1
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Beichman AC, Zhu L, Harris K. The Evolutionary Interplay of Somatic and Germline Mutation Rates. Annu Rev Biomed Data Sci 2024; 7:83-105. [PMID: 38669515 DOI: 10.1146/annurev-biodatasci-102523-104225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2024]
Abstract
Novel sequencing technologies are making it increasingly possible to measure the mutation rates of somatic cell lineages. Accurate germline mutation rate measurement technologies have also been available for a decade, making it possible to assess how this fundamental evolutionary parameter varies across the tree of life. Here, we review some classical theories about germline and somatic mutation rate evolution that were formulated using principles of population genetics and the biology of aging and cancer. We find that somatic mutation rate measurements, while still limited in phylogenetic diversity, seem consistent with the theory that selection to preserve the soma is proportional to life span. However, germline and somatic theories make conflicting predictions regarding which species should have the most accurate DNA repair. Resolving this conflict will require carefully measuring how mutation rates scale with time and cell division and achieving a better understanding of mutation rate pleiotropy among cell types.
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Affiliation(s)
- Annabel C Beichman
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA;
| | - Luke Zhu
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Kelley Harris
- Computational Biology Division, Fred Hutchinson Cancer Center, Seattle, Washington, USA
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA;
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2
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Armstrong JO, Jiang P, Tsai S, Phan MMN, Harris K, Dunham MJ. URA6 mutations provide an alternative mechanism for 5-FOA resistance in Saccharomyces cerevisiae. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.03.597250. [PMID: 38895202 PMCID: PMC11185726 DOI: 10.1101/2024.06.03.597250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
URA3 is frequently used in the yeast community as the mutation target for 5-fluoroorotic acid (5-FOA) resistance. We identified a novel class of ura6 mutants that can grow in the presence of 5-FOA. Unlike ura3 mutants, ura6 mutants remain prototrophic and grow in the absence of uracil. In addition to 5-FOA resistance, we found that mutations to URA6 also confer resistance to 5-fluorocytosine (5-FC) and 5-fluorouracil (5-FU). In total, we identified 50 unique missense mutations across 32 residues of URA6. We found that 28 out of the 32 affected residues are located in regions conserved between Saccharomyces cerevisiae and three clinically relevant pathogenic fungi. These findings suggest that mutations to URA6 present a second target for mutation screens utilizing 5-FOA as a selection marker as well as a potential mode of resistance to the antifungal therapeutic 5-FC.
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Affiliation(s)
| | - Pengyao Jiang
- Department of Genome Sciences, University of Washington
- Center for Mechanisms of Evolution, Biodesign Institute, School of Life Sciences, Arizona State University
| | - Skyler Tsai
- Department of Genome Sciences, University of Washington
| | | | - Kelley Harris
- Department of Genome Sciences, University of Washington
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3
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Gifford DR, Bhattacharyya A, Geim A, Marshall E, Krašovec R, Knight CG. Environmental and genetic influence on the rate and spectrum of spontaneous mutations in Escherichia coli. MICROBIOLOGY (READING, ENGLAND) 2024; 170:001452. [PMID: 38687010 PMCID: PMC11084559 DOI: 10.1099/mic.0.001452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 03/19/2024] [Indexed: 05/02/2024]
Abstract
Spontaneous mutations are the ultimate source of novel genetic variation on which evolution operates. Although mutation rate is often discussed as a single parameter in evolution, it comprises multiple distinct types of changes at the level of DNA. Moreover, the rates of these distinct changes can be independently influenced by genomic background and environmental conditions. Using fluctuation tests, we characterized the spectrum of spontaneous mutations in Escherichia coli grown in low and high glucose environments. These conditions are known to affect the rate of spontaneous mutation in wild-type MG1655, but not in a ΔluxS deletant strain - a gene with roles in both quorum sensing and the recycling of methylation products used in E. coli's DNA repair process. We find an increase in AT>GC transitions in the low glucose environment, suggesting that processes relating to the production or repair of this mutation could drive the response of overall mutation rate to glucose concentration. Interestingly, this increase in AT>GC transitions is maintained by the glucose non-responsive ΔluxS deletant. Instead, an elevated rate of GC>TA transversions, more common in a high glucose environment, leads to a net non-responsiveness of overall mutation rate for this strain. Our results show how relatively subtle changes, such as the concentration of a carbon substrate or loss of a regulatory gene, can substantially influence the amount and nature of genetic variation available to selection.
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Affiliation(s)
- Danna R. Gifford
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Anish Bhattacharyya
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Alexandra Geim
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
- Pembroke College, University of Cambridge, Cambridge, UK
| | - Eleanor Marshall
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Rok Krašovec
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Christopher G. Knight
- Department of Earth and Environmental Sciences, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, Manchester, UK
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4
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Lyu XH, Suo F, Li W, Jia GS, Yang YS, Du LL. Diverse modes of chromosome terminal deletion in spontaneous canavanine-resistant Schizosaccharomyces pombe mutants. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001132. [PMID: 38404922 PMCID: PMC10884838 DOI: 10.17912/micropub.biology.001132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 02/03/2024] [Accepted: 02/02/2024] [Indexed: 02/27/2024]
Abstract
Canavanine resistance has been used to analyze mutation rates in the fission yeast Schizosaccharomyces pombe . However, the genetic basis of canavanine resistance in this organism remains incompletely understood. Here, we performed whole genome sequencing on five spontaneously arising canavanine-resistant S. pombe mutants, including the can2-1 mutant isolated in the 1970s. This analysis revealed that three mutants, including can2-1 , experienced terminal deletions of the left arm of chromosome II, leading to the loss of multiple amino acid transporter genes. Interestingly, these three mutants underwent chromosome terminal deletion through distinct mechanisms, including homology-driven translocation, homology-independent chromosome fusion, and de novo telomere addition. Our findings shed new light on the genetic basis of canavanine resistance and mechanisms underlying chromosome terminal deletions in fission yeast.
