Fig. 6.

Hydrophobic region of OPA3 in the MOM is sufficient to trigger mitochondrial fragmentation. a Diagram of C-terminally YFP-fused OPA3 deletion mutants; +, fragmented mitochondria; Mito, mitochondria; Cyto, cytoplasm. b HeLa cells were transfected with the indicated constructs and analyzed by confocal microscopy. DsRed-Mito was used as a mitochondrial marker. c The amino acid sequence of OPA3 was analyzed by Kyte-Doolittle hydropathy plot server. The putative membrane-spanning segment is shown as a black rectangle. d, e Cells were co-transfected with the indicated constructs. Mitochondrial morphology was analyzed by confocal microscopy. Data are the mean ± SD of three experiments, each with 100 cells per treatment. f Mitochondrial fractions with OPA3 (Δ83–102)-YFP in control buffer or swelling buffer (OS) were digested by proteinase K (PK). Western blots of the separated proteins were probed with anti-GFP, anti-Tom 20, and anti-OPA1 antibodies