Journal: bioRxiv
Article Title: The Notch1 intracellular domain orchestrates mechanotransduction of fluid shear stress
doi: 10.1101/2025.07.13.663563
Figure Lengend Snippet: (A) Left: Fluorescence micrographs of co-culture of hdBECs expressing mEmerald (green) or mApple (magenta) under flow. Scale bar, 5 μm. Inset: High magnification micrograph of the cell-cell interface with mApple, mEmerald, and Notch1 ECD (cyan). Yellow inset: XZ orthogonal projection. Scale bar, 5 μm. Right: experimental schematic. (B) Fluorescence micrographs of hdBECs pretreated for 1 h with 10 μM DAPT, 1 μM BB94 or DMSO vehicle control and cultured under flow. Scale bar, 25 μm. (C) Quantification of Notch1 polarization in hdBECs treated with DAPT, BB94, or DMSO vehicle control under flow. n ≥ 10 fields of view from three independent experiments. (D) Super-resolution by optical pixel reassignment fluorescence micrographs of the downstream cell-cell interface of flow-polarized hdBECs. Scale bar, 5 μm. (E) Line scan quantification of relative Notch1 ECD (magenta) and Notch1 ICD (green) distribution (representative yellow dashed line). n = 10 profiles. (F) Fluorescence time series from live cell movie of hdBECs labeled with AF647-Notch1 ECD antibody under flow. Pseudo-colored to depict cell-cell boundaries. Insets (i) and (ii) of distinct polarized domains where individual particles (red circles) are tracked over time moving retrograde opposite the direction of flow. Time scale (min:sec). Scale bar, 5 μm. (G) Schematic illustrating pulse-chase Notch1 ECD antibody labeling experiments. (H) Fluorescence micrographs of internalized Notch1 in SCR and DLL4 KO cells under flow conditions from pulse-chase labeling of Notch1 ECD (black). Scale bar, 25 μm. (I) Quantification of endocytosed Notch1 in SCR versus DLL4 KO cells. n ≥ 10 fields of view from three independent experiments. For all plots, mean ± SD; one-way Anova with Tukey’s post-hoc test, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, ns denotes non-significant.
Article Snippet: Antibodies against Notch1 V1754 (V1744 in mice, D3B8, 1:500 WB), Notch1 ICD (D1E11, 1:200 IF, 1:1000 WB), GAPDH (14C10, 1:5000 WB), Dll4 (D7N3H, 1:1000 WB), Jag1 (D4Y1R, 1:1000 WB), GFP (D5.1, 1:5000 WB), Annexin A2 (D11G2, 1:1000 WB, 1:200 IF), Presenilin-1 (E3L9X, 1:1000 WB), and Flotillin-2 (C42A3, 1:1000 WB) were from Cell Signaling Technologies.
Techniques: Fluorescence, Co-Culture Assay, Expressing, Control, Cell Culture, Labeling, Pulse Chase, Antibody Labeling