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Ponomartsev SV, Sinenko SA, Tomilin AN. Human Artificial Chromosomes and Their Transfer to Target Cells. Acta Naturae 2022; 14:35-45. [PMID: 36348716 PMCID: PMC9611860 DOI: 10.32607/actanaturae.11670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 07/12/2022] [Indexed: 11/02/2023] Open
Abstract
Human artificial chromosomes (HACs) have been developed as genetic vectors with the capacity to carry large transgenic constructs or entire gene loci. HACs represent either truncated native chromosomes or de novo synthesized genetic constructs. The important features of HACs are their ultra-high capacity and ability to self-maintain as independent genetic elements, without integrating into host chromosomes. In this review, we discuss the development and construction methods, structural and functional features, as well as the areas of application of the main HAC types. Also, we address one of the most technically challenging and time-consuming steps in this technology - the transfer of HACs from donor to recipient cells.
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Affiliation(s)
- S. V. Ponomartsev
- Institute of Cytology Russian Academy of Sciences, St. Petersburg, 194064 Russia
| | - S. A. Sinenko
- Institute of Cytology Russian Academy of Sciences, St. Petersburg, 194064 Russia
| | - A. N. Tomilin
- Institute of Cytology Russian Academy of Sciences, St. Petersburg, 194064 Russia
- Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, 199034 Russia
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2
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Chen Y, Zhang Q, Teng Z, Liu H. Centromeric transcription maintains centromeric cohesion in human cells. J Cell Biol 2021; 220:e202008146. [PMID: 33881484 PMCID: PMC8065269 DOI: 10.1083/jcb.202008146] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 02/19/2021] [Accepted: 03/24/2021] [Indexed: 02/07/2023] Open
Abstract
Centromeric transcription has been shown to play an important role in centromere functions. However, lack of approaches to specifically manipulate centromeric transcription calls into question that the proposed functions are a direct consequence of centromeric transcription. By monitoring nascent RNAs, we found that several transcriptional inhibitors exhibited distinct, even opposing, efficacies on the suppression of ongoing gene and centromeric transcription in human cells, whereas under the same conditions, total centromeric RNAs were changed to a lesser extent. The inhibitor suppressing ongoing centromeric transcription weakened centromeric cohesion, whereas the inhibitor increasing ongoing centromeric transcription strengthened centromeric cohesion. Furthermore, expression of CENP-B DNA-binding domain or CENP-B knockdown moderately increased centromeric transcription without altering gene transcription; as a result, centromeric cohesion was accordingly strengthened. Targeting of the Kox1-KRAB domain with CENP-B DB to centromeres specifically decreased centromeric transcription and weakened centromeric cohesion. Thus, based on these findings, we propose that a major function of centromeric transcription is to maintain centromeric cohesion in human cells.
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Affiliation(s)
- Yujue Chen
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA
| | - Qian Zhang
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA
| | - Zhen Teng
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA
| | - Hong Liu
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA
- Tulane Aging Center, Tulane University School of Medicine, New Orleans, LA
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3
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Boštjančić LL, Bonassin L, Anušić L, Lovrenčić L, Besendorfer V, Maguire I, Grandjean F, Austin CM, Greve C, Hamadou AB, Mlinarec J. The Pontastacus leptodactylus (Astacidae) Repeatome Provides Insight Into Genome Evolution and Reveals Remarkable Diversity of Satellite DNA. Front Genet 2021; 11:611745. [PMID: 33552130 PMCID: PMC7859515 DOI: 10.3389/fgene.2020.611745] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/21/2020] [Indexed: 12/14/2022] Open
Abstract
Pontastacus leptodactylus is a native European crayfish species found in both freshwater and brackish environments. It has commercial importance for fisheries and aquaculture industries. Up till now, most studies concerning P. leptodactylus have focused onto gaining knowledge about its phylogeny and population genetics. However, little is known about the chromosomal evolution and genome organization of this species. Therefore, we performed clustering analysis of a low coverage genomic dataset to identify and characterize repetitive DNA in the P. leptodactylus genome. In addition, the karyogram of P. leptodactylus (2n = 180) is presented here for the first time consisting of 75 metacentric, 14 submetacentric, and a submetacentric/metacentric heteromorphic chromosome pair. We determined the genome size to be at ~18.7 gigabase pairs. Repetitive DNA represents about 54.85% of the genome. Satellite DNA repeats are the most abundant type of repetitive DNA, making up to ~28% of the total amount of repetitive elements, followed by the Ty3/Gypsy retroelements (~15%). Our study established a surprisingly high diversity of satellite repeats in P. leptodactylus. The genome of P. leptodactylus is by far the most satellite-rich genome discovered to date with 258 satellite families described. Of the five mapped satellite DNA families on chromosomes, PlSAT3-411 co-localizes with the AT-rich DAPI positive probable (peri)centromeric heterochromatin on all chromosomes, while PlSAT14-79 co-localizes with the AT-rich DAPI positive (peri)centromeric heterochromatin on one chromosome and is also located subterminally and intercalary on some chromosomes. PlSAT1-21 is located intercalary in the vicinity of the (peri)centromeric heterochromatin on some chromosomes, while PlSAT6-70 and PlSAT7-134 are located intercalary on some P. leptodactylus chromosomes. The FISH results reveal amplification of interstitial telomeric repeats (ITRs) in P. leptodactylus. The prevalence of repetitive elements, especially the satellite DNA repeats, may have provided a driving force for the evolution of the P. leptodactylus genome.
