genetic structure of two protist species (myxogastria, amoebozoa) suggests asexual reproduction in sexual amoebae两个原生生物物种遗传结构(myxogastria amoebozoa)建议性变形虫的无性生殖.pdfVIP

Genetic Structure of Two Protist Species (Myxogastria, Amoebozoa) Suggests Asexual Reproduction in Sexual Amoebae 1 2 3 1 Anna Maria Fiore-Donno *, Yuri K. Novozhilov , Marianne Meyer , Martin Schnittler 1 University of Greifswald, Institute of Botany and Landscape Ecology, Greifswald, Germany, 2 V. L. Komarov Institute of Botany, Russian Academy of Sciences, Laboratory for Systematics and Geography of Fungi, St. Petersburg, Russia, 3 Le Bayet, Rognaix, France Abstract Plasmodial slime molds (Myxogastria or Myxomycetes) are common and widespread unicellular organisms that are commonly assumed to have a sexual life cycle culminating with the formation of often macroscopic fruiting bodies that efficiently disseminate spores. However, laboratory studies based on mating compatibility revealed the coexistence of asexual as well as sexual strains. To test this hypothesis in natural populations, we investigated the genetic variability of two ´ species of the genus Lamproderma. Detailed ecological releves were carried out in 2007 and 2009 in several deep ravines in the Elbsandsteingebirge (Saxony, south-eastern Germany). Morphological characters of 93 specimens of Lamproderma were recorded and genetic analyses, based on the small subunit ribosomal gene, the internal transcribed spacer 1 and partial elongation factor 1a sequences were carried out for 52 specimens. Genetic analyses showed the existence of two major clades, each composed of several discrete lineages. Most of these lineages were composed of several identical sequences (SSU, ITS 1 and EF-1a) which is explained best by an asexual mode of reproduction. Detrended Correspondence