Induction of autophagy causes dramatic changes in the subcellular distribution of GFP-Rab24

Traffic. 2002 Jul;3(7):472-82. doi: 10.1034/j.1600-0854.2002.30704.x.


Rab GTPases comprises a large family of proteins, with more than 50 gene products localized in distinct subcellular compartments. Rab24 is a member of this family whose function is not presently known. In order to elucidate the role of this protein we have generated a GFP-tagged Rab24 and studied the distribution of this chimera by fluorescence microscopy. GFP-Rab24 showed a perinuclear reticular localization that often encircled the nucleus. This reticular pattern partially overlapped with ER markers, cis-Golgi, and the ER-Golgi intermediate compartment. Surprisingly, when GFP-Rab24-transfected cells were starved to induce autophagy the distribution of the protein changed dramatically. GFP-Rab24 localized in large dots, cup-shaped structures and ring-shaped vesicles. Some of these vesicles were labeled with monodansylcadaverine, a specific autophagosome marker. In the presence of vinblastine, an agent that induces the formation of very large autophagic vesicles, GFP-Rab24 accumulated in the large vacuoles that were also labeled by monodansylcadaverine. Furthermore, Rab24 colocalized with LC3, a mammalian homolog of the yeast protein Apg8/Aut7, an essential gene for autophagy. This is the first report indicating that Rab24 localizes on autophagosomes, suggesting that this Rab protein is involved in the autophagic pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Androstadienes / pharmacology
  • Animals
  • Autophagy / drug effects
  • Autophagy / physiology*
  • CHO Cells
  • Cadaverine / analogs & derivatives*
  • Cadaverine / metabolism
  • Cricetinae
  • Ethylmaleimide / pharmacology
  • Green Fluorescent Proteins
  • Luminescent Proteins / metabolism
  • Phagosomes / metabolism
  • Recombinant Fusion Proteins / metabolism
  • Subcellular Fractions / metabolism
  • Vacuoles / metabolism
  • Wortmannin
  • rab GTP-Binding Proteins / metabolism*


  • Androstadienes
  • Luminescent Proteins
  • Recombinant Fusion Proteins
  • Green Fluorescent Proteins
  • Rab24 protein, mouse
  • rab GTP-Binding Proteins
  • monodansylcadaverine
  • Cadaverine
  • Ethylmaleimide
  • Wortmannin