DOCSLIB.ORG

The Genetics of Life History Traits in the Fungus Neurospora Crassa

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Genetics of Life History Traits in the Fungus Neurospora Crassa The Genetics of Life History Traits in the Fungus Neurospora crassa The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Zimmerman, Kolea. 2016. The Genetics of Life History Traits in the Fungus Neurospora crassa. Doctoral dissertation, Harvard University, Graduate School of Arts & Sciences. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493574 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA The Genetics of Life History Traits in the Fungus Neurospora crassa A dissertation presented by Kolea Zimmerman to The Department of Organismic and Evolutionary Biology In partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Biology Harvard University Cambridge, Massachusetts April 2016 Copyright Notice This work is licensed under the Creative Commons Attribution-NonCommercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/. Advisor: Anne Pringle Author: Kolea Zimmerman The Genetics of Life History Traits in the Fungus Neurospora crassa Abstract The study of life histories is fundamental to understanding why some organisms live for a very short time while others live for a long time, why some produce thousands of offspring while others produce one, or why some need a mate to reproduce while others can do it on their own. The life histories of many animals and plants are well known because we can easily walk into a forest or field and measure them. Fungi, on the other hand, are hard to find and see even though they occur most everywhere in great numbers. In the three chapters of this dissertation, I uncover key aspects of the life history of the genetic model Neurospora crassa, a filamentous fungus. First, I present a novel algorithm for the design of crossing experiments, which test the reproductive abilities of individuals. The algorithm identifies a set of individuals (a “crossing- set”) from a larger pool of potential crossing-sets by maximizing the diversity of traits of interest, for example, maximizing the range of genetic and geographic distances between individuals included in the crossing-set. Second, I use the algorithm to select strains for a mating experiment designed to test for maternal effects—the impact of the mother’s phenotype on the offspring’s phenotype—across sexual reproduction in N. crassa. I measured offspring phenotypes from crosses of all possible pairs of 22 wild-isolated strains. Crosses encompassed reciprocals of 11 mating-type “A” and 11 mating-type “a” strains. After controlling for the genetic and geographic distances between strains in any individual cross, I found strong evidence for maternal control of perithecia (sporocarp) production, as well as maternal effects on spore numbers and spore germination. ! iii However, both parents exert equal influence on the percentage of spores that are pigmented, and size of pigmented spores. This experiment is proof of maternal effects in a fungus, an unprecedented discovery. Third, I compared the sexual spore viability data from the maternal effects experiment to asexual spore viability data I gathered for the same strains. I found a striking trade-off between the viabilities of sexual and asexual spores. I used genome-wide polymorphism data to determine the genetic basis of this trade-off and identified 36 single nucleotide polymorphisms (SNPs) significantly associated with both traits. All 36 of the identified SNPs exhibit antagonistic pleiotropy—they have opposing effects on asexual and sexual spore viability. Some of these SNPs occur in well-characterized genes involved in sexual reproduction, asexual reproduction, or both. Using the entire dataset of over 50,000 genome-wide SNPs, I show a negative correlation between effects SNPs on sexual and asexual viability across the entire N. crassa genome. These results suggest that a life history trade-off between asexual and sexual spore viabilities drives a large portion of the genetic variation in the N. crassa genome. ! iv TABLE OF CONTENTS ACKNOWLEDGEMENTS......................................................................................................................vii! CHAPTER.1...............................................................................................................................................1! ABSTRACT............................................................................................................................................................1! INTRODUCTION..................................................................................................................................................2! METHODS.............................................................................................................................................................5! RESULTS............................................................................................................................................................10! Figure!1.1!.........................................................................................................................................................................!11! Figure!1.2!.........................................................................................................................................................................!13! Figure!1.3!.........................................................................................................................................................................!15! Table!1.1!...........................................................................................................................................................................!16! Table!1.2!...........................................................................................................................................................................!16! Figure!1.4!.........................................................................................................................................................................!18! DISCUSSION......................................................................................................................................................19! ACKNOWLEDGEMENTS.................................................................................................................................24! CHAPTER.2.............................................................................................................................................25! ABSTRACT.........................................................................................................................................................25! INTRODUCTION...............................................................................................................................................27! Table!2.1!...........................................................................................................................................................................!30! METHODS..........................................................................................................................................................31! Figure!2.1!.........................................................................................................................................................................!33! Figure!2.2!.........................................................................................................................................................................!36! Table!2.2!...........................................................................................................................................................................!37! RESULTS............................................................................................................................................................46! Figure!2.3!.........................................................................................................................................................................!48! Table!2.3!...........................................................................................................................................................................!50! Figure!2.4!.........................................................................................................................................................................!51! Figure!2.5!.........................................................................................................................................................................!53! Table!2.4!...........................................................................................................................................................................!54! Figure!2.6!.........................................................................................................................................................................!56! Figure!2.7!.........................................................................................................................................................................!57! DISCUSSION......................................................................................................................................................58!