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Affiliation(s)
| | - Lena Bonassin
- Division of Molecular Biology, Department of Biology, University of Zagreb, Zagreb, Croatia
| | - Lucija Anušić
- Division of Molecular Biology, Department of Biology, University of Zagreb, Zagreb, Croatia
| | - Leona Lovrenčić
- Division of Zoology, Department of Biology, University of Zagreb, Zagreb, Croatia
| | - Višnja Besendorfer
- Division of Molecular Biology, Department of Biology, University of Zagreb, Zagreb, Croatia
| | - Ivana Maguire
- Division of Zoology, Department of Biology, University of Zagreb, Zagreb, Croatia
| | - Frederic Grandjean
- Laboratoire Ecologie Biologie des Interactions-UMR CNRS 7267, University of Poitiers, Poitiers, France
| | - Christopher M. Austin
- Centre of Integrative Ecology, School of Life and Environmental Sciences Deakin University, Geelong, VIC, Australia
| | - Carola Greve
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt, Germany
| | - Alexander Ben Hamadou
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt, Germany
| | - Jelena Mlinarec
- Division of Molecular Biology, Department of Biology, University of Zagreb, Zagreb, Croatia
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Wong CYY, Ling YH, Mak JKH, Zhu J, Yuen KWY. "Lessons from the extremes: Epigenetic and genetic regulation in point monocentromere and holocentromere establishment on artificial chromosomes". Exp Cell Res 2020; 390:111974. [PMID: 32222413 DOI: 10.1016/j.yexcr.2020.111974] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 02/08/2023]
Abstract
The formation of de novo centromeres on artificial chromosomes in humans (HACs) and fission yeast (SpYACs) has provided much insights to the epigenetic and genetic control on regional centromere establishment and maintenance. Similarly, the use of artificial chromosomes in point centromeric budding yeast Saccharomyces cerevisiae (ScYACs) and holocentric Caenorhabditis elegans (WACs) has revealed epigenetic regulation in the originally thought purely genetically-determined point centromeres and some centromeric DNA sequence features in holocentromeres, respectively. These relatively extreme and less characterized centromere organizations, on the endogenous chromosomes and artificial chromosomes, will be discussed and compared to the more well-studied regional centromere systems. This review will highlight some of the common epigenetic and genetic features in different centromere architectures, including the presence of the centromeric histone H3 variant, CENP-A or CenH3, centromeric and pericentric transcription, AT-richness and repetitiveness of centromeric DNA sequences.
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Affiliation(s)
- Charmaine Yan Yu Wong
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Yick Hin Ling
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Jason Ka Ho Mak
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Jing Zhu
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Karen Wing Yee Yuen
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong.
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5
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Tørresen OK, Star B, Mier P, Andrade-Navarro MA, Bateman A, Jarnot P, Gruca A, Grynberg M, Kajava AV, Promponas VJ, Anisimova M, Jakobsen KS, Linke D. Tandem repeats lead to sequence assembly errors and impose multi-level challenges for genome and protein databases. Nucleic Acids Res 2019; 47:10994-11006. [PMID: 31584084 PMCID: PMC6868369 DOI: 10.1093/nar/gkz841] [Citation(s) in RCA: 159] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/03/2019] [Accepted: 10/01/2019] [Indexed: 12/13/2022] Open
Abstract
The widespread occurrence of repetitive stretches of DNA in genomes of organisms across the tree of life imposes fundamental challenges for sequencing, genome assembly, and automated annotation of genes and proteins. This multi-level problem can lead to errors in genome and protein databases that are often not recognized or acknowledged. As a consequence, end users working with sequences with repetitive regions are faced with 'ready-to-use' deposited data whose trustworthiness is difficult to determine, let alone to quantify. Here, we provide a review of the problems associated with tandem repeat sequences that originate from different stages during the sequencing-assembly-annotation-deposition workflow, and that may proliferate in public database repositories affecting all downstream analyses. As a case study, we provide examples of the Atlantic cod genome, whose sequencing and assembly were hindered by a particularly high prevalence of tandem repeats. We complement this case study with examples from other species, where mis-annotations and sequencing errors have propagated into protein databases. With this review, we aim to raise the awareness level within the community of database users, and alert scientists working in the underlying workflow of database creation that the data they omit or improperly assemble may well contain important biological information valuable to others.
