Table 1.
Summary of mitochondrial morphologies observed in COS-7 cells transfected with mutant Drp1
| n | Weak
|
Strong
|
Average phenotype | |||
|---|---|---|---|---|---|---|
| Wild type | Loose net | Collapsed | Degenerate | |||
| WT | 103 | 100 | 0 | 0 | 0 | None |
| K38A | 203 | 0 | 18 | 64 | 18 | Strong |
| V41F at 30°C | 96 | 2 | 33 | 60 | 5 | Intermediate |
| V41F at 40°C | 108 | 0 | 8 | 44 | 48 | Strong |
| T59A | 112 | 0 | 12 | 61 | 27 | Strong |
| G281D at 30°C | 107 | 40 | 48 | 11 | 1 | Weak |
| G281D at 40°C | 120 | 6 | 13 | 46 | 35 | Strong |
The transfected cells were treated with nocodazole to disperse the perinuclear mitochondrial clusters. The phenotypes of individual cells were classified as described in the text and Figure 1. The number of cells that were counted is shown (n) followed by the percentage of cells in each phenotypic class. Staining with anti-Drp1 antibody showed that the overexpressed protein was mostly cytosolic with wild-type Drp1, aggregated with Drp1(K38A), cytosolic with Drp1(V41F) at both temperatures, sometimes aggregated with Drp1(T59A), cytosolic Drp1(G281D) at 30°C, and sometimes aggregated with Drp1(G281D) at 40°C.