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Hjelmen CE, Holmes VR, Burrus CG, Piron E, Mynes M, Garrett MA, Blackmon H, Johnston JS. Thoracic underreplication in Drosophila species estimates a minimum genome size and the dynamics of added DNA. Evolution 2020; 74:1423-1436. [PMID: 32438451 DOI: 10.1111/evo.14022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 05/05/2020] [Accepted: 05/17/2020] [Indexed: 12/11/2022]
Abstract
Many cells in the thorax of Drosophila were found to stall during replication, a phenomenon known as underreplication. Unlike underreplication in nuclei of salivary and follicle cells, this stall occurs with less than one complete round of replication. This stall point allows precise estimations of early-replicating euchromatin and late-replicating heterochromatin regions, providing a powerful tool to investigate the dynamics of structural change across the genome. We measure underreplication in 132 species across the Drosophila genus and leverage these data to propose a model for estimating the rate at which additional DNA is accumulated as heterochromatin and euchromatin and also predict the minimum genome size for Drosophila. According to comparative phylogenetic approaches, the rates of change of heterochromatin differ strikingly between Drosophila subgenera. Although these subgenera differ in karyotype, there were no differences by chromosome number, suggesting other structural changes may influence accumulation of heterochromatin. Measurements were taken for both sexes, allowing the visualization of genome size and heterochromatin changes for the hypothetical path of XY sex chromosome differentiation. Additionally, the model presented here estimates a minimum genome size in Sophophora remarkably close to the smallest insect genome measured to date, in a species over 200 million years diverged from Drosophila.
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Affiliation(s)
- Carl E Hjelmen
- Department of Biology, Texas A&M University, College Station, Texas.,Department of Entomology, Texas A&M University, College Station, Texas
| | | | - Crystal G Burrus
- Department of Biology, Texas A&M University, College Station, Texas
| | - Elizabeth Piron
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas
| | - Melissa Mynes
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas
| | - Margaret A Garrett
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas
| | - Heath Blackmon
- Department of Biology, Texas A&M University, College Station, Texas
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2
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Pokholkova GV, Demakov SA, Andreenkov OV, Andreenkova NG, Volkova EI, Belyaeva ES, Zhimulev IF. Tethering of CHROMATOR and dCTCF proteins results in decompaction of condensed bands in the Drosophila melanogaster polytene chromosomes but does not affect their transcription and replication timing. PLoS One 2018; 13:e0192634. [PMID: 29608600 PMCID: PMC5880345 DOI: 10.1371/journal.pone.0192634] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/26/2018] [Indexed: 01/20/2023] Open
Abstract
Instulator proteins are central to domain organization and gene regulation in the genome. We used ectopic tethering of CHROMATOR (CHRIZ/CHRO) and dCTCF to pre-defined regions of the genome to dissect the influence of these proteins on local chromatin organization, to analyze their interaction with other key chromatin proteins and to evaluate the effects on transcription and replication. Specifically, using UAS-GAL4DBD system, CHRO and dCTCF were artificially recruited into highly compacted polytene chromosome bands that share the features of silent chromatin type known as intercalary heterochromatin (IH). This led to local chromatin decondensation, formation of novel DHSes and recruitment of several "open chromatin" proteins. CHRO tethering resulted in the recruitment of CP190 and Z4 (PZG), whereas dCTCF tethering attracted CHRO, CP190, and Z4. Importantly, formation of a local stretch of open chromatin did not result in the reactivation of silent marker genes yellow and mini-white immediately adjacent to the targeting region (UAS), nor did RNA polII become recruited into this chromatin. The decompacted region retained late replicated, similarly to the wild-type untargeted region.
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Affiliation(s)
- Galina V. Pokholkova
- Institute of Molecular and Cellular Biology of the Siberian Branch of the Russian Academy of Sciences (IMCB RAS), Novosibirsk, Russia
| | - Sergei A. Demakov
- Institute of Molecular and Cellular Biology of the Siberian Branch of the Russian Academy of Sciences (IMCB RAS), Novosibirsk, Russia
- Novosibirsk State University (NSU), Novosibirsk, Russia
| | - Oleg V. Andreenkov
- Institute of Molecular and Cellular Biology of the Siberian Branch of the Russian Academy of Sciences (IMCB RAS), Novosibirsk, Russia
| | - Natalia G. Andreenkova
- Institute of Molecular and Cellular Biology of the Siberian Branch of the Russian Academy of Sciences (IMCB RAS), Novosibirsk, Russia
| | - Elena I. Volkova
- Institute of Molecular and Cellular Biology of the Siberian Branch of the Russian Academy of Sciences (IMCB RAS), Novosibirsk, Russia
| | - Elena S. Belyaeva
- Institute of Molecular and Cellular Biology of the Siberian Branch of the Russian Academy of Sciences (IMCB RAS), Novosibirsk, Russia
| | - Igor F. Zhimulev
- Institute of Molecular and Cellular Biology of the Siberian Branch of the Russian Academy of Sciences (IMCB RAS), Novosibirsk, Russia
- Novosibirsk State University (NSU), Novosibirsk, Russia
- * E-mail:
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3
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Penke TJR, McKay DJ, Strahl BD, Matera AG, Duronio RJ. Functional Redundancy of Variant and Canonical Histone H3 Lysine 9 Modification in Drosophila. Genetics 2018; 208:229-244. [PMID: 29133298 PMCID: PMC5753860 DOI: 10.1534/genetics.117.300480] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 11/10/2017] [Indexed: 01/07/2023] Open
