Neuroglian and DE-cadherin activate independent cytoskeleton assembly pathways in Drosophila S2 cells

The cytoskeletal proteins spectrin and ankyrin colocalize with sites of E-c adherin-mediated cell-cell adhesion in mammalian cells. Here we examined th e effects of Drosophila DE-cadherin expression on spectrin and ankyrin in D rosophila 52 tissue culture cells. DE-cadherin caused a dramatic change in the cytoplasmic concentration and distribution of armadillo the Drosophila homolog of beta 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 cup spectrin to the p lasma 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. (C) 1999 Academic Press.