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Affiliation(s)
- Xiao-Hui Lyu
- National Institute of Biological Sciences, Beijing, China
| | - Fang Suo
- National Institute of Biological Sciences, Beijing, China
| | - Wen Li
- National Institute of Biological Sciences, Beijing, China
| | - Guo-Song Jia
- National Institute of Biological Sciences, Beijing, China
| | - Yu-Sheng Yang
- National Institute of Biological Sciences, Beijing, China
| | - Li-Lin Du
- National Institute of Biological Sciences, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China
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5
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Li J, Stenberg S, Yue JX, Mikhalev E, Thompson D, Warringer J, Liti G. Genome instability footprint under rapamycin and hydroxyurea treatments. PLoS Genet 2023; 19:e1011012. [PMID: 37931001 PMCID: PMC10653606 DOI: 10.1371/journal.pgen.1011012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 11/16/2023] [Accepted: 10/10/2023] [Indexed: 11/08/2023] Open
Abstract
The mutational processes dictating the accumulation of mutations in genomes are shaped by genetic background, environment and their interactions. Accurate quantification of mutation rates and spectra under drugs has important implications in disease treatment. Here, we used whole-genome sequencing and time-resolved growth phenotyping of yeast mutation accumulation lines to give a detailed view of the mutagenic effects of rapamycin and hydroxyurea on the genome and cell growth. Mutation rates depended on the genetic backgrounds but were only marginally affected by rapamycin. As a remarkable exception, rapamycin treatment was associated with frequent chromosome XII amplifications, which compensated for rapamycin induced rDNA repeat contraction on this chromosome and served to maintain rDNA content homeostasis and fitness. In hydroxyurea, a wide range of mutation rates were elevated regardless of the genetic backgrounds, with a particularly high occurrence of aneuploidy that associated with dramatic fitness loss. Hydroxyurea also induced a high T-to-G and low C-to-A transversion rate that reversed the common G/C-to-A/T bias in yeast and gave rise to a broad range of structural variants, including mtDNA deletions. The hydroxyurea mutation footprint was consistent with the activation of error-prone DNA polymerase activities and non-homologues end joining repair pathways. Taken together, our study provides an in-depth view of mutation rates and signatures in rapamycin and hydroxyurea and their impact on cell fitness, which brings insights for assessing their chronic effects on genome integrity.
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Affiliation(s)
- Jing Li
- State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou, P. R. China
- Université Côte d’Azur, CNRS, INSERM, IRCAN, Nice, France
| | - Simon Stenberg
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Jia-Xing Yue
- State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou, P. R. China
- Université Côte d’Azur, CNRS, INSERM, IRCAN, Nice, France
| | | | - Dawn Thompson
- Ginkgo Bioworks, Boston, Massachusetts, United States of America
| | - Jonas Warringer
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Gianni Liti
- Université Côte d’Azur, CNRS, INSERM, IRCAN, Nice, France
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6
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Jiang YK, Medley EA, Brown GW. Two independent DNA repair pathways cause mutagenesis in template switching deficient Saccharomyces cerevisiae. Genetics 2023; 225:iyad153. [PMID: 37594077 DOI: 10.1093/genetics/iyad153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 08/08/2023] [Indexed: 08/19/2023] Open
Abstract
Upon DNA replication stress, cells utilize the postreplication repair pathway to repair single-stranded DNA and maintain genome integrity. Postreplication repair is divided into 2 branches: error-prone translesion synthesis, signaled by proliferating cell nuclear antigen (PCNA) monoubiquitination, and error-free template switching, signaled by PCNA polyubiquitination. In Saccharomyces cerevisiae, Rad5 is involved in both branches of repair during DNA replication stress. When the PCNA polyubiquitination function of Rad5 s disrupted, Rad5 recruits translesion synthesis polymerases to stalled replication forks, resulting in mutagenic repair. Details of how mutagenic repair is carried out, as well as the relationship between Rad5-mediated mutagenic repair and the canonical PCNA-mediated mutagenic repair, remain to be understood. We find that Rad5-mediated mutagenic repair requires the translesion synthesis polymerase ζ but does not require other yeast translesion polymerase activities. Furthermore, we show that Rad5-mediated mutagenic repair is independent of PCNA binding by Rev1 and so is separable from canonical mutagenic repair. In the absence of error-free template switching, both modes of mutagenic repair contribute additively to replication stress response in a replication timing-independent manner. Cellular contexts where error-free template switching is compromised are not simply laboratory phenomena, as we find that a natural variant in RAD5 is defective in PCNA polyubiquitination and therefore defective in error-free repair, resulting in Rad5- and PCNA-mediated mutagenic repair. Our results highlight the importance of Rad5 in regulating spontaneous mutagenesis and genetic diversity in S. cerevisiae through different modes of postreplication repair.
