title: Asynchronous spore germination in isogenic natural isolates of Saccharomyces paradoxus.
abstract: Spores from wild yeast isolates often show great variation in the size of colonies they produce, for largely unknown reasons. Here we measure the colonies produced from single spores from six different wild Saccharomyces paradoxus strains. We found remarkable variation in spore colony sizes, even among spores that were genetically identical. Different strains had different amounts of variation in spore colony sizes, and variation was not affected by the number of preceding meioses, or by spore maturation time. We used time-lapse photography to show that wild strains also have high variation in spore germination timing, providing a likely mechanism for the variation in spore colony sizes. When some spores from a laboratory strain make small colonies, or no colonies, it usually indicates a genetic or meiotic fault. Here, we demonstrate that in wild strains spore colony size variation is normal. We discuss and assess potential adaptive and non-adaptive explanations for this variation.
authors.affiliation: Max Planck Institute for Evolutionary Biology, August-Thienemann Straße 2, D-24306 Plön, Germany rike.stelkens@evolbio.mpg.de.
authors.forename: Rike B
authors.initials: RB
authors.lastname: Stelkens
authors.affiliation: Max Planck Institute for Evolutionary Biology, August-Thienemann Straße 2, D-24306 Plön, Germany Institute of Biology, University of Leiden, Sylviusweg 72, NL-2300 RA Leiden, The Netherlands University of Manchester, Faculty of Life Sciences, Oxford Road, Manchester M13 9PL, UK.
authors.forename: Eric L
authors.initials: EL
authors.lastname: Miller
authors.affiliation: Max Planck Institute for Evolutionary Biology, August-Thienemann Straße 2, D-24306 Plön, Germany The Galton Laboratory, Department of Genetics, Evolution, and Environment, University College, London, Gower Street, London WC1E 6BT, UK.
authors.forename: Duncan
authors.initials: D
authors.lastname: Greig
mesh_terms: D008853:Microscopy; D012440:Saccharomyces / Q000254:growth & development* / Q000302:isolation & purification; D013172:Spores, Fungal / Q000254:growth & development*; D059008:Time-Lapse Imaging
keywords: Saccharomyces paradoxus; bet hedging; colony size; germination asynchrony