.

A, B MT4 cells were transfected with infectious molecular clones harboring mutations at either R18 (A) or K25 (B) and replication kinetics were assessed by quantifying supernatant RT activity. C Supernatants from (B) and similar repeat experiments were used to infect MT4, C8166, or SupT1 T cell lines to assess replication kinetics after acquisition of compensatory mutations. Infectious molecular clones of N21S (D), T216I (E), G208R (F), A105T (G) and G225S (H) variants were used to transfect MT4 cells to assess replication kinetics.