Genes and Gene Action 2 Course Guide 2019-2020

Total Page:16

File Type:pdf, Size:1020Kb

Genes and Gene Action 2 Course Guide 2019-2020 Genes and Gene Action 2 Course Guide 2019-2020 Course Organiser: Prof.David Finnegan Dr Elizabeth Bayne Course Email: [email protected] Name: ____________________________ If you require this document in an alternative format, such as large print or a coloured background, please contact the Biology Teaching Organisation, University of Edinburgh, James Clerk Maxwell Building, King’s Buildings, Edinburgh or email Carolyn Wilson at [email protected] ASSESSMENT DEADLINES AND FEEDBACK Assessment Available Due Feedback % of % of ICA Course mark mark Course Problem Jan 24th Feb 17th - noon Tutorial 3 12.5% 5% Lecture Quiz 1 Jan 21st - 11am Jan 28th - 11am Quiz 2 Jan 28th - 11am Feb 4th - 11am Quiz 3 Feb 4th -11am Feb 11th -11am Quiz 4 Feb 11th - 11am Feb 25th - 11am On Quiz 5 Feb 25th -11am Mar 3rd -11am submission 25% 10% Quiz 6 Mar 3rd - 11am Mar 10th -11am Quiz 7 Mar 10th -11am Mar 17th -11am Quiz 8 Mar 17th -11am Mar 24th - 11am Quiz 9 Mar 24th - 11am Mar 31st -11am PeerWise Jan 17th Day of Exam After exam 12.5% 5% Data Handling April 1 April 1 On 50% 20% Test Submission The semester 2 exam diet will run from Monday 27th April 2020 to Friday 22nd May 2020. Exam dates will be published on Monday 2nd March 2020. Who to contact if you... If you don’t know what tutorial or practical group you are in Need timetable information then check your online timetable or Learn If you still need help, ask at BTO reception. *Complete the Group Change Request form at https://www.edweb.ed.ac.uk/timetabling- examinations/timetabling/personalised-timetables/group- change-request Have a timetable clash *Please note that due to the high number of students enrolled on the course this year it may not be possible to move you to your chosen group and you may be asked to arrange to swap groups with a fellow student. Need general GGA2 information Email the course secretary: [email protected] No need to contact anyone. Check the Learn site as lecture Have missed a lecture notes and recordings are uploaded regularly. If possible speak to others who have attended and make sure that you understand any problems and solutions that Have missed a practical or tutorial have been discussed. Should any points of difficulty remain you should seek clarification from your tutor or practical leader Contact your Personal Tutor or Student Support Tutors. For Have health or personal problems details see ‘Special Circumstances’ section of the “Essential Information for Biological Science Students” Need academic advice about the Contact the Course Organiser: [email protected] course: Have a question about a specific Email the relevant Lecturer. lecture Student intranet: https://www.wiki.ed.ac.uk/display/SBSUndergraduateIntranet/School+of+Biological+Scienc es+Undergraduate+Students%27+Intranet 1 GENES AND GENE ACTION 2019 - 2020 CONTENTS Assessment deadlines 1 Aims of Course 3 Learning Objectives 3 Graduate Attributes 3 Timetable 5 Teaching Staff 6 Recommended Textbooks 7 Course discussion board 7 Structure of the Course 7 Synopsis of Lectures 8 Lecture “flipping” 10 Organisation of Practical and Tutorial Groups 11 Schedule of Practicals and Tutorials 12 Lab and Tutorial records 13 Assessment 14 PeerWise 14 Course Problem 14 Data Handling Test 15 Exam 15 Common Marking Scheme 17 Feedback (to you and from you) 18 FAQ 19 Tutorial 1 21 Tutorial 2 23 Tutorial 3 25 Tutorial 4 26 Synopsis of Practicals 29 Practical Schedule 31 Practical 1 32 Practical 2 36 Practical 3 46 Practical 4 55 Practical 5 59 Further Information 65 2 GENES AND GENE ACTION 2 2019-2020 This guide should be used in conjunction with information and learning support material available on Learn. AIMS OF THE COURSE The course aims to provide an introduction to modern genetics to prepare students for third year courses. This is achieved through an integrated series of lectures, practicals and tutorials designed to give an appreciation of the systems and methods used for classical genetic and molecular genetic analysis. LEARNING OUTCOMES As a result of successfully completing this course you should: 1] be able to explain how genetics is used to analyse a variety of biological phenomena. 