Mechanism of Autophagy in Permeabilized Hepatocytes

Evidence for Regulation by GTP Binding Proteins
  • Motoni Kadowaki
  • Rina Venerando
  • Giovanni Miotto
  • Glenn E. Mortimore
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 389)


Autophagic vacuoles in hepatocytes are formed from membranes of rough and smooth endoplasmic reticulum (ER) by processes that are under immediate physiologic control by amino acids, insulin, and glucagon (reviewed in 1). Little, though, is known of the molecular steps involved. Microinjection (2) and electropermeabilization (3) have been used to introduce markers into cells and newly formed vacuoles. But because the pores are transient, observations are restricted to events that occur after membrane resealing. In order to gain access to autophagy under steady state conditions, we permeabilized hepatocytes with α-toxin from Staphylococcus aureus, an agent which forms stable ≈1.5 nm channels that limit exchange to molecules of approximately 1000 Da (4). Such pores will admit nucleotides and labeled residualizing probes without loss of cell proteins, a desirable, possibly necessary, condition for evaluating autophagically-mediated proteolysis.


Volume Density Autophagic Vacuole Cytoplasmic Sequestration Membrane Reseal Permeabilized Hepatocyte 
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Copyright information

© Plenum Press, New York 1996

Authors and Affiliations

  • Motoni Kadowaki
    • 1
  • Rina Venerando
    • 2
  • Giovanni Miotto
    • 2
  • Glenn E. Mortimore
    • 3
  1. 1.Department of Applied BiochemistryNiigata UniversityNiigataJapan
  2. 2.Dipartimento di Chimica BiologicaUniversità Degli Studi di PadovaPadovaItaly
  3. 3.Department of Cellular and Molecular PhysiologyThe Pennsylvania State UniversityHersheyUSA

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