Fig. S8

APLNR signaling modulates the polarization of human arterial endothelial cells.

(a-b′) Immunofluorescence staining of HUAECs transfected with si SC or si APLNR subjected to laminar flow at 20 dynes/cm² for 18 hours. Cells were fixed and stained with the GM130 Golgi antibody (green), Phalloidin (red) and DAPI (blue). White arrowheads point to polarized ECs (i.e., Golgi apparatus positioned within ±45° against the direction of flow (G1)). Yellow arrowheads point to depolarized ECs (i.e., Golgi positioned within + 45° to +180° and +180° to -45° against the direction of flow (G2-G4)). (c) Quantification of polarization of HUAECs subjected to laminar flow at 20 dynes/cm² for 18 hours transfected with si SC or si APLNR. n > 300 cells, from at least three independent experiments. (d-g′) Fluorescent images of HUAECs transfected with ARRB-GFP as well as si SC or si APLNR subjected to laminar flow at 20 dynes/com2 for 15 mins. Red arrowheads point to plasma membrane localization of ARRB-GFP after 15 mins of laminar flow. (h) Quantification of ARRB-GFP membrane localization of HUAECs subjected to static condition or laminar flow at 20 dynes/cm² for 15 mins transfected with si SC or si APLNR. *** P<0.05. Scale bars, 20 µm. Error bars, SEM.