Fig. 4: Decrease in E-cadherin levels at junctions mediates the mislocalization of myosin II cables. | Nature Communications

Fig. 4: Decrease in E-cadherin levels at junctions mediates the mislocalization of myosin II cables.

From: Inhibition of negative feedback for persistent epithelial cell–cell junction contraction by p21-activated kinase 3

Fig. 4

a Representative images of split MRLC::GFP cables (orange arrowheads) at junctions. Scale bar, 5 μm. b Mean ± S.D. of the lengths of junctions when the MRLC::GFP cables initiated splitting. Dots indicate the copy number of each E-cadherin allele. Parentheses, the number (n) of examined junctions from 3–6 biologically independent pupae per genotype. P-value by two-tailed Tukey’s test. c Representative magnified time-lapse images (duplicated) of E-Cad::GFP at junctions from >3 independent experiments. E-Cad::GFP-positive protrusions are indicated by arrowheads (top) or masked (bottom), respectively. Broken lines indicate the local decrease in E-Cad::GFP levels at the bases of the protrusions. Scale bar, 3 μm. d, e The mean ± S.D. of the height and width (length of the base) of E-Cad::GFP-positive protrusions. n = 77 (Control) or 74 (Pak3 RNAi) protrusions from 5 (Control) and 7 (Pak3 RNAi) biologically independent pupae (c–e). P-value by unpaired t-test. f A schematic illustration of the junctional regions (boxed with broken lines) for measuring the mean E-Cad::GFP levels at the base of small actin protrusions in the control cells or the large protrusions in Pak3 RNAi cells (orange), and its proximity (gray). g Images of junctions with E-Cad::GFP and Lifeact::Ruby in Pak3 RNAi cells. Dots indicate the copy number of each E-cadherin allele. Broken boxes indicate quantified areas; each color corresponds with the colors in (f). Scale bar, 3 μm. h Mean ± S.D. of the ratio of Intbase and Intproximity per junction. Parentheses, the number (n) of small (control) or the large (Pak3 RNAi) actin protrusions examined from 4 (the control and Pak3 RNAi) and 3 (Pak3 RNAi with Ubi-E-Cad::GFP) biologically independent pupae. Dots indicate the copy number of each E-cadherin allele. P-value by one-sample t-test with a test value of 1. Genotypes: a, b MRLCAX3/Y;MRLC-MRLC::GFP/+;AbdB-Gal4, UAS-H2B::ECFP/+ (Control), MRLCAX3/Y;MRLC-MRLC::GFP/UAS-Lifeact::Ruby;AbdB-Gal4, UAS-H2B::ECFP/UAS-Pak3 RNAi, MRLCAX3/Y;MRLC-MRLC::GFP/UAS-Abi RNAi;AbdB-Gal4, UAS-H2B::ECFP/UAS-Pak3 RNAi, MRLCAX3/Y;MRLC-MRLC::GFP/UAS-SCAR RNAi;AbdB-Gal4, UAS-H2B::ECFP/UAS-Pak3 RNAi, and MRLCAX3/Y;MRLC-MRLC::GFP/UAS-E-cadherin;AbdB-Gal4, UAS-H2B::ECFP/UAS-Pak3 RNAi; c–e +/Y;E-Cad::GFP;AbdB-Gal4, UAS-H2B::ECFP/+ (Control) and +/Y;E-Cad::GFP (KI);AbdB-Gal4, UAS-H2B::ECFP/UAS-Pak3 RNAi; g, h +/Y;E-Cad::GFP (KI)/UAS-Lifeact::Ruby;AbdB-Gal4/+ (Control), +/Y;E-Cad::GFP (KI)/UAS-Lifeact::Ruby;AbdB-Gal4/UAS-Pak3 RNAi, and +/Y;Ubi-E-Cad::GFP/UAS-Lifeact::Ruby;AbdB-Gal4/UAS-Pak3 RNAi. Source data are provided as a Source data file.

Back to article page