Panel A shows confocal microscopy images and quantification graph of mitochondrial damage after mechanical needle injury. Panel B shows confocal microscopy images of mitochondrial structural disruption following severe cellular cold stress. Panel C shows confocal microscopy images of mitochondrial damage responses across multiple mitochondrial regulatory mutant backgrounds. Panel D shows confocal microscopy images and fluorescence intensity graphs of damaged enlarged mitochondria in metabolic mutants.
MAI-1 labels damaged mitochondria induced by diverse stresses. (A) Left, representative confocal image of MAI-1::GFP and TOMM-20::mKate2 in the epidermal hyp7 before and after mechanical puncture. Strains: Phyp-7-TOMM-20::mKate2 (zjuSi126); Pcol-19-MAI-1::GFP (zjuSi510). The white dashed circle indicates the wound site. Scale bar, 10 and 5 μm (zoom in). UW, unwounded. Right, quantitation of accumulated MAI-1::GFP in the wounding site before and after wounding 5 min. Statistical analysis was performed using the Mann–Whitney test. Data are mean ± SD (n = 39 and 52, respectively). ***P < 0.001. (B) Representative confocal image of mito::GFP and TOMM-20::mKate2 in the epidermal hyp7 before and after cold shock (−20°C) stress. The white arrowheads indicate damaged mitochondria. Strains: Phyp-7-TOMM-20::mKate2 (zjuSi126); Pcol-19-mito::GFP (zjuSi197). Scale bar, 10 and 5 μm (zoom in). (C) Representative confocal image of MAI-1::GFP in the epidermal hyp7 before and after wounding in different genetic backgrounds. Strains: fzo-1(tm1133), drp-1(tm1108), eat-3(tm1107), chch-3(tm2336), pink-1(ok3538), and Pcol-19-MAI-1::GFP (zjuSi510). Scale bar, 10 and 5 μm (zoom in). UW, unwounded; W, wounded. (D) Representative confocal image of MAI-1::GFP and TOMM-20::mKate2 in aass-1 and argn-1 mutant. Enlarged and damaged mitochondria colocalize with MAI-1::GFP. Strains: aass-1 (yq211), argn-1 (yq187); Phyp-7-TOMM-20::mKate2 (zjuSi126); Pcol-19-MAI-1::GFP (zjuSi510). Scale bar, 10 and 5 μm (zoom in). Right, quantification of fluorescence intensity along 15 μm lines across the wound site. The white dashed lines indicate the analysis region.