2] be able to carry out genetic experiments and to analyse and interpret the results of these experiments. 3] be able to solve genetic problems related to the topics covered during the course 4] be able to use collaborative learning to develop your personal effectiveness. DEVELOPMENT OF “GRADUATE ATTRIBUTES’ The University has identified a set of four clusters of skills and abilities that students should develop throughout their degree programme to strengthen your attitude towards lifelong learning and personal development, as well as future employability. The graduate attributes we hope to develop with the Genes and Gene Action 2 course are indicated below. Research and Enquiry This course aims to increase your understanding of classic, modern and molecular genetics and also your problem solving skills. The knowledge obtained, and the development of research and technical skills, will be of benefit to you during the rest of your degree and beyond. The course will develop your research and problem solving capabilities through your work on the course problem and the data handling test, and the feedback that you will obtain from these tasks. Staff will assist you to learn and practice problem-solving skills during tutorials and practicals throughout the course. Personal and Intellectual Autonomy You are expected to take responsibility for your own learning and to work independently to meet the challenges of the course. You are expected to explore textbooks, and occasionally research papers, not only to expand your knowledge of the topics covered in the lectures, but to broaden your understanding of areas of genetics that interest you. You are encouraged to discuss the course problem and questions in the tutorials and practicals with other students but answers that you submit must be entirely your own work. You are also responsible for making your own record of practical and tutorial exercises. These are integral part of the course and will help you when preparing for both the data handling test and the degree exam while peer marking of the course problem will develop your ability to assess the ideas of others. 3 Communication Through discussion and collaboration with students in practical and tutorial groups you will be able to communicate your views and ideas and to learn from your peers. Genes and Gene Action has an active Learn discussion board and you can benefit greatly from participating. You are also required, as part of the course assessment, to engage in peer marking, and to use the online PeerWise system to share and discuss course related questions. The opportunities to benefit academically from such communications are proven and considerable. Personal Effectiveness Throughout your degree programme you will learn transferable skills that will benefit you not only across the courses you are enrolled in, but in future employment and further study. In this course, as in others, time management is an important skill that you will learn as you develop ways to organise your work and meet deadlines. Effective participation in the Peer wise exercise, for example, requires that you submit your questions reasonably early in the course in order to allow others to answer, comment and discuss your questions with you. Working effectively as a member of a group is an important transferable skill. This will be enhanced by collaborating with other students in tutorials and practicals. This will help you become aware of your skills and talents (and possibly your limitations) and to develop your own scientific style. 