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Desroches Altamirano C, Kang MK, Jordan MA, Borianne T, Dilmen I, Gnädig M, von Appen A, Honigmann A, Franzmann TM, Alberti S. eIF4F is a thermo-sensing regulatory node in the translational heat shock response. Mol Cell 2024; 84:1727-1741.e12. [PMID: 38547866 DOI: 10.1016/j.molcel.2024.02.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 12/18/2023] [Accepted: 02/29/2024] [Indexed: 05/05/2024]
Abstract
Heat-shocked cells prioritize the translation of heat shock (HS) mRNAs, but the underlying mechanism is unclear. We report that HS in budding yeast induces the disassembly of the eIF4F complex, where eIF4G and eIF4E assemble into translationally arrested mRNA ribonucleoprotein particles (mRNPs) and HS granules (HSGs), whereas eIF4A promotes HS translation. Using in vitro reconstitution biochemistry, we show that a conformational rearrangement of the thermo-sensing eIF4A-binding domain of eIF4G dissociates eIF4A and promotes the assembly with mRNA into HS-mRNPs, which recruit additional translation factors, including Pab1p and eIF4E, to form multi-component condensates. Using extracts and cellular experiments, we demonstrate that HS-mRNPs and condensates repress the translation of associated mRNA and deplete translation factors that are required for housekeeping translation, whereas HS mRNAs can be efficiently translated by eIF4A. We conclude that the eIF4F complex is a thermo-sensing node that regulates translation during HS.
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Affiliation(s)
- Christine Desroches Altamirano
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Moo-Koo Kang
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Mareike A Jordan
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Tom Borianne
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Irem Dilmen
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Maren Gnädig
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Alexander von Appen
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Alf Honigmann
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Titus M Franzmann
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Simon Alberti
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany.
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2
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Brettrager EJ, Frederick AJ, van Waardenburg RCAM. Zymolyase Treatment of Saccharomyces cerevisiae Affects Cellular Proteins and Degrades Tyrosyl-DNA Phosphodiesterase I. DNA Cell Biol 2024. [PMID: 38682313 DOI: 10.1089/dna.2024.0062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024] Open
Abstract
Saccharomyces cerevisiae is a genetically tractable, affordable, and extensively documented eukaryotic single-cell model organism. This budding yeast is amenable for the development of genetic and biochemical experiments and is frequently used to investigate the function, activity, and mechanism of mammalian proteins. However, yeast contains a cell wall that hinders select assays including organelle isolation. Lytic enzymes, with Zymolyase as the most effective and frequently used tool, are utilized to weaken the yeast cell wall resulting in yeast spheroplasts. Spheroplasts are easily lysed by, for example, osmotic-shock conditions to isolate yeast nuclei or mitochondria. However, during our studies of the DNA repair enzyme tyrosyl-DNA phosphodiesterase I (Tdp1), we encountered a negative effect of Zymolyase. We observed that Zymolyase treatment affected the steady-state protein levels of Tdp1. This was revealed by inconsistencies in technical and biological replicate lysates of plasmid-born galactose-induced expression of Tdp1. This off-target effect of Zymolyase is rarely discussed in articles and affects a select number of intracellular proteins, including transcription factors and assays such as chromatin immunoprecipitations. Following extensive troubleshooting, we concluded that the culprit is the Ser-protease, Zymolyase B, component of the Zymolyase enzyme mixture that causes the degradation of Tdp1. In this study, we report the protocols we have used, and our final protocol with an easy, affordable adaptation to any assay/protocol involving Zymolyase.
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Affiliation(s)
- Evan J Brettrager
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Aaron J Frederick
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama, USA
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Ushiyama Y, Nishida I, Tomiyama S, Tanaka H, Kume K, Hirata D. Search for protein kinase(s) related to cell growth or viability maintenance in the presence of ethanol in budding and fission yeasts. Biosci Biotechnol Biochem 2024:zbae044. [PMID: 38592956 DOI: 10.1093/bbb/zbae044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Alcohol fermentation comprises two phases: phase 1, alcohol fermentation occurs while yeast cells proliferate; phase 2, growth stops and alcohol fermentation continues. We categorized genes related to proliferation in low ethanol (phase 1) and viability in high ethanol (phase 2) as Alcohol Growth Ability (AGA) and Alcohol Viability (ALV), respectively. Although genes required for phase 1 are examined in budding yeast, those for phase 2 are unknown. We set conditions for ALV screening, searched for protein kinases (PKs) related to ALV in budding yeast, and expanded two screenings to fission yeast. Bub1 kinase was important for proliferation in low ethanol but not for viability in high ethanol, suggesting that the important PKs differ between the two phases. It was indeed the case. Further, three common PKs were identified as AGA in both yeasts, suggesting that the important cellular mechanism in phase 1 is conserved in both yeasts, at least partially.
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Affiliation(s)
- Yuto Ushiyama
- Sakeology Course, Graduate School of Science and Technology, Niigata University, 2-8050, Ikarashi, Niigata, 950-2181, Japan
| | - Ikuhisa Nishida
- Sakeology Center, Niigata University, 2-8050, Ikarashi, Niigata, 950-2181, Japan
| | - Saki Tomiyama
- Sakeology Course, Graduate School of Science and Technology, Niigata University, 2-8050, Ikarashi, Niigata, 950-2181, Japan
| | - Hitomi Tanaka
- Sakeology Course, Graduate School of Science and Technology, Niigata University, 2-8050, Ikarashi, Niigata, 950-2181, Japan
| | - Kazunori Kume
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
| | - Dai Hirata
- Sakeology Course, Graduate School of Science and Technology, Niigata University, 2-8050, Ikarashi, Niigata, 950-2181, Japan
- Sakeology Center, Niigata University, 2-8050, Ikarashi, Niigata, 950-2181, Japan
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan
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Meier SM, Steinmetz MO, Barral Y. Microtubule specialization by +TIP networks: from mechanisms to functional implications. Trends Biochem Sci 2024; 49:318-332. [PMID: 38350804 DOI: 10.1016/j.tibs.2024.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/23/2023] [Accepted: 01/12/2024] [Indexed: 02/15/2024]
Abstract
To fulfill their actual cellular role, individual microtubules become functionally specialized through a broad range of mechanisms. The 'search and capture' model posits that microtubule dynamics and functions are specified by cellular targets that they capture (i.e., a posteriori), independently of the microtubule-organizing center (MTOC) they emerge from. However, work in budding yeast indicates that MTOCs may impart a functional identity to the microtubules they nucleate, a priori. Key effectors in this process are microtubule plus-end tracking proteins (+TIPs), which track microtubule tips to regulate their dynamics and facilitate their targeted interactions. In this review, we discuss potential mechanisms of a priori microtubule specialization, focusing on recent findings indicating that +TIP networks may undergo liquid biomolecular condensation in different cell types.
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Affiliation(s)
- Sandro M Meier
- Institute of Biochemistry, Department of Biology, and Bringing Materials to Life Initiative, ETH Zürich, Switzerland; Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, Villigen, Switzerland; Bringing Materials to Life Initiative, ETH Zürich, Switzerland
| | - Michel O Steinmetz
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, Villigen, Switzerland; University of Basel, Biozentrum, CH-4056 Basel, Switzerland.
| | - Yves Barral
- Institute of Biochemistry, Department of Biology, and Bringing Materials to Life Initiative, ETH Zürich, Switzerland; Bringing Materials to Life Initiative, ETH Zürich, Switzerland.
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5
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Stochaj U. Yeast profilin mutants inhibit classical nuclear import and alter the balance between actin and tubulin levels. Biochem Cell Biol 2024; 102:206-212. [PMID: 38048555 DOI: 10.1139/bcb-2023-0223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/06/2023] Open
Abstract
Profilin is a small protein that controls actin polymerization in yeast and higher eukaryotes. In addition, profilin has emerged as a multifunctional protein that contributes to other processes in multicellular organisms. This study focuses on profilin (Pfy1) in the budding yeast Saccharomyces cerevisiae. The primary sequences of yeast Pfy1 and its metazoan orthologs diverge vastly. However, structural elements of profilin are conserved among different species. To date, the full spectrum of Pfy1 functions has yet to be defined. The current work explores the possible involvement of yeast profilin in nuclear protein import. To this end, a panel of well-characterized yeast profilin mutants was evaluated. The experiments demonstrate that yeast profilin (i) regulates nuclear protein import, (ii) determines the subcellular localization of essential nuclear transport factors, and (iii) controls the relative abundance of actin and tubulin. Together, these results define yeast profilin as a moonlighting protein that engages in multiple essential cellular activities.
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Affiliation(s)
- Ursula Stochaj
- Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada
- Quantitative Life Sciences Program, McGill University, Montreal, QC H3G 1Y6, Canada
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Wang Y, Ruan L, Li R. GPI-anchored Gas1 protein regulates cytosolic proteostasis in budding yeast. G3 (Bethesda) 2024; 14:jkad263. [PMID: 38289859 PMCID: PMC10917523 DOI: 10.1093/g3journal/jkad263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Accepted: 11/01/2023] [Indexed: 02/01/2024]
Abstract
The decline in protein homeostasis (proteostasis) is a hallmark of cellular aging and aging-related diseases. Maintaining a balanced proteostasis requires a complex network of molecular machineries that govern protein synthesis, folding, localization, and degradation. Under proteotoxic stress, misfolded proteins that accumulate in cytosol can be imported into mitochondria for degradation through the "mitochondrial as guardian in cytosol" (MAGIC) pathway. Here, we report an unexpected role of Gas1, a cell wall-bound glycosylphosphatidylinositol (GPI)-anchored β-1,3-glucanosyltransferase in the budding yeast, in differentially regulating MAGIC and ubiquitin-proteasome system (UPS). Deletion of GAS1 inhibits MAGIC but elevates protein ubiquitination and UPS-mediated protein degradation. Interestingly, we found that the Gas1 protein exhibits mitochondrial localization attributed to its C-terminal GPI anchor signal. But this mitochondria-associated GPI anchor signal is not required for mitochondrial import and degradation of misfolded proteins through MAGIC. By contrast, catalytic inactivation of Gas1 via the gas1-E161Q mutation inhibits MAGIC but not its mitochondrial localization. These data suggest that the glucanosyltransferase activity of Gas1 is important for regulating cytosolic proteostasis.
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Affiliation(s)
- Yuhao Wang
- Center for Cell Dynamics and Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Biochemistry, Cellular and Molecular Biology (BCMB) Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Linhao Ruan
- Center for Cell Dynamics and Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Rong Li
- Center for Cell Dynamics and Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Mechanobiology Institute and Department of Biological Sciences, National University of Singapore, Singapore 117411, Singapore
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7
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Li S, Kasciukovic T, Tanaka TU. Kinetochore-microtubule error correction for biorientation: lessons from yeast. Biochem Soc Trans 2024; 52:29-39. [PMID: 38305688 PMCID: PMC10903472 DOI: 10.1042/bst20221261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 02/03/2024]
Abstract
Accurate chromosome segregation in mitosis relies on sister kinetochores forming stable attachments to microtubules (MTs) extending from opposite spindle poles and establishing biorientation. To achieve this, erroneous kinetochore-MT interactions must be resolved through a process called error correction, which dissolves improper kinetochore-MT attachment and allows new interactions until biorientation is achieved. The Aurora B kinase plays key roles in driving error correction by phosphorylating Dam1 and Ndc80 complexes, while Mps1 kinase, Stu2 MT polymerase and phosphatases also regulate this process. Once biorientation is formed, tension is applied to kinetochore-MT interaction, stabilizing it. In this review article, we discuss the mechanisms of kinetochore-MT interaction, error correction and biorientation. We focus mainly on recent insights from budding yeast, where the attachment of a single MT to a single kinetochore during biorientation simplifies the analysis of error correction mechanisms.
