Fig. 7: PMCA4b promotes pre-lumen formation in 2D cultures of MCF-7 cells.
From: The calcium pump PMCA4b promotes epithelial cell polarization and lumen formation
a Phalloidin staining of parental, PMCA4 specific-shRNA (sh-PMCA4), GFP-PMCA4b and GFP-PMCA4bLA-expressing MCF-7 cell lines. White arrows point to the pre-lumens. b Phalloidin staining of GFP-PMCA4b-expressing MCF-7 cells. The white line encircles a pre-lumen. White arrows point to phalloidin and PMCA4b double-positive vesicles. c WGA uptake assay on GFP-PMCA4b-expressing MCF-7 cells with 20 min incubation after WGA removal. Pre-lumen creating cells are encircled with white line. d A schematic figure of a typical pre-lumen structure in (a) 2D cell culture. e Statistical analysis of pre-lumen formation in control and NAV2729 treated parental, PMCA4 specific shRNA (sh-PMCA4), GFP-PMCA4b and GFP-PMCA4bLA-expressing MCF-7 cell lines. Graph displays means with 95% confidence intervals corrected with the total area of the images; data were collected from 2 independent experiments, n(sh-PMCA4) = 23, n(sh-PMCA4+NAV2729) = 21, n(MCF-7) = 26, n(MCF-7 + NAV2729) = 22, n(PMCA4b) = 25, n(PMCA4b+NAV2729) = 23, n(PMCA4bLA) = 23, n(PMCA4bLA + NAV2729) = 17 images. Data were analyzed with Kruskal–Wallis and Dunn’s multiple comparisons tests, adjusted p values: nsp ≥ 0.05, *p < 0.05, **p < 0.01 ***p < 0.001; non-significant differences are not labeled. f Phalloidin staining of control and NAV2729 treated PMCA4 specific shRNA (sh-PMCA4) and GFP-PMCA4b-expressing MCF-7 cell lines. Scaled-down insets show the GFP-PMCA4b signal. The white arrowhead points to a pre-lumen.