4 TIMETABLE Week Date Lectures and Quectures Practicals Tutorials Quizzes Title Lecturer # Groups Tutors Start End 14-Jan 1: Introduction – DF DF – – – – 1 15-Jan – – Practical 1 – Group 1 (am); Group 2 (pm) – – – 16-Jan 2: Recombination and Maps 1 DF – – – – 17-Jan 3: Recombination and Maps 2 DF – – – – 21-Jan 4: Recombination and Maps 3 DF – – – Quiz 1 – 2 22-Jan – – Practical 1 – Group 3 (am) 1 A to F HW, HM, AD, JG, DF, VM 23-Jan 5: Thinking about Genes DF Practical 1 – Group 4 (pm) 1 G, H & Q HW, KH, JS 24-Jan 6: Mendelian Genetic Analysis HM – – – 28-Jan 7: Chromosome Structure HM 1 S DF Quiz 2 Quiz 1 3 29-Jan – – Practical 2 – Group 1 (am); Group 2 (pm) 1 I to N HW, HM, AD, JG, DF, VM 30-Jan 8: Eukaryotic Genes and Genomes HM – 1 O, P & R HW, KH, JS 31-Jan 9: Genetic Interactions HM – – – – 04-Feb 10: DNA Replication MeK – – – – Quiz 3 Quiz 2 4 05-Feb – – Practical 2 – Group 3 (am) 2 A to F HW, HM, AD, JG, DF, VM 06-Feb 11: Mutation, Mutagenesis and Repair MeK Practical 2 – Group 4 (pm) 2 G, H & Q HW, KH, JS 07-Feb 12: Gene Expression: Transcription and Translation MeK – – – – 11-Feb 13: The Prokaryotic Gene: structure and regulation MeK – 2 S DF Quiz 4 Quiz 3 5 12-Feb – – Practical 3 – Group 1 (am); Group 2 (pm) 2 I to N HW, HM, AD, JG, DF, VM 13-Feb 14: The Genetic Code and Consequencs of Mutation MeK – 2 O, P & R HW, KH, JS 14-Feb 15: Plasmids DL – – – – 18-Feb No quiz – 19-Feb 20-Feb Flexible Learning Week 21-Feb 25-Feb 16: Bacterial Transpsons DL – – – Quiz 5 Quiz 4 6 26-Feb – – Practical 3 – Group 3 (am) 3 A to F HW, HM, AD, JG, DF, VM 27-Feb 17: Conjugation DL Practical 3 – Group 4 (pm) 3 G, H & Q HW, KH, JS 28-Feb 18: Transduction and Transformation DL – – – 03-Mar 19: Mid-semester feedback and Revision Session DF, MeK, DL HM – 3 S DF Quiz 6 Quiz 5 7 04-Mar – – Practical 4 – Group 1 (am); Group 2(pm) 3 I to
Recommended publications
  • Human Cell Assays for Synthesis-Dependent Strand Annealing and Crossing Over During Double-Strand Break Repair
    INVESTIGATIONS Human Cell Assays for Synthesis-Dependent Strand Annealing and Crossing Over During Double-Strand Break Repair Grzegorz Zapotoczny∗,1 and Jeff Sekelsky∗ † ‡,1 ∗Curriculum in Genetics and Molecular Biology, †Department of Biology, ‡Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA ABSTRACT DNA double-strand breaks (DSBs) are one of the most deleterious types of lesions to the genome. KEYWORDS Synthesis-dependent strand annealing (SDSA) is thought to be a major pathway of DSB repair, but direct tests double-strand of this model have only been conducted in budding yeast and Drosophila. To better understand this pathway, break repair we developed an SDSA assay for use in human cells. Our results support the hypothesis that SDSA is an crossing over important DSB repair mechanism in human cells. We used siRNA knockdown to assess the roles of a number synthesis- of helicases suggested to promote SDSA. None of the helicase knockdowns reduced SDSA, but knocking dependent down BLM or RTEL1 increased SDSA. Molecular analysis of repair products suggest that these helicases may strand annealing prevent long-tract repair synthesis. Since the major alternative to SDSA – repair involving a double-Holliday junction intermediate – can lead to crossovers, we also developed a fluorescent assay that detects crossovers generated during DSB repair. Together, these assays will be useful in investigating features and mechanisms of SDSA and crossover pathways in human cells. link (Figure1)(Thaler et al. 1987); this process has been called INTRODUCTION dissolution to distinguish it from endonucleolytic resolution (Wu and Hickson 2003).