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Affiliation(s)
- Shuyu Li
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Taciana Kasciukovic
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Tomoyuki U. Tanaka
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
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8
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Durant M, Mucelli X, Huang LS. Meiotic Cytokinesis in Saccharomyces cerevisiae: Spores That Just Need Closure. J Fungi (Basel) 2024; 10:132. [PMID: 38392804 PMCID: PMC10890087 DOI: 10.3390/jof10020132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 01/30/2024] [Accepted: 02/04/2024] [Indexed: 02/24/2024] Open
Abstract
In the budding yeast Saccharomyces cerevisiae, sporulation occurs during starvation of a diploid cell and results in the formation of four haploid spores forming within the mother cell ascus. Meiosis divides the genetic material that is encapsulated by the prospore membrane that grows to surround the haploid nuclei; this membrane will eventually become the plasma membrane of the haploid spore. Cellularization of the spores occurs when the prospore membrane closes to capture the haploid nucleus along with some cytoplasmic material from the mother cell, and thus, closure of the prospore membrane is the meiotic cytokinetic event. This cytokinetic event involves the removal of the leading-edge protein complex, a complex of proteins that localizes to the leading edge of the growing prospore membrane. The development and closure of the prospore membrane must be coordinated with other meiotic exit events such as spindle disassembly. Timing of the closure of the prospore membrane depends on the meiotic exit pathway, which utilizes Cdc15, a Hippo-like kinase, and Sps1, an STE20 family GCKIII kinase, acting in parallel to the E3 ligase Ama1-APC/C. This review describes the sporulation process and focuses on the development of the prospore membrane and the regulation of prospore membrane closure.
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Affiliation(s)
- Matthew Durant
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Xheni Mucelli
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Linda S Huang
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
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9
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Ohya Y, Ghanegolmohammadi F, Itto-Nakama K. Application of unimodal probability distribution models for morphological phenotyping of budding yeast. FEMS Yeast Res 2024; 24:foad056. [PMID: 38169030 PMCID: PMC10804223 DOI: 10.1093/femsyr/foad056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/28/2023] [Accepted: 12/30/2023] [Indexed: 01/05/2024] Open
Abstract
Morphological phenotyping of the budding yeast Saccharomyces cerevisiae has helped to greatly clarify the functions of genes and increase our understanding of cellular functional networks. It is necessary to understand cell morphology and perform quantitative morphological analysis (QMA) but assigning precise values to morphological phenotypes has been challenging. We recently developed the Unimodal Morphological Data image analysis pipeline for this purpose. All true values can be estimated theoretically by applying an appropriate probability distribution if the distribution of experimental values follows a unimodal pattern. This reliable pipeline allows several downstream analyses, including detection of subtle morphological differences, selection of mutant strains with similar morphology, clustering based on morphology, and study of morphological diversity. In addition to basic research, morphological analyses of yeast cells can also be used in applied research to monitor breeding and fermentation processes and control the fermentation activity of yeast cells.
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Affiliation(s)
- Yoshikazu Ohya
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8562, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo 113-8657, Japan
| | - Farzan Ghanegolmohammadi
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8562, Japan
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Kaori Itto-Nakama
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8562, Japan
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Wang K, Okada H, Wloka C, Bi E. Unraveling the mechanisms and evolution of a two-domain module in IQGAP proteins for controlling eukaryotic cytokinesis. Cell Rep 2023; 42:113510. [PMID: 38041816 PMCID: PMC10809011 DOI: 10.1016/j.celrep.2023.113510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 08/17/2023] [Accepted: 11/13/2023] [Indexed: 12/04/2023] Open
Abstract
The IQGAP family of proteins plays a crucial role in cytokinesis across diverse organisms, but the underlying mechanisms are not fully understood. In this study, we demonstrate that IQGAPs in budding yeast, fission yeast, and human cells use a two-domain module to regulate their localization as well as the assembly and disassembly of the actomyosin ring during cytokinesis. Strikingly, the calponin homology domains (CHDs) in these IQGAPs bind to distinct cellular F-actin structures with varying specificity, whereas the non-conserved domains immediately downstream of the CHDs in these IQGAPs all target the division site, but differ in timing, localization strength, and binding partners. We also demonstrate that human IQGAP3 acts in parallel to septins and myosin-IIs to mediate the role of anillin in cytokinesis. Collectively, our findings highlight the two-domain mechanism by which IQGAPs regulate cytokinesis in distantly related organisms as well as their evolutionary conservation and divergence.
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Affiliation(s)
- Kangji Wang
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Hiroki Okada
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA
| | - Carsten Wloka
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA; Experimental Ophthalmology, Department of Ophthalmology, Charité - Universitätsmedizin Berlin, A Corporate Member of Freie Universität, Humboldt-University, The Berlin Institute of Health, Berlin, Germany
| | - Erfei Bi
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6058, USA.
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Zhang X, Fawwal DV, Spangle JM, Corbett AH, Jones CY. Exploring the Molecular Underpinnings of Cancer-Causing Oncohistone Mutants Using Yeast as a Model. J Fungi (Basel) 2023; 9:1187. [PMID: 38132788 PMCID: PMC10744705 DOI: 10.3390/jof9121187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 11/27/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023] Open
Abstract
Understanding the molecular basis of cancer initiation and progression is critical in developing effective treatment strategies. Recently, mutations in genes encoding histone proteins that drive oncogenesis have been identified, converting these essential proteins into "oncohistones". Understanding how oncohistone mutants, which are commonly single missense mutations, subvert the normal function of histones to drive oncogenesis requires defining the functional consequences of such changes. Histones genes are present in multiple copies in the human genome with 15 genes encoding histone H3 isoforms, the histone for which the majority of oncohistone variants have been analyzed thus far. With so many wildtype histone proteins being expressed simultaneously within the oncohistone, it can be difficult to decipher the precise mechanistic consequences of the mutant protein. In contrast to humans, budding and fission yeast contain only two or three histone H3 genes, respectively. Furthermore, yeast histones share ~90% sequence identity with human H3 protein. Its genetic simplicity and evolutionary conservation make yeast an excellent model for characterizing oncohistones. The power of genetic approaches can also be exploited in yeast models to define cellular signaling pathways that could serve as actionable therapeutic targets. In this review, we focus on the value of yeast models to serve as a discovery tool that can provide mechanistic insights and inform subsequent translational studies in humans.
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Affiliation(s)
- Xinran Zhang
- Department of Biology, Emory University, Atlanta, GA 30322, USA; (X.Z.); (D.V.F.); (A.H.C.)
| | - Dorelle V. Fawwal
- Department of Biology, Emory University, Atlanta, GA 30322, USA; (X.Z.); (D.V.F.); (A.H.C.)
- Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Biochemistry, Cell & Developmental Biology Graduate Program, Emory University, Atlanta, GA 30322, USA
| | - Jennifer M. Spangle
- Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Anita H. Corbett
- Department of Biology, Emory University, Atlanta, GA 30322, USA; (X.Z.); (D.V.F.); (A.H.C.)
- Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Celina Y. Jones
- Department of Biology, Emory University, Atlanta, GA 30322, USA; (X.Z.); (D.V.F.); (A.H.C.)
- Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
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12
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Dolan M, St. John N, Zaidi F, Doyle F, Fasullo M. High-throughput screening of the Saccharomyces cerevisiae genome for 2-amino-3-methylimidazo [4,5-f] quinoline resistance identifies colon cancer-associated genes. G3 (Bethesda) 2023; 13:jkad219. [PMID: 37738679 PMCID: PMC11025384 DOI: 10.1093/g3journal/jkad219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 10/25/2022] [Accepted: 09/15/2023] [Indexed: 09/24/2023]
Abstract
Heterocyclic aromatic amines (HAAs) are potent carcinogenic agents found in charred meats and cigarette smoke. However, few eukaryotic resistance genes have been identified. We used Saccharomyces cerevisiae (budding yeast) to identify genes that confer resistance to 2-amino-3-methylimidazo[4,5-f] quinoline (IQ). CYP1A2 and NAT2 activate IQ to become a mutagenic nitrenium compound. Deletion libraries expressing human CYP1A2 and NAT2 or no human genes were exposed to either 400 or 800 µM IQ for 5 or 10 generations. DNA barcodes were sequenced using the Illumina HiSeq 2500 platform and statistical significance was determined for exactly matched barcodes. We identified 424 ORFs, including 337 genes of known function, in duplicate screens of the "humanized" collection for IQ resistance; resistance was further validated for a select group of 51 genes by growth curves, competitive growth, or trypan blue assays. Screens of the library not expressing human genes identified 143 ORFs conferring resistance to IQ per se. Ribosomal protein and protein modification genes were identified as IQ resistance genes in both the original and "humanized" libraries, while nitrogen metabolism, DNA repair, and growth control genes were also prominent in the "humanized" library. Protein complexes identified included the casein kinase 2 (CK2) and histone chaperone (HIR) complex. Among DNA Repair and checkpoint genes, we identified those that function in postreplication repair (RAD18, UBC13, REV7), base excision repair (NTG1), and checkpoint signaling (CHK1, PSY2). These studies underscore the role of ribosomal protein genes in conferring IQ resistance, and illuminate DNA repair pathways for conferring resistance to activated IQ.
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Affiliation(s)
- Michael Dolan
- College of Nanotechnology, Science, and Engineering, State University of NewYork at Albany, Albany, NY 12203, USA
| | - Nick St. John
- College of Nanotechnology, Science, and Engineering, State University of NewYork at Albany, Albany, NY 12203, USA
| | - Faizan Zaidi
- College of Nanotechnology, Science, and Engineering, State University of NewYork at Albany, Albany, NY 12203, USA
| | - Francis Doyle
- College of Nanotechnology, Science, and Engineering, State University of NewYork at Albany, Albany, NY 12203, USA
| | - Michael Fasullo
- College of Nanotechnology, Science, and Engineering, State University of NewYork at Albany, Albany, NY 12203, USA
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13
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Li S, Garcia-Rodriguez LJ, Tanaka TU. Chromosome biorientation requires Aurora B's spatial separation from its outer kinetochore substrates, but not its turnover at kinetochores. Curr Biol 2023; 33:4557-4569.e3. [PMID: 37788666 DOI: 10.1016/j.cub.2023.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 08/14/2023] [Accepted: 09/01/2023] [Indexed: 10/05/2023]
Abstract
For correct chromosome segregation in mitosis, sister kinetochores must interact with microtubules from opposite spindle poles (biorientation). For this, aberrant kinetochore-microtubule interaction must be resolved (error correction) by Aurora B kinase. Once biorientation is formed, tension is applied on kinetochore-microtubule interaction, stabilizing this interaction. The mechanism for this tension-dependent process has been debated. Here, we study how Aurora B localizations at different kinetochore sites affect the biorientation establishment and maintenance in budding yeast. Without the physiological Aurora B-INCENP recruitment mechanisms, engineered recruitment of Aurora B-INCENP to the inner kinetochore, but not to the outer kinetochore, prior to biorientation supports the subsequent biorientation establishment. Moreover, when the physiological Aurora B-INCENP recruitment mechanisms are present, an engineered Aurora B-INCENP recruitment to the outer kinetochore, but not to the inner kinetochore, during metaphase (after biorientation establishment) disrupts biorientation, which is dependent on the Aurora B kinase activity. These results suggest that the spatial separation of Aurora B from its outer kinetochore substrates is required to stabilize kinetochore-microtubule interaction when biorientation is formed and tension is applied on this interaction. Meanwhile, Aurora B exhibits dynamic turnover on the centromere/kinetochore during early mitosis, a process thought to be crucial for error correction and biorientation. However, using the engineered Aurora B-INCENP recruitment to the inner kinetochore, we demonstrate that, even without such a turnover, Aurora B-INCENP can efficiently support biorientation. Our study provides important insights into how Aurora B promotes error correction for biorientation in a tension-dependent manner.