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Affiliation(s)
- Ole K Tørresen
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, NO-0316 Oslo, Norway
| | - Bastiaan Star
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, NO-0316 Oslo, Norway
| | - Pablo Mier
- Faculty of Biology, Johannes Gutenberg University Mainz, Hans-Dieter-Husch-Weg 15, 55128 Mainz, Germany
| | - Miguel A Andrade-Navarro
- Faculty of Biology, Johannes Gutenberg University Mainz, Hans-Dieter-Husch-Weg 15, 55128 Mainz, Germany
| | - Alex Bateman
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton. CB10 1SD, UK
| | - Patryk Jarnot
- Institute of Informatics, Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland
| | - Aleksandra Gruca
- Institute of Informatics, Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland
| | - Marcin Grynberg
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Andrey V Kajava
- Centre de Recherche en Biologie cellulaire de Montpellier, UMR 5237 CNRS, Universite Montpellier 1919 Route de Mende, CEDEX 5, 34293 Montpellier, France
- Institut de Biologie Computationnelle, 34095 Montpellier, France
| | - Vasilis J Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, PO Box 20537, CY 1678 Nicosia, Cyprus
| | - Maria Anisimova
- Institute of Applied Simulations, School of Life Sciences and Facility Management, Zurich University of Applied Sciences (ZHAW), Wädenswil, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Kjetill S Jakobsen
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, NO-0316 Oslo, Norway
| | - Dirk Linke
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, NO-0316 Oslo, Norway
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Yuan Z, Zhou T, Bao L, Liu S, Shi H, Yang Y, Gao D, Dunham R, Waldbieser G, Liu Z. The annotation of repetitive elements in the genome of channel catfish (Ictalurus punctatus). PLoS One 2018; 13:e0197371. [PMID: 29763462 PMCID: PMC5953449 DOI: 10.1371/journal.pone.0197371] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Accepted: 05/01/2018] [Indexed: 11/18/2022] Open
Abstract
Channel catfish (Ictalurus punctatus) is a highly adaptive species and has been used as a research model for comparative immunology, physiology, and toxicology among ectothermic vertebrates. It is also economically important for aquaculture. As such, its reference genome was generated and annotated with protein coding genes. However, the repetitive elements in the catfish genome are less well understood. In this study, over 417.8 Megabase (MB) of repetitive elements were identified and characterized in the channel catfish genome. Among them, the DNA/TcMar-Tc1 transposons are the most abundant type, making up ~20% of the total repetitive elements, followed by the microsatellites (14%). The prevalence of repetitive elements, especially the mobile elements, may have provided a driving force for the evolution of the catfish genome. A number of catfish-specific repetitive elements were identified including the previously reported Xba elements whose divergence rate was relatively low, slower than that in untranslated regions of genes but faster than the protein coding sequences, suggesting its evolutionary restrictions.
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Affiliation(s)
- Zihao Yuan
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Tao Zhou
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Lisui Bao
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Shikai Liu
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Huitong Shi
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Yujia Yang
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Dongya Gao
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Rex Dunham
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Geoff Waldbieser
- USDA-ARS Warmwater Aquaculture Research Unit, Stoneville, Mississippi, United States of America
| | - Zhanjiang Liu
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
- * E-mail:
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7
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Zhu Y, Engström PG, Tellgren-Roth C, Baudo CD, Kennell JC, Sun S, Billmyre RB, Schröder MS, Andersson A, Holm T, Sigurgeirsson B, Wu G, Sankaranarayanan SR, Siddharthan R, Sanyal K, Lundeberg J, Nystedt B, Boekhout T, Dawson TL, Heitman J, Scheynius A, Lehtiö J. Proteogenomics produces comprehensive and highly accurate protein-coding gene annotation in a complete genome assembly of Malassezia sympodialis. Nucleic Acids Res 2017; 45:2629-2643. [PMID: 28100699 PMCID: PMC5389616 DOI: 10.1093/nar/gkx006] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 01/16/2017] [Indexed: 11/23/2022] Open
Abstract
Complete and accurate genome assembly and annotation is a crucial foundation for comparative and functional genomics. Despite this, few complete eukaryotic genomes are available, and genome annotation remains a major challenge. Here, we present a complete genome assembly of the skin commensal yeast Malassezia sympodialis and demonstrate how proteogenomics can substantially improve gene annotation. Through long-read DNA sequencing, we obtained a gap-free genome assembly for M. sympodialis (ATCC 42132), comprising eight nuclear and one mitochondrial chromosome. We also sequenced and assembled four M. sympodialis clinical isolates, and showed their value for understanding Malassezia reproduction by confirming four alternative allele combinations at the two mating-type loci. Importantly, we demonstrated how proteomics data could be readily integrated with transcriptomics data in standard annotation tools. This increased the number of annotated protein-coding genes by 14% (from 3612 to 4113), compared to using transcriptomics evidence alone. Manual curation further increased the number of protein-coding genes by 9% (to 4493). All of these genes have RNA-seq evidence and 87% were confirmed by proteomics. The M. sympodialis genome assembly and annotation presented here is at a quality yet achieved only for a few eukaryotic organisms, and constitutes an important reference for future host-microbe interaction studies.