    [Show full text]
  • Perspectives
    Copyright Ó 2008 by the Genetics Society of America Perspectives Anecdotal, Historical and Critical Commentaries on Genetics Edited by James F. Crow and William F. Dove The Phage Mating Theory, With Lessons for Yeast Geneticists Frank Stahl1 Institute of Molecular Biology, University of Oregon, Eugene, Oregon 97403-1229 HEN physicist Max Delbru¨ck undertook the study sistance to the possibility of genetic recombination with W of phage growth (Ellis and Delbru¨ck 1939), he its implications of sexual reproduction and the variety of anticipated that phage would be the best model for highly evolved stuff that so often goes with it (Delbru¨ck elucidating biological reproduction and mutation, un- and Bailey 1947). complicated by sex (Delbru¨ck 1970). This Perspectives However, Max’s hopes for simplicity were soon chal- traces Max’s attempt to come to grips with realities that lenged again by the results and interpretation of experi- threatened that view, and it considers present-day rel- ments conducted with UV-inactivated phages (Luria evanceforyeastgeneticistsoftwolessonsthatremainfrom 1947; Luria and Dulbecco 1949). The UV experiments his heroic effort. showed that phage particles killed by irradiation could Readers should understand (or recall) that in 1939 cooperate to produce live phage, a trick that was labeled essentially nothing of what we now know about the ‘‘multiplicity reactivation’’ (MR) because this cooper- chemistry of either reproduction or mutation was even ation required that a bacterial cell be infected with two imagined—for nucleic acids, it was ‘‘known’’ only that or more phage particles. Luria and Dulbecco (1949) most of the DNA is in the nucleus and most of the RNA is collected MR data for a range of UV doses and a variety of in the cytoplasm and, for proteins, only that some were multiplicities and found that the data could be fitted to a enzymes and that they were probably the stuff that genes mathematically expressed theory.
    [Show full text]
  • Meiotic Recombination and Its Implications for Plant Breeding
    Meiotic recombination and its implications for plant breeding T.G. (Erik) Wijnker Thesis committee Promotors Prof. dr. J.H.S.G.M. de Jong Personal chair at the Laboratory of Genetics, Wageningen University Prof. dr. ir. M. Koornneef Personal chair at the Laboratory of Genetics, Wageningen University and Director at the Max Planck Institute for Plant Breeding Research (MPIZ) Cologne, Germany Co-promotor Dr. R.H.G. Dirks Research manager at the Rijk Zwaan Breeding Company, Fijnaart. Other members Prof. dr. ir. E. Jacobsen, Wageningen University, Wageningen Prof. dr. H. Puchta, University of Karlsruhe, Karlsruhe, Germany Dr. A. Schnittger, University of Strasbourg, Strasbourg, France Prof. dr. M.E. Schranz, Wageningen University, Wageningen This research was conducted under the auspices of the Graduate School Experimental Plant Sciences (EPS) Meiotic recombination and its implications for plant breeding T.G. (Erik) Wijnker Thesis at Wageningen University Submitted in fulfillment of the requirements for the degree of doctor Prof. dr. M.J. Kropf, by the authorityin the presence of the Rector of the Magnificus Thesis Committee appointed by the Academic Board to be defended in public on Wednesday 6 February 2013 at 4 p.m. in the Aula. T.G. (Erik) Wijnker Meiotic Recombination and its implications for plant breeding With references, with summaries in Dutch and English Thesis, Wageningen University, Wageningen, NL (2013) ISBN 978-94-6173-440-2 Contents General introduction Chapter 1 7 Whole-genome sequencing of (non–)crossover sites reveals that
    [Show full text]
  • Insights Into Regulation of Human RAD51 Nucleoprotein Filament Activity During
    Insights into Regulation of Human RAD51 Nucleoprotein Filament Activity During Homologous Recombination Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Ravindra Bandara Amunugama, B.S. Biophysics Graduate Program The Ohio State University 2011 Dissertation Committee: Richard Fishel PhD, Advisor Jeffrey Parvin MD PhD Charles Bell PhD Michael Poirier PhD Copyright by Ravindra Bandara Amunugama 2011 ABSTRACT Homologous recombination (HR) is a mechanistically conserved pathway that occurs during meiosis and following the formation of DNA double strand breaks (DSBs) induced by exogenous stresses such as ionization radiation. HR is also involved in restoring replication when replication forks have stalled or collapsed. Defective recombination machinery leads to chromosomal instability and predisposition to tumorigenesis. However, unregulated HR repair system also leads to similar outcomes. Fortunately, eukaryotes have evolved elegant HR repair machinery with multiple mediators and regulatory inputs that largely ensures an appropriate outcome. A fundamental step in HR is the homology search and strand exchange catalyzed by the RAD51 recombinase. This process requires the formation of a nucleoprotein filament (NPF) on single-strand DNA (ssDNA). In Chapter 2 of this dissertation I describe work on identification of two residues of human RAD51 (HsRAD51) subunit interface, F129 in the Walker A box and H294 of the L2 ssDNA binding region that are essential residues for salt-induced recombinase activity. Mutation of F129 or H294 leads to loss or reduced DNA induced ATPase activity and formation of a non-functional NPF that eliminates recombinase activity. DNA binding studies indicate that these residues may be essential for sensing the ATP nucleotide for a functional NPF formation.