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Affiliation(s)
- Shuyu Li
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Luis J Garcia-Rodriguez
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Tomoyuki U Tanaka
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
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14
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Joshua IM, Lin M, Mardjuki A, Mazzola A, Höfken T. A Protein-Protein Interaction Analysis Suggests a Wide Range of New Functions for the p21-Activated Kinase (PAK) Ste20. Int J Mol Sci 2023; 24:15916. [PMID: 37958899 PMCID: PMC10647699 DOI: 10.3390/ijms242115916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023] Open
Abstract
The p21-activated kinases (PAKs) are important signaling proteins. They contribute to a surprisingly wide range of cellular processes and play critical roles in a number of human diseases including cancer, neurological disorders and cardiac diseases. To get a better understanding of PAK functions, mechanisms and integration of various cellular activities, we screened for proteins that bind to the budding yeast PAK Ste20 as an example, using the split-ubiquitin technique. We identified 56 proteins, most of them not described previously as Ste20 interactors. The proteins fall into a small number of functional categories such as vesicle transport and translation. We analyzed the roles of Ste20 in glucose metabolism and gene expression further. Ste20 has a well-established role in the adaptation to changing environmental conditions through the stimulation of mitogen-activated protein kinase (MAPK) pathways which eventually leads to transcription factor activation. This includes filamentous growth, an adaptation to nutrient depletion. Here we show that Ste20 also induces filamentous growth through interaction with nuclear proteins such as Sac3, Ctk1 and Hmt1, key regulators of gene expression. Combining our observations and the data published by others, we suggest that Ste20 has several new and unexpected functions.
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Affiliation(s)
| | - Meng Lin
- Institute of Biochemistry, Kiel University, 24118 Kiel, Germany
| | - Ariestia Mardjuki
- Division of Biosciences, Brunel University London, Uxbridge UB8 3PH, UK; (I.M.J.)
| | - Alessandra Mazzola
- Division of Biosciences, Brunel University London, Uxbridge UB8 3PH, UK; (I.M.J.)
- Department of Biopathology and Medical and Forensic Biotechnologies, University of Palermo, 90133 Palermo, Italy
| | - Thomas Höfken
- Division of Biosciences, Brunel University London, Uxbridge UB8 3PH, UK; (I.M.J.)
- Institute of Biochemistry, Kiel University, 24118 Kiel, Germany
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15
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Gao X, Zhou P, Li F. The multiple activations in budding yeast S-phase checkpoint are Poisson processes. PNAS Nexus 2023; 2:pgad342. [PMID: 37941810 PMCID: PMC10629469 DOI: 10.1093/pnasnexus/pgad342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 10/11/2023] [Indexed: 11/10/2023]
Abstract
Eukaryotic cells activate the S-phase checkpoint signal transduction pathway in response to DNA replication stress. Affected by the noise in biochemical reactions, such activation process demonstrates cell-to-cell variability. Here, through the analysis of microfluidics-integrated time-lapse imaging, we found multiple S-phase checkpoint activations in a certain budding yeast cell cycle. Yeast cells not only varied in their activation moments but also differed in the number of activations within the cell cycle, resulting in a stochastic multiple activation process. By investigating dynamics at the single-cell level, we showed that stochastic waiting times between consecutive activations are exponentially distributed and independent from each other. Finite DNA replication time provides a robust upper time limit to the duration of multiple activations. The mathematical model, together with further experimental evidence from the mutant strain, revealed that the number of activations under different levels of replication stress agreed well with Poisson distribution. Therefore, the activation events of S-phase checkpoint meet the criterion of Poisson process during DNA replication. In sum, the observed Poisson activation process may provide new insights into the complex stochastic dynamics of signal transduction pathways.
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Affiliation(s)
- Xin Gao
- School of Physics, Center for Quantitative Biology, Peking University, Beijing 100871, China
| | - Peijie Zhou
- Department of Mathematics, University of California, Irvine, CA 92697, USA
| | - Fangting Li
- School of Physics, Center for Quantitative Biology, Peking University, Beijing 100871, China
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16
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Li YM, Mei YC, Liu AH, Wang RX, Chen R, Du HN. Gcn5- and Bre1-mediated Set2 degradation promotes chronological aging of Saccharomyces cerevisiae. Cell Rep 2023; 42:113186. [PMID: 37796660 DOI: 10.1016/j.celrep.2023.113186] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 07/19/2023] [Accepted: 09/13/2023] [Indexed: 10/07/2023] Open
Abstract
Loss of transcription-coupled histone H3 lysine 36 trimethylation (H3K36me3) contributes to shorter lifespans in eukaryotes. However, the molecular mechanism of the decline of H3K36me3 during aging remains poorly understood. Here, we report that the degradation of the methyltransferase Set2 is the cause of decreased H3K36me3 levels during chronological aging in budding yeast. We show that Set2 protein degradation during cellular senescence and chronological aging is mainly mediated by the ubiquitin-conjugating E2 enzyme Ubc3 and the E3 ligase Bre1. Lack of Bre1 or abolishment of the ubiquitination stabilizes Set2 protein, sustains H3K36me3 levels at the aging-related gene loci, and upregulates their gene expression, thus leading to extended chronological lifespan. We further illustrate that Gcn5-mediated Set2 acetylation is a prerequisite for Bre1-catalyzed Set2 polyubiquitination and proteolysis during aging. We propose that two sequential post-translational modifications regulate Set2 homeostasis, suggesting a potential strategy to target the Gcn5-Bre1-Set2 axis for intervention of longevity.
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Affiliation(s)
- Yu-Min Li
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Frontier Science Center for Immunology and Metabolism, Hubei Clinical Research Center of Emergency and Resuscitation, Emergency Center of Zhongnan Hospital, RNA Institute, Wuhan University, Wuhan 430072, China
| | - Yu-Chao Mei
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Frontier Science Center for Immunology and Metabolism, Hubei Clinical Research Center of Emergency and Resuscitation, Emergency Center of Zhongnan Hospital, RNA Institute, Wuhan University, Wuhan 430072, China
| | - Ao-Hui Liu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Frontier Science Center for Immunology and Metabolism, Hubei Clinical Research Center of Emergency and Resuscitation, Emergency Center of Zhongnan Hospital, RNA Institute, Wuhan University, Wuhan 430072, China
| | - Ru-Xin Wang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Frontier Science Center for Immunology and Metabolism, Hubei Clinical Research Center of Emergency and Resuscitation, Emergency Center of Zhongnan Hospital, RNA Institute, Wuhan University, Wuhan 430072, China
| | - Runfa Chen
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Frontier Science Center for Immunology and Metabolism, Hubei Clinical Research Center of Emergency and Resuscitation, Emergency Center of Zhongnan Hospital, RNA Institute, Wuhan University, Wuhan 430072, China
| | - Hai-Ning Du
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Frontier Science Center for Immunology and Metabolism, Hubei Clinical Research Center of Emergency and Resuscitation, Emergency Center of Zhongnan Hospital, RNA Institute, Wuhan University, Wuhan 430072, China.
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17
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Foltman M, Sanchez-Diaz A. TOR Complex 1: Orchestrating Nutrient Signaling and Cell Cycle Progression. Int J Mol Sci 2023; 24:15745. [PMID: 37958727 PMCID: PMC10647266 DOI: 10.3390/ijms242115745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
The highly conserved TOR signaling pathway is crucial for coordinating cellular growth with the cell cycle machinery in eukaryotes. One of the two TOR complexes in budding yeast, TORC1, integrates environmental cues and promotes cell growth. While cells grow, they need to copy their chromosomes, segregate them in mitosis, divide all their components during cytokinesis, and finally physically separate mother and daughter cells to start a new cell cycle apart from each other. To maintain cell size homeostasis and chromosome stability, it is crucial that mechanisms that control growth are connected and coordinated with the cell cycle. Successive periods of high and low TORC1 activity would participate in the adequate cell cycle progression. Here, we review the known molecular mechanisms through which TORC1 regulates the cell cycle in the budding yeast Saccharomyces cerevisiae that have been extensively used as a model organism to understand the role of its mammalian ortholog, mTORC1.
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Affiliation(s)
- Magdalena Foltman
- Mechanisms and Regulation of Cell Division Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, 39011 Santander, Spain
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, 39011 Santander, Spain
| | - Alberto Sanchez-Diaz
- Mechanisms and Regulation of Cell Division Research Unit, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, 39011 Santander, Spain
- Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, 39011 Santander, Spain
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18
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Kobayashi N, Nishikawa SI. Nuclear Fusion in Yeast and Plant Reproduction. Plants (Basel) 2023; 12:3608. [PMID: 37896071 PMCID: PMC10609895 DOI: 10.3390/plants12203608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/09/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023]
Abstract
Nuclear fusion is essential for the sexual reproduction of various organisms, including plants, animals, and fungi. During the life cycle of flowering plants, nuclear fusion occurs three times: once during female gametogenesis and twice during double fertilization, when two sperm cells fertilize the egg and the central cell. Haploid nuclei migrate in an actin filament-dependent manner to become in close contact and, then, two nuclei fuse. The nuclear fusion process in plant reproduction is achieved through sequential nuclear membrane fusion events. Recent molecular genetic analyses using Arabidopsis thaliana showed the conservation of nuclear membrane fusion machinery between plants and the budding yeast Saccharomyces cerevisiae. These include the heat-shock protein 70 in the endoplasmic reticulum and the conserved nuclear membrane proteins. Analyses of the A. thaliana mutants of these components show that the completion of the sperm nuclear fusion at fertilization is essential for proper embryo and endosperm development.
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Affiliation(s)
- Nanami Kobayashi
- Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan;
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19
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Itriago H, Marufee Islam Z, Cohn M. Characterization of the RAD52 Gene in the Budding Yeast Naumovozyma castellii. Genes (Basel) 2023; 14:1908. [PMID: 37895257 PMCID: PMC10606518 DOI: 10.3390/genes14101908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 09/29/2023] [Accepted: 09/30/2023] [Indexed: 10/29/2023] Open
Abstract
Several sources of DNA damage compromise the integrity and stability of the genome of every organism. Specifically, DNA double-strand breaks (DSBs) can have lethal consequences for the cell. To repair this type of DNA damage, the cells employ homology-directed repair pathways or non-homologous end joining. Homology-directed repair requires the activity of the RAD52 epistasis group of genes. Rad52 is the main recombination protein in the budding yeast Saccharomyces cerevisiae, and rad52Δ mutants have been characterized to show severe defects in DSB repair and other recombination events. Here, we identified the RAD52 gene in the budding yeast Naumovozyma castellii. Our analysis showed that the primary amino acid sequence of N. castellii Rad52 shared 70% similarity with S. cerevisiae Rad52. To characterize the gene function, we developed rad52Δ mutant strains by targeted gene replacement transformation. We found that N. castellii rad52Δ mutants showed lowered growth capacity, a moderately altered cell morphology and increased sensitivity to genotoxic agents. The decreased viability of the N. castellii rad52Δ mutants in the presence of genotoxic agents indicates that the role of the Rad52 protein in the repair of DNA damage is conserved in this species.
