Fig. 3.
Apical constriction is not due to inhibiting endocytosis, and dynamin is enriched at the apical junctional region. (A) Maximum intensity projection images of cells expressing Dyn2wt-GFP (Left Upper, green) and Dyn2K44A-GFP (Left Lower, green) that were incubated with TxRed-transferrin (red) and stained for ZO-1 (blue). (B) Single plane images taken below AJC of Dyn2K44A-GFP-expressing cells subjected to TxRed-dextran applied either apically or basolaterally and imaged live. (C) Mean ratio (AP/L) for cells expressing Dyn2wt-GFP, Dyn2K44A-GFP, Eps15wt-GFP, Eps15Δ95/295-GFP, FLAG-Cav1wt, FLAG-Cav1Y14F, or Eps15Δ95/295-GFP and FLAG-Cav1Y14F in at least three separate experiments. **, P < 0.001. (D) Mean ratio (AP/L) for cells expressing Dyn2wt-GFP, Dyn2K44A-GFP, Dyn2K44A-CeFP, and Eps15Δ95/295-GFP, or Dyn2K44A-GFP and FLAG-Cav1Y14F from two independent experiments. (E) Single-plane images of a monolayer stained for dynamin (green) and ZO-1 (red) at the AJC (Upper) and 1 μm below the AJC (Lower). Note dynamin enrichment (arrows) at the AJC but not at the basolateral membranes. (F) XZ sections of cells expressing Dyn2wt-GFP (Left) and Dyn2K44A-GFP (Right) before and after treatment with 0.01% digitonin. Note the enrichment of Dyn2K44A-GFP relative to Dyn2wt-GFP (arrows). (G) FRAP recovery kinetics for Dyn2wt-GFP and Dyn2K44A-GFP in cells expressing an individual chimera.