Abstract

Biological processes such as motility and phagocytosis (1) are conserved and thus, their study in the common amoeba Dictyostelium discoideum, a biochemically and genetically tractable professional phagocyte, is directly relevant to higher organisms. In recent years, it has become a popular model system to study the involvement of the actomyosin cytoskeleton in vesicle formation and transport in particular during phagolysosome biogenesis. For example, class I myosins play a variety of roles during phagocytic uptake, membrane retrieval, phagosome reneutralisation and exocytosis (2). At every stage, they collaborate with a variety of other molecular machineries, including actin, the WASH complex and Dynamin A (3, 4, 5). In addition, preparation for exocytosis involves the conserved Exocyst complex. The involvement or Rab8a-mediated Exocyst function was best studied during the kiss-and-run discharge of the contractile vacuole system. In conclusion, our investigations of molecular mechanisms of membrane trafficking in Dictyostelium continue to unravel novel roles for many highly studied conserved proteins.

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