Journal: bioRxiv
Article Title: A paradoxical relationship between mitochondrial calcium regulation and retinal ganglion cell degeneration after axon damage
doi: 10.64898/2026.05.13.724793
Figure Lengend Snippet: (A) Example in vivo 2-photon max intensity projections (mip) of cytoplasmic (Cyto, left) and mitochondrial (Mito, right) Twitch-2b expressed in retinal ganglion cells (RGCs) of VGlut2-Cre mice. (B) Swarm plots of homeostatic cyto- and mito-Ca 2+ levels, as measured by cpVenus (YFP) to mCerulean (CFP) FRET ratios, MWU test (cyto-T2b n = 868 RGCs from 14 retinas and 8 mice, mito-T2b n = 1066 RGCs from 19 retinas and 15 mice). (C) Average intensity projections (aip) of mito-T2b in vivo of the same RGCs at baseline and 4 days later. Magenta arrows indicate RGCs with higher baseline mito-Ca 2+ and green arrows indicate RGCs with lower mito-Ca 2+ levels. (D) Scatterplot of mito-Ca 2+ levels pre and 4 day follow-up timepoints. R = 0.45, (n = 205 RGCs from 5 retinas and 3 mice). (E) Swarm plots of change in mito-Ca 2+ levels from baseline to 4 day follow-up replotted from panel (D). (F) Example aips of mito-T2b at baseline and 10 min following intravitreal Ru265 injection. White arrows indicate RGCs with reduced mito-Ca 2+ . (G) Line graphs of mito-Ca 2+ levels before and 10 min after Ru265 injection. Individual RGCs are in blue, and mean is in black (n = 175 RGCs from 4 retinas and 4 mice). (H) Example aips of cyto-T2b at baseline and 10 min after intravitreal Ru265. White arrows indicate RGCs with increased cyto-Ca 2+ . (I) Line graphs of cyto-Ca 2+ levels before and 10 min after Ru265 injection. Individual RGCs are in orange, and mean is in black (n = 123 RGCs from 4 retinas and 4 mice). (J) Swarm plot comparing changes in Ca 2+ levels after Ru265 between cyto- and mito-T2b. Black bars are mean +/- SEM replotted from panels (G and I). (K) Example aips of KCNG4-Cre mito-T2b acquired with in vivo transscleral imaging. GCL = ganglion cell layer, IPL = inner plexiform layer, NFL = nerve fiber layer. Box indicates magnified region. (L) Representative confocal mips of fixed retinal wholemounts showing endogenous mito-T2b (yellow) and TOMM20 (cyan) immunostaining. Scale bars = 100 μm.
Article Snippet: For overexpression experiments, VGlut2-Cre mice were crossed with B6N.Cg-Gt(ROSA)26Sortm1(CAG-EGFP*)Thm/J (032675, Jackson Labs) mice for outer mitochondrial membrane-GFP expression (not analyzed/used).
Techniques: In Vivo, Injection, Imaging, Immunostaining