Journal: Nature Structural & Molecular Biology
Article Title: MitoPerturb-Seq identifies gene-specific single-cell responses to mitochondrial DNA depletion and heteroplasmy
doi: 10.1038/s41594-026-01779-7
Figure Lengend Snippet: ( A ) Expression profiles of indicated cell-cycle genes across cell-cycle pseudotime determined by tricycle. ( B ) Percentage of cells in each cell-cycle phase in Tfam , Opa1 , Polg KO cells, post-Mixscape, compared to non-targeting gRNA cells. Chi-squared tests with multiple testing correction (Bonferroni); ns, not significant. ( C ) Schematic showing the expression patterns of the PIP-FUCCI fluorescent reporters Cdt1-mVenus and Geminin-mCherry across the cell-cycle. ( D,E ) Gating strategies used to isolate cells for mtDNA CN measurements based on cell-cycle phase for both inter-phase ( D ) and intra-phase ( E ) comparisons. ( F,G ) Western blot ( F ) and ddPCR measurements ( G ) showing KD of TFAM protein ( F ) and reduced mtDNA CN ( G ) in HeLa cells transduced with two independent TFAM gRNAs. Vinculin is shown as a loading control ( F ). Number of individual cells per group is indicated in ( G ), data presented as mean values ± SD. One-way ANOVA with Tukey’s post-hoc test, **** p < 0.0001. ( H ) Map of the human mtDNA, highlighting the 7.5 Kb deletion present in the DeltaH2.1 cybrid cell line. ( I,J ) mtDNA CN ( I ) and heteroplasmy ( J ) of eight clonal populations isolated from the DeltaH2.1 cybrid cell line. Cell numbers per group indicated on graphs. Data presented as mean values +/- SD. One-way ANOVA of the mtDNA CN distributions was significant (p = 0.015); pairwise comparisons of all heteroplasmic clones to Clone 25 (0% heteroplasmy) using Tukey’s post-hoc test; ns, not significant. ( K ) Respirometry of DeltaH2.1 cybrid cells with increasing heteroplasmy levels, using Oroboros, showing baseline respiration (BR), proton-leak (PL), ATP-linked respiration (AR) and maximal respiratory capacity (MC). Three separate assays per clone. Data presented as mean values ± SD. One-way ANOVA with Tukey’s post-hoc test performed for each tested parameter, all significant pairwise comparisons are shown. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001. ( L,M ) Growth curves of DeltaH2.1 cybrid clones carrying different levels of heteroplasmy in high ( L ) and low ( M ) glucose culture medium. Confluency values averaged over 8 individual images per timepoint for each clone in each condition, data presented as mean values ± SEM. Figure created in BioRender. Van den Ameele, J. (2026) https://BioRender.com/j3ro7vq .
Article Snippet: Transfections were performed with cells at 80–90% confluency using TransIT-293 transfection reagent (Mirus, MIR2704) according to the manufacturer’s instructions.
Techniques: Expressing, Western Blot, Transduction, Control, Isolation, Clone Assay