Load more

Recommended publications
  • Neurospora Crassa William K
    Published online 18 September 2020 Nucleic Acids Research, 2020, Vol. 48, No. 18 10199–10210 doi: 10.1093/nar/gkaa724 LSD1 prevents aberrant heterochromatin formation in Neurospora crassa William K. Storck1, Vincent T. Bicocca1, Michael R. Rountree1, Shinji Honda2, Tereza Ormsby1 and Eric U. Selker 1,* 1Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA and 2Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan Downloaded from https://academic.oup.com/nar/article/48/18/10199/5908534 by guest on 29 September 2021 Received January 15, 2020; Revised August 17, 2020; Editorial Decision August 18, 2020; Accepted September 16, 2020 ABSTRACT INTRODUCTION Heterochromatin is a specialized form of chromatin The basic unit of chromatin, the nucleosome, consists of that restricts access to DNA and inhibits genetic about 146 bp of DNA wrapped around a histone octamer. processes, including transcription and recombina- Histones possess unstructured N-terminal tails that are sub- ject to various post-translational modifications, which re- tion. In Neurospora crassa, constitutive heterochro- / matin is characterized by trimethylation of lysine 9 flect and or influence the transcriptional state of the un- derlying chromatin. Methylation of lysines 4 and 36 of his- on histone H3, hypoacetylation of histones, and DNA tone H3 (H3K4, H3K36), as well as hyperacetylation of hi- methylation. We explored whether the conserved hi- stones, are associated with transcriptionally active euchro- stone demethylase, lysine-specific demethylase 1 matin while methylation of lysines 9 and 27 of histone H3 (LSD1), regulates heterochromatin in Neurospora, (H3K9, H3K27) and hypoacetylation are associated with and if so, how.
    [Show full text]
  • The Hidden Kingdom
    INTRODUCTION Fungi—The Hidden Kingdom OBJECTIVE • To provide students with basic knowledge about fungi Activity 0.1 BACKGROUND INFORMATION The following text provides an introduction to the fungi. It is written with the intention of sparking curiosity about this GRADES fascinating biological kingdom. 4-6 with a K-3 adaptation TEACHER INSTRUCTIONS TYPE OF ACTIVITY 1. With your class, brainstorm everything you know about fungi. Teacher read/comprehension 2. For younger students, hand out the question sheet before you begin the teacher read and have them follow along and MATERIALS answer the questions as you read. • copies of page 11 3. For older students, inform them that they will be given a • pencils brainteaser quiz (that is not for evaluation) after you finish reading the text. VOCABULARY 4. The class can work on the questions with partners or in groups bioremediation and then go over the answers as a class. Discuss any chitin particularly interesting facts and encourage further fungi independent research. habitat hyphae K-3 ADAPTATION kingdom 1. To introduce younger students to fungi, you can make a KWL lichens chart either as a class or individually. A KWL chart is divided moulds into three parts. The first tells what a student KNOWS (K) mushrooms about a subject before it is studied in class. The second part mycelium tells what the student WANTS (W) to know about that subject. mycorrhizas The third part tells what the child LEARNED (L) after studying nematodes that subject. parasitic fungi 2. Share some of the fascinating fungal facts presented in the photosynthesis “Fungi—The Hidden Kingdom” text with your students.