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Affiliation(s)
- Yafeng Zhu
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, 17121 Solna, Sweden
| | - Pär G Engström
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17121 Solna, Sweden
| | - Christian Tellgren-Roth
- National Genomics Infrastructure, Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, 75108 Uppsala, Sweden
| | - Charles D Baudo
- Department of Biology, Saint Louis University, St. Louis, MO 63103, USA
| | - John C Kennell
- Department of Biology, Saint Louis University, St. Louis, MO 63103, USA
| | - Sheng Sun
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - R Blake Billmyre
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Markus S Schröder
- School of Biomedical and Biomolecular Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Anna Andersson
- Department of Medicine Solna, Translational Immunology Unit, Karolinska Institutet and University Hospital, 17177 Stockholm, Sweden
| | - Tina Holm
- Department of Medicine Solna, Translational Immunology Unit, Karolinska Institutet and University Hospital, 17177 Stockholm, Sweden
| | - Benjamin Sigurgeirsson
- Science for Life Laboratory, School of Biotechnology, Royal Institute of Technology, 17121 Solna, Sweden
| | - Guangxi Wu
- Computational and Systems Biology, Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), 138672, Singapore
| | - Sundar Ram Sankaranarayanan
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, India
| | - Rahul Siddharthan
- The Institute of Mathematical Sciences/HBNI, Taramani, Chennai 600 113, India
| | - Kaustuv Sanyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064, India
| | - Joakim Lundeberg
- Science for Life Laboratory, School of Biotechnology, Royal Institute of Technology, 17121 Solna, Sweden
| | - Björn Nystedt
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, 75123 Uppsala, Sweden
| | - Teun Boekhout
- CBS-Fungal Biodiversity Centre, Utrecht, 3508, The Netherlands and Institute for Biodiversity and ecosystem Dynamics (IBED), University of Amsterdam, 1012 WX Amsterdam, The Netherlands
| | - Thomas L Dawson
- Institute of Medical Biology, Agency for Science, Technology and Research (A*STAR), 138648, Singapore
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Annika Scheynius
- Science for Life Laboratory, Department of Clinical Science and Education, Karolinska Institutet, and Sachs' Children and Youth Hospital, Södersjukhuset, SE-118 83 Stockholm, Sweden
| | - Janne Lehtiö
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, 17121 Solna, Sweden
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Rizvi SMA, Prajapati HK, Ghosh SK. The 2 micron plasmid: a selfish genetic element with an optimized survival strategy within Saccharomyces cerevisiae. Curr Genet 2017; 64:25-42. [PMID: 28597305 DOI: 10.1007/s00294-017-0719-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 05/29/2017] [Accepted: 05/30/2017] [Indexed: 11/27/2022]
Abstract
Since its discovery in the early 70s, the 2 micron plasmid of Saccharomyces cerevisiae continues to intrigue researchers with its high protein-coding capacity and a selfish nature yet high stability, earning it the title of a 'miniaturized selfish genetic element'. It codes for four proteins (Rep1, Rep2, Raf1, and Flp) vital for its own survival and recruits several host factors (RSC2, Cohesin, Cse4, Kip1, Bik1, Bim1, and microtubules) for its faithful segregation during cell division. The plasmid maintains a high-copy number with the help of Flp-mediated recombination. The plasmids organize in the form of clusters that hitch-hike the host chromosomes presumably with the help of the plasmid-encoded Rep proteins and host factors such as microtubules, Kip1 motor, and microtubule-associated proteins Bik1 and Bim1. Although there is no known yeast cell phenotype associated with the 2 micron plasmid, excessive copies of the plasmid are lethal for the cells, warranting a tight control over the plasmid copy number. This control is achieved through a combination of feedback loops involving the 2 micron encoded proteins. Thus, faithful segregation and a concomitant tightly controlled plasmid copy number ensure an optimized benign parasitism of the 2 micron plasmid within budding yeast.
