Microtubule- and motor-dependent fusion in vitro between apical and basolateral endocytic vesicles from MDCK cells

Cell. 1990 Aug 24;62(4):719-31. doi: 10.1016/0092-8674(90)90117-w.


The pathways of endocytosis from the apical and the basolateral domains of epithelial MDCK cells are known to converge at the level of late endosomes in vivo. We have now reconstituted the meeting process in a cell-free assay that measures the fusion of apically and basolaterally derived endocytic vesicles with late endosomes. Our results show that this in vitro process requires the presence of polymerized microtubules, as does the convergence of the two pathways in vivo, and also depends on the presence of microtubule binding proteins, in particular the mechanochemical motors kinesin and cytoplasmic dynein.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / physiology
  • Animals
  • Biological Transport, Active / drug effects
  • Cattle
  • Cell Line
  • Cell-Free System
  • Dyneins / physiology
  • Endocytosis*
  • Epithelium / physiology*
  • Epithelium / ultrastructure
  • Intracellular Membranes / physiology*
  • Kinesin
  • Membrane Fusion*
  • Microscopy, Electron
  • Microtubule-Associated Proteins / physiology
  • Microtubules / physiology*
  • Time Factors
  • Vanadates / pharmacology


  • Microtubule-Associated Proteins
  • Vanadates
  • Adenosine Triphosphatases
  • Dyneins
  • Kinesin