Figure S1.

Notch1 cortical signaling influences mammary duct morphogenesis. (A) Western blot of lysates from scramble control (SCR), NOTCH1^KO, and ICD^KO cells immunoblotted for Notch1, Notch2, Notch3, and Notch4. (B) mRNA transcript expression of Notch1 target genes HES1 and HEY1 measured by qPCR in SCR, NOTCH1^KO, ICD^KO, and dnMAML-expressing cells. Average qPCR reads from n = 3 independent experiments. (C) Top: Phase contrast micrographs of SCR ducts over a 7-d timecourse shown at days 1, 3, 5, and 7 after seeding. Bottom: Phase-contrast images of NOTCH1^KO ducts over a 7-d timecourse shown on days 1, 3, 5, and 7 after seeding. Scale bars, 150 µm. (D) Temporal projection micrographs of a timelapse of SCR and NOTCH1^KO ducts perfused with 4 µm polystyrene beads (green). Scale bar, 200 µm. (E) Medial confocal slice micrographs from SCR, NOTCH1^KO, ICD^KO, and dnMAML ducts labeled with Hoechst (black). Scale bar, 50 µm. For plot B, mean ± SEM; one-way ANOVA with Tukey’s post-hoc test, ****P < 0.0001, ns denotes non-significant. Source data are available for this figure: SourceData FS1.