Edouard Chatton (1883-1947) and the dinoflagellate protists: concepts and models.

Edouard Chatton contributed to our knowledge of single-celled protoctists, especially ciliates and dinoflagellates, free-living and/or symbiotic, in relation to the marine invertebrate animals in which they reside. More than the description of many new families, genera and species, and of their life cycles, he anticipated several major concepts of cell biology, including the fundamental difference between prokaryote and eukaryote protists, long time before the advent of electron microscopy. These concepts included: the reproductive ability of the kinetosome-centriole system; the homology of the kinetosome with the mitotic centriole of animal cells; and the different kinds of mitotic systems. Chatton trained more than thirty student collaborators, among them Andre Lwoff, who won the 1965 Nobel Prize in Physiology or Medicine. Later, the great cell biologist Hans Ris and I completed Chatton's light microscopy descriptions on syndinian mitosis dinoflagellate. We had at our disposal sophisticated electron microscopes as well as biochemical and molecular techniques and thus succeeded in corroborating the correct interpretation by Chatton of chromosome structure and mitotic cytology.