DOCSLIB.ORG

COMMENTARY Cell Cycle Regulators in Drosophila: Downstream and Part of Developmental Decisions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
COMMENTARY Cell Cycle Regulators in Drosophila: Downstream and Part of Developmental Decisions Journal of Cell Science 110, 523-528 (1997) 523 Printed in Great Britain © The Company of Biologists Limited 1997 JCS4371 COMMENTARY Cell cycle regulators in Drosophila: downstream and part of developmental decisions Christian F. Lehner* and Mary Ellen Lane† Department of Genetics, University of Bayreuth, 95440 Bayreuth, Germany *Author for correspondence (e-mail: [email protected]) †Present address: Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge MA 02142, USA SUMMARY The molecular identification of an evolutionarily conserved how the mitotic cycle is transformed into an endocycle set of cell cycle regulators in yeast, Xenopus egg extracts, which allows the extensive growth of larvae and oocytes. In and vertebrate cell culture has opened up a new perspec- contrast, we know little about cyclin/cdk regulation during tive for understanding the mechanisms that regulate cell the imaginal proliferation that generates the cells of the proliferation during metazoan development. Now we can adult. Nevertheless, we will also consider this second devel- study how the crucial regulators of eukaryotic cell cycle opmental phase with its conspicuous regulative character, progression, the various cyclin/cdk complexes (for a recent because it will be of great interest for the analysis of the review see Nigg (1995) BioEssays 17, 471-480), are turned molecular mechanisms that integrate growth and prolifer- on or off during development. In Drosophila, this analysis ation during development. is most advanced, in particular in the case of the rather rigidly programmed embryonic cell cycles that generate the Key words: Cyclin, cdk, Cell cycle, Development, Oogenesis, cells of the larvae. In addition, this analysis has revealed Endoreduplication THE EMBRYONIC CELL DIVISION PROGRAM destabilize maternal mRNAs including twine and string mRNA which encode partially redundant cdc25 phosphatases (Edgar Cell proliferation during Drosophila embryogenesis follows a and Datar, 1996). These maternal cdc25 transcripts are no defined program reflecting the developmental regulation of longer detectable after mitosis 13 (M13). The Cdc25string cyclin/cdk complexes. At the beginning of embryogenesis, protein, which is degraded during each mitosis just like A- and cyclin E/cdk2 (cdc2c) and A- and B-type cyclins in complexes B-type cyclins, and presumably the Cdc25twine protein as well, with cdk1(cdc2) are highly active and drive progression are also largely absent after their degradation in M13. Hence, through S and M phase, respectively. These complexes as well the early divisions stop. An additional division, however, is as all other components required for the initial nuclear division observed when the nucleo-cytoplasmic ratio is decreased (as in cycles are derived from maternal stores deposited in the egg in haploid embryos) or when the early zygotic transcription is quantities sufficient for more than thirteen cycles. Early inhibited (after α-amanitin injection). In the latter case, zygotic products, however, bring about a rapid removal of the maternal string and twine transcripts have been shown to maternal cdc25 provisions and make all subsequent divisions perdure and to be required for the extra division (Edgar and dependent on zygotic cdc25 production (Edgar and Datar, Datar, 1996). 1996, and references therein), since cdc25 phosphatase is indis- In contrast to cdc25, cyclin E/cdk2 and all other components pensable for the activation of the mitosis-promoting cdk1 required for S phase are still present after M13. This division, complexes. Both the onset of the early zygotic transcription therefore, is followed by an immediate progression into S causing the removal of maternal cdc25, as well as the zygotic phase (S14), as are previous and subsequent divisions of re-expression of cdc25, are precisely regulated by develop- embryogenesis. However, as a consequence of the removal of mental cues. It is this cdc25 regulation which dictates the the maternal cdc25 provisions, cells enter for the first time into embryonic division program. an extended G2 phase after completion of S14 and await The onset of the early zygotic transcription which results in zygotic cdc25string expression, which triggers progression the removal of maternal cdc25 is controlled by the nucleo-cyto- through M14 (Edgar et al., 1994). The onset of string tran- plasmic ratio. Beginning with cycle 10, an unidentified scription is dictated by the genes that specify