FIGURE 9.

The effect of RBEL1 proteins on ERK phosphorylation. A, MCF-7 cells were transiently transfected with empty vector or HA-tagged RBEL1A, -B, -C, and -D expression constructs. 24 h after transfection, cells were harvested and Western blot analysis was performed using phospho-ERK antibodies, pan-ERK, and β-actin antibodies. B, RBEL1 knockdown significantly inhibits ERK phosphorylation. MCF-7 cells were introduced with RBEL1 targeting shRNAs (#59, #60, and #61) as described under “Experimental Procedures.” Four days later, cells were harvested and cell lysates were analyzed by Western blotting using ERK phospho-specific antibodies as well as pan-ERK and β-actin antibodies.