Neuroglian and DE-Cadherin Activate Independent Cytoskeleton Assembly Pathways in Drosophila S2 Cells

Abstract

The cytoskeletal proteins spectrin and ankyrin colocalize with sites of E-cadherin-mediated cell–cell adhesion in mammalian cells. Here we examined the effects of Drosophila DE-cadherin expression on spectrin and ankyrin in Drosophila S2 tissue culture cells. DE-cadherin caused a dramatic change in the cytoplasmic concentration and distribution of armadillo, the Drosophila homolog of β catenin. However, DE-cadherin expression had no detectable effect on the quantity or subcellular distribution of ankyrin or spectrin. In reciprocal experiments, recruitment of ankyrin and αβ spectrin to the plasma membrane by another cell adhesion molecule, neuroglian, had no effect on the quantity or distribution of armadillo. The results indicate that DE-cadherin–catenin complexes and neuroglian-spectrin/ankyrin complexes form by nonintersecting pathways. Recruitment of spectrin does not appear to be a conserved feature of DE-cadherin function.