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Affiliation(s)
- Yangyang Kate Jiang
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Eleanor A Medley
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Grant W Brown
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
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7
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Huang ZR, Chen XR, Liu DF, Cui YZ, Li BZ, Yuan YJ. Enhanced single-base mutation diversity by the combination of cytidine deaminase with DNA-repairing enzymes in yeast. Biotechnol J 2023; 18:e2300137. [PMID: 37529889 DOI: 10.1002/biot.202300137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 07/20/2023] [Accepted: 07/28/2023] [Indexed: 08/03/2023]
Abstract
The occurrence of random mutations can increase the diversity of the genome and promote the evolutionary process of organisms. High efficiency mutagenesis techniques significantly accelerate the evolutionary process. In this work, we describe a targeted mutagenesis system named MutaT7trans to significantly increase mutation rate and generate mutations across all four nucleotides in yeast. We constructed different DNA-repairing enzyme-PmCDA1-T7 RNA polymerase (T7 RNAP) fusion proteins, achieved targeted mutagenesis by flanking the target gene with T7 promoters, and tuned the mutation spectra by introducing different DNA-repairing enzymes. With this mutagenesis tool, the proportion of non-C → T mutations was 10-11-fold higher than the cytidine deaminase-based evolutionary tools, and the transversion mutation frequency was also elevated. The mutation rate of the target gene was significantly increased to 5.25 × 10-3 substitutions per base (s. p. b.). We also demonstrated that MutaT7trans could be used to evolve the CrtE, CrtI, and CrtYB gene in the β-carotene biosynthesis process and generate different types of mutations.
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Affiliation(s)
- Zi-Rui Huang
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Xiang-Rong Chen
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Dan-Feng Liu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - You-Zhi Cui
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Bing-Zhi Li
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Ying-Jin Yuan
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
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8
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Lynch M, Ali F, Lin T, Wang Y, Ni J, Long H. The divergence of mutation rates and spectra across the Tree of Life. EMBO Rep 2023; 24:e57561. [PMID: 37615267 PMCID: PMC10561183 DOI: 10.15252/embr.202357561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 08/25/2023] Open
Abstract
Owing to advances in genome sequencing, genome stability has become one of the most scrutinized cellular traits across the Tree of Life. Despite its centrality to all things biological, the mutation rate (per nucleotide site per generation) ranges over three orders of magnitude among species and several-fold within individual phylogenetic lineages. Within all major organismal groups, mutation rates scale negatively with the effective population size of a species and with the amount of functional DNA in the genome. This relationship is most parsimoniously explained by the drift-barrier hypothesis, which postulates that natural selection typically operates to reduce mutation rates until further improvement is thwarted by the power of random genetic drift. Despite this constraint, the molecular mechanisms underlying DNA replication fidelity and repair are free to wander, provided the performance of the entire system is maintained at the prevailing level. The evolutionary flexibility of the mutation rate bears on the resolution of several prior conundrums in phylogenetic and population-genetic analysis and raises challenges for future applications in these areas.
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Affiliation(s)
- Michael Lynch
- Biodesign Center for Mechanisms of EvolutionArizona State UniversityTempeAZUSA
| | - Farhan Ali
- Biodesign Center for Mechanisms of EvolutionArizona State UniversityTempeAZUSA
| | - Tongtong Lin
- Institute of Evolution and Marine Biodiversity, KLMMEOcean University of ChinaQingdaoChina
| | - Yaohai Wang
- Institute of Evolution and Marine Biodiversity, KLMMEOcean University of ChinaQingdaoChina
| | - Jiahao Ni
- Institute of Evolution and Marine Biodiversity, KLMMEOcean University of ChinaQingdaoChina
| | - Hongan Long
- Institute of Evolution and Marine Biodiversity, KLMMEOcean University of ChinaQingdaoChina
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Beichman AC, Robinson J, Lin M, Moreno-Estrada A, Nigenda-Morales S, Harris K. Evolution of the Mutation Spectrum Across a Mammalian Phylogeny. Mol Biol Evol 2023; 40:msad213. [PMID: 37770035 PMCID: PMC10566577 DOI: 10.1093/molbev/msad213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 08/21/2023] [Accepted: 09/19/2023] [Indexed: 10/03/2023] Open
Abstract
Although evolutionary biologists have long theorized that variation in DNA repair efficacy might explain some of the diversity of lifespan and cancer incidence across species, we have little data on the variability of normal germline mutagenesis outside of humans. Here, we shed light on the spectrum and etiology of mutagenesis across mammals by quantifying mutational sequence context biases using polymorphism data from thirteen species of mice, apes, bears, wolves, and cetaceans. After normalizing the mutation spectrum for reference genome accessibility and k-mer content, we use the Mantel test to deduce that mutation spectrum divergence is highly correlated with genetic divergence between species, whereas life history traits like reproductive age are weaker predictors of mutation spectrum divergence. Potential bioinformatic confounders are only weakly related to a small set of mutation spectrum features. We find that clock-like mutational signatures previously inferred from human cancers cannot explain the phylogenetic signal exhibited by the mammalian mutation spectrum, despite the ability of these signatures to fit each species' 3-mer spectrum with high cosine similarity. In contrast, parental aging signatures inferred from human de novo mutation data appear to explain much of the 1-mer spectrum's phylogenetic signal in combination with a novel mutational signature. We posit that future models purporting to explain the etiology of mammalian mutagenesis need to capture the fact that more closely related species have more similar mutation spectra; a model that fits each marginal spectrum with high cosine similarity is not guaranteed to capture this hierarchy of mutation spectrum variation among species.
