SKD1 AAA ATPase-dependent endosomal transport is involved in autolysosome formation

Cell Struct Funct. 2002 Feb;27(1):29-37. doi: 10.1247/csf.27.29.


Mouse SKD1 AAA ATPase is involved in the sorting and transport from endosomes; cells overexpressing a dominant-negative mutant, SKD1(E235Q) were defective in endosomal transport to both the plasma membranes and lysosomes (Yoshimori et al., 2000). In the present study, we demonstrated that overexpression of SKD1(E235Q) using an adenovirus delivery system caused a defect in autophagy-dependent bulk protein degradation. Morphological observations suggested that this inhibition of autophagy results from an impairment of autolysosome formation. SKD1(E235Q) overexpression also inhibited transport from endosomes to autophagosomes, an event normally occurring prior to fusion with lysosomes. These results indicate that SKD1-dependent endosomal membrane trafficking is required for formation of autolysosomes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATPases Associated with Diverse Cellular Activities
  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism*
  • Adenoviridae / genetics
  • Amino Acid Substitution
  • Autophagy / physiology*
  • Biological Transport / physiology
  • Endosomal Sorting Complexes Required for Transport
  • Endosomes / physiology*
  • HeLa Cells / metabolism
  • Humans
  • Lipid Metabolism
  • Lysosomes / physiology*
  • Membrane Fusion / physiology
  • Phagosomes / physiology
  • Point Mutation
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Vacuolar Proton-Translocating ATPases
  • Vesicular Transport Proteins


  • Endosomal Sorting Complexes Required for Transport
  • Repressor Proteins
  • Vesicular Transport Proteins
  • Adenosine Triphosphatases
  • Vacuolar Proton-Translocating ATPases
  • ATPases Associated with Diverse Cellular Activities
  • VPS4A protein, human