FIG. 2.

Mitochondrial morphology is modulated by mitochondrial fusion and fission proteins in β-cells. A: In primary β-cells, overexpression of the fusion protein OPA1 leads to mitochondrial fragmentation. Overexpression was achieved by adenoviral transduction of GFP or OPA1 at equal concentrations of viral particles. B: Level of OPA1 overexpression in INS1 cells was controlled by the dose of viral particles used. Mild overexpression causes mitochondria to take on a dense and elaborate morphology compared with controls. Further increases in OPA1 overexpression levels resulted in mitochondrial fragmentation. C: In primary β-cells, overexpression of DN DRP1 to reduce mitochondrial fission leads to mitochondrial swelling. D: In INS1 cells, overexpression of DN DRP1 leads to network superfusion and a limited amount of mitochondrial swelling. The number and concentration of viral particles used in A, C, and D was identical. (A high-quality digital representation of this figure is available in the online issue.)