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Affiliation(s)
- Annabel C Beichman
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Jacqueline Robinson
- Institute for Human Genetics, University of California, San Francisco, CA, USA
| | - Meixi Lin
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Andrés Moreno-Estrada
- National Laboratory of Genomics for Biodiversity, Advanced Genomics Unit (UGA-LANGEBIO), CINVESTAV, Irapuato, Mexico
| | - Sergio Nigenda-Morales
- Department of Biological Sciences, California State University, San Marcos, San Marcos, CA, USA
| | - Kelley Harris
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
- Herbold Computational Biology Program, Fred Hutchinson Cancer Center, Seattle, WA, USA
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10
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Beichman AC, Robinson J, Lin M, Moreno-Estrada A, Nigenda-Morales S, Harris K. "Evolution of the mutation spectrum across a mammalian phylogeny". BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.31.543114. [PMID: 37398383 PMCID: PMC10312511 DOI: 10.1101/2023.05.31.543114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Little is known about how the spectrum and etiology of germline mutagenesis might vary among mammalian species. To shed light on this mystery, we quantify variation in mutational sequence context biases using polymorphism data from thirteen species of mice, apes, bears, wolves, and cetaceans. After normalizing the mutation spectrum for reference genome accessibility and k -mer content, we use the Mantel test to deduce that mutation spectrum divergence is highly correlated with genetic divergence between species, whereas life history traits like reproductive age are weaker predictors of mutation spectrum divergence. Potential bioinformatic confounders are only weakly related to a small set of mutation spectrum features. We find that clocklike mutational signatures previously inferred from human cancers cannot explain the phylogenetic signal exhibited by the mammalian mutation spectrum, despite the ability of these clocklike signatures to fit each species' 3-mer spectrum with high cosine similarity. In contrast, parental aging signatures inferred from human de novo mutation data appear to explain much of the mutation spectrum's phylogenetic signal when fit to non-context-dependent mutation spectrum data in combination with a novel mutational signature. We posit that future models purporting to explain the etiology of mammalian mutagenesis need to capture the fact that more closely related species have more similar mutation spectra; a model that fits each marginal spectrum with high cosine similarity is not guaranteed to capture this hierarchy of mutation spectrum variation among species.
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Affiliation(s)
| | - Jacqueline Robinson
- Institute for Human Genetics, University of California, San Francisco, San Francisco, CA
| | - Meixi Lin
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA
| | - Andrés Moreno-Estrada
- National Laboratory of Genomics for Biodiversity, Advanced Genomics Unit (UGA-LANGEBIO), CINVESTAV, Irapuato, Mexico
| | - Sergio Nigenda-Morales
- Department of Biological Sciences, California State University, San Marcos, San Marcos CA
| | - Kelley Harris
- Department of Genome Sciences, University of Washington, Seattle WA
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11
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Sane M, Diwan GD, Bhat BA, Wahl LM, Agashe D. Shifts in mutation spectra enhance access to beneficial mutations. Proc Natl Acad Sci U S A 2023; 120:e2207355120. [PMID: 37216547 PMCID: PMC10235995 DOI: 10.1073/pnas.2207355120] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 03/27/2023] [Indexed: 05/24/2023] Open
Abstract
Biased mutation spectra are pervasive, with wide variation in the magnitude of mutational biases that influence genome evolution and adaptation. How do such diverse biases evolve? Our experiments show that changing the mutation spectrum allows populations to sample previously undersampled mutational space, including beneficial mutations. The resulting shift in the distribution of fitness effects is advantageous: Beneficial mutation supply and beneficial pleiotropy both increase, while deleterious load reduces. More broadly, simulations indicate that reducing or reversing the direction of a long-term bias is always selectively favored. Such changes in mutation bias can occur easily via altered function of DNA repair genes. A phylogenetic analysis shows that these genes are repeatedly gained and lost in bacterial lineages, leading to frequent bias shifts in opposite directions. Thus, shifts in mutation spectra may evolve under selection and can directly alter the outcome of adaptive evolution by facilitating access to beneficial mutations.
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Affiliation(s)
- Mrudula Sane
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru560065, India
| | - Gaurav D. Diwan
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru560065, India
- Bioquant, University of Heidelberg,69120Heidelberg, Germany
- Heidelberg University Biochemistry Center (BZH), 69120Heidelberg, Germany
| | - Bhoomika A. Bhat
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru560065, India
- Undergraduate Programme, Indian Institute of Science, Bengaluru 560012, India
| | - Lindi M. Wahl
- Mathematics, Western University, London, ON, N6A 5B7, Canada
| | - Deepa Agashe
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru560065, India
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12
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Bloom JD, Beichman AC, Neher RA, Harris K. Evolution of the SARS-CoV-2 Mutational Spectrum. Mol Biol Evol 2023; 40:msad085. [PMID: 37039557 PMCID: PMC10124870 DOI: 10.1093/molbev/msad085] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 02/07/2023] [Accepted: 04/06/2023] [Indexed: 04/12/2023] Open
Abstract
SARS-CoV-2 evolves rapidly in part because of its high mutation rate. Here, we examine whether this mutational process itself has changed during viral evolution. To do this, we quantify the relative rates of different types of single-nucleotide mutations at 4-fold degenerate sites in the viral genome across millions of human SARS-CoV-2 sequences. We find clear shifts in the relative rates of several types of mutations during SARS-CoV-2 evolution. The most striking trend is a roughly 2-fold decrease in the relative rate of G→T mutations in Omicron versus early clades, as was recently noted by Ruis et al. (2022. Mutational spectra distinguish SARS-CoV-2 replication niches. bioRxiv, doi:10.1101/2022.09.27.509649). There is also a decrease in the relative rate of C→T mutations in Delta, and other subtle changes in the mutation spectrum along the phylogeny. We speculate that these changes in the mutation spectrum could arise from viral mutations that affect genome replication, packaging, and antagonization of host innate-immune factors, although environmental factors could also play a role. Interestingly, the mutation spectrum of Omicron is more similar than that of earlier SARS-CoV-2 clades to the spectrum that shaped the long-term evolution of sarbecoviruses. Overall, our work shows that the mutation process is itself a dynamic variable during SARS-CoV-2 evolution and suggests that human SARS-CoV-2 may be trending toward a mutation spectrum more similar to that of other animal sarbecoviruses.
