Figure 2.
The long forms of isoform 1 or isoform 2 lack substantial mitochondrial fusion activity. (A) Processing of mRNA splice forms 1 and 2 and their ΔS1 mutants. After expression in OPA1-null cells, Western blot analysis was used to detect OPA1. Actin was used as a loading control. (B) Tubulation of mitochondria in OPA1-null cells. After expression of the indicated splice forms in OPA1-null cells containing mitochondrially targeted DsRed, cells were scored as in Fig. 1 C; error bars indicate the SD from triplicate experiments.