positional infor- component becomes limiting for the exponential production of mation and developmental fate (patterning genes). Thus, cells nuclei. Thus, the rapid early cycles slow down, allowing the progress through M14 in a very dynamic spatial and temporal onset of early zygotic transcription. The first zygotic products pattern, which reflects the specification of the various devel- 524 C. F. Lehner and M. E. Lane opmental fates. Precisely regulated pulses of string transcrip- regulation of cyclin E expression (Knoblich et al., 1994) and tion also dictate the program of the subsequent divisions. This in parallel the up-regulation of the dacapo gene, which encodes complex transcriptional control of string is mediated by a very a CIP/KIP-type cdk inhibitor that functions as a cyclin E/cdk2 large upstream regulatory region that can be separated into inhibitor in vitro and presumably in vivo as well (de Nooij et distinct enhancer elements that direct transcription in defined al., 1996; Lane et al., 1996; for a review on cdk inhibitors, see cell types during particular cycles (Edgar et al., 1994). While Harper and Elledge et al., 1996). the string pulses are not affected by mutations blocking the cell In dacapo mutants, epidermal cells fail to enter G1 after M16 cycle, an alteration of the string expression pattern and conse- and instead continue through an additional cell cycle. Never- quently of the division program is caused by mutations in pat- theless, after the extra division, cells do not proliferate further, terning genes (Edgar et al., 1994), indicating that they provide but rather enter G1. The extra proliferation in dacapo mutants the predominant regulatory inputs for the string control region. is limited to one extra cycle because cyclin E and presumably It is obvious that an accurate temporal regulation of divisions other cell cycle regulators as well are down-regulated as in in development is of crucial importance whenever cell fates are wild-type embryos. The down-regulation of cyclin E (and other assigned with single cell precision. During CNS neurogenesis regulators) and the up-regulation of dacapo also occur when in Drosophila for instance, each neuroblast is specified as the cell cycle progression is arrested prematurely (Knoblich et al., founder of a specific, largely invariant lineage. No cell 1994; M. E. Lane and C. F. Lehner, unpublished). The divisions occur during the period when these individual processes that stop the embryonic cell proliferation, therefore, founder cells are specified within the ectodermal epithelium of are triggered whether or not the correct cell number has been the neurogenic region. Uncontrolled cell divisions during this reached (see also Busturia and Lawrence, 1994). The great selection process would probably result in frequent duplica- similarity of the patterns of dacapo and string transcript accu- tions of some of the neuroblast lineages. High accuracy is also mulation that is observed in the epidermis just prior to M16 a pre-eminent feature of Drosophila eye development. The raises the possibility that both genes are controlled by the same perfectly regular pattern of ommatidia is established in the developmental cues at this time. Thereby, progression through morphogenetic furrow that sweeps across the eye disc epi- the final mitosis is enforced by string, while dacapo ensures thelium during the larval and pupal stages. Cell divisions are that this terminal division is no longer followed by an strictly prevented in the morphogenetic furrow by a process immediate entry into S phase. that includes regulated string expression (Thomas and Zipursky, 1994; Heberlein et al., 1995). Such high precision processes are likely one reason why the intricate control of OOGENESIS AND ENDOREDUPLICATION string expression and mitosis has evolved. To what extent com- parable control is operating in vertebrate embryos is still Most of the postmitotic cells in Drosophila resume cell cycle unclear. progression, although not through mitotic but endocycles. The While mitosis must be inhibited for the sake of precise cell genome amplification resulting from these repeated rounds of fate specification in some instances, it might be required in S phase without intervening divisions allows extensive cell others. Cell specification in the neuroblast lineages, where an growth. The most dramatic cell growth, however, is observed exceptional number of different fates are specified often in oocytes. These cells have to undergo meiotic reduction and relying on asymmetric segregation and temporal regulation of cannot amplify the genome. But oocyte growth is nourished by determinants (Knoblich et al., 1995; Spana et al., 1995; Kraut nurse cells, which undergo extensive endoreduplication and are et al., 1996), reveals some cases where cell cycle progression intimately connected with the oocyte, and by follicle cells, is clearly indispensable for correct cell fate assignment which endoreduplicate and amplify the chorion genes. Ovaries, (Weigmann and Lehner, 1995; Cui and Doe, 1995),
