Endophilin-A3 and Galectin-8 control the clathrin-independent endocytosis of CD166

Nat Commun. 2020 Mar 19;11(1):1457. doi: 10.1038/s41467-020-15303-y.

Abstract

While several clathrin-independent endocytic processes have been described so far, their biological relevance often remains elusive, especially in pathophysiological contexts such as cancer. In this study, we find that the tumor marker CD166/ALCAM (Activated Leukocyte Cell Adhesion Molecule) is a clathrin-independent cargo. We show that endophilin-A3-but neither A1 nor A2 isoforms-functionally associates with CD166-containing early endocytic carriers and physically interacts with the cargo. Our data further demonstrates that the three endophilin-A isoforms control the uptake of distinct subsets of cargoes. In addition, we provide strong evidence that the construction of endocytic sites from which CD166 is taken up in an endophilin-A3-dependent manner is driven by extracellular galectin-8. Taken together, our data reveal the existence of a previously uncharacterized clathrin-independent endocytic modality, that modulates the abundance of CD166 at the cell surface, and regulates adhesive and migratory properties of cancer cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Animals
  • Antigens, CD / metabolism*
  • Cell Adhesion
  • Cell Adhesion Molecules, Neuronal / metabolism*
  • Cell Line, Tumor
  • Cell Membrane / metabolism
  • Cell Movement
  • Chlorocebus aethiops
  • Clathrin / metabolism
  • Endocytosis*
  • Fetal Proteins / metabolism*
  • Fibroblasts
  • Galectins / genetics
  • Galectins / metabolism*
  • Gene Knockdown Techniques
  • Humans
  • Intravital Microscopy
  • Mice
  • Neoplasms / pathology*
  • RNA, Small Interfering
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism

Substances

  • ALCAM protein, human
  • Adaptor Proteins, Signal Transducing
  • Antigens, CD
  • Cell Adhesion Molecules, Neuronal
  • Clathrin
  • Fetal Proteins
  • Galectins
  • LGALS8 protein, human
  • RNA, Small Interfering
  • Recombinant Proteins
  • SH3GL3 protein, human