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Affiliation(s)
| | | | - Marita Cohn
- Department of Biology, Genetics Group, Lund University, Sölvegatan 35, SE-223 62 Lund, Sweden
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20
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Abstract
Meiosis is a specialized cell division program that is essential for sexual reproduction. The two meiotic divisions reduce chromosome number by half, typically generating haploid genomes that are packaged into gametes. To achieve this ploidy reduction, meiosis relies on highly unusual chromosomal processes including the pairing of homologous chromosomes, assembly of the synaptonemal complex, programmed formation of DNA breaks followed by their processing into crossovers, and the segregation of homologous chromosomes during the first meiotic division. These processes are embedded in a carefully orchestrated cell differentiation program with multiple interdependencies between DNA metabolism, chromosome morphogenesis, and waves of gene expression that together ensure the correct number of chromosomes is delivered to the next generation. Studies in the budding yeast Saccharomyces cerevisiae have established essentially all fundamental paradigms of meiosis-specific chromosome metabolism and have uncovered components and molecular mechanisms that underlie these conserved processes. Here, we provide an overview of all stages of meiosis in this key model system and highlight how basic mechanisms of genome stability, chromosome architecture, and cell cycle control have been adapted to achieve the unique outcome of meiosis.
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Affiliation(s)
- G Valentin Börner
- Center for Gene Regulation in Health and Disease (GRHD), Department of Biological, Geological and Environmental Sciences, Cleveland State University, Cleveland, OH 44115, USA
| | | | - Amy J MacQueen
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT 06459, USA
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21
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Hwang GJH, Clyne RK. Long non-coding RNA and ribosomal protein genes in a yeast ageing model: an investigation for undergraduate research-based learning. Essays Biochem 2023; 67:893-901. [PMID: 37655454 DOI: 10.1042/ebc20230010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 09/02/2023]
Abstract
The unicellular yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe are widely used eukaryotic model organisms. Research exploiting the tractability of these model systems has contributed significantly to our understanding of a wide range of fundamental processes. In this article, we outline the features of yeast that have similarly been exploited for undergraduate research training. We selected examples from published literature that demonstrate the utility of the yeast system for research-based learning embedded in the curriculum. We further describe a project which we designed for the team-based final-year dissertation projects module on our transnational joint programme, which investigates whether the expression and functions of the budding yeast RPL36 ribosomal protein paralogs are influenced by the overlapping long non-coding RNA genes. Students carry out the experimental procedures in a 2-week timetabled teaching block and exercise widely applicable biochemical techniques, including aseptic yeast cell culture and sample collection, RNA isolation, qRT-PCR quantitation, protein extraction and Western blot analysis, and cell cycle progression patterns using light microscopy and flow cytometry. It is challenging to design training programmes for undergraduates that are meaningful as well as practical and economical, but it is possible to transform active research projects into authentic research experiences. We consider yeast to be an ideal model organism for such projects. These can be adapted to the constraints of course schedules and explore fundamental biochemical topics which are evolutionarily conserved from yeast to mammals.
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Affiliation(s)
- Gwo-Jiunn H Hwang
- Nanchang University - Queen Mary University of London Joint Programme, Nanchang University, Nanchang, Jiangxi 330036, China
| | - Rosemary K Clyne
- School of Biological and Behavioural Sciences, Nanchang University Joint Programme in Biomedical Sciences, Queen Mary University of London, London, U.K
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22
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Arend M, Ütkür K, Hawer H, Mayer K, Ranjan N, Adrian L, Brinkmann U, Schaffrath R. Yeast gene KTI13 (alias DPH8) operates in the initiation step of diphthamide synthesis on elongation factor 2. Microb Cell 2023; 10:195-203. [PMID: 37662670 PMCID: PMC10468694 DOI: 10.15698/mic2023.09.804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/31/2023] [Accepted: 08/07/2023] [Indexed: 09/05/2023]
Abstract
In yeast, Elongator-dependent tRNA modifications are regulated by the Kti11•Kti13 dimer and hijacked for cell killing by zymocin, a tRNase ribotoxin. Kti11 (alias Dph3) also controls modification of elongation factor 2 (EF2) with diphthamide, the target for lethal ADP-ribosylation by diphtheria toxin (DT). Diphthamide formation on EF2 involves four biosynthetic steps encoded by the DPH1-DPH7 network and an ill-defined KTI13 function. On further examining the latter gene in yeast, we found that kti13Δ null-mutants maintain unmodified EF2 able to escape ADP-ribosylation by DT and to survive EF2 inhibition by sordarin, a diphthamide-dependent antifungal. Consistently, mass spectrometry shows kti13Δ cells are blocked in proper formation of amino-carboxyl-propyl-EF2, the first diphthamide pathway intermediate. Thus, apart from their common function in tRNA modification, both Kti11/Dph3 and Kti13 share roles in the initiation step of EF2 modification. We suggest an alias KTI13/DPH8 nomenclature indicating dual-functionality analogous to KTI11/DPH3.
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Affiliation(s)
- Meike Arend
- Institute of Biology, Division of Microbiology, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Koray Ütkür
- Institute of Biology, Division of Microbiology, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Harmen Hawer
- Institute of Biology, Division of Microbiology, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Klaus Mayer
- Roche Pharma Research & Early Development, Large Molecule Research, Roche Innovation Center München, Nonnenwald 2, 82377 Penzberg, Germany
| | - Namit Ranjan
- Max-Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Lorenz Adrian
- Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, 04318 Leipzig, Germany
| | - Ulrich Brinkmann
- Roche Pharma Research & Early Development, Large Molecule Research, Roche Innovation Center München, Nonnenwald 2, 82377 Penzberg, Germany
| | - Raffael Schaffrath
- Institute of Biology, Division of Microbiology, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
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23
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Krause DJ. The evolution of anaerobic growth in Saccharomycotina yeasts. Yeast 2023; 40:395-400. [PMID: 37526396 DOI: 10.1002/yea.3890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 06/26/2023] [Accepted: 07/18/2023] [Indexed: 08/02/2023] Open
Abstract
Humans rely on the ability of budding yeasts to grow without oxygen in industrial scale fermentations that produce beverages, foods, and biofuels. Oxygen is deeply woven into the energy metabolism and biosynthetic capabilities of budding yeasts. While diverse ecological habitats may provide wide varieties of different carbon and nitrogen sources for yeasts to utilize, there is no direct substitute for molecular oxygen, only a range of availability. Understanding how a small subset of budding yeasts evolved the ability to grow without oxygen could expand the set of useful species in industrial scale fermentations as well as provide insight into the cryptic field of yeast ecology. However, we still do not yet appreciate the full breadth of species that can growth without oxygen, what genes underlie this adaptation, and how these genes have evolved.
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Affiliation(s)
- David J Krause
- Department of Biology, University of Wisconsin Oshkosh, Oshkosh, Wisconsin, USA
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24
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Ns VS, N P, Gunabooshanam B, As P, S PK. Cytological Diagnosis Suggesting Candidal Infection of the Nasolacrimal Duct in an Uncontrolled Diabetic Patient With Gingival Abscess. Cureus 2023; 15:e44257. [PMID: 37772241 PMCID: PMC10526841 DOI: 10.7759/cureus.44257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2023] [Indexed: 09/30/2023] Open
Abstract
In this unique cytology case of a 64-year-old diabetic male who presented with left-sided facial swelling between the ala and lateral canthus of the left eye, conventional fine-needle aspiration cytology (FNAC) was done. FNAC of the swelling showed desquamated epithelial cells from the nasolacrimal duct and abundant proteinaceous material admixed with fungal organisms like that of budding yeast forms, morphologically resembling Candida on May-Grunwald-Giemsa stain. Special stain with periodic acid-Schiff revealed positivity for budding yeast forms. In this case report, we discuss the causes and clinical effects of nasolacrimal duct obstruction, cytological diagnostic features, and microscopic recognition of fungal organisms on routine staining as well as on special fungal stains.
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Affiliation(s)
- Veda Samhitha Ns
- Department of Pathology, Sri Ramachandra Institute of Higher Education and Research, Chennai, IND
| | - Priyathersini N
- Department of Pathology, Sri Ramachandra Institute of Higher Education and Research, Chennai, IND
| | - Barathi Gunabooshanam
- Department of Pathology, Sri Ramachandra Institute of Higher Education and Research, Chennai, IND
| | - Ponneyinchelvi As
- Department of Pathology, Sri Ramachandra Institute of Higher Education and Research, Chennai, IND
| | - Prasanna Kumar S
- Department of Otorhinolaryngology, Sri Ramachandra Institute of Higher Education and Research, Chennai, IND
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25
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Boronat S, Cabrera M, Vega M, Alcalá J, Salas-Pino S, Daga RR, Ayté J, Hidalgo E. Formation of Transient Protein Aggregate-like Centers Is a General Strategy Postponing Degradation of Misfolded Intermediates. Int J Mol Sci 2023; 24:11202. [PMID: 37446379 DOI: 10.3390/ijms241311202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023] Open
Abstract
When misfolded intermediates accumulate during heat shock, the protein quality control system promotes cellular adaptation strategies. In Schizosaccharomyces pombe, thermo-sensitive proteins assemble upon stress into protein aggregate-like centers, PACs, to escape from degradation. The role of this protein deposition strategy has been elusive due to the use of different model systems and reporters, and to the addition of artificial inhibitors, which made interpretation of the results difficult. Here, we compare fission and budding yeast model systems, expressing the same misfolding reporters in experiments lacking proteasome or translation inhibitors. We demonstrate that mild heat shock triggers reversible PAC formation, with the collapse of both reporters and chaperones in a process largely mediated by chaperones. This assembly postpones proteasomal degradation of the misfolding reporters, and their Hsp104-dependent disassembly occurs during stress recovery. Severe heat shock induces formation of cytosolic PACs, but also of nuclear structures resembling nucleolar rings, NuRs, presumably to halt nuclear functions. Our study demonstrates that these distantly related yeasts use very similar strategies to adapt and survive to mild and severe heat shock and that aggregate-like formation is a general cellular scheme to postpone protein degradation and facilitate exit from stress.
