Fig. 4: PCBP2 condensates disrupt mitochondrial morphology and function.
From: Pharmacologic inhibition of PCBP2 biomolecular condensates relieves Alzheimer’s disease
a GSEA comparing pre- and post-sorted PCBP2-condensate fractions used a one-sided enrichment test; Multiple testing was controlled across gene sets using the Benjamini–Hochberg FDR. b Live-cell imaging (upper) of SH-SY5Y-PCBP2 cells stained with MitoTracker Green. Quantitative analysis (lower) of mitochondrial morphology is measured by area, perimeter, aspect ratio (AR), and form factor (FF) values using a computer-assisted morphometric system. Scale bar, 10 µm. c Immunofluorescence images (upper) of SH-SY5Y-PCBP2 cells stained for TOM20 (green), DAPI (blue), and PCBP2 (red). These descriptors (lower) also included area, perimeter, AR, and FF. Scale bar, 10 µm. d Transmission electron microscopy (TEM) images show an impairment of mitochondrial morphology in SH-SY5Y-PCBP2 cells. Mitochondria indicated by the white arrows in the left panels are displayed with higher magnification in the right panels. Black arrows indicate damaged mitochondria with ridge reduction or absence. Scale bar, 2 µm or as indicated. Mitochondrial (mito) mean number and length were quantified. e Live-cell imaging of reactive oxygen species (ROS) levels in SH-SY5Y cells transiently transfected with vector (Vector), PCBP2, or incubated with 50 µM hydrogen peroxide (H2O2) for 4 h without transfection. ROS was labeled with the DCFH-DA probe. Scale bar, 10 µm. f Oxygen consumption rate (OCR) between SH-SY5Y and SH-SY5Y-PCBP2 cells is assessed using a Seahorse XF24 Extracellular Flux Analyzer, respectively. Statistical results are presented as bar graphs at the bottom. g Extracellular acidification rate (ECAR) between SH-SY5Y and SH-SY5Y-PCBP2 cells is assessed using a Seahorse XF24 Extracellular Flux Analyzer, respectively. Statistical results are presented as bar graphs at the bottom. h Immunofluorescence images showing the colocalization of TOM20 (green) and PCBP2 (red) in SH-SY5Y-APP cells. Scale bar, 10 µm. PCC: Pearson’s correlation coefficient. i Live-cell imaging of reactive oxygen species (ROS) levels in SH-SY5Y-APP cells transiently transfected with siPCBP2 or a negative control (NC). ROS levels were visualized with the DCFH-DA probe. Scale bar, 10 µm. Data: mean ± SD (b–d, f–h) and analyzed by two-tailed Student’s t-test (b–d, f–h). In vitro: n = 3 biological replicates (b–e, f [SH-SY5Y], h, i); n = 4 biological replicates (f [SH-SY5Y-PCBP2]); n = 10 biological replicates (g). Source data are provided as a Source Data file.