    [Show full text]
  • Fungal Evolution: Major Ecological Adaptations and Evolutionary Transitions
    Biol. Rev. (2019), pp. 000–000. 1 doi: 10.1111/brv.12510 Fungal evolution: major ecological adaptations and evolutionary transitions Miguel A. Naranjo-Ortiz1 and Toni Gabaldon´ 1,2,3∗ 1Department of Genomics and Bioinformatics, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain 2 Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain 3ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain ABSTRACT Fungi are a highly diverse group of heterotrophic eukaryotes characterized by the absence of phagotrophy and the presence of a chitinous cell wall. While unicellular fungi are far from rare, part of the evolutionary success of the group resides in their ability to grow indefinitely as a cylindrical multinucleated cell (hypha). Armed with these morphological traits and with an extremely high metabolical diversity, fungi have conquered numerous ecological niches and have shaped a whole world of interactions with other living organisms. Herein we survey the main evolutionary and ecological processes that have guided fungal diversity. We will first review the ecology and evolution of the zoosporic lineages and the process of terrestrialization, as one of the major evolutionary transitions in this kingdom. Several plausible scenarios have been proposed for fungal terrestralization and we here propose a new scenario, which considers icy environments as a transitory niche between water and emerged land. We then focus on exploring the main ecological relationships of Fungi with other organisms (other fungi, protozoans, animals and plants), as well as the origin of adaptations to certain specialized ecological niches within the group (lichens, black fungi and yeasts).
    [Show full text]
  • Observations on the Behavior of Suppressors In
    VOL . 38, 1952 GENETICS: MITCHELL AND MITCHELL 205 10 Horowitz, N. H., and Beadle, G. W., Ibid., 150, 325-333 (1943). 11 Horowitz, N. H., Bonner, D., and Houlahan, M. B., Ibid., 159, 145-151 (1945). 12 Horowitz, N. H., Ibid., 162, 413-419 (1945). 13 Shive, W., J. Am. Chem. Soc., 69, 725 (1947). 14 Stetten, M. R., and Fox, C. L., J. Biol. Chem., 161, 333 (1945). " Teas, H. J., Thesis, California Institute of Technology (1947). 16 Emerson, S., and Cushing, J. E., Federation Proc., 5, 379-389 (1946). 17 Emerson, S., J. Bact., 54, 195-207 (1947). 18 Zalokar, M., these PROCEEDINGS, 34, 32-36 (1948). '9 Zalokar, M., J. Bact., 60, 191-203 (1950). OBSERVATIONS ON THE BEHA VIOR OF SUPPRESSORS IN NE UROSPORA * By MARY B. MITCHELL AND HERSCHEL K. MlTCHELL KERCKHOFF LABORATORIES OF BIOLOGY, CALIFORNIA INSTITUTE OF TECHNOLOGY, PASADENA, CALIFORNIA Communicated by G. W. Beadle, January 14, 1952 A suppressor of pyrimidineless 3a (37301) and some aspects of the be- havior of the suppressed mutant have been described earlier.' The obser- vation that lysine, omithine, citrulline and arginine influence growth re- sponses of the suppressed mutant suggested studies of the behavior of re- combinants involving pyr 3a and s and mutants having requirements for these amino acids. Effects of the pyrimidineless mutant and its suppressor upon certain lysine-requiring mutants have been reported.2 The present paper deals with a somewhat greater variety of interactions observed be- tween pyr 3a and s and mutants which utilize proline, ornithine, citrulline or arginine.3 These interactions include suppression of two non-allelic prolineless mutants by the pyrimidineless suppressor and partial sup- pression of pyr 3a by three non-allelic omithineless mutants.