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Affiliation(s)
- Jesse D Bloom
- Basic Sciences Division and Computational Biology Program, Fred Hutchinson Cancer Center, Seattle, WA
- Department of Genome Sciences, University of Washington, Seattle, WA
- Howard Hughes Medical Institute, Seattle, WA
| | | | - Richard A Neher
- Biozentrum, University of Basel, Basel, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Kelley Harris
- Department of Genome Sciences, University of Washington, Seattle, WA
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13
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Tu X, Wang F, Liti G, Breitenbach M, Yue JX, Li J. Spontaneous Mutation Rates and Spectra of Respiratory-Deficient Yeast. Biomolecules 2023; 13:501. [PMID: 36979436 PMCID: PMC10046086 DOI: 10.3390/biom13030501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/05/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
The yeast petite mutant was first discovered in the yeast Saccharomyces cerevisiae, which shows growth stress due to defects in genes encoding the respiratory chain. In a previous study, we described that deletion of the nuclear-encoded gene MRPL25 leads to mitochondrial genome (mtDNA) loss and the petite phenotype, which can be rescued by acquiring ATP3 mutations. The mrpl25Δ strain showed an elevated SNV (single nucleotide variant) rate, suggesting genome instability occurred during the crisis of mtDNA loss. However, the genome-wide mutation landscape and mutational signatures of mitochondrial dysfunction are unknown. In this study we profiled the mutation spectra in yeast strains with the genotype combination of MRPL25 and ATP3 in their wildtype and mutated status, along with the wildtype and cytoplasmic petite rho0 strains as controls. In addition to the previously described elevated SNV rate, we found the INDEL (insertion/deletion) rate also increased in the mrpl25Δ strain, reinforcing the occurrence of genome instability. Notably, although both are petites, the mrpl25Δ and rho0 strains exhibited different INDEL rates and transition/transversion ratios, suggesting differences in the mutational signatures underlying these two types of petites. Interestingly, the petite-related mutagenesis effect disappeared when ATP3 suppressor mutations were acquired, suggesting a cost-effective mechanism for restoring both fitness and genome stability. Taken together, we present an unbiased genome-wide characterization of the mutation rates and spectra of yeast strains with respiratory deficiency, which provides valuable insights into the impact of respiratory deficiency on genome instability.
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Affiliation(s)
- Xinyu Tu
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Fan Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Gianni Liti
- IRCAN, INSERM, Université Côte d’Azur, 06107 Nice, France
| | | | - Jia-Xing Yue
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Jing Li
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
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14
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Gao Z, Zhang Y, Cramer N, Przeworski M, Moorjani P. Limited role of generation time changes in driving the evolution of the mutation spectrum in humans. eLife 2023; 12:e81188. [PMID: 36779395 PMCID: PMC10014080 DOI: 10.7554/elife.81188] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 02/02/2023] [Indexed: 02/14/2023] Open
Abstract
Recent studies have suggested that the human germline mutation rate and spectrum evolve rapidly. Variation in generation time has been linked to these changes, though its contribution remains unclear. We develop a framework to characterize temporal changes in polymorphisms within and between populations, while controlling for the effects of natural selection and biased gene conversion. Application to the 1000 Genomes Project dataset reveals multiple independent changes that arose after the split of continental groups, including a previously reported, transient elevation in TCC>TTC mutations in Europeans and novel signals of divergence in C>Gand T>A mutation rates among population samples. We also find a significant difference between groups sampled in and outside of Africa in old T>C polymorphisms that predate the out-of-Africa migration. This surprising signal is driven by TpG>CpG mutations and stems in part from mis-polarized CpG transitions, which are more likely to undergo recurrent mutations. Finally, by relating the mutation spectrum of polymorphisms to parental age effects on de novo mutations, we show that plausible changes in the generation time cannot explain the patterns observed for different mutation types jointly. Thus, other factors - genetic modifiers or environmental exposures - must have had a non-negligible impact on the human mutation landscape.
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Affiliation(s)
- Ziyue Gao
- Department of Genetics, University of Pennsylvania, Perelman School of MedicinePhiladelphiaUnited States
| | - Yulin Zhang
- Center for Computational Biology, University of California, BerkeleyBerkeleyUnited States
| | - Nathan Cramer
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Molly Przeworski
- Department of Biological Sciences, Columbia UniversityNew YorkUnited States
- Department of Systems Biology, Columbia UniversityNew YorkUnited States
| | - Priya Moorjani
- Center for Computational Biology, University of California, BerkeleyBerkeleyUnited States
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
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15
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Pai CC, Heitzer E, Bertrand S, Toumazou S, Humphrey TC, Kearsey SE. Using canavanine resistance to measure mutation rates in Schizosaccharomyces pombe. PLoS One 2023; 18:e0271016. [PMID: 36626373 PMCID: PMC9831302 DOI: 10.1371/journal.pone.0271016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 12/19/2022] [Indexed: 01/11/2023] Open
Abstract
We constructed a panel of S. pombe strains expressing DNA polymerase ε variants associated with cancer, specifically POLES297F, POLEV411L, POLEL424V, POLES459F, and used these to compare mutation rates determined by canavanine resistance with other selective methods. Canavanine-resistance mutation rates are broadly similar to those seen with reversion of the ade-485 mutation to adenine prototrophy, but lower than 5-fluoroorotic acid (FOA)-resistance rates (inactivation of ura4+ or ura5+ genes). Inactivation of several genes has been associated with canavanine resistance in S. pombe but surprisingly whole genome sequencing showed that 8/8 spontaneous canavanine-resistant mutants have an R175C mutation in the any1/arn1 gene. This gene encodes an α-arrestin-like protein involved in mediating Pub1 ubiquitylation of target proteins, and the phenotypic resistance to canavanine by this single mutation is similar to that shown by the original "can1-1" strain, which also has the any1R175C mutation. Some of the spontaneous mutants have additional mutations in arginine transporters, suggesting that this may marginally increase resistance to canavanine. The any1R175C strain showed internalisation of the Cat1 arginine transporter as previously reported, explaining the canavanine-resistance phenotype.