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Affiliation(s)
- Syed Meraj Azhar Rizvi
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, 400076, India
| | - Hemant Kumar Prajapati
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, 400076, India
| | - Santanu Kumar Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, 400076, India.
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9
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Pelé A, Falque M, Trotoux G, Eber F, Nègre S, Gilet M, Huteau V, Lodé M, Jousseaume T, Dechaumet S, Morice J, Poncet C, Coriton O, Martin OC, Rousseau-Gueutin M, Chèvre AM. Amplifying recombination genome-wide and reshaping crossover landscapes in Brassicas. PLoS Genet 2017; 13:e1006794. [PMID: 28493942 PMCID: PMC5444851 DOI: 10.1371/journal.pgen.1006794] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 05/25/2017] [Accepted: 05/02/2017] [Indexed: 11/19/2022] Open
Abstract
Meiotic recombination by crossovers (COs) is tightly regulated, limiting its key role in producing genetic diversity. However, while COs are usually restricted in number and not homogenously distributed along chromosomes, we show here how to disrupt these rules in Brassica species by using allotriploid hybrids (AAC, 2n = 3x = 29), resulting from the cross between the allotetraploid rapeseed (B. napus, AACC, 2n = 4x = 38) and one of its diploid progenitors (B. rapa, AA, 2n = 2x = 20). We produced mapping populations from different genotypes of both diploid AA and triploid AAC hybrids, used as female and/or as male. Each population revealed nearly 3,000 COs that we studied with SNP markers well distributed along the A genome (on average 1 SNP per 1.25 Mbp). Compared to the case of diploids, allotriploid hybrids showed 1.7 to 3.4 times more overall COs depending on the sex of meiosis and the genetic background. Most surprisingly, we found that such a rise was always associated with (i) dramatic changes in the shape of recombination landscapes and (ii) a strong decrease of CO interference. Hybrids carrying an additional C genome exhibited COs all along the A chromosomes, even in the vicinity of centromeres that are deprived of COs in diploids as well as in most studied species. Moreover, in male allotriploid hybrids we found that Class I COs are mostly responsible for the changes of CO rates, landscapes and interference. These results offer the opportunity for geneticists and plant breeders to dramatically enhance the generation of diversity in Brassica species by disrupting the linkage drag coming from limits on number and distribution of COs.
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Affiliation(s)
- Alexandre Pelé
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Matthieu Falque
- GQE-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif sur Yvette, France
| | - Gwenn Trotoux
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Frédérique Eber
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Sylvie Nègre
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Marie Gilet
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Virginie Huteau
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Maryse Lodé
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | | | - Sylvain Dechaumet
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Jérôme Morice
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | | | - Olivier Coriton
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
| | - Olivier C. Martin
- GQE-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif sur Yvette, France
| | | | - Anne-Marie Chèvre
- IGEPP, INRA, Agrocampus Ouest, Université de Rennes 1, Le Rheu, France
- * E-mail:
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10
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Misawa K. Short tandem repeats in the human, cow, mouse, chicken, and lizard genomes are concentrated in the terminal regions of chromosomes. GENE REPORTS 2016. [DOI: 10.1016/j.genrep.2016.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Zhu Z, Gui S, Jin J, Yi R, Wu Z, Qian Q, Ding Y. The NnCenH3 protein and centromeric DNA sequence profiles of Nelumbo nucifera Gaertn. (sacred lotus) reveal the DNA structures and dynamics of centromeres in basal eudicots. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:568-582. [PMID: 27227686 DOI: 10.1111/tpj.13219] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/15/2016] [Accepted: 05/23/2016] [Indexed: 06/05/2023]
Abstract
Centromeres on eukaryotic chromosomes consist of large arrays of DNA repeats that undergo very rapid evolution. Nelumbo nucifera Gaertn. (sacred lotus) is a phylogenetic relict and an aquatic perennial basal eudicot. Studies concerning the centromeres of this basal eudicot species could provide ancient evolutionary perspectives. In this study, we characterized the centromeric marker protein NnCenH3 (sacred lotus centromere-specific histone H3 variant), and used a chromatin immunoprecipitation (ChIP)-based technique to recover the NnCenH3 nucleosome-associated sequences of sacred lotus. The properties of the centromere-binding protein and DNA sequences revealed notable divergence between sacred lotus and other flowering plants, including the following factors: (i) an NnCenH3 alternative splicing variant comprising only a partial centromere-targeting domain, (ii) active genes with low transcription levels in the NnCenH3 nucleosomal regions, and (iii) the prevalence of the Ty1/copia class of long terminal repeat (LTR) retrotransposons in the centromeres of sacred lotus chromosomes. In addition, the dynamic natures of the centromeric region showed that some of the centromeric repeat DNA sequences originated from telomeric repeats, and a pair of centromeres on the dicentric chromosome 1 was inactive in the metaphase cells of sacred lotus. Our characterization of the properties of centromeric DNA structure within the sacred lotus genome describes a centromeric profile in ancient basal eudicots and might provide evidence of the origins and evolution of centromeres. Furthermore, the identification of centromeric DNA sequences is of great significance for the assembly of the sacred lotus genome.