    [Show full text]
  • Field Guide to Common Macrofungi in Eastern Forests and Their Ecosystem Functions
    United States Department of Field Guide to Agriculture Common Macrofungi Forest Service in Eastern Forests Northern Research Station and Their Ecosystem General Technical Report NRS-79 Functions Michael E. Ostry Neil A. Anderson Joseph G. O’Brien Cover Photos Front: Morel, Morchella esculenta. Photo by Neil A. Anderson, University of Minnesota. Back: Bear’s Head Tooth, Hericium coralloides. Photo by Michael E. Ostry, U.S. Forest Service. The Authors MICHAEL E. OSTRY, research plant pathologist, U.S. Forest Service, Northern Research Station, St. Paul, MN NEIL A. ANDERSON, professor emeritus, University of Minnesota, Department of Plant Pathology, St. Paul, MN JOSEPH G. O’BRIEN, plant pathologist, U.S. Forest Service, Forest Health Protection, St. Paul, MN Manuscript received for publication 23 April 2010 Published by: For additional copies: U.S. FOREST SERVICE U.S. Forest Service 11 CAMPUS BLVD SUITE 200 Publications Distribution NEWTOWN SQUARE PA 19073 359 Main Road Delaware, OH 43015-8640 April 2011 Fax: (740)368-0152 Visit our homepage at: http://www.nrs.fs.fed.us/ CONTENTS Introduction: About this Guide 1 Mushroom Basics 2 Aspen-Birch Ecosystem Mycorrhizal On the ground associated with tree roots Fly Agaric Amanita muscaria 8 Destroying Angel Amanita virosa, A. verna, A. bisporigera 9 The Omnipresent Laccaria Laccaria bicolor 10 Aspen Bolete Leccinum aurantiacum, L. insigne 11 Birch Bolete Leccinum scabrum 12 Saprophytic Litter and Wood Decay On wood Oyster Mushroom Pleurotus populinus (P. ostreatus) 13 Artist’s Conk Ganoderma applanatum
    [Show full text]
  • Phylogenetic Investigations of Sordariaceae Based on Multiple Gene Sequences and Morphology
    mycological research 110 (2006) 137– 150 available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/mycres Phylogenetic investigations of Sordariaceae based on multiple gene sequences and morphology Lei CAI*, Rajesh JEEWON, Kevin D. HYDE Centre for Research in Fungal Diversity, Department of Ecology & Biodiversity, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, PR China article info abstract Article history: The family Sordariaceae incorporates a number of fungi that are excellent model organisms Received 10 May 2005 for various biological, biochemical, ecological, genetic and evolutionary studies. To deter- Received in revised form mine the evolutionary relationships within this group and their respective phylogenetic 19 August 2005 placements, multiple-gene sequences (partial nuclear 28S ribosomal DNA, nuclear ITS ribo- Accepted 29 September 2005 somal DNA and partial nuclear b-tubulin) were analysed using maximum parsimony and Corresponding Editor: H. Thorsten Bayesian analyses. Analyses of different gene datasets were performed individually and Lumbsch then combined to generate phylogenies. We report that Sordariaceae, with the exclusion Apodus and Diplogelasinospora, is a monophyletic group. Apodus and Diplogelasinospora are Keywords: related to Lasiosphaeriaceae. Multiple gene analyses suggest that the spore sheath is not Ascomycota a phylogenetically significant character to segregate Asordaria from Sordaria. Smooth- Gelasinospora spored Sordaria species (including so-called Asordaria species) constitute a natural group. Neurospora Asordaria is therefore congeneric with Sordaria. Anixiella species nested among Gelasinospora Sordaria species, providing further evidence that non-ostiolate ascomata have evolved from ostio- late ascomata on several independent occasions. This study agrees with previous studies that show heterothallic Neurospora species to be monophyletic, but that homothallic ones may have a multiple origins.
    [Show full text]
  • Perithecial Ascomycetes from the 400 Million Year Old Rhynie Chert: an Example of Ancestral Polymorphism
    Mycologia, 97(1), 2005, pp. 269±285. q 2005 by The Mycological Society of America, Lawrence, KS 66044-8897 Perithecial ascomycetes from the 400 million year old Rhynie chert: an example of ancestral polymorphism Editor's note: Unfortunately, the plates for this article published in the December 2004 issue of Mycologia 96(6):1403±1419 were misprinted. This contribution includes the description of a new genus and a new species. The name of a new taxon of fossil plants must be accompanied by an illustration or ®gure showing the essential characters (ICBN, Art. 38.1). This requirement was not met in the previous printing, and as a result we are publishing the entire paper again to correct the error. We apologize to the authors. T.N. Taylor1 terpreted as the anamorph of the fungus. Conidioge- Department of Ecology and Evolutionary Biology, and nesis is thallic, basipetal and probably of the holoar- Natural History Museum and Biodiversity Research thric-type; arthrospores are cube-shaped. Some peri- Center, University of Kansas, Lawrence, Kansas thecia contain mycoparasites in the form of hyphae 66045 and thick-walled spores of various sizes. The structure H. Hass and morphology of the fossil fungus is compared H. Kerp with modern ascomycetes that produce perithecial as- Forschungsstelle fuÈr PalaÈobotanik, Westfalische cocarps, and characters that de®ne the fungus are Wilhelms-UniversitaÈt MuÈnster, Germany considered in the context of ascomycete phylogeny. M. Krings Key words: anamorph, arthrospores, ascomycete, Bayerische Staatssammlung fuÈr PalaÈontologie und ascospores, conidia, fossil fungi, Lower Devonian, my- Geologie, Richard-Wagner-Straûe 10, 80333 MuÈnchen, coparasite, perithecium, Rhynie chert, teleomorph Germany R.T.