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Affiliation(s)
- Chen-Chun Pai
- Department of Oncology, CRUK-MRC Oxford Institute for Radiation Oncology, University of Oxford, ORCRB, Oxford, United Kingdom
| | - Ellen Heitzer
- Institute of Human Genetics, Diagnostic & Research Center for Molecular BioMedicine, Medical University of Graz, Graz, Austria
| | | | | | - Timothy C. Humphrey
- Department of Oncology, CRUK-MRC Oxford Institute for Radiation Oncology, University of Oxford, ORCRB, Oxford, United Kingdom
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16
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Bloom JD, Beichman AC, Neher RA, Harris K. Evolution of the SARS-CoV-2 mutational spectrum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022:2022.11.19.517207. [PMID: 36451887 PMCID: PMC9709787 DOI: 10.1101/2022.11.19.517207] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
SARS-CoV-2 evolves rapidly in part because of its high mutation rate. Here we examine whether this mutational process itself has changed during viral evolution. To do this, we quantify the relative rates of different types of single nucleotide mutations at four-fold degenerate sites in the viral genome across millions of human SARS-CoV-2 sequences. We find clear shifts in the relative rates of several types of mutations during SARS-CoV-2 evolution. The most striking trend is a roughly two-fold decrease in the relative rate of G→T mutations in Omicron versus early clades, as was recently noted by Ruis et al (2022). There is also a decrease in the relative rate of C→T mutations in Delta, and other subtle changes in the mutation spectrum along the phylogeny. We speculate that these changes in the mutation spectrum could arise from viral mutations that affect genome replication, packaging, and antagonization of host innate-immune factors-although environmental factors could also play a role. Interestingly, the mutation spectrum of Omicron is more similar than that of earlier SARS-CoV-2 clades to the spectrum that shaped the long-term evolution of sarbecoviruses. Overall, our work shows that the mutation process is itself a dynamic variable during SARS-CoV-2 evolution, and suggests that human SARS-CoV-2 may be trending towards a mutation spectrum more similar to that of other animal sarbecoviruses.
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Affiliation(s)
- Jesse D Bloom
- Basic Sciences Division and Computational Biology Program, Fred Hutchinson Cancer Center, Seattle, Washington, USA
- Department of Genome Sciences & Medical Scientist Training Program, University of Washington, Seattle, Washington, USA
- Howard Hughes Medical Institute, Seattle, WA, USA
| | - Annabel C Beichman
- Department of Genome Sciences & Medical Scientist Training Program, University of Washington, Seattle, Washington, USA
| | - Richard A Neher
- Biozentrum, University of Basel, Basel, Switzerland, Swiss Institute of Bioinformatics, Lausanne, Switzerland
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17
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Zhu Q, Lin Y, Lyu X, Qu Z, Lu Z, Fu Y, Cheng J, Xie J, Chen T, Li B, Cheng H, Chen W, Jiang D. Fungal Strains with Identical Genomes Were Found at a Distance of 2000 Kilometers after 40 Years. J Fungi (Basel) 2022; 8:1212. [PMID: 36422033 PMCID: PMC9697809 DOI: 10.3390/jof8111212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 10/26/2022] [Accepted: 11/11/2022] [Indexed: 11/26/2023] Open
Abstract
Heredity and variation are inherent characteristics of species and are mainly reflected in the stability and variation of the genome; the former is relative, while the latter is continuous. However, whether life has both stable genomes and extremely diverse genomes at the same time is unknown. In this study, we isolated Sclerotinia sclerotiorum strains from sclerotium samples in Quincy, Washington State, USA, and found that four single-sclerotium-isolation strains (PB4, PB273, PB615, and PB623) had almost identical genomes to the reference strain 1980 isolated in the west of Nebraska 40 years ago. The genome of strain PB4 sequenced by the next-generation sequencing (NGS) and Pacific Biosciences (PacBio) sequencing carried only 135 single nucleotide polymorphisms (SNPs) and 18 structural variations (SVs) compared with the genome of strain 1980 and 48 SNPs were distributed on Contig_20. Based on data generated by NGS, three other strains, PB273, PB615, and PB623, had 256, 275, and 262 SNPs, respectively, against strain 1980, which were much less than in strain PB4 (532 SNPs) and none of them occurred on Contig_20, suggesting much closer genomes to strain 1980 than to strain PB4. All other strains from America and China are rich in SNPs with a range of 34,391-77,618 when compared with strain 1980. We also found that there were 39-79 SNPs between strain PB4 and its sexual offspring, 53.1% of which also occurred on Contig_20. Our discoveries show that there are two types of genomes in S. sclerotiorum, one is very stable and the other tends to change constantly. Investigating the mechanism of such genome stability will enhance our understanding of heredity and variation.
