Panel A shows protein domain schematics comparing mitochondrial targeting sequences among homologous mitochondrial proteins. Panel B shows heatmap graphs of protein percent identity between mitochondrial apoptosis inducing factor homologs. Panel C shows confocal microscopy images and Pearson correlation graphs of mitochondrial protein colocalization after wounding. Panel D shows confocal microscopy images and Pearson correlation graphs of ATPase inhibitory factor mitochondrial localization after wounding. Panel E shows confocal microscopy images and fluorescence intensity graphs of mitochondrial apoptosis inducing factor colocalization dynamics. Panel F shows confocal microscopy images and fluorescence intensity graphs of truncated mitochondrial apoptosis inducing factor localization patterns. Panel G shows confocal microscopy images and fluorescence intensity graphs of mitochondrial apoptosis inducing factor fragment localization patterns.
cIF1 translocates to damaged mitochondria. (A) Domain architecture of C. elegans MAI-1, MAI-2, and human IF1. (B) Protein percent identity matrix analysis among C. elegans MAI-1, MAI-2, and human IF1. Values represent pairwise percent identity. (C) Representative confocal images of cytosolic MAI-2-GFP fusion protein localization before and after laser wounding. Strains: Phyp-7-TOMM-20::mKate2(zjuSi126);Pcol-19-MAI-2(ΔΜΤS)(17–109 aa)::GFP(zjuEx3449). Scale bar: 10 and 5 μm (zoom in). Right, Pearson’s colocalization analysis of cytosolic MAI-2-GFP and TOMM-20::mKate2 before and after wounding, as shown in the left images. Statistical analysis was performed using the Mann–Whitney test. Data are mean ± SD (n = 31 ROIs); ***, P < 0.001. (D) Representative confocal images of cIF1-GFP fusion protein localization before and after laser wounding. Strains: Phyp-7-TOMM-20::mKate2(zjuSi126);Pcol-19-IF1(ΔMTS)(20–106 aa)::GFP (zjuEx3447). Scale bar: 10 and 5 μm (zoom in). Right, Pearson’s colocalization analysis of cIF1-GFP and TOMM-20::mKate2 before and after wounding to the left images. Statistical analysis was performed using the Mann–Whitney test. Data are mean ± SD (n = 25 and 31 ROIs, respectively); ***, P < 0.001. (E–G) Representative images of MAI-1 truncation mutants before and after wounding. Strains: Pcol-19-TOMM-20::GFP(zjuSi42); Pcol-19-MAI-1::mKate2(zjuEx3209), Pcol-19-MAI-1(1–41)::mKate2(zjuEx3212),and Pcol-19-MAI-1(39–88)::mKate2(zjuEx3461). Scale bar, 10 and 5 μm (zoom in). Right, quantification of fluorescence intensity along 15 μm lines across the unwound area and wound site. The white dashed circle indicates the wound site. UW, unwounded; W, wounded. The white dashed lines indicate the analysis region.