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Affiliation(s)
- Zhixuan Zhu
- Department of Genetics, State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Songtao Gui
- Department of Genetics, State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Jing Jin
- Department of Genetics, State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Rong Yi
- Department of Genetics, State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Zhihua Wu
- Department of Genetics, State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Qian Qian
- Department of Genetics, State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yi Ding
- Department of Genetics, State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
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Neumann P, Pavlíková Z, Koblížková A, Fuková I, Jedličková V, Novák P, Macas J. Centromeres Off the Hook: Massive Changes in Centromere Size and Structure Following Duplication of CenH3 Gene in Fabeae Species. Mol Biol Evol 2015; 32:1862-79. [PMID: 25771197 PMCID: PMC4476163 DOI: 10.1093/molbev/msv070] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In most eukaryotes, centromere is determined by the presence of the centromere-specific histone variant CenH3. Two types of chromosome morphology are generally recognized with respect to centromere organization. Monocentric chromosomes possess a single CenH3-containing domain in primary constriction, whereas holocentric chromosomes lack the primary constriction and display dispersed distribution of CenH3. Recently, metapolycentric chromosomes have been reported in Pisum sativum, representing an intermediate type of centromere organization characterized by multiple CenH3-containing domains distributed across large parts of chromosomes that still form a single constriction. In this work, we show that this type of centromere is also found in other Pisum and closely related Lathyrus species, whereas Vicia and Lens genera, which belong to the same legume tribe Fabeae, possess only monocentric chromosomes. We observed extensive variability in the size of primary constriction and the arrangement of CenH3 domains both between and within individual Pisum and Lathyrus species, with no obvious correlation to genome or chromosome size. Search for CenH3 gene sequences revealed two paralogous variants, CenH3-1 and CenH3-2, which originated from a duplication event in the common ancestor of Fabeae species. The CenH3-1 gene was subsequently lost or silenced in the lineage leading to Vicia and Lens, whereas both genes are retained in Pisum and Lathyrus. Both of these genes appear to have evolved under purifying selection and produce functional CenH3 proteins which are fully colocalized. The findings described here provide the first evidence for a highly dynamic centromere structure within a group of closely related species, challenging previous concepts of centromere evolution.
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Affiliation(s)
- Pavel Neumann
- Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Zuzana Pavlíková
- Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Andrea Koblížková
- Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Iva Fuková
- Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Veronika Jedličková
- Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Petr Novák
- Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Jiří Macas
- Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
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Abstract
The budding yeast Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of eukaryotic cell biology. This Primer article presents a brief historical perspective on the emergence of this organism as a premier experimental system over the course of the past century. An overview of the central features of the S. cerevisiae genome, including the nature of its genetic elements and general organization, is also provided. Some of the most common experimental tools and resources available to yeast geneticists are presented in a way designed to engage and challenge undergraduate and graduate students eager to learn more about the experimental amenability of budding yeast. Finally, a discussion of several major discoveries derived from yeast studies highlights the far-reaching impact that the yeast system has had and will continue to have on our understanding of a variety of cellular processes relevant to all eukaryotes, including humans.