Load more

Recommended publications
  • Plasticity in Ploidy: a Generalized Response to Stress
    Review Plasticity in ploidy: a generalized response to stress Daniel R. Scholes and Ken N. Paige School of Integrative Biology, University of Illinois at Urbana-Champaign, 515 Morrill Hall, 505 South Goodwin Avenue, Urbana, IL 61801, USA Endoreduplication, the replication of the genome with- or greater) are a general feature of endosperm and sus- out mitosis, leads to an increase in the cellular ploidy of pensor cells of seed across endopolyploid taxa [9]. Very low an organism over its lifetime, a condition termed ‘endo- (or the complete lack of) endopolyploidy across taxa is polyploidy’. Endopolyploidy is thought to play signifi- observed in a few cell types, including phloem companion cant roles in physiology and development through cells and stomatal guard cells, both of which serve highly cellular, metabolic, and genetic effects. While the occur- specialized functions that would possibly be disrupted by rence of endopolyploidy has been observed widely increased ploidy [7,9]. Because endoreduplication is a across taxa, studies have only recently begun to charac- somatic process, the embryo and meristematic cells terize and manipulate endopolyploidy with a focus on its (e.g., procambium, root and shoot apical meristems) also ecological and evolutionary importance. No compilation lack endopolyploidy [6,7,9]. Finally, mixed ploidy among of these examples implicating endoreduplication as a adjacent cells of the same type also occurs (e.g., leaf generalized response to stress has thus far been made, epidermal pavement cells range from 2C to 64C) [7,9]. despite the growing evidence supporting this notion. Although generalized patterns of endopolyploidy may We review here the recent literature of stress-induced be observed within and among plants, recent evidence endopolyploidy and suggest that plants employ endor- suggests that many plants that endoreduplicate can plas- eduplication as an adaptive, plastic response to mitigate tically increase their endopolyploidy beyond their ‘normal’ the effects of stress.
    [Show full text]
  • Cell Cycle Arrest and DNA Endoreduplication Following P21waf1/Cip1 Expression
    Oncogene (1998) 17, 1691 ± 1703 1998 Stockton Press All rights reserved 0950 ± 9232/98 $12.00 http://www.stockton-press.co.uk/onc Cell cycle arrest and DNA endoreduplication following p21Waf1/Cip1 expression Stewart Bates, Kevin M Ryan, Andrew C Phillips and Karen H Vousden ABL Basic Research Program, NCI-FCRDC, Building 560, Room 22-96, West 7th Street, Frederick, Maryland 21702-1201, USA p21Waf1/Cip1 is a major transcriptional target of p53 and there are an increasing number of regulatory mechan- has been shown to be one of the principal mediators of isms that serve to inhibit cdk activity. Primary amongst the p53 induced G1 cell cycle arrest. We show that in these is the expression of cdk inhibitors (CDKIs) that addition to the G1 block, p21Waf1/Cip1 can also contribute can bind to and inhibit cyclin/cdk complexes (Sherr to a delay in G2 and expression of p21Waf1/Cip1 gives rise and Roberts, 1996). These fall into two classes, the to cell cycle pro®les essentially indistinguishable from INK family which bind to cdk4 and cdk6 and inhibit those obtained following p53 expression. Arrest of cells complex formation with D-cyclins, and the p21Waf1/Cip1 in G2 likely re¯ects an inability to induce cyclin B1/cdc2 family that bind to cyclin/cdk complexes and inhibit kinase activity in the presence of p21Waf1/Cip1, although the kinase activity. inecient association of p21Waf1/Cip1 and cyclin B1 The p21Waf1/Cip1 family of CDKIs include p21Waf1/Cip1, suggests that the mechanism of inhibition is indirect. p27 and p57 and are broad range inhibitors of cyclin/ Cells released from an S-phase block were not retarded cdk complexes (Gu et al., 1993; Harper et al., 1993; in their ability to progress through S-phase by the Xiong et al., 1993; Firpo et al., 1994; Polyak et al., presence of p21Waf1/Cip1, despite ecient inhibition of 1994; Toyoshima and Hunter, 1994; Lee et al., 1995; cyclin E, A and B1 dependent kinase activity, suggesting Matsuoka et al., 1995).
    [Show full text]
  • Cyclin-Dependent Kinase Inhibitors KRP1 and KRP2 Are Involved in Grain Filling and Seed Germination in Rice (Oryza Sativa L.)