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Affiliation(s)
- Qili Zhu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yang Lin
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Xueliang Lyu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Zheng Qu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Ziyang Lu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yanping Fu
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jiasen Cheng
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jiatao Xie
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Tao Chen
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Bo Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Hui Cheng
- Xinyang Academy of Agricultural Sciences, Xinyang 464000, China
| | - Weidong Chen
- United States Department of Agriculture, Agricultural Research Service, Washington State University, Pullman, WA 99164, USA
| | - Daohong Jiang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
- Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
- Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan 430070, China
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518000, China
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18
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Melde RH, Bao K, Sharp NP. Recent insights into the evolution of mutation rates in yeast. Curr Opin Genet Dev 2022; 76:101953. [PMID: 35834945 PMCID: PMC9491374 DOI: 10.1016/j.gde.2022.101953] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 05/25/2022] [Accepted: 06/13/2022] [Indexed: 02/08/2023]
Abstract
Mutation is the origin of all genetic variation, good and bad. The mutation process can evolve in response to mutations, positive or negative selection, and genetic drift, but how these forces contribute to mutation-rate variation is an unsolved problem at the heart of genetics research. Mutations can be challenging to measure, but genome sequencing and other tools have allowed for the collection of larger and more detailed datasets, particularly in the yeast-model system. We review key hypotheses for the evolution of mutation rates and describe recent advances in understanding variation in mutational properties within and among yeast species. The multidimensional spectrum of mutations is increasingly recognized as holding valuable clues about how this important process evolves.
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Affiliation(s)
- Robert H Melde
- Department of Genetics, University of Wisconsin-Madison, USA.
| | - Kevin Bao
- Department of Genetics, University of Wisconsin-Madison, USA
| | - Nathaniel P Sharp
- Department of Genetics, University of Wisconsin-Madison, USA. https://twitter.com/@sharpnath
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19
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Jiang P, Ollodart AR, Dunham MJ. A Modified Fluctuation Assay with a CAN1 Reporter in Yeast. Bio Protoc 2022; 12:e4435. [PMID: 35799910 PMCID: PMC9243513 DOI: 10.21769/bioprotoc.4435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/29/2022] [Accepted: 05/03/2022] [Indexed: 12/29/2022] Open
Abstract
Understanding the generation of mutations is fundamental to understanding evolution and genetic disease; however, the rarity of such events makes experimentally identifying them difficult. Mutation accumulation (MA) methods have been widely used. MA lines require serial bottlenecks to fix de novo mutations, followed by whole-genome sequencing. While powerful, this method is not suitable for exploring mutation variation among different genotypes due to its poor scalability with cost and labor. Alternatively, fluctuation assays estimate mutation rate in microorganisms by utilizing a reporter gene, in which Loss-of-function (LOF) mutations can be selected for using drugs toxic to cells containing the WT allele. Traditional fluctuation assays can estimate mutation rates but not their base change compositions. Here, we describe a new protocol that adapts traditional fluctuation assay using CAN1 reporter gene in Saccharomyces cerevisiae , followed by pooled sequencing methods, to identify both the rate and spectra of mutations in different strain backgrounds.
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Affiliation(s)
- Pengyao Jiang
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Anja R. Ollodart
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
| | - Maitreya J. Dunham
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
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20
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Yang YS, Ning SK, Lyu XH, Suo F, Jia GS, Li W, Du LL. Canavanine resistance mutation can1-1 in Schizosaccharomyces pombe is a missense mutation in the ubiquitin ligase adaptor gene any1. MICROPUBLICATION BIOLOGY 2022; 2022:10.17912/micropub.biology.000538. [PMID: 35300005 PMCID: PMC8922049 DOI: 10.17912/micropub.biology.000538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/05/2022] [Accepted: 03/09/2022] [Indexed: 11/18/2022]
Abstract
In Schizosaccharomyces pombe, the can1-1 mutation confers resistance to the toxic arginine analog canavanine. This mutation has been assumed to disrupt a gene encoding an arginine transporter. In PomBase, the gene SPBC18H10.16 is currently designated can1. Here, we sequenced the genomes of three can1-1 strains. No mutations were found in SPBC18H10.16. Instead, these strains harbor an R175C mutation in the gene any1 (SPBC18H10.20c). any1 encodes an α-arrestin that acts as a ubiquitin ligase adaptor to downregulate plasma membrane amino acid transporters. Our findings indicate that can1-1 is not a loss-of-function mutation in an amino acid transporter gene, but a possible gain-of-function mutation in a gene encoding a negative regulator of amino acid transporters.
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Affiliation(s)
- Yu-Sheng Yang
- National Institute of Biological Sciences, Beijing, China
| | - Shao-Kai Ning
- National Institute of Biological Sciences, Beijing, China
| | - Xiao-Hui Lyu
- National Institute of Biological Sciences, Beijing, China
| | - Fang Suo
- National Institute of Biological Sciences, Beijing, China
| | - Guo-Song Jia
- National Institute of Biological Sciences, Beijing, China
| | - Wen Li
- National Institute of Biological Sciences, Beijing, China
| | - Li-Lin Du
- National Institute of Biological Sciences, Beijing, China
,
Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China
,
Correspondence to: Li-Lin Du (
)
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21
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Fijarczyk A, Hénault M, Marsit S, Charron G, Landry CR. Heterogeneous Mutation Rates and Spectra in Yeast Hybrids. Genome Biol Evol 2021; 13:6462191. [PMID: 34908117 PMCID: PMC8715523 DOI: 10.1093/gbe/evab282] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2021] [Indexed: 12/11/2022] Open
Abstract
Mutation rates and spectra vary between species and among populations. Hybridization can contribute to this variation, but its role remains poorly understood. Estimating mutation rates requires controlled conditions where the effect of natural selection can be minimized. One way to achieve this is through mutation accumulation experiments coupled with genome sequencing. Here, we investigate 400 mutation accumulation lines initiated from 11 genotypes spanning intralineage, interlineage, and interspecific crosses of the yeasts Saccharomyces paradoxus and S. cerevisiae and propagated for 770 generations. We find significant differences in mutation rates and spectra among crosses, which are not related to the level of divergence of parental strains but are specific to some genotype combinations. Differences in number of generations and departures from neutrality play a minor role, whereas polyploidy and loss of heterozygosity impact mutation rates in some of the hybrid crosses in an opposite way.
