Figure 1.

Induction of LFA-1–mediated cellular aggregation by M-Ras[Q71L]. (A) Expression of endogenous RA-GEF-2, but not M-Ras. Protein extracts from BAF/hLFA-1 and BAF/hLFA-1/M-Ras[Q71L] cells were used for immunoblotting to detect endogenous RA-GEF-2 by anti-RA-GEF-2 antibody. Anti-M-Ras and anti-6×His antibodies were used to detect total M-Ras and M-Ras[Q71L], respectively. Anti-actin antibody was used to detect actin as an internal control. (B) M-Ras[Q71L]-induced cellular aggregation. BAF/hLFA-1 cells transfected with or without M-Ras[Q71L] were observed by microscopy. Anti-human LFA-1 antibody (MEM-25) was added to the culture medium to examine the involvement of LFA-1 in the cellular aggregation. The result is representative of more than 10 independent clones, which gave equivalent results. Each bar, 100 μm.