    International Journal of Molecular Sciences Article Cyclin-Dependent Kinase Inhibitors KRP1 and KRP2 Are Involved in Grain Filling and Seed Germination in Rice (Oryza sativa L.) Abolore Adijat Ajadi 1,2, Xiaohong Tong 1, Huimei Wang 1, Juan Zhao 1, Liqun Tang 1, Zhiyong Li 1, Xixi Liu 1, Yazhou Shu 1, Shufan Li 1, Shuang Wang 1,3, Wanning Liu 1, Sani Muhammad Tajo 1, Jian Zhang 1,* and Yifeng Wang 1,* 1 State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou 311400, China; [email protected] (A.A.A.); [email protected] (X.T.); [email protected] (H.W.); [email protected] (J.Z.); [email protected] (L.T.); [email protected] (Z.L.); [email protected] (X.L.); [email protected] (Y.S.); [email protected] (S.L.); [email protected] (S.W.); [email protected] (W.L.); [email protected] (S.M.T.) 2 Biotechnology Unit, National Cereals Research Institute, Badeggi, Bida 912101, Nigeria 3 College of Life Science, Yangtze University, Jingzhou 434025, China * Correspondence: [email protected] (J.Z.); [email protected] (Y.W.); Tel./Fax: +86-571-6337-0277 (J.Z.); +86-571-6337-0206 (Y.W.) Received: 21 November 2019; Accepted: 26 December 2019; Published: 30 December 2019 Abstract: Cyclin-dependent kinase inhibitors known as KRPs (kip-related proteins) control the progression of plant cell cycles and modulate various plant developmental processes. However, the function of KRPs in rice remains largely unknown. In this study, two rice KRPs members, KRP1 and KRP2, were found to be predominantly expressed in developing seeds and were significantly induced by exogenous abscisic acid (ABA) and Brassinosteroid (BR) applications.
    [Show full text]
  • Involvement in Endoreduplication (Cell Cycle/Repa/Wheat Dwarf Virus) GIDEON GRAFI*T#, RONALD J
    Proc. Natl. Acad. Sci. USA Vol. 93, pp. 8962-8967, August 1996 Cell Biology A maize cDNA encoding a member of the retinoblastoma protein family: Involvement in endoreduplication (cell cycle/RepA/wheat dwarf virus) GIDEON GRAFI*t#, RONALD J. BURNETTr*, TIM HELENTJARIS*, BRIAN A. LARKINS*§, JAMES A. DECAPRIOt, WILLIAM R. SELLERSt, AND WILLIAM G. KAELIN, JR.t *Department of Plant Sciences, University of Arizona, Tucson AZ 85721; and tDana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02115 Contributed by Brian A. Larkins, May 14, 1996 ABSTRACT Retinoblastoma (RB-1) is a tumor suppres- We identified a partial maize cDNA (ZmRB) that is pre- sor gene that encodes a 105-kDa nuclear phosphoprotein. To dicted to encode a protein with homology to members of the date, RB genes have been isolated only from metazoans. We pocket protein (Rb) family. Here we provide evidence that have isolated a cDNA from maize endosperm whose predicted ZmRb is a member of the retinoblastoma protein family and protein product (ZmRb) shows homology to the "pocket" A demonstrate its ability to bind the replication-associated pro- and B domains of the Rb protein family. We found ZmRb tein WDV RepA and its involvement in the process of DNA behaves as a pocket protein based on its ability to specifically endoreduplication during maize endosperm development. interact with oncoproteins encoded by DNA tumor viruses (E7, T-Ag, E1A). ZmRb can interact in vitro and in vivo with MATERIALS AND METHODS the replication-associated protein, RepA, encoded by the wheat dwarf virus. The maize Rb-related protein undergoes Plant Materials and Chemicals.
    [Show full text]
  • Perspectives
    CopyTight 0 1997 by the Genetics Society of America Perspectives Anecdotal, Historical And Critical Commentaries on Genetics Edited by James F. Crow and William F. Dove Chromosome Changes in Cell Differentiation Orlando J. Miller Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan 48201 N a recent “Perspectives” article, EEVA THEW the H19 gene. The maternal H19 allele is expressed, I (1995) called attention to a variety of alterations and its cis-acting, nontranslatable RNA product inhibits in chromosomes that occur regularly in differentiating the expression of the maternal alleles of the other three cells, have been known for many years, and are still genes, mash-2, Ins-2, and I@. The paternal H19 allele poorly understood. Theseincludedfacultatiue heterochro- is methylated and notexpressed, so the paternal alleles matinization, polyploidization by endoreduplication, under- of the other three genes are expressed. Imprinting of replication ofsome sequences inpolytene chromosomes, the Inns-2 and I@ genes is disrupted by maternal inheri- and gene amplijication. The related programmed DNA tance of a targeted deletion of the H19 gene and its loss phenomena called chromatin diminutionand chromo- flanking sequence, while paternal inheritance has no some eliminationalso belong tothis group of highly regu- effect, reflecting the normally silent state of the pater- lated developmental chromosomechanges. Here Ishall nal HI 9 allele (LEIGHTONet al. 1995). There is also a briefly review these changes, with particular emphasis cluster of several genes on human chromosome 15 that on thecell and molecular genetic approaches thathave are expressed exclusively on thepaternal chromosome; provided, or could provide, insights into the signaling these may play a role in thePrader-Willi syndrome.