    [Show full text]
  • Branching Out: Meiotic Recombination and Its Regulation
    TICB-453; No of Pages 8 Review TRENDS in Cell Biology Vol.xxx No.x Branching out: meiotic recombination and its regulation Gareth A. Cromie and Gerald R. Smith Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109-1024, USA Homologous recombination is a dynamic process by parental chromosome segregation during the first meiotic which DNA sequences and strands are exchanged. In division. The COs link the homologous chromosomes phy- meiosis, the reciprocal DNA recombination events called sically so that they can be oriented correctly on the meiotic crossovers are central to the generation of genetic diver- spindle. In the absence of COs, chromosomes often mis- sity in gametes and are required for homolog segregation segregate, resulting in aneuploid gametes and offspring. in most organisms. Recent studies have shed light on how Recent studies have advanced our understanding of how meiotic crossovers and other recombination products meiotic COs and NCOs form, how they are distributed form, how their position and number are regulated and across genomes, and how the pair of DNA molecules under- how the DNA molecules undergoing recombination are going a CO is chosen. In this review, we focus on how chosen. These studies indicate that the long-dominant, advances in these three areas have challenged several core unifying model of recombination proposed by Szostak features of long-accepted models, revealing many new et al. applies, with modification, only to a subset of branches of the meiotic recombination ‘pathway’. Most recombination events. Instead, crossover formation and significantly, the mechanism of recombination associated its control involve multiple pathways, with considerable with the well-known DSB repair model of Szostak et al.
    [Show full text]
  • The Choice in Meiosis – Defining the Factors That Influence Crossover Or Non-Crossover Formation
    Commentary 501 The choice in meiosis – defining the factors that influence crossover or non-crossover formation Jillian L. Youds and Simon J. Boulton* DNA Damage Response Laboratory, Cancer Research UK, London Research Institute, Clare Hall, Blanche Lane, South Mimms EN6 3LD, UK *Author for correspondence ([email protected]) Journal of Cell Science 124, 501-513 © 2011. Published by The Company of Biologists Ltd doi:10.1242/jcs.074427 Summary Meiotic crossovers are essential for ensuring correct chromosome segregation as well as for creating new combinations of alleles for natural selection to take place. During meiosis, excess meiotic double-strand breaks (DSBs) are generated; a subset of these breaks are repaired to form crossovers, whereas the remainder are repaired as non-crossovers. What determines where meiotic DSBs are created and whether a crossover or non-crossover will be formed at any particular DSB remains largely unclear. Nevertheless, several recent papers have revealed important insights into the factors that control the decision between crossover and non-crossover formation in meiosis, including DNA elements that determine the positioning of meiotic DSBs, and the generation and processing of recombination intermediates. In this review, we focus on the factors that influence DSB positioning, the proteins required for the formation of recombination intermediates and how the processing of these structures generates either a crossover or non-crossover in various organisms. A discussion of crossover interference, assurance and homeostasis, which influence crossing over on a chromosome-wide and genome-wide scale – in addition to current models for the generation of interference – is also included. This Commentary aims to highlight recent advances in our understanding of the factors that promote or prevent meiotic crossing over.