    [Show full text]
  • Protists/Fungi Station Lab Information
    Protists/Fungi Station Lab Information 1 Protists Information Background: Perhaps the most strikingly diverse group of organisms on Earth is that of the Protists, Found almost anywhere there is water – from puddles to sediments. Protists rely on water. Somea re marine (salt water), some are freshwater, some are terrestrial (land dwellers) in moist soil and some are parasites which live in the tissues of others. The Protist kingdom is made up of a wide variety of eukaryotic cells. All protist cells have nuclei and other characteristics eukaryotic features. Some protists have more than one nucleus and are called “multinucleated”. Cellular Organization: Protists show a variety in cellular organization: single celled (unicellular), groups of single cells living together in a close and permanent association (colonies or filaments) or many cells = multicellular organization (ex. Seaweed). Obtaining food: There is a variety in how protists get their food. Like plants, many protists are autotrophs, meaning they make their own food through photosynthesis and store it as starch. It is estimated that green protist cells chemically capture and process over a billion tons of carbon in the Earth’s oceans and freshwater ponds every year. Photosynthetic or “green” protists have a multitude of membrane-enclosed bags (chloroplasts) which contain the photosynthetic green pigment called chlorophyll. Many of these organisms’ cell walls are similar to that of plant cells and are made of cellulose. Others are “heterotrophs”. Like animals, they eat other organisms or, like fungi, receiving their nourishment from absorbing nutrient molecules from their surroundings or digest living things. Some are parasitic and feed off of a living host.
    [Show full text]
  • The Fungal Genetic System: a Historical Overview
    UC Irvine UC Irvine Previously Published Works Title The fungal genetic system: A historical overview Permalink https://escholarship.org/uc/item/31w7q0q0 Journal Journal of Genetics, 75(3) ISSN 0022-1333 Author Davis, Rowland H Publication Date 1996-12-01 DOI 10.1007/BF02966305 Peer reviewed eScholarship.org Powered by the California Digital Library University of California J. Goner., Vol. 75, Number 3, December 1996, pp. 245 - 253. O Indian Academy of Sciences The fungai genetic system: a historical overview ROWLAND H. DAVIS Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA 1. The early years The genetics of filamentous fungi was initiated through the efforts of rather few people, whose work led to the explosive development of the genetics and biochemistry of Neurospora crassa and Aspergitlus nidulans in the 1940s and 1950s. Among the major contributors is David Perkins, whom this issue of Journal of Genetics honours, and who continues to this day to be an international resource of new knowledge about N. crassa. This article is biased towards Neurospora, in keeping with its intent to honour David and with the focus of many of the articles to follow. I have chosen a historical theme, leaving to others the task of illuminating the present. Neurospora became part of a continuous line of organisms underlying the twentieth- century revolution in biology. Many of the interests and traditions of geneticists working with Drosophila, mouse and corn were carried over to N. crassa, together with a new ambition to understand the relationship between genes and enzymes. It is easy for today's student to forget that work on Neurospora genetics and biochemistry preceded the modern development of these areas in Escherichia coli and yeast.