Abstract
Histone post-translational modifications (PTMs) and differential incorporation of variant and canonical histones into chromatin are central modes of epigenetic regulation. Despite similar protein sequences, histone variants are enriched for different suites of PTMs compared to their canonical counterparts. For example, variant histone H3.3 occurs primarily in transcribed regions and is enriched for "active" histone PTMs like Lys9 acetylation (H3.3K9ac), whereas the canonical histone H3 is enriched for Lys9 methylation (H3K9me), which is found in transcriptionally silent heterochromatin. To determine the functions of K9 modification on variant vs. canonical H3, we compared the phenotypes caused by engineering H3.3K9R and H3K9R mutant genotypes in Drosophila melanogaster Whereas most H3.3K9R , and a small number of H3K9R , mutant animals are capable of completing development and do not have substantially altered protein-coding transcriptomes, all H3.3K9R H3K9R combined mutants die soon after embryogenesis and display decreased expression of genes enriched for K9ac. These data suggest that the role of K9ac in gene activation during development can be provided by either H3 or H3.3. Conversely, we found that H3.3K9 is methylated at telomeric transposons and that this mark contributes to repressive chromatin architecture, supporting a role for H3.3 in heterochromatin that is distinct from that of H3. Thus, our genetic and molecular analyses demonstrate that K9 modification of variant and canonical H3 have overlapping roles in development and transcriptional regulation, though to differing extents in euchromatin and heterochromatin.
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Affiliation(s)
- Taylor J R Penke
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
| | - Daniel J McKay
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, North Carolina 27599
- Department of Genetics, The University of North Carolina at Chapel Hill, North Carolina 27599
- Department of Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
| | - Brian D Strahl
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, North Carolina 27599
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, North Carolina 27599
| | - A Gregory Matera
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, North Carolina 27599
- Department of Genetics, The University of North Carolina at Chapel Hill, North Carolina 27599
- Department of Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, North Carolina 27599
| | - Robert J Duronio
- Curriculum in Genetics and Molecular Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, North Carolina 27599
- Department of Genetics, The University of North Carolina at Chapel Hill, North Carolina 27599
- Department of Biology, The University of North Carolina at Chapel Hill, North Carolina 27599
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, North Carolina 27599
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Chatterjee RN. Dosage compensation and its roles in evolution of sex chromosomes and phenotypic dimorphism: lessons from Drosophila, C.elegans and mammals. THE NUCLEUS 2017. [DOI: 10.1007/s13237-017-0223-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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5
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Hoffmann RF, Moshkin YM, Mouton S, Grzeschik NA, Kalicharan RD, Kuipers J, Wolters AHG, Nishida K, Romashchenko AV, Postberg J, Lipps H, Berezikov E, Sibon OCM, Giepmans BNG, Lansdorp PM. Guanine quadruplex structures localize to heterochromatin. Nucleic Acids Res 2015; 44:152-63. [PMID: 26384414 PMCID: PMC4705689 DOI: 10.1093/nar/gkv900] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/21/2015] [Indexed: 12/27/2022] Open
Abstract
Increasing amounts of data support a role for guanine quadruplex (G4) DNA and RNA structures in various cellular processes. We stained different organisms with monoclonal antibody 1H6 specific for G4 DNA. Strikingly, immuno-electron microscopy showed exquisite specificity for heterochromatin. Polytene chromosomes from Drosophila salivary glands showed bands that co-localized with heterochromatin proteins HP1 and the SNF2 domain-containing protein SUUR. Staining was retained in SUUR knock-out mutants but lost upon overexpression of SUUR. Somatic cells in Macrostomum lignano were strongly labeled, but pluripotent stem cells labeled weakly. Similarly, germline stem cells in Drosophila ovaries were weakly labeled compared to most other cells. The unexpected presence of G4 structures in heterochromatin and the difference in G4 staining between somatic cells and stem cells with germline DNA in ciliates, flatworms, flies and mammals point to a conserved role for G4 structures in nuclear organization and cellular differentiation.
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Affiliation(s)
- Roland F Hoffmann
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Yuri M Moshkin
- Department of Biochemistry, Erasmus University Medical Center, Dr. Molewaterplein 50, NL-3015 GE Rotterdam, The Netherlands
| | - Stijn Mouton
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Nicola A Grzeschik
- Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Ruby D Kalicharan
- Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Jeroen Kuipers
- Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Anouk H G Wolters
- Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Kazuki Nishida
- Faculty of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Aleksander V Romashchenko
- Department of Biochemistry, Erasmus University Medical Center, Dr. Molewaterplein 50, NL-3015 GE Rotterdam, The Netherlands Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Jan Postberg
- Helios Medical Centre Wuppertal, Paediatrics Centre, Witten/Herdecke University, Wuppertal, Germany
| | - Hans Lipps
- Institute of Cell Biology, Centre for Biomedical Education and Research, Witten/Herdecke University, Witten, Germany
| | - Eugene Berezikov
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Ody C M Sibon