    [Show full text]
  • Repression of Harmful Meiotic Recombination in Centromeric Regions
    Seminars in Cell & Developmental Biology 54 (2016) 188–197 Contents lists available at ScienceDirect Seminars in Cell & Developmental Biology j ournal homepage: www.elsevier.com/locate/semcdb Review Repression of harmful meiotic recombination in centromeric regions ∗ Mridula Nambiar, Gerald R. Smith Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA, United States a r t i c l e i n f o a b s t r a c t Article history: During the first division of meiosis, segregation of homologous chromosomes reduces the chromosome Received 23 November 2015 number by half. In most species, sister chromatid cohesion and reciprocal recombination (crossing-over) Accepted 27 January 2016 between homologous chromosomes are essential to provide tension to signal proper chromosome segre- Available online 3 February 2016 gation during the first meiotic division. Crossovers are not distributed uniformly throughout the genome and are repressed at and near the centromeres. Rare crossovers that occur too near or in the centromere Keywords: interfere with proper segregation and can give rise to aneuploid progeny, which can be severely defec- Meiosis tive or inviable. We review here how crossing-over occurs and how it is prevented in and around the Homologous recombination Crossing-over centromeres. Molecular mechanisms of centromeric repression are only now being elucidated. How- Centromeres ever, rapid advances in understanding crossing-over, chromosome structure, and centromere functions Chromosome segregation promise to explain how potentially deleterious crossovers are avoided in certain chromosomal regions Aneuploidy while allowing beneficial crossovers in others. © 2016 Elsevier Ltd. All rights reserved. Contents 1.
    [Show full text]
  • A Role for DNA Polymerase in Gene Conversion and Crossing Over
    Copyright 2004 by the Genetics Society of America DOI: 10.1534/genetics.104.026260 A Role for DNA Polymerase ␦ in Gene Conversion and Crossing Over During Meiosis in Saccharomyces cerevisiae Laurent Maloisel,*,1 Jaya Bhargava†,2 and G. Shirleen Roeder*,†,‡,3 *Howard Hughes Medical Institute, †Department of Molecular, Cellular and Developmental Biology and ‡Department of Genetics, Yale University, New Haven, Connecticut 06520-8103 Manuscript received January 6, 2004 Accepted for publication April 15, 2004 ABSTRACT A screen for mutants of budding yeast defective in meiotic gene conversion identified a novel allele of the POL3 gene. POL3 encodes the catalytic subunit of DNA polymerase ␦, an essential DNA polymerase involved in genomic DNA replication. The new allele, pol3-ct, specifies a protein missing the last four amino acids. pol3-ct shows little or no defect in DNA replication, but displays a reduction in the length of meiotic gene conversion tracts and a decrease in crossing over. We propose a model in which DNA synthesis determines the length of strand exchange intermediates and influences their resolution toward crossing over. OMOLOGOUS recombination plays a critical role parental origin. If the two parental duplexes are geneti- H in maintaining genome integrity throughout cell cally different within the region of strand exchange, the division. In meiosis, homologous recombination is es- resulting hDNA contains mismatched base pairs and is sential for proper homolog pairing and for the correct referred to as heteroduplex DNA. segregation of chromosomes at the first meiotic division. Single-end invasion intermediates can be channeled In vegetative cells, recombination plays an important toward either of two repair pathways.