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Affiliation(s)
- Susanna Boronat
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/Doctor Aiguader 88, 08003 Barcelona, Spain
| | - Margarita Cabrera
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/Doctor Aiguader 88, 08003 Barcelona, Spain
- Centro de Biología Molecular Severo Ochoa and Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), 28049 Madrid, Spain
| | - Montserrat Vega
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/Doctor Aiguader 88, 08003 Barcelona, Spain
| | - Jorge Alcalá
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/Doctor Aiguader 88, 08003 Barcelona, Spain
| | - Silvia Salas-Pino
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas-Junta de Andalucía, Carretera de Utrera, km1, 41013 Seville, Spain
| | - Rafael R Daga
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas-Junta de Andalucía, Carretera de Utrera, km1, 41013 Seville, Spain
| | - José Ayté
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/Doctor Aiguader 88, 08003 Barcelona, Spain
| | - Elena Hidalgo
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/Doctor Aiguader 88, 08003 Barcelona, Spain
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Nishimura Y, Okuda M. Structural polymorphism of the PH domain in TFIIH. Biosci Rep 2023:BSR20230846. [PMID: 37340985 PMCID: PMC10345426 DOI: 10.1042/bsr20230846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 05/30/2023] [Accepted: 06/20/2023] [Indexed: 06/22/2023] Open
Abstract
The general transcription factor TFIIH is a multi-subunit complex involved in transcription, DNA repair, and cell cycle in eukaryotes. In the human p62 subunit and the budding yeast Saccharomyces cerevisiae Tfb1 subunit of TFIIH, the pleckstrin homology (PH) domain (hPH/scPH) recruits TFIIH to transcription-start and DNA-damage sites by interacting with an acidic intrinsically disordered region in transcription and repair factors. Whereas metazoan PH domains are highly conserved and adopt a similar structure, fungal PH domains are divergent and only the scPH structure is available. Here, we have determined the structure of the PH domain from Tfb1 of fission yeast Schizosaccharomyces pombe (spPH) by NMR. spPH holds an architecture, including the core and external backbone structures, that is closer to hPH than to scPH despite having higher amino acid sequence identity to scPH. In addition, the predicted target-binding site of spPH shares more amino acid similarity with scPH, but spPH contains several key residues identified in hPH as required for specific binding. Using chemical shift perturbation, we have identified binding modes of spPH to spTfa1, a homologue of hTFIIEα, and to spRhp41, a homologue of the repair factors hXPC and scRad4. Both spTfa1 and spRhp41 bind to a similar but distinct surface of spPH by modes that differ from those of target proteins binding to hPH and scPH, revealing that the PH domain of TFIIH interacts with its target proteins in a polymorphic manner in Metazoa, and budding and fission yeasts.
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González-Rubio G, Martín H, Molina M. The Mitogen-Activated Protein Kinase Slt2 Promotes Asymmetric Cell Cycle Arrest and Reduces TORC1-Sch9 Signaling in Yeast Lacking the Protein Phosphatase Ptc1. Microbiol Spectr 2023; 11:e0524922. [PMID: 37042757 PMCID: PMC10269544 DOI: 10.1128/spectrum.05249-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 03/18/2023] [Indexed: 04/13/2023] Open
Abstract
Mitogen-activated protein kinase (MAPK) pathways regulate essential processes in eukaryotes. However, since uncontrolled activation of these cascades has deleterious effects, precise negative regulation of signaling flow through them, mainly executed by protein phosphatases, is crucial. Previous studies showed that the absence of Ptc1 protein phosphatase results in the upregulation of the MAPK of the cell wall integrity (CWI) pathway, Slt2, and numerous functional defects in Saccharomyces cerevisiae, including a failure to undergo cell separation under heat stress. In this study, we demonstrate that multibudded ptc1Δ cells also exhibit impaired mitochondrial inheritance and that excessive Slt2 kinase activity is responsible for their growth deficiency and daughter-specific G1 cell cycle arrest, as well as other physiological alterations, namely, mitochondrial hyperpolarization and reactive oxygen species (ROS) accumulation. We bring to light the fact that sustained Slt2 kinase activity inhibits signaling through the Sch9 branch of the TORC1 pathway in ptc1Δ cells, leading to increased autophagy. After cytokinesis, septin rings asymmetrically disassembled in ptc1Δ multibudded cells, abnormally remaining at the daughter cell side and eventually relocalizing at the daughter cell periphery, where they occasionally colocalized with the autophagic protein Atg9. Finally, we show that the inability of ptc1Δ cells to undergo cell separation is not due to a failure in the regulation of Ace2 and morphogenesis (RAM) pathway, since the transcription factor Ace2 correctly enters the daughter cell nuclei. However, the Ace2-regulated endochitinase Cts1 did not localize to the septum, preventing the proper degradation of this structure. IMPORTANCE This study provides further evidence that the cell cycle is regulated by complex signaling networks whose purpose is to guarantee a robust response to environmental threats. Using the S. cerevisiae eukaryotic model, we show that, under the stress conditions that activate the CWI MAPK pathway, the absence of the protein phosphatase Ptc1 renders Slt2 hyperactive, leading to numerous physiological alterations, including perturbed mitochondrial inheritance, oxidative stress, changes in septin dynamics, increased autophagy, TORC1-Sch9 inhibition, and ultimately cell cycle arrest and the failure of daughter cells to separate, likely due to the absence of key degradative enzymes at the septum. These results imply novel roles for the CWI pathway and unravel new cell cycle-regulatory controls that operate beyond the RAM pathway, arresting buds in G1 without compromising further division rounds in the mother cell.
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Affiliation(s)
- Gema González-Rubio
- Departamento de Microbiología y Parasitología. Facultad de Farmacia. Instituto Ramón y Cajal de Investigaciones Sanitarias, Universidad Complutense de Madrid, Madrid, Spain
| | - Humberto Martín
- Departamento de Microbiología y Parasitología. Facultad de Farmacia. Instituto Ramón y Cajal de Investigaciones Sanitarias, Universidad Complutense de Madrid, Madrid, Spain
| | - María Molina
- Departamento de Microbiología y Parasitología. Facultad de Farmacia. Instituto Ramón y Cajal de Investigaciones Sanitarias, Universidad Complutense de Madrid, Madrid, Spain
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Opalek M, Tutaj H, Pirog A, Smug BJ, Rutkowska J, Wloch-Salamon D. A Systematic Review on Quiescent State Research Approaches in S. cerevisiae. Cells 2023; 12:1608. [PMID: 37371078 DOI: 10.3390/cells12121608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/02/2023] [Accepted: 06/09/2023] [Indexed: 06/29/2023] Open
Abstract
Quiescence, the temporary and reversible arrest of cell growth, is a fundamental biological process. However, the lack of standardization in terms of reporting the experimental details of quiescent cells and populations can cause confusion and hinder knowledge transfer. We employ the systematic review methodology to comprehensively analyze the diversity of approaches used to study the quiescent state, focusing on all published research addressing the budding yeast Saccharomyces cerevisiae. We group research articles into those that consider all cells comprising the stationary-phase (SP) population as quiescent and those that recognize heterogeneity within the SP by distinguishing phenotypically distinct subpopulations. Furthermore, we investigate the chronological age of the quiescent populations under study and the methods used to induce the quiescent state, such as gradual starvation or abrupt environmental change. We also assess whether the strains used in research are prototrophic or auxotrophic. By combining the above features, we identify 48 possible experimental setups that can be used to study quiescence, which can be misleading when drawing general conclusions. We therefore summarize our review by proposing guidelines and recommendations pertaining to the information included in research articles. We believe that more rigorous reporting on the features of quiescent populations will facilitate knowledge transfer within and between disciplines, thereby stimulating valuable scientific discussion.
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Affiliation(s)
- Monika Opalek
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Hanna Tutaj
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Adrian Pirog
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Bogna J Smug
- Malopolska Centre of Biotechnology, Jagiellonian University, 30-387 Krakow, Poland
| | - Joanna Rutkowska
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Dominika Wloch-Salamon
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
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29
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Farajzadeh N, Shahbabian K, Bouaziz Y, Querido E, Chartrand P. Phosphorylation controls the oligomeric state of She2 and mRNA localization in yeast. RNA 2023; 29:745-755. [PMID: 36921931 PMCID: PMC10187671 DOI: 10.1261/rna.079555.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 02/24/2023] [Indexed: 05/18/2023]
Abstract
Messenger RNA (mRNA) localization is an important mechanism controlling local protein synthesis. In budding yeast, asymmetric localization of transcripts such as ASH1 mRNA to the bud tip depends on the She2 RNA-binding protein. She2 assembles as a tetramer to bind RNA, but the regulation of this process as part of the mRNA locasome is still unclear. Here, we performed a phosphoproteomic analysis of She2 in vivo and identified new phosphosites, several of which are located at the dimerization or tetramerization interfaces of She2. Remarkably, phosphomimetic mutations at these residues disrupt the capacity of She2 to promote Ash1 asymmetric accumulation. A detailed analysis of one of these residues, T109, shows that a T109D mutation inhibits She2 oligomerization and its interaction with She3 and the importin-α Srp1. She2 proteins harboring the T109D mutation also display reduced expression. More importantly, this phosphomimetic mutation strongly impairs the capacity of She2 to bind RNA and disrupts ASH1 mRNA localization. These results demonstrate that the control of She2 oligomerization by phosphorylation constitutes an important regulatory step in the mRNA localization pathway.
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Affiliation(s)
- Nastaran Farajzadeh
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
| | - Karen Shahbabian
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
| | - Yani Bouaziz
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
| | - Emmanuelle Querido
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
| | - Pascal Chartrand
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
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Abstract
Accurate phenotype prediction based on genetic information has numerous societal applications, such as crop design or cellular factories. Epistasis, when biological components interact, complicates modelling phenotypes from genotypes. Here we show an approach to mitigate this complication for polarity establishment in budding yeast, where mechanistic information is abundant. We coarse-grain molecular interactions into a so-called mesotype, which we combine with gene expression noise into a physical cell cycle model. First, we show with computer simulations that the mesotype allows validation of the most current biochemical polarity models by quantitatively matching doubling times. Second, the mesotype elucidates epistasis emergence as exemplified by evaluating the predicted mutational effect of key polarity protein Bem1p when combined with known interactors or under different growth conditions. This example also illustrates how unlikely evolutionary trajectories can become more accessible. The tractability of our biophysically justifiable approach inspires a road-map towards bottom-up modelling complementary to statistical inferences. This article is part of the theme issue ‘Interdisciplinary approaches to predicting evolutionary biology’.
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Affiliation(s)
| | - Els Sweep
- Department of Bionanoscience, TU Delft, 2629 HZ Delft, The Netherlands
| | - Liedewij Laan
- Department of Bionanoscience, TU Delft, 2629 HZ Delft, The Netherlands
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31
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Patel HP, Coppola S, Pomp W, Aiello U, Brouwer I, Libri D, Lenstra TL. DNA supercoiling restricts the transcriptional bursting of neighboring eukaryotic genes. Mol Cell 2023; 83:1573-1587.e8. [PMID: 37207624 DOI: 10.1016/j.molcel.2023.04.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 02/14/2023] [Accepted: 04/14/2023] [Indexed: 05/21/2023]
Abstract
DNA supercoiling has emerged as a major contributor to gene regulation in bacteria, but how DNA supercoiling impacts transcription dynamics in eukaryotes is unclear. Here, using single-molecule dual-color nascent transcription imaging in budding yeast, we show that transcriptional bursting of divergent and tandem GAL genes is coupled. Temporal coupling of neighboring genes requires rapid release of DNA supercoils by topoisomerases. When DNA supercoils accumulate, transcription of one gene inhibits transcription at its adjacent genes. Transcription inhibition of the GAL genes results from destabilized binding of the transcription factor Gal4. Moreover, wild-type yeast minimizes supercoiling-mediated inhibition by maintaining sufficient levels of topoisomerases. Overall, we discover fundamental differences in transcriptional control by DNA supercoiling between bacteria and yeast and show that rapid supercoiling release in eukaryotes ensures proper gene expression of neighboring genes.
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Affiliation(s)
- Heta P Patel
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Stefano Coppola
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Wim Pomp
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Umberto Aiello
- Université Paris Cité, CNRS, Institut Jacques Monod, 75013 Paris, France
| | - Ineke Brouwer
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands
| | - Domenico Libri
- Université Paris Cité, CNRS, Institut Jacques Monod, 75013 Paris, France
| | - Tineke L Lenstra
- Division of Gene Regulation, The Netherlands Cancer Institute, Oncode Institute, 1066CX Amsterdam, the Netherlands.
