Figure 5. Late phase of amylin monomer internalization in RIN-m5F cells is independent of macropinocytosis.
Cells were either treated with EIPA, CytD and Wort for 1 hour or transfected with the dynamin mutant construct, DN dyn1K44A for 16–18 hours followed by human amylin incubation at either 100 nM or 10 µM for an additional 24 hours at 37°C. Dextran was sequentially added after incubating cells with 10 µM human amylin. Confocal microscopy (A) and whole cell analysis (B–D) showed no change in cellular distributions of monomers at 100 nM (B) or 10 µM (C) in the presence of EIPA, CytD, and Wort or DN dyn1K44A when compared to controls. NS P>0.1, hA vs. hA/treatments, n = 9. However, dextran (D) internalization was significantly reduced when treated with macropinocytotic inhibitors but not with DN dyn1K44A. ##P<0.01, dextran vs. dextran/inhibitors and NS, P>0.1, dextran vs. dextran/dyn1K44A, n = 9. Significance established by ANOVA followed by Dunnett-Square test. Bar 5µm.