    [Show full text]
  • INVESTIGATION of CHROMOSOME SIZE EFFECT on the RATE of CROSSOVERS in the MEIOTIC YEAST Saccharomyces Cerevisiae
    INVESTIGATION OF CHROMOSOME SIZE EFFECT ON THE RATE OF CROSSOVERS IN THE MEIOTIC YEAST Saccharomyces cerevisiae A Thesis presented to the Faculty of California Polytechnic State University, San Luis Obispo In Partial Fulfillment of the Requirements for the Degree Master of Science in Biological Sciences by Lanie Galland June 2014 © 2014 Lanie Maria Galland ALL RIGHTS RESERVED ii COMMITTEE MEMBERSHIP TITLE: Investigation of chromosome size effect on the rate of crossovers in the meiotic yeast Saccharomyces cerevisiae AUTHOR: Lanie Maria Galland DATE SUBMITTED: June 2014 COMMITTEE CHAIR: Kenneth Hillers, PhD Associate Professor of Biological Sciences COMMITTEE MEMBER: Michael Black, PhD Professor of Biological Sciences COMMITTEE MEMBER: Christopher Kitts, PhD Professor and Department Chair of Biological Sciences iii ABSTRACT Investigation of chromosome size effect on the rate of crossovers in the meiotic yeast Saccharomyces cerevisiae Lanie Maria Galland Meiosis is a specialized type of cell division characterized by a single round of DNA replication and two rounds of chromosome segregation, ultimately resulting in four haploid cells. During meiosis I, chromosomes align and reciprocal recombination results in the formation of a crossover, creating the tension required to properly segregate homologs during the first round of meiosis. Two mechanisms involved in regulating the occurrence of crossing over are assurance and interference. Crossover assurance describes the phenomenon that at least one crossover will form between each pair of homologous chromosomes during prophase I. Crossover interference, on the other hand, describes the nonrandom placement of crossovers between homologs, increasing the probability that a second crossover will occur at a discrete distance away from the first one.
    [Show full text]
  • Investigating the Roles of NDJ1 and TID1 in Crossover Assurance in Saccharomyces Cerevisiae
    Investigating the roles of NDJ1 and TID1 in crossover assurance in Saccharomyces cerevisiae A Thesis presented to the Faculty of California Polytechnic State University, San Luis Obispo In Partial Fulfillment of the Requirements for the Degree Master of Science in Biological Sciences by Rianna Knowles November 2011 © 2011 Rianna Lacour Knowles ALL RIGHTS RESERVED ii COMMITTEE MEMBERSHIP TITLE: Investigating the roles of NDJ1 and TID1 in crossover assurance in Saccharomyces cerevisiae AUTHOR: Rianna Knowles DATE SUBMITTED: November 2011 COMMITTEE CHAIR: Dr. Kenneth Hillers, Associate Professor COMMITTEE MEMBER: Dr. Michael Black, Professor COMMITTEE MEMBER: Dr. Elena Keeling, Professor COMMITTEE MEMBER: Dr. Christopher Kitts, Professor and Department Chair iii ABSTRACT Investigating the roles of NDJ1 and TID1 in crossover assurance in Saccharomyces cerevisiae Rianna Knowles Meiosis is the specialized process of cell division utilized during gametogenesis in all sexually reproducing eukaryotes, which consists of one round of DNA replication followed by two rounds of chromosome segregation and results in four haploid cells. Crossovers between homologous chromosomes promote proper alignment and segregation of chromosomes during meiosis. Crossover interference is a genetic phenomenon in which crossovers are non- randomly placed along chromosomes. Crossover assurance ensures that every homologous chromosome pair obtains at least one crossover during Prophase I. Crossovers physically connect homologous pairs, allowing spindle fibers to attach and separate homologs properly. However, some organisms have shown an ability to segregate chromosomes that fail to receive at least one crossover, a phenomenon termed distributive disjunction. In Saccharomyces cerevisiae , mutation of either Tid1 or Ndj1 results in a similar defect in crossover interference. The overall number of crossovers is not substantially different from the wild type, however they are distributed more randomly with respect to each other.