    [Show full text]
  • Endoreduplication in Drosophila Melanogaster Progeny After Exposure to Acute Γ-Irradiation
    bioRxiv preprint doi: https://doi.org/10.1101/376145; this version posted July 24, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Endoreduplication in Drosophila melanogaster progeny after exposure to acute γ-irradiation Running head: Endoreduplication in Drosophila after γ- Keywords: giant chromosomes, polyteny degree, developmental rate, embryonic mortality, ionizing radiation. Daria A. Skorobagatko VN Karazin Kharkiv National University, Department of Genetics and Cytology, Svobody sq., 4, Kharkiv, 61022, Ukraine E-mail: [email protected] Phone: +380673007826 Alexey A. Mazilov Ph D NSC ‘Kharkiv Institute of Physics and Technology’, Department of Physics of Radiation and Multichannel Track Detectors, Academic str., 1, Kharkiv, 61108, Ukraine E-mail: [email protected] Phone: +380679950495 Volodymyr Yu. Strashnyuk Dr Sci (corresponding author) VN Karazin Kharkiv National University, Department of Genetics and Cytology, Svobody sq., 4, Kharkiv, 61022, Ukraine E-mail: [email protected] Phone: +380679478350 bioRxiv preprint doi: https://doi.org/10.1101/376145; this version posted July 24, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 2 Abstract The purpose of investigation was to study the effect of acute γ-irradiation of parent adults on the endoreduplication in Drosophila melanogaster progeny. As a material used Oregon-R strain. Virgin females and males of Drosophila adults at the age of 3 days were exposed at the doses of 8, 16 and 25 Gy. Giant chromosomes were studied at late 3rd instar larvae by cytomorphometric method.
    [Show full text]
  • Endoreduplication in Floral Structure, Vegetative and Fruits of Red Pitaya with White Pulp
    931 Original Article ENDOREDUPLICATION IN FLORAL STRUCTURE, VEGETATIVE AND FRUITS OF RED PITAYA WITH WHITE PULP ENDORREDUPLICAÇÃO EM ESTRUTURA FLORAL, VEGETATIVA E FRUTOS DE PITAYA VERMELHA DE POLPA BRANCA Thatiane Padilha de MENEZES 1; Leila Aparecida Salles PIO 2; José Darlan RAMOS 3; Moacir PASQUAL 4; Tesfahum Alemu SETOTAW5 1. Doutora em Agronomia, Universidade Federal de Lavras – UFLA, Lavras, MG, Brasil. [email protected]; 2. Professora, Doutora em Agronomia, Universidade Federal de Lavras – UFLA, Lavras, MG, Brasil; 3. Professor, Doutor em Agronomia, Universidade Federal de Lavras – UFLA, Lavras, MG, Brasil; 4. Professor, Doutor em Agronomia, Universidade Federal de Lavras – UFLA, Lavras, MG, Brasil. [email protected]; 5. Doutor em Agonomia, Universidade Federal de Lavras – UFLA, Lavras, MG, Brasil. ABSTRACT: Endoreduplication is the change of cellular cycle that result DNA duplication without cell division and could result endopolyploid cells. This phenomenon is common in plants and animals and considered as evaluative strategy. Although endoreduplication reported in various plant species, the information about these phenomena in red pitaya is rare. Therefore, this work was done with the objective of studying the endoreduplication in Hylocereus undatus Haw. using flow cytometry analysis. In this study were used the tissue from the flower structure, fruits, roots, cladode, and thorns of the pitaya plant.To determine the DNA content approximately 50 mg the sample of each treatment with Pisum sativum (the internal standard reference) were grind in plate of petri dishes contained 1 mL of cold Marie buffer to release the nucleus.The nuclear suspension was filtered through 50 µm mesh. The nucleuses were colored with 25 µL of 1 mg/L mL of propidium iodide.