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Affiliation(s)
- Anna Fijarczyk
- Département de Biologie, Université Laval, Québec, Québec, Canada.,Institut de Biologie Intégrative et des Systemes (IBIS), Université Laval, Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bioinformatique, Université Laval, Québec, Québec, Canada.,PROTEO, Le Réseau Québécois de Recherche sur la Fonction, La Structure et L'Ingénierie des Protéines, Université Laval, Québec, Québec, Canada.,Centre de Recherche en Données Massives (CRDM), Université Laval, Québec, Québec, Canada
| | - Mathieu Hénault
- Département de Biologie, Université Laval, Québec, Québec, Canada.,Institut de Biologie Intégrative et des Systemes (IBIS), Université Laval, Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bioinformatique, Université Laval, Québec, Québec, Canada.,PROTEO, Le Réseau Québécois de Recherche sur la Fonction, La Structure et L'Ingénierie des Protéines, Université Laval, Québec, Québec, Canada.,Centre de Recherche en Données Massives (CRDM), Université Laval, Québec, Québec, Canada
| | - Souhir Marsit
- Département de Biologie, Université Laval, Québec, Québec, Canada.,Institut de Biologie Intégrative et des Systemes (IBIS), Université Laval, Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bioinformatique, Université Laval, Québec, Québec, Canada.,PROTEO, Le Réseau Québécois de Recherche sur la Fonction, La Structure et L'Ingénierie des Protéines, Université Laval, Québec, Québec, Canada.,Centre de Recherche en Données Massives (CRDM), Université Laval, Québec, Québec, Canada
| | - Guillaume Charron
- Département de Biologie, Université Laval, Québec, Québec, Canada.,Institut de Biologie Intégrative et des Systemes (IBIS), Université Laval, Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bioinformatique, Université Laval, Québec, Québec, Canada.,PROTEO, Le Réseau Québécois de Recherche sur la Fonction, La Structure et L'Ingénierie des Protéines, Université Laval, Québec, Québec, Canada.,Centre de Recherche en Données Massives (CRDM), Université Laval, Québec, Québec, Canada
| | - Christian R Landry
- Département de Biologie, Université Laval, Québec, Québec, Canada.,Institut de Biologie Intégrative et des Systemes (IBIS), Université Laval, Québec, Québec, Canada.,Département de Biochimie, Microbiologie et Bioinformatique, Université Laval, Québec, Québec, Canada.,PROTEO, Le Réseau Québécois de Recherche sur la Fonction, La Structure et L'Ingénierie des Protéines, Université Laval, Québec, Québec, Canada.,Centre de Recherche en Données Massives (CRDM), Université Laval, Québec, Québec, Canada
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22
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Jiang P, Ollodart AR, Sudhesh V, Herr AJ, Dunham MJ, Harris K. A modified fluctuation assay reveals a natural mutator phenotype that drives mutation spectrum variation within Saccharomyces cerevisiae. eLife 2021; 10:68285. [PMID: 34523420 PMCID: PMC8497059 DOI: 10.7554/elife.68285] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 09/14/2021] [Indexed: 12/23/2022] Open
Abstract
Although studies of Saccharomyces cerevisiae have provided many insights into mutagenesis and DNA repair, most of this work has focused on a few laboratory strains. Much less is known about the phenotypic effects of natural variation within S. cerevisiae’s DNA repair pathways. Here, we use natural polymorphisms to detect historical mutation spectrum differences among several wild and domesticated S. cerevisiae strains. To determine whether these differences are likely caused by genetic mutation rate modifiers, we use a modified fluctuation assay with a CAN1 reporter to measure de novo mutation rates and spectra in 16 of the analyzed strains. We measure a 10-fold range of mutation rates and identify two strains with distinctive mutation spectra. These strains, known as AEQ and AAR, come from the panel’s ‘Mosaic beer’ clade and share an enrichment for C > A mutations that is also observed in rare variation segregating throughout the genomes of several Mosaic beer and Mixed origin strains. Both AEQ and AAR are haploid derivatives of the diploid natural isolate CBS 1782, whose rare polymorphisms are enriched for C > A as well, suggesting that the underlying mutator allele is likely active in nature. We use a plasmid complementation test to show that AAR and AEQ share a mutator allele in the DNA repair gene OGG1, which excises 8-oxoguanine lesions that can cause C > A mutations if left unrepaired.
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Affiliation(s)
- Pengyao Jiang
- Department of Genome Sciences, University of Washington, Seattle, United States
| | - Anja R Ollodart
- Department of Genome Sciences, University of Washington, Seattle, United States.,Molecular and Cellular Biology Program, University of Washington, Seattle, United States
| | - Vidha Sudhesh
- Department of Genome Sciences, University of Washington, Seattle, United States
| | - Alan J Herr
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, United States
| | - Maitreya J Dunham
- Department of Genome Sciences, University of Washington, Seattle, United States
| | - Kelley Harris
- Department of Genome Sciences, University of Washington, Seattle, United States.,Department of Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, United States
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