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Blanc G, Agarkova I, Grimwood J, Kuo A, Brueggeman A, Dunigan DD, Gurnon J, Ladunga I, Lindquist E, Lucas S, Pangilinan J, Pröschold T, Salamov A, Schmutz J, Weeks D, Yamada T, Lomsadze A, Borodovsky M, Claverie JM, Grigoriev IV, Van Etten JL. The genome of the polar eukaryotic microalga Coccomyxa subellipsoidea reveals traits of cold adaptation. Genome Biol 2012; 13:R39. [PMID: 22630137 PMCID: PMC3446292 DOI: 10.1186/gb-2012-13-5-r39] [Citation(s) in RCA: 198] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 05/15/2012] [Accepted: 05/25/2012] [Indexed: 12/27/2022] Open
Abstract
Background Little is known about the mechanisms of adaptation of life to the extreme environmental conditions encountered in polar regions. Here we present the genome sequence of a unicellular green alga from the division chlorophyta, Coccomyxa subellipsoidea C-169, which we will hereafter refer to as C-169. This is the first eukaryotic microorganism from a polar environment to have its genome sequenced. Results The 48.8 Mb genome contained in 20 chromosomes exhibits significant synteny conservation with the chromosomes of its relatives Chlorella variabilis and Chlamydomonas reinhardtii. The order of the genes is highly reshuffled within synteny blocks, suggesting that intra-chromosomal rearrangements were more prevalent than inter-chromosomal rearrangements. Remarkably, Zepp retrotransposons occur in clusters of nested elements with strictly one cluster per chromosome probably residing at the centromere. Several protein families overrepresented in C. subellipsoidae include proteins involved in lipid metabolism, transporters, cellulose synthases and short alcohol dehydrogenases. Conversely, C-169 lacks proteins that exist in all other sequenced chlorophytes, including components of the glycosyl phosphatidyl inositol anchoring system, pyruvate phosphate dikinase and the photosystem 1 reaction center subunit N (PsaN). Conclusions We suggest that some of these gene losses and gains could have contributed to adaptation to low temperatures. Comparison of these genomic features with the adaptive strategies of psychrophilic microbes suggests that prokaryotes and eukaryotes followed comparable evolutionary routes to adapt to cold environments.
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Affiliation(s)
- Guillaume Blanc
- Structural and Genomic Information Laboratory, UMR7256 CNRS, Aix-Marseille University, Mediterranean Institute of Microbiology (FR3479), Marseille, FR-13385, France.
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15
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Echeverry MC, Bot C, Obado SO, Taylor MC, Kelly JM. Centromere-associated repeat arrays on Trypanosoma brucei chromosomes are much more extensive than predicted. BMC Genomics 2012; 13:29. [PMID: 22257693 PMCID: PMC3292466 DOI: 10.1186/1471-2164-13-29] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 01/18/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND African trypanosomes belong to a eukaryotic lineage which displays many unusual genetic features. The mechanisms of chromosome segregation in these diploid protozoan parasites are poorly understood. Centromeres in Trypanosoma brucei have been localised to chromosomal regions that contain an array of ~147 bp AT-rich tandem repeats. Initial estimates from the genome sequencing project suggested that these arrays ranged from 2 - 8 kb. In this paper, we show that the centromeric repeat regions are much more extensive. RESULTS We used a long-range restriction endonuclease mapping approach to more accurately define the sizes of the centromeric repeat arrays on the 8 T. brucei chromosomes where unambiguous assembly data were available. The results indicate that the sizes of the arrays on different chromosomes vary from 20 to 120 kb. In addition, we found instances of length heterogeneity between chromosome homologues. For example, values of 20 and 65 kb were obtained for the arrays on chromosome 1, and 50 and 75 kb for chromosome 5. CONCLUSIONS Our results show that centromeric repeat arrays on T. brucei chromosomes are more similar in size to those of higher eukaryotes than previously suspected. This information provides a firmer framework for investigating aspects of chromosome segregation and will allow epigenetic features associated with the process to be more accurately mapped.
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Affiliation(s)
- Maria C Echeverry
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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Schenkman S, Pascoalino BDS, Nardelli SC. Nuclear structure of Trypanosoma cruzi. ADVANCES IN PARASITOLOGY 2011; 75:251-83. [PMID: 21820560 DOI: 10.1016/b978-0-12-385863-4.00012-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The presence of nucleus in living organisms characterizes the Eukaryote domain. The nucleus compartmentalizes the genetic material surrounded by a double membrane called nuclear envelope. The nucleus has been observed since the advent of the light microscope, and sub-compartments such as nucleoli, diverse nuclear bodies and condensed chromosomes have been later recognized, being part of highly organized and dynamic structure. The significance and function of such organization has increased with the understanding of transcription, replication, DNA repair, recombination processes. It is now recognized as consequence of adding complexity and regulation in more complex eukaryotic cells. Here we provide a description of the actual stage of knowledge of the nuclear structure of Trypanosoma cruzi. As an early divergent eukaryote, it presents unique and/or reduced events of DNA replication, transcription and repair as well as RNA processing and transport to the cytosol. Nevertheless, it shows peculiar structure changes accordingly to the cell cycle and stage of differentiation. T. cruzi proliferates only as epimastigote and amastigote stages, and when these forms differentiate in trypomastigote forms, their cell cycle is arrested. This arrested stage is capable of invading mammalian cells and of surviving harsh conditions, such as the gut of the insect vector and mammalian macrophages. Transcription and replication decrease during transformation in trypomastigotes implicating large alterations in the nuclear structure. Recent evidences also suggest that T. cruzi nucleus respond to oxidative and nutritional stresses. Due to the phylogenetic proximity with other well-known trypanosomes, such as Trypanosoma brucei and Leishmania major, they are expected to have similar nuclear organization, although differences are noticed due to distinct life cycles, cellular organizations and the specific adaptations for surviving in different host environments. Therefore, the general features of T. cruzi nuclear structure regarding unique characteristics of this protozoan parasite will be described.