    [Show full text]
  • SAMBA, a Plant-Specific Anaphase-Promoting Complex/Cyclosome Regulator Is Involved in Early Development and A-Type Cyclin Stabilization Nubia B
    SAMBA, a plant-specific anaphase-promoting complex/cyclosome regulator is involved in early development and A-type cyclin stabilization Nubia B. Eloy, Nathalie Gonzalez, Jelle van Leene, Katrien Maleux, Hannes Vanhaeren, Liesbeth de Milde, Stijn Dhondt, Leen Vercruysse, Erwin Witters, Raphaël Mercier, et al. To cite this version: Nubia B. Eloy, Nathalie Gonzalez, Jelle van Leene, Katrien Maleux, Hannes Vanhaeren, et al.. SAMBA, a plant-specific anaphase-promoting complex/cyclosome regulator is involved in early de- velopment and A-type cyclin stabilization. Proceedings of the National Academy of Sciences of the United States of America , National Academy of Sciences, 2012, 109 (34), pp.13853 - 13858. 10.1073/pnas.1211418109. hal-01190736 HAL Id: hal-01190736 https://hal.archives-ouvertes.fr/hal-01190736 Submitted on 29 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. SAMBA, a plant-specific anaphase-promoting complex/ cyclosome regulator is involved in early development and A-type cyclin stabilization Nubia B. Eloya,b, Nathalie Gonzaleza,b, Jelle Van Leenea,b, Katrien Maleuxa,b, Hannes Vanhaerena,b, Liesbeth De Mildea,b, Stijn Dhondta,b, Leen Vercruyssea,b, Erwin Wittersc,d,e, Raphaël Mercierf, Laurence Cromerf, Gerrit T.
    [Show full text]
  • Chromosome–Nuclear Envelope Tethering – a Process That Orchestrates Homologue Pairing During Plant Meiosis? Adél Sepsi1,2,* and Trude Schwarzacher3,4
    © 2020. Published by The Company of Biologists Ltd | Journal of Cell Science (2020) 133, jcs243667. doi:10.1242/jcs.243667 REVIEW Chromosome–nuclear envelope tethering – a process that orchestrates homologue pairing during plant meiosis? Adél Sepsi1,2,* and Trude Schwarzacher3,4 ABSTRACT genome integrity from one generation to another relies on accurate During prophase I of meiosis, homologous chromosomes pair, homologous partner identification. synapse and exchange their genetic material through reciprocal In higher plants, hundreds of genome-wide double-strand breaks homologous recombination, a phenomenon essential for faithful (DSBs) (see Glossary) initiate meiotic recombination within a single chromosome segregation. Partial sequence identity between non- nucleus (Choi et al., 2013; Kurzbauer et al., 2012; Pawlowski et al., homologous and heterologous chromosomes can also lead to 2003). Interactions between homologous chromosomes follow recombination (ectopic recombination), a highly deleterious process recombination initiation (Bozza and Pawlowski, 2008; Hunter and that rapidly compromises genome integrity. To avoid ectopic Kleckner, 2001; Schwarzacher, 1997), suggesting an extremely quick exchange, homology recognition must be extended from the narrow and efficient activation of the homology recognition process. Moreover, – position of a crossover-competent double-strand break to the entire in allopolyploid species (see Glossary) such as the hexaploid wheat chromosome. Here, we review advances on chromosome behaviour Triticum aestivum (2n=6x=42, in which x indicates the number of – during meiotic prophase I in higher plants, by integrating centromere- haploid genomes) each homologous chromosome pair has not only and telomere dynamics driven by cytoskeletal motor proteins, into the one but often several highly similar, i.e. homoeologous (see Glossary), processes of homologue pairing, synapsis and recombination.