    [Show full text]
  • Whole Genome Approaches to Identify Genes Involved in Early Meiosis
    ! "! ! ! # $ % "& ! "! '" ( ( " #" '!! $&" %" !'!( & ) *++, " - '# . - " . . $ " ./ 0 " !# ./ 1" .. & 2 M- 2 22 M 2 222 M%& ! 2 22* M"# !" ! 0 && 4 225 M 6 227 M & , 2* M" 8 2*2 M ! "#8 2** M 8 2*5 M !""&"&"!&" & 2+ 2*52 M "" 9&"! ! 22 2*7 M& # 27 2*4 M 24 2*42 M !2, 2*6 M: # *2 2*62 M;$) *2 2*6* M:) :) *2 25 M: " !*5 & * M& & ! ! # & ! "& *4 *2 M ! *4 ** M "! !*6 **2 M$ ! *< **22 M: *< **2* M *< *** M( = " ! " ! & *, **5 M& 9& &"#*, *5 M: " *8 *52 M$ " ! & *8 *5* M& 9& &"#5* *7 M$7+ *72 M$ " 7+ *7* M& 9& &"#7* & 5M 9& " !&# 9&"! ! 77 & 5 !! !M " ""; #" ! & 74 52 M ! 74 5* M "! !76 5*2 M !! 76 5** M% ! #!&" 7< 5*5 M:! " ""#!!#& 7, 5*7 M #! !#& 78 55 M: " 78 57 M$45 & 7 M' ""46 72 M ! 46 7* M "! !4< 7*2 M1 &" 4< 7*22 M;:) &! 4< 7*2* M ! " %*64, 7** M%" "!# ! 4, 7*5 M! & # &" #%:48 7*52 M! & 2!* # &" 48 7*7 M( ##!"" " 6+ 7*4 M>9& " ! &" 6+ 7*42 M:) 9 $) !?;%:62 7*6 M' " " 6* 7*62 M " " &" & "#6* 7*6* M "&"" " ! ! 0#!6* 7*< M & "#! &# 0#!65 7*<2 M' "# # & 67 / 7*<22 M'9 "67 7*<2* M( # & 67 7*<* M"" !9 " ! " ##&& ! 64 7*<5 M> !!# &""! &! ! "& 66 7*<7 M 6< 7*<4 M 6< 7*<6 M &!# & #6, 75 M: " 68 752 M " 2# 68 7522 M1 & " 68 752* M2# ! ! ! & " " " "!; & <2 75* M " *# <* 75*2 M1 & " <5 75** M &" !&" ! !" " " <7 75**2 M " &" & "# <7 75*** M%"" " ! ! ! 0#!<6
    [Show full text]
  • Synthesis-Dependent Strand Annealing in Meiosis
    PLoS BIOLOGY Synthesis-Dependent Strand Annealing in Meiosis Melissa S. McMahill1,2, Caroline W. Sham2, Douglas K. Bishop1,2,3* 1 Committee on Genetics, University of Chicago, Chicago, Illinois, United States of America, 2 Department of Radiation and Cellular Oncology, University of Chicago, Chicago, Illinois, United States of America, 3 Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois, United States of America Recent studies led to the proposal that meiotic gene conversion can result after transient engagement of the donor chromatid and subsequent DNA synthesis-dependent strand annealing (SDSA). Double Holliday junction (dHJ) intermediates were previously proposed to form both reciprocal crossover recombinants (COs) and noncrossover recombinants (NCOs); however, dHJs are now thought to give rise mainly to COs, with SDSA forming most or all NCOs. To test this model in Saccharomyces cerevisiae, we constructed a random spore system in which it is possible to identify a subset of NCO recombinants that can readily be accounted for by SDSA, but not by dHJ-mediated recombination. The diagnostic class of recombinants is one in which two markers on opposite sides of a double-strand break site are converted, without conversion of an intervening heterologous insertion located on the donor chromatid. This diagnostic class represents 26% of selected NCO recombinants. Tetrad analysis using the same markers provided additional evidence that SDSA is a major pathway for NCO gene conversion in meiosis. Citation: McMahill MS, Sham CW, Bishop DK (2007) Synthesis-dependent strand annealing in meiosis. PLoS Biol 5(11): e299. doi:10.1371/journal.pbio.0050299 Introduction Tetrad analysis in fungi showed that gene conversion of a marker is frequently associated with reciprocal exchange of Homologous recombination is essential for meiosis, the flanking markers [3,4].
    [Show full text]