    [Show full text]
  • Biology of Fungi, Lecture 2: the Diversity of Fungi and Fungus-Like Organisms
    Biology of Fungi, Lecture 2: The Diversity of Fungi and Fungus-Like Organisms Terms You Should Understand u ‘Fungus’ (pl., fungi) is a taxonomic term and does not refer to morphology u ‘Mold’ is a morphological term referring to a filamentous (multicellular) condition u ‘Mildew’ is a term that refers to a particular type of mold u ‘Yeast’ is a morphological term referring to a unicellular condition Special Lecture Notes on Fungal Taxonomy u Fungal taxonomy is constantly in flux u Not one taxonomic scheme will be agreed upon by all mycologists u Classical fungal taxonomy was based primarily upon morphological features u Contemporary fungal taxonomy is based upon phylogenetic relationships Fungi in a Broad Sense u Mycologists have traditionally studied a diverse number of organisms, many not true fungi, but fungal-like in their appearance, physiology, or life style u At one point, these fungal-like microbes included the Actinomycetes, due to their filamentous growth patterns, but today are known as Gram-positive bacteria u The types of organisms mycologists have traditionally studied are now divided based upon phylogenetic relationships u These relationships are: Q Kingdom Fungi - true fungi Q Kingdom Straminipila - “water molds” Q Kingdom Mycetozoa - “slime molds” u Kingdom Fungi (Mycota) Q Phylum: Chytridiomycota Q Phylum: Zygomycota Q Phylum: Glomeromycota Q Phylum: Ascomycota Q Phylum: Basidiomycota Q Form-Phylum: Deuteromycota (Fungi Imperfecti) Page 1 of 16 Biology of Fungi Lecture 2: Diversity of Fungi u Kingdom Straminiplia (Chromista)
    [Show full text]
  • 9B Taxonomy to Genus
    Fungus and Lichen Genera in the NEMF Database Taxonomic hierarchy: phyllum > class (-etes) > order (-ales) > family (-ceae) > genus. Total number of genera in the database: 526 Anamorphic fungi (see p. 4), which are disseminated by propagules not formed from cells where meiosis has occurred, are presently not grouped by class, order, etc. Most propagules can be referred to as "conidia," but some are derived from unspecialized vegetative mycelium. A significant number are correlated with fungal states that produce spores derived from cells where meiosis has, or is assumed to have, occurred. These are, where known, members of the ascomycetes or basidiomycetes. However, in many cases, they are still undescribed, unrecognized or poorly known. (Explanation paraphrased from "Dictionary of the Fungi, 9th Edition.") Principal authority for this taxonomy is the Dictionary of the Fungi and its online database, www.indexfungorum.org. For lichens, see Lecanoromycetes on p. 3. Basidiomycota Aegerita Poria Macrolepiota Grandinia Poronidulus Melanophyllum Agaricomycetes Hyphoderma Postia Amanitaceae Cantharellales Meripilaceae Pycnoporellus Amanita Cantharellaceae Abortiporus Skeletocutis Bolbitiaceae Cantharellus Antrodia Trichaptum Agrocybe Craterellus Grifola Tyromyces Bolbitius Clavulinaceae Meripilus Sistotremataceae Conocybe Clavulina Physisporinus Trechispora Hebeloma Hydnaceae Meruliaceae Sparassidaceae Panaeolina Hydnum Climacodon Sparassis Clavariaceae Polyporales Gloeoporus Steccherinaceae Clavaria Albatrellaceae Hyphodermopsis Antrodiella
    [Show full text]
  • Neurospora Tetrasperma from Natural Populations
    Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1084 Neurospora tetrasperma from Natural Populations Toward the Population Genomics of a Model Fungus PÁDRAIC CORCORAN ACTA UNIVERSITATIS UPSALIENSIS ISSN 1651-6214 ISBN 978-91-554-8771-3 UPPSALA urn:nbn:se:uu:diva-208791 2013 Dissertation presented at Uppsala University to be publicly examined in Zootisalen, EBC, Uppsala, Friday, November 22, 2013 at 09:00 for the degree of Doctor of Philosophy. The examination will be conducted in English. Abstract Corcoran, P. 2013. Neurospora tetrasperma from Natural Populations: Toward the Population Genomics of a Model Fungus. Acta Universitatis Upsaliensis. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1084. 52 pp. Uppsala. ISBN 978-91-554-8771-3. The study of DNA sequence variation is a powerful approach to study genome evolution, and to reconstruct evolutionary histories of species. In this thesis, I have studied genetic variation in the fungus Neurospora tetrasperma and other closely related Neurospora species. I have focused on N. tetrasperma in my research because it has large regions of suppressed recombination on its mating-type chromosomes, had undergone a recent change in reproductive mode and is composed of multiple reproductively isolated lineages. Using DNA sequence data from a large sample set representing multiple species of Neurospora I estimated that N. tetrasperma evolved ~1 million years ago and that it is composed of at least 10 lineages. My analysis of the type of asexual spores produced using newly described N. tetrasperma populations in Britain revealed that lineages differ considerably in life history characteristics that may have consequences for their evolution.
    [Show full text]