    [Show full text]
  • Programmed Induction of Endoreduplication by DNA Double-Strand Breaks in Arabidopsis
    Programmed induction of endoreduplication by DNA double-strand breaks in Arabidopsis Sumiko Adachia, Kazunori Minamisawaa, Yoko Okushimaa, Soichi Inagakia, Kaoru Yoshiyamaa, Youichi Kondoub, Eli Kaminumac, Mika Kawashimab, Tetsuro Toyodac, Minami Matsuib, Daisuke Kuriharad,e, Sachihiro Matsunagaf,g, and Masaaki Umedaa,1 aGraduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan; bPlant Science Center and cBioinformatics and Systems Engineering Division, Institute of Physical and Chemical Research (RIKEN), 1-7-22 Suehirocho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; dDivision of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; eHigashiyama Live-Holonics Project, Japan Science and Technology Exploratory Research for Advanced Technology, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan; fDepartment of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; and gDepartment of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan Edited* by Brian A. Larkins, University of Arizona, Tuscon, AZ, and approved May 4, 2011 (received for review March 8, 2011) Genome integrity is continuously threatened by external stresses orthologs, and knockout mutants show similar phenotypes to and endogenous hazards such as DNA replication errors and those of their mammalian counterparts. Arabidopsis atm mutants reactive oxygen species. The DNA damage checkpoint in meta- are sensitive to gamma radiation and are defective in transcrip- zoans ensures genome integrity by delaying cell-cycle progression tional induction of repair genes in response to irradiation (8). atr to repair damaged DNA or by inducing apoptosis.
    [Show full text]
  • SOG1 Transcription Factor Promotes the Onset of Endoreduplication Under Salinity Stress in Arabidopsis Kalyan Mahapatra & Sujit Roy*
    www.nature.com/scientificreports OPEN SOG1 transcription factor promotes the onset of endoreduplication under salinity stress in Arabidopsis Kalyan Mahapatra & Sujit Roy* As like in mammalian system, the DNA damage responsive cell cycle checkpoint functions play crucial role for maintenance of genome stability in plants through repairing of damages in DNA and induction of programmed cell death or endoreduplication by extensive regulation of progression of cell cycle. ATM and ATR (ATAXIA-TELANGIECTASIA-MUTATED and -RAD3-RELATED) function as sensor kinases and play key role in the transmission of DNA damage signals to the downstream components of cell cycle regulatory network. The plant-specifc NAC domain family transcription factor SOG1 (SUPPRESSOR OF GAMMA RESPONSE 1) plays crucial role in transducing signals from both ATM and ATR in presence of double strand breaks (DSBs) in the genome and found to play crucial role in the regulation of key genes involved in cell cycle progression, DNA damage repair, endoreduplication and programmed cell death. Here we report that Arabidopsis exposed to high salinity shows generation of oxidative stress induced DSBs along with the concomitant induction of endoreduplication, displaying increased cell size and DNA ploidy level without any change in chromosome number. These responses were signifcantly prominent in SOG1 overexpression line than wild-type Arabidopsis, while sog1 mutant lines showed much compromised induction of endoreduplication under salinity stress. We have found that both ATM-SOG1 and ATR-SOG1 pathways are involved in the salinity mediated induction of endoreduplication. SOG1was found to promote G2-M phase arrest in Arabidopsis under salinity stress by downregulating the expression of the key cell cycle regulators, including CDKB1;1, CDKB2;1, and CYCB1;1, while upregulating the expression of WEE1 kinase, CCS52A and E2Fa, which act as important regulators for induction of endoreduplication.
    [Show full text]
  • The Plant DNA Damage Response: Signaling Pathways Leading To
    The Plant DNA Damage Response: Signaling Pathways Leading to Growth Inhibition and Putative Role in Response to Stress Conditions Maher-Un Nisa, Ying Huang, Moussa Benhamed, Cécile Raynaud To cite this version: Maher-Un Nisa, Ying Huang, Moussa Benhamed, Cécile Raynaud. The Plant DNA Damage Response: Signaling Pathways Leading to Growth Inhibition and Putative Role in Response to Stress Conditions. Frontiers in Plant Science, Frontiers, 2019, 10, 10.3389/fpls.2019.00653. hal-02351967 HAL Id: hal-02351967 https://hal.archives-ouvertes.fr/hal-02351967 Submitted on 26 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License fpls-10-00653 May 17, 2019 Time: 15:12 # 1 REVIEW published: 17 May 2019 doi: 10.3389/fpls.2019.00653 The Plant DNA Damage Response: Signaling Pathways Leading to Growth Inhibition and Putative Role in Response to Stress Conditions Maher-Un Nisa, Ying Huang, Moussa Benhamed and Cécile Raynaud* Institute of Plant Sciences Paris-Saclay, IPS2, CNRS-INRA-University of Paris Sud, Paris-Diderot and Evry, University of Paris-Saclay, Gif-sur-Yvette, France Maintenance of genome integrity is a key issue for all living organisms.
    [Show full text]