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32
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Andriuskevicius T, Dubenko A, Makovets S. The Inability to Disassemble Rad51 Nucleoprotein Filaments Leads to Aberrant Mitosis and Cell Death. Biomedicines 2023; 11:biomedicines11051450. [PMID: 37239121 DOI: 10.3390/biomedicines11051450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 04/30/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
The proper maintenance of genetic material is essential for the survival of living organisms. One of the main safeguards of genome stability is homologous recombination involved in the faithful repair of DNA double-strand breaks, the restoration of collapsed replication forks, and the bypass of replication barriers. Homologous recombination relies on the formation of Rad51 nucleoprotein filaments which are responsible for the homology-based interactions between DNA strands. Here, we demonstrate that without the regulation of these filaments by Srs2 and Rad54, which are known to remove Rad51 from single-stranded and double-stranded DNA, respectively, the filaments strongly inhibit damage-associated DNA synthesis during DNA repair. Furthermore, this regulation is essential for cell survival under normal growth conditions, as in the srs2Δ rad54Δ mutants, unregulated Rad51 nucleoprotein filaments cause activation of the DNA damage checkpoint, formation of mitotic bridges, and loss of genetic material. These genome instability features may stem from the problems at stalled replication forks as the lack of Srs2 and Rad54 in the presence of Rad51 nucleoprotein filaments impedes cell recovery from replication stress. This study demonstrates that the timely and efficient disassembly of recombination machinery is essential for genome maintenance and cell survival.
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Affiliation(s)
- Tadas Andriuskevicius
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Alexander Crum Brown Road, Edinburgh EH9 3FF, UK
| | - Anton Dubenko
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Alexander Crum Brown Road, Edinburgh EH9 3FF, UK
| | - Svetlana Makovets
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Alexander Crum Brown Road, Edinburgh EH9 3FF, UK
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33
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Wong ED, Miyasato SR, Aleksander S, Karra K, Nash RS, Skrzypek MS, Weng S, Engel SR, Cherry JM. Saccharomyces genome database update: server architecture, pan-genome nomenclature, and external resources. Genetics 2023; 224:iyac191. [PMID: 36607068 PMCID: PMC10158836 DOI: 10.1093/genetics/iyac191] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 11/16/2022] [Accepted: 12/21/2022] [Indexed: 01/07/2023] Open
Abstract
As one of the first model organism knowledgebases, Saccharomyces Genome Database (SGD) has been supporting the scientific research community since 1993. As technologies and research evolve, so does SGD: from updates in software architecture, to curation of novel data types, to incorporation of data from, and collaboration with, other knowledgebases. We are continuing to make steps toward providing the community with an S. cerevisiae pan-genome. Here, we describe software upgrades, a new nomenclature system for genes not found in the reference strain, and additions to gene pages. With these improvements, we aim to remain a leading resource for students, researchers, and the broader scientific community.
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Affiliation(s)
- Edith D Wong
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Stuart R Miyasato
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Suzi Aleksander
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Kalpana Karra
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Robert S Nash
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Marek S Skrzypek
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Shuai Weng
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Stacia R Engel
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - J Michael Cherry
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
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34
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Robertson CM, Xue Y, Chowdhury S, Maringele L. A CDK-Dependent Phosphorylation of a Novel Domain of Rif1 Regulates its Function during Telomere Damage and Other Types of Stress. Mol Cell Biol 2023; 43:185-199. [PMID: 37140180 PMCID: PMC10184589 DOI: 10.1080/10985549.2023.2193768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
Rif1 mediates telomere length, DNA replication, and DNA damage responses in budding yeast. Previous work identified several posttranslational modifications of Rif1, however none of these was shown to mediate the molecular or cellular responses to DNA damage, including telomere damage. We searched for such modifications using immunoblotting methods and the cdc13-1 and tlc1Δ models of telomere damage. We found that Rif1 is phosphorylated during telomere damage, and that serines 57 and 110 within a novel phospho-gate domain (PGD) of Rif1 are important for this modification, in cdc13-1 cells. The phosphorylation of Rif1 appeared to inhibit its accumulation on damaged chromosomes and the proliferation of cells with telomere damage. Moreover, we found that checkpoint kinases were upstream of this Rif1 phosphorylation and that the Cdk1 activity was essential for maintaining it. Apart from telomere damage, S57 and S110 were essential for Rif1 phosphorylation during the treatment of cells with genotoxic agents or during mitotic stress. We propose a speculative "Pliers" model to explain the role of the PGD phosphorylation during telomere and other types of damage.
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Affiliation(s)
- Cameron M Robertson
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Yuan Xue
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Shobir Chowdhury
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Laura Maringele
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
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35
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Fan L, Zhang W, Rybchuk J, Luo Y, Xiao W. Genetic Dissection of Budding Yeast PCNA Mutations Responsible for the Regulated Recruitment of Srs2 Helicase. mBio 2023; 14:e0031523. [PMID: 36861970 PMCID: PMC10127746 DOI: 10.1128/mbio.00315-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 03/03/2023] Open
Abstract
DNA-damage tolerance (DDT) is a mechanism by which eukaryotes bypass replication-blocking lesions to resume DNA synthesis and maintain cell viability. In Saccharomyces cerevisiae, DDT is mediated by sequential ubiquitination and sumoylation of proliferating cell nuclear antigen (PCNA, encoded by POL30) at the K164 residue. Deletion of RAD5 or RAD18, encoding two ubiquitin ligases required for PCNA ubiquitination, results in severe DNA-damage sensitivity, which can be rescued by inactivation of SRS2 encoding a DNA helicase that inhibits undesired homologous recombination. In this study, we isolated DNA-damage resistant mutants from rad5Δ cells and found that one of them contained a pol30-A171D mutation, which could rescue both rad5Δ and rad18Δ DNA-damage sensitivity in a srs2-dependent and PCNA sumoylation-independent manner. Pol30-A171D abolished physical interaction with Srs2 but not another PCNA-interacting protein Rad30; however, Pol30-A171 is not located in the PCNA-Srs2 interface. The PCNA-Srs2 structure was analyzed to design and create mutations in the complex interface, one of which, pol30-I128A, resulted in phenotypes reminiscent of pol30-A171D. This study allows us to conclude that, unlike other PCNA-binding proteins, Srs2 interacts with PCNA through a partially conserved motif, and the interaction can be strengthened by PCNA sumoylation, which turns Srs2 recruitment into a regulated process. IMPORTANCE It is known that budding yeast PCNA sumoylation serves as a ligand to recruit a DNA helicase Srs2 through its tandem receptor motifs that prevent unwanted homologous recombination (HR) at replication forks, a process known as salvage HR. This study reveals detailed molecular mechanisms, in which constitutive PCNA-PIP interaction has been adapted to a regulatory event. Since both PCNA and Srs2 are highly conserved in eukaryotes, from yeast to human, this study may shed light to investigation of similar regulatory mechanisms.
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Affiliation(s)
- Li Fan
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, China
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Wenqing Zhang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, China
| | - Josephine Rybchuk
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- Toxicology Program, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Yu Luo
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Wei Xiao
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, China
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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36
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Fita-Torró J, Swamy KBS, Pascual-Ahuir A, Proft M. Divergence of alternative sugar preferences through modulation of the expression and activity of the Gal3 sensor in yeast. Mol Ecol 2023. [PMID: 37052375 DOI: 10.1111/mec.16954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/03/2023] [Accepted: 04/05/2023] [Indexed: 04/14/2023]
Abstract
Optimized nutrient utilization is crucial for the progression of microorganisms in competing communities. Here we investigate how different budding yeast species and ecological isolates have established divergent preferences for two alternative sugar substrates: Glucose, which is fermented preferentially by yeast, and galactose, which is alternatively used upon induction of the relevant GAL metabolic genes. We quantified the dose-dependent induction of the GAL1 gene encoding the central galactokinase enzyme and found that a very large diversification exists between different yeast ecotypes and species. The sensitivity of GAL1 induction correlates with the growth performance of the respective yeasts with the alternative sugar. We further define some of the mechanisms, which have established different glucose/galactose consumption strategies in representative yeast strains by modulating the activity of the Gal3 inducer. (1) Optimal galactose consumers, such as Saccharomyces uvarum, contain a hyperactive GAL3 promoter, sustaining highly sensitive GAL1 expression, which is not further improved upon repetitive galactose encounters. (2) Desensitized galactose consumers, such as S. cerevisiae Y12, contain a less sensitive Gal3 sensor, causing a shift of the galactose response towards higher sugar concentrations even in galactose experienced cells. (3) Galactose insensitive sugar consumers, such as S. cerevisiae DBVPG6044, contain an interrupted GAL3 gene, causing extremely reluctant galactose consumption, which is, however, improved upon repeated galactose availability. In summary, different yeast strains and natural isolates have evolved galactose utilization strategies, which cover the whole range of possible sensitivities by modulating the expression and/or activity of the inducible galactose sensor Gal3.
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Affiliation(s)
- Josep Fita-Torró
- Department of Molecular and Cellular Pathology and Therapy, Instituto de Biomedicina de Valencia IBV-CSIC, Valencia, Spain
| | - Krishna B S Swamy
- Division of Biological and Life Sciences, School of Arts and Sciences, Ahmedabad University, Ahmedabad, India
| | - Amparo Pascual-Ahuir
- Department of Biotechnology, Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València, Valencia, Spain
| | - Markus Proft
- Department of Molecular and Cellular Pathology and Therapy, Instituto de Biomedicina de Valencia IBV-CSIC, Valencia, Spain
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Abstract
Genome instability is a major cause of aging. In the budding yeast Saccharomyces cerevisiae, instability of the ribosomal RNA gene repeat (rDNA) is known to shorten replicative lifespan. In yeast, rDNA instability in an aging cell is associated with accumulation of extrachromosomal rDNA circles (ERCs) which titrate factors critical for lifespan maintenance. ERC accumulation is not detected in mammalian cells, where aging is linked to DNA damage. To distinguish effects of DNA damage from those of ERC accumulation on senescence, we re-analyzed a yeast strain with a replication initiation defect in the rDNA, which limits ERC multiplication. In aging cells of this strain (rARS-∆3) rDNA became unstable, as in wild-type cells, whereas significantly fewer ERCs accumulated. Single-cell aging analysis revealed that rARS-∆3 cells follow a linear survival curve and can have a wild-type replicative lifespan, although a fraction of the cells stopped dividing earlier than wild type. The doubling time of rARS-∆3 cells appears to increase in the final cell divisions. Our results suggest that senescence in rARS-∆3 is linked to the accumulation of DNA damage as in mammalian cells, rather than to elevated ERC level. Therefore, this strain should be a good model system to study ERC-independent aging.
