Endomembrane System of Dinoflagellates

Abstract

Although the various organelles of mammalian cells are in the focus of this book, it should be noted that unicellular organisms have provided invaluable information about the biogenesis, molecular structure and function of various cellular organelles, since their principles have been found to be phylogenetically highly conserved. As a case in point, studies in the yeast Saccharomyces cerevisiae were of fundamental importance for the molecular dissection of the secretory pathway and of autophagy. Despite, in wild type Saccharomyces cerevisiae, elements of the rough endoplasmic reticulum are scarce and stacks of flat cisternae building a Golgi apparatus resembling the one of mammalian cells are rarely found. However, in sec7 and sec14 secretory mutants, Golgi apparatus composed of cisternal stacks could be readily observed at the non-permissive temperature. Other unicellular organisms such as the parasitic protists contain a comparatively well developed endomembrane system.