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Affiliation(s)
- Sergio Schenkman
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil
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Loss of centromeric histone H3 (CENH3) from centromeres precedes uniparental chromosome elimination in interspecific barley hybrids. Proc Natl Acad Sci U S A 2011; 108:E498-505. [PMID: 21746892 DOI: 10.1073/pnas.1103190108] [Citation(s) in RCA: 174] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Uniparental chromosome elimination occurs in several interspecific hybrids of plants. We studied the mechanism underlying selective elimination of the paternal chromosomes during the early development of Hordeum vulgare × Hordeum bulbosum embryos. The following conclusions regarding the role of the centromere-specific histone H3 variant (CENH3) in the process of chromosome elimination were drawn: (i) centromere inactivity of H. bulbosum chromosomes triggers the mitosis-dependent process of uniparental chromosome elimination in unstable H. vulgare × H. bulbosum hybrids; (ii) centromeric loss of CENH3 protein rather than uniparental silencing of CENH3 genes causes centromere inactivity; (iii) in stable species combinations, cross-species incorporation of CENH3 occurs despite centromere-sequence differences, and not all CENH3 variants get incorporated into centromeres if multiple CENH3s are present in species combinations; and (iv) diploid barley species encode two CENH3 variants, the proteins of which are intermingled within centromeres throughout mitosis and meiosis.
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18
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Houben A, Kumke K, Nagaki K, Hause G. CENH3 distribution and differential chromatin modifications during pollen development in rye (Secale cereale L.). Chromosome Res 2011; 19:471-80. [PMID: 21503764 DOI: 10.1007/s10577-011-9207-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 02/24/2011] [Accepted: 02/24/2011] [Indexed: 11/30/2022]
Abstract
Microgametogenesis in angiosperms results in two structurally and functionally different cells, one generative cell, which subsequently forms the sperm cells, and the vegetative cell. We analysed the chromatin properties of both types of nuclei after first and second pollen mitosis in rye (Secale cereale). The condensed chromatin of generative nuclei is earmarked by an enhanced level of histone H3K4/K9 dimethylation and H3K9 acetylation. The less condensed vegetative nuclei are RNA polymerase II positive. Trimethylation of H3K27 is not involved in transcriptional downregulation of genes located in generative nuclei as H3K27me3 was exclusively detected in the vegetative nuclei. The global level of DNA methylation does not differ between both types of pollen nuclei. In rye, unlike in Arabidopsis thaliana (Ingouff et al. Curr Biol 17:1032-1037 2007; Schoft et al. EMBO Rep 10:1015-1021 2009), centromeric histone H3 is not excluded from the chromatin of the vegetative nucleus and the condensation degree of centromeric and subtelomeric regions did not differ between the generative and vegetative nuclei. Differences between rye and A. thaliana data suggest that the chromatin organization in mature nuclei of pollen grains is not universal across angiosperms.
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Affiliation(s)
- Andreas Houben
- Leibniz Institute of Plant Genetics and Crop Plant Research, Corrensstr. 3, 06466, Gatersleben, Germany.
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19
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Li LC, Han FP. [Advances and perspectives in artificial chromosomes]. YI CHUAN = HEREDITAS 2011; 33:293-7. [PMID: 21482517 DOI: 10.3724/sp.j.1005.2011.00293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Artificial chromosomes (ACs) are genetic-engineered vector systems with defined native chromosomal elements. ACs have large carrying capacity and genetic stability without integration into host genome, thus avoiding random insertion and positional effects. ACs were first successfully developed in yeast (Yeast artificial chromosome, YAC), and then in bacterium (Bacterial artificial chromosome, BAC), human (Human artificial chromosome, HAC), and plant (Plant artificial chromosome, PAC). Here, we summarized recent progress on ACs, especially, on PAC. To date, YAC and BAC have been widely applied in genome sequencing and gene isolation, while HAC and PAC have been subjected to gene therapy, protein production, and plant transgenesis, respectively. Recently, American scientists reported a man-made genome of prokaryote Mycoplasma mycoides. However, like ACs, this man-made genome was also genetic-engineered product and can't survive as an independent life without a cellular environment.
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Affiliation(s)
- Lin-Chuan Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
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