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Affiliation(s)
- Mei Hattori
- Laboratory of Genome Regeneration, Institute for Quantitative Biosciences (IQB), The University of Tokyo.,Department of Biological Sciences, Graduate School of Science, The University of Tokyo
| | - Chihiro Horigome
- Laboratory of Genome Regeneration, Institute for Quantitative Biosciences (IQB), The University of Tokyo
| | - Théo Aspert
- Laboratoire de Génétique Moléculaire, Génomique et Microbiologie
| | - Gilles Charvin
- Laboratoire de Génétique Moléculaire, Génomique et Microbiologie
| | - Takehiko Kobayashi
- Laboratory of Genome Regeneration, Institute for Quantitative Biosciences (IQB), The University of Tokyo.,Department of Biological Sciences, Graduate School of Science, The University of Tokyo.,Collaborative Research Institute for Innovative Microbiology, The University of Tokyo
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38
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Hirai H, Ohta K. Comparative Research: Regulatory Mechanisms of Ribosomal Gene Transcription in Saccharomyces cerevisiae and Schizosaccharomyces pombe. Biomolecules 2023; 13. [PMID: 36830657 DOI: 10.3390/biom13020288] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
Restricting ribosome biosynthesis and assembly in response to nutrient starvation is a universal phenomenon that enables cells to survive with limited intracellular resources. When cells experience starvation, nutrient signaling pathways, such as the target of rapamycin (TOR) and protein kinase A (PKA), become quiescent, leading to several transcription factors and histone modification enzymes cooperatively and rapidly repressing ribosomal genes. Fission yeast has factors for heterochromatin formation similar to mammalian cells, such as H3K9 methyltransferase and HP1 protein, which are absent in budding yeast. However, limited studies on heterochromatinization in ribosomal genes have been conducted on fission yeast. Herein, we shed light on and compare the regulatory mechanisms of ribosomal gene transcription in two species with the latest insights.
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39
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Kawashima Y, Oda AH, Hikida Y, Ohta K. Chromosome-dependent aneuploid formation in Spo11-less meiosis. Genes Cells 2023; 28:129-148. [PMID: 36530025 PMCID: PMC10107155 DOI: 10.1111/gtc.12998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/21/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022]
Abstract
Deficiency in meiotic recombination leads to aberrant chromosome disjunction during meiosis, often resulting in the lethality of gametes or genetic disorders due to aneuploidy formation. Budding yeasts lacking Spo11, which is essential for initiation of meiotic recombination, produce many inviable spores in meiosis, while very rarely all sets of 16 chromosomes are coincidentally assorted into gametes to form viable spores. We induced meiosis in a spo11∆ diploid, in which homolog pairs can be distinguished by single nucleotide polymorphisms and determined whole-genome sequences of their exceptionally viable spores. We detected no homologous recombination in the viable spores of spo11∆ diploid. Point mutations were fewer in spo11∆ than in wild-type. We observed spo11∆ viable spores carrying a complete diploid set of homolog pairs or haploid spores with a complete haploid set of homologs but with aneuploidy in some chromosomes. In the latter, we found the chromosome-dependence in the aneuploid incidence, which was positively and negatively influenced by the chromosome length and the impact of dosage-sensitive genes, respectively. Selection of aneuploidy during meiosis II or mitosis after spore germination was also chromosome dependent. These results suggest a pathway by which specific chromosomes are more prone to cause aneuploidy, as observed in Down syndrome.
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Affiliation(s)
- Yuri Kawashima
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Arisa H Oda
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Yasushi Hikida
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Kunihiro Ohta
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.,Universal Biology Institute, The University of Tokyo, Tokyo, Japan
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40
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Yokoyama M, Sasaki M, Kobayashi T. Spt4 promotes cellular senescence by activating non-coding RNA transcription in ribosomal RNA gene clusters. Cell Rep 2023; 42:111944. [PMID: 36640349 DOI: 10.1016/j.celrep.2022.111944] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 07/06/2022] [Accepted: 12/19/2022] [Indexed: 01/11/2023] Open
Abstract
Genome instability can drive aging in many organisms. The ribosomal RNA gene (rDNA) cluster is one of the most unstable regions in the genome and the stability of this region impacts replicative lifespan in budding yeast. To understand the underlying mechanism, we search for yeast mutants with stabler rDNA and longer lifespans than wild-type cells. We show that absence of a transcription elongation factor, Spt4, results in increased rDNA stability, reduced levels of non-coding RNA transcripts from the regulatory E-pro promoter in the rDNA, and extended replicative lifespan in a SIR2-dependent manner. Spt4-dependent lifespan restriction is abolished in the absence of non-coding RNA transcription at the E-pro locus. The amount of Spt4 increases and its function becomes more important as cells age. These findings suggest that Spt4 is a promising aging factor that accelerates cellular senescence through rDNA instability driven by non-coding RNA transcription.
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Affiliation(s)
- Masaaki Yokoyama
- Laboratory of Genome Regeneration, Institute for Quantitative Biosciences (IQB), The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan; Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Mariko Sasaki
- Laboratory of Genome Regeneration, Institute for Quantitative Biosciences (IQB), The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan; Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Takehiko Kobayashi
- Laboratory of Genome Regeneration, Institute for Quantitative Biosciences (IQB), The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan; Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
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41
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Ibanes S, El-Alaoui F, Lai-Kee-Him J, Cazevieille C, Hoh F, Lyonnais S, Bron P, Cipelletti L, Picas L, Piatti S. The Syp1/FCHo2 protein induces septin filament bundling through its intrinsically disordered domain. Cell Rep 2022; 41:111765. [PMID: 36476870 DOI: 10.1016/j.celrep.2022.111765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 09/30/2022] [Accepted: 11/10/2022] [Indexed: 12/12/2022] Open
Abstract
The septin collar of budding yeast is an ordered array of septin filaments that serves a scaffolding function for the cytokinetic machinery at the bud neck and compartmentalizes the membrane between mother and daughter cell. How septin architecture is aided by septin-binding proteins is largely unknown. Syp1 is an endocytic protein that was implicated in the timely recruitment of septins to the newly forming collar through an unknown mechanism. Using advanced microscopy and in vitro reconstitution assays, we show that Syp1 is able to align laterally and tightly pack septin filaments, thereby forming flat bundles or sheets. This property is shared by the Syp1 mammalian counterpart FCHo2, thus emphasizing conserved protein functions. Interestingly, the septin-bundling activity of Syp1 resides mainly in its intrinsically disordered region. Our data uncover the mechanism through which Syp1 promotes septin collar assembly and offer another example of functional diversity of unstructured protein domains.
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Affiliation(s)
- Sandy Ibanes
- CRBM (Centre de Recherche en Biologie cellulaire de Montpellier), University of Montpellier, CNRS UMR 5237, 1919 Route de Mende, 34293 Montpellier, France
| | - Fatima El-Alaoui
- IRIM (Institut de Recherche en Infectiologie de Montpellier), University of Montpellier, CNRS UMR 9004, 1919 Route de Mende, 34293 Montpellier, France
| | - Joséphine Lai-Kee-Him
- CBS (Centre de Biologie Structurale), University of Montpellier, CNRS UMR 5048, INSERM U 1054, 29 Rue de Navacelles, 34090 Montpellier, France
| | - Chantal Cazevieille
- COMET Electron Microscopy Platform, INM (Institute for Neurosciences of Montpellier), University of Montpellier, INSERM U 1298, 80 Rue Augustin Fliche, 34091 Montpellier, France
| | - François Hoh
- CBS (Centre de Biologie Structurale), University of Montpellier, CNRS UMR 5048, INSERM U 1054, 29 Rue de Navacelles, 34090 Montpellier, France
| | - Sébastien Lyonnais
- CEMIPAI (Centre d'Etudes des Maladies Infectieuses et Pharmacologie Anti-Infectieuse), University of Montpellier, UAR 3725 CNRS, Montpellier, France
| | - Patrick Bron
- CBS (Centre de Biologie Structurale), University of Montpellier, CNRS UMR 5048, INSERM U 1054, 29 Rue de Navacelles, 34090 Montpellier, France
| | - Luca Cipelletti
- L2C (Laboratoire Charles Coulomb), University of Montpellier, CNRS, Place E. Bataillon, 34095 Montpellier, France; IUF (Institut Universitaire de France), Paris, France
| | - Laura Picas
- IRIM (Institut de Recherche en Infectiologie de Montpellier), University of Montpellier, CNRS UMR 9004, 1919 Route de Mende, 34293 Montpellier, France
| | - Simonetta Piatti
- CRBM (Centre de Recherche en Biologie cellulaire de Montpellier), University of Montpellier, CNRS UMR 5237, 1919 Route de Mende, 34293 Montpellier, France.
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42
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Grigaitis P, Teusink B. An excess of glycolytic enzymes under glucose-limited conditions may enable Saccharomyces cerevisiae to adapt to nutrient availability. FEBS Lett 2022; 596:3203-3210. [PMID: 36008883 DOI: 10.1002/1873-3468.14484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/11/2022] [Accepted: 08/18/2022] [Indexed: 01/14/2023]
Abstract
Microorganisms, including the budding yeast Saccharomyces cerevisiae, express glycolytic proteins to a maximal capacity that (largely) exceeds the actual flux through the enzymes, especially at low growth rates. An open question is if this apparent expression level is really an overcapacity, or maintains the (optimal) enzyme capacity needed to carry flux at (very) low substrate availability. Here, we use computational modelling to suggest that yeast maintains a genuine excess of glycolytic enzymes at low specific growth rates. During fast fermentative growth at high glucose levels, the observed expression of the glycolytic enzymes matched the predicted optimal levels. We suggest that the excess glycolytic capacity at low glucose levels is a preparatory strategy in the adaptation to sugar fluctuations in the environment.
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Affiliation(s)
- Pranas Grigaitis
- Systems Biology Lab, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, The Netherlands
| | - Bas Teusink
- Systems Biology Lab, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, The Netherlands
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43
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Abstract
The spindle position checkpoint (SPOC) is a mitotic surveillance mechanism in Saccharomyces cerevisiae that prevents cells from completing mitosis in response to spindle misalignment, thereby contributing to genomic integrity. The kinase Kin4, one of the most downstream SPOC components, is essential to stop the mitotic exit network (MEN), a signalling pathway that promotes the exit from mitosis and cell division. Previous work, however, suggested that a Kin4-independent pathway contributes to SPOC, yet the underlying mechanisms remain elusive. Here, we established the glycogen-synthase-kinase-3 (GSK-3) homologue Mck1, as a novel component that works independently of Kin4 to engage SPOC. Our data indicate that both Kin4 and Mck1 work in parallel to counteract MEN activation by the Cdc14 early anaphase release (FEAR) network. We show that Mck1's function in SPOC is mediated by the pre-replication complex protein and mitotic cyclin-dependent kinase (M-Cdk) inhibitor, Cdc6, which is degraded in a Mck1-dependent manner prior to mitosis. Moderate overproduction of Cdc6 phenocopies MCK1 deletion and causes SPOC deficiency via its N-terminal, M-Cdk inhibitory domain. Our data uncover an unprecedented role of GSK-3 kinases in coordinating spindle orientation with cell cycle progression.
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Affiliation(s)
- Siddhi Rathi
- Centre for Organismal Studies (COS), University of Heidelberg, Heidelberg, Germany,Heidelberg Biosciences International Graduate School (HBIGS) and Faculty of Biosciences, University of Heidelberg, Heidelberg, Germany,German Academic Exchange Service (DAAD), Bonn, Germany
| | - Irem Polat
- Centre for Organismal Studies (COS), University of Heidelberg, Heidelberg, Germany
| | - Gislene Pereira
- Centre for Organismal Studies (COS), University of Heidelberg, Heidelberg, Germany,Centre for Molecular Biology (ZMBH), University of Heidelberg, Heidelberg, Germany,German Cancer Research Centre (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany
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44
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Abstract
The spindle position checkpoint (SPOC) is a mitotic surveillance mechanism in Saccharomyces cerevisiae that prevents cells from completing mitosis in response to spindle misalignment, thereby contributing to genomic integrity. The kinase Kin4, one of the most downstream SPOC components, is essential to stop the mitotic exit network (MEN), a signalling pathway that promotes the exit from mitosis and cell division. Previous work, however, suggested that a Kin4-independent pathway contributes to SPOC, yet the underlying mechanisms remain elusive. Here, we established the glycogen-synthase-kinase-3 (GSK-3) homologue Mck1, as a novel component that works independently of Kin4 to engage SPOC. Our data indicate that both Kin4 and Mck1 work in parallel to counteract MEN activation by the Cdc14 early anaphase release (FEAR) network. We show that Mck1's function in SPOC is mediated by the pre-replication complex protein and mitotic cyclin-dependent kinase (M-Cdk) inhibitor, Cdc6, which is degraded in a Mck1-dependent manner prior to mitosis. Moderate overproduction of Cdc6 phenocopies MCK1 deletion and causes SPOC deficiency via its N-terminal, M-Cdk inhibitory domain. Our data uncover an unprecedented role of GSK-3 kinases in coordinating spindle orientation with cell cycle progression.
