Effect of starvation on the endocytic pathway in Dictyostelium cells

Eukaryot Cell. 2010 Mar;9(3):387-92. doi: 10.1128/EC.00285-09. Epub 2010 Jan 22.

Abstract

Dictyostelium discoideum amoebae have been used extensively to study the structure and dynamics of the endocytic pathway. Here, we show that while the general structure of the endocytic pathway is maintained in starved cells, its dynamics rapidly slow down. In addition, analysis of apm3 and lvsB mutants reveals that the functional organization of the endocytic pathway is profoundly modified upon starvation. Indeed, in these mutant cells, some of the defects observed in rich medium persist in starved cells, notably an abnormally slow transfer of endocytosed material between endocytic compartments. Other parameters, such as endocytosis of the fluid phase or the rate of fusion of postlysosomes to the cell surface, vary dramatically upon starvation. Studying the endocytic pathway in starved cells can provide a different perspective, allowing the primary (invariant) defects resulting from specific mutations to be distinguished from their secondary (conditional) consequences.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Protein Complex mu Subunits / genetics
  • Culture Media / pharmacology
  • Dictyostelium / drug effects
  • Dictyostelium / physiology*
  • Endocytosis / drug effects
  • Endocytosis / physiology*
  • Exocytosis / drug effects
  • Exocytosis / physiology
  • Food Deprivation
  • Kinetics
  • Lysosomes / drug effects
  • Lysosomes / physiology
  • Membrane Fusion / drug effects
  • Membrane Fusion / physiology
  • Phagocytosis / drug effects
  • Phagocytosis / physiology
  • Pinocytosis / drug effects
  • Pinocytosis / physiology
  • Protozoan Proteins / genetics
  • Stress, Physiological / physiology*
  • Transport Vesicles / drug effects
  • Transport Vesicles / physiology
  • Vesicular Transport Proteins / genetics

Substances

  • Adaptor Protein Complex mu Subunits
  • Culture Media
  • Protozoan Proteins
  • Vesicular Transport Proteins