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Affiliation(s)
- Siddhi Rathi
- Centre for Organismal Studies (COS), University of Heidelberg, Heidelberg, Germany.,Heidelberg Biosciences International Graduate School (HBIGS) and Faculty of Biosciences, University of Heidelberg, Heidelberg, Germany.,German Academic Exchange Service (DAAD), Bonn, Germany
| | - Irem Polat
- Centre for Organismal Studies (COS), University of Heidelberg, Heidelberg, Germany
| | - Gislene Pereira
- Centre for Organismal Studies (COS), University of Heidelberg, Heidelberg, Germany.,Centre for Molecular Biology (ZMBH), University of Heidelberg, Heidelberg, Germany.,German Cancer Research Centre (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany
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45
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Aguilar RR, Shen ZJ, Tyler JK. A Simple, Improved Method for Scarless Genome Editing of Budding Yeast Using CRISPR-Cas9. Methods Protoc 2022; 5. [PMID: 36287051 DOI: 10.3390/mps5050079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 12/02/2022] Open
Abstract
Until recently, the favored method for making directed modifications to the budding yeast genome involved the introduction of a DNA template carrying the desired genetic changes along with a selectable marker, flanked by homology arms. This approach both limited the ability to make changes within genes due to disruption by the introduced selectable marker and prevented the use of that selectable marker for subsequent genomic manipulations. Following the discovery of CRISPR-Cas9-mediated genome editing, protocols were developed for modifying any DNA region of interest in a similar single transformation step without the need for a permanent selectable marker. This approach involves the generation of a DNA double-strand break (DSB) at the desired genomic location by the Cas9 nuclease, expressed on a plasmid which also expresses the guide RNA (gRNA) sequence directing the location of the DSB. The DSB is subsequently repaired via homologous recombination using a PCR-derived DNA repair template. Here, we describe in detail an improved method for incorporation of the gRNA-encoding DNA sequences into the Cas9 expression plasmid. Using Golden Gate cloning, annealed oligonucleotides bearing unique single-strand DNA overhangs are ligated into directional restriction enzyme sites. We describe the use of this CRISPR-Cas9 genome editing protocol to introduce multiple types of directed genetic changes into the yeast genome.
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46
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Meduri R, Rubio LS, Mohajan S, Gross DS. Phase-separation antagonists potently inhibit transcription and broadly increase nucleosome density. J Biol Chem 2022; 298:102365. [PMID: 35963432 PMCID: PMC9486037 DOI: 10.1016/j.jbc.2022.102365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 11/24/2022] Open
Abstract
Biomolecular condensates are self-organized membraneless bodies involved in many critical cellular activities, including ribosome biogenesis, protein synthesis, and gene transcription. Aliphatic alcohols are commonly used to study biomolecular condensates, but their effects on transcription are unclear. Here, we explore the impact of the aliphatic dialcohol, 1,6-hexanediol (1,6-HD), on Pol II transcription and nucleosome occupancy in budding yeast. As expected, 1,6-HD, a reagent effective in disrupting biomolecular condensates, strongly suppressed the thermal stress–induced transcription of Heat Shock Factor 1–regulated genes that have previously been shown to physically interact and coalesce into intranuclear condensates. Surprisingly, the isomeric dialcohol, 2,5-HD, typically used as a negative control, abrogated Heat Shock Factor 1–target gene transcription under the same conditions. Each reagent also abolished the transcription of genes that do not detectably coalesce, including Msn2/Msn4-regulated heat-inducible genes and constitutively expressed housekeeping genes. Thus, at elevated temperature (39 °C), HDs potently inhibit the transcription of disparate genes and as demonstrated by chromatin immunoprecipitation do so by abolishing occupancy of RNA polymerase in chromatin. Concurrently, histone H3 density increased at least twofold within all gene coding and regulatory regions examined, including quiescent euchromatic loci, silent heterochromatic loci, and Pol III-transcribed loci. Our results offer a caveat for the use of HDs in studying the role of condensates in transcriptional control and provide evidence that exposure to these reagents elicits a widespread increase in nucleosome density and a concomitant loss of both Pol II and Pol III transcription.
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Affiliation(s)
- Rajyalakshmi Meduri
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA
| | - Linda S Rubio
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA
| | - Suman Mohajan
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA
| | - David S Gross
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA.
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47
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Jiang S, Tang Y, Xiang L, Zhu X, Cai Z, Li L, Chen Y, Chen P, Feng Y, Lin X, Li G, Sharif J, Dai J. Efficient de novo assembly and modification of large DNA fragments. Sci China Life Sci 2022; 65:1445-1455. [PMID: 34939159 DOI: 10.1007/s11427-021-2029-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 11/11/2021] [Indexed: 06/14/2023]
Abstract
Synthetic genomics has provided new bottom-up platforms for the functional study of viral and microbial genomes. The construction of the large, gigabase (Gb)-sized genomes of higher organisms will deepen our understanding of genetic blueprints significantly. But for the synthesis and assembly of such large-scale genomes, the development of new or expanded methods is required. In this study, we develop an efficient pipeline for the construction of large DNA fragments sized 100 kilobases (kb) or above from scratches and describe an efficient method for "scar-free" engineering of the assembled sequences. Our method, therefore, should provide a standard framework for producing long DNA molecules, which are critical materials for synthetic genomics and metabolic engineering.
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Affiliation(s)
- Shuangying Jiang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yuanwei Tang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Liang Xiang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Xinlu Zhu
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Zelin Cai
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ling Li
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yingxi Chen
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Peishuang Chen
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yuge Feng
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xin Lin
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Guoqiang Li
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Jafar Sharif
- Developmental Genetics Laboratory, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, 230-0045, Japan
| | - Junbiao Dai
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
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48
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Kim J, Rose MD. Cla4p Kinase Activity Is Down-Regulated by Fus3p during Yeast Mating. Biomolecules 2022; 12:598. [PMID: 35454186 DOI: 10.3390/biom12040598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/12/2022] [Accepted: 04/14/2022] [Indexed: 01/20/2023] Open
Abstract
In Saccharomyces cerevisiae, the p21-activated kinase Cla4p regulates polarized morphogenesis and cytokinesis. However, it remains unknown how Cla4p kinase activity is regulated. After pheromone exposure, yeast cells temporally separate the mitotic and mating programs by sequestering Fus2p in the nucleus until cell cycle completion, after which Fus2p exits to facilitate cell fusion. Previously, we showed that sequestration is regulated by two opposing protein kinases, Cla4p and Fus3p. Phosphorylation of Fus2p-S67 by Cla4p promotes nuclear localization by both activating nuclear import and blocking export. During mating, phosphorylation of Fus2p-S85 and Fus2p-S100 by Fus3p promotes nuclear export and blocks import. Here, we find that Cla4p kinase activity is itself down-regulated during mating. Pheromone exposure causes Cla4p hyper-phosphorylation and reduced Fus2p-S67 phosphorylation, dependent on Fus3p. Multiple phosphorylation sites in Cla4p are mating- and/or Fus3p-specific. Of these, Cla4p-S186 phosphorylation reduced the kinase activity of Cla4p, in vitro. A phosphomimetic cla4-S186E mutation caused a strong reduction in Fus2p-S67 phosphorylation and nuclear localization, in vivo. More generally, a non-phosphorylatable mutation, cla4-S186A, caused failure to maintain pheromone arrest and delayed formation of the mating-specific septin morphology. Thus, as cells enter the mating pathway, Fus3p counteracts Cla4p kinase activity to allow proper mating differentiation.
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49
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Abstract
Genome instability causes cellular senescence in many organisms. The rRNA gene cluster (rDNA) is one of the most unstable regions in the genome and this instability might convey a signal that induces senescence in the budding yeast. The instability of rDNA mostly depends on replication fork blocking (RFB) activity which induces recombination and gene amplification. By overexpression of Fob1, responsible for the RFB activity, we found that unstable rDNA induces cell cycle arrest and restricts replicative life span. We isolated yeast mutants that grew normally while Fob1 was overexpressed, expecting that some of the mutated genes would be related to the production of a “senescence signal” that elongates cell cycle, stops cell division and finally restricts replicative life span. Our screen identified three suppressor genes, RPS12, UBC4, and CCR4. Replicative life spans of the rps12 and ubc4 mutants were longer than that of wild-type cells. An increase in the levels of extrachromosomal rDNA circles and noncoding transcripts, known to shorten replicative life span, was observed in ubc4 and rps12 respectively, while DNA double strand-breaks at the RFB that are triggers of rDNA instability were reduced in the rps12 mutant. Overall, our observations indicate that Rps12 and Ubc4 contribute to the connection between rDNA instability and replicative life span.
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50
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Komachi K, Burgess SM. The Nup2 meiotic-autonomous region relieves inhibition of Nup60 to promote progression of meiosis and sporulation in Saccharomyces cerevisiae. Genetics 2022; 221:6550504. [PMID: 35302609 PMCID: PMC9071577 DOI: 10.1093/genetics/iyac045] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 03/10/2022] [Indexed: 11/22/2022] Open
Abstract
During meiosis, chromosomes undergo dramatic changes in structural organization, nuclear positioning, and motion. Although the nuclear pore complex has been shown to affect genome organization and function in vegetative cells, its role in meiotic chromosome dynamics has remained largely unexplored. Recent work in the budding yeast Saccharomyces cerevisiae demonstrated that the mobile nucleoporin Nup2 is required for normal progression through meiosis I prophase and sporulation in strains where telomere-led chromosome movement has been compromised. The meiotic-autonomous region, a short fragment of Nup2 responsible for its role in meiosis, was shown to localize to the nuclear envelope via Nup60 and to bind to meiotic chromosomes. To understand the relative contribution these 2 activities have on meiotic-autonomous region function, we first carried out a screen for meiotic-autonomous region mutants defective in sporulation and found that all the mutations disrupt interaction with both Nup60 and meiotic chromosomes. Moreover, nup60 mutants phenocopy nup2 mutants, exhibiting similar nuclear division kinetics, sporulation efficiencies, and genetic interactions with mutations that affect the telomere bouquet. Although full-length Nup60 requires Nup2 for function, removal of Nup60's C-terminus allows Nup60 to bind meiotic chromosomes and promotes sporulation without Nup2. In contrast, binding of the meiotic-autonomous region to meiotic chromosomes is completely dependent on Nup60. Our findings uncover an inhibitory function for the Nup60 C-terminus and suggest that Nup60 mediates recruitment of meiotic chromosomes to the nuclear envelope, while Nup2 plays a secondary role counteracting the inhibitory function in Nup60's C-terminus.
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Affiliation(s)
- Kelly Komachi
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA
| | - Sean M Burgess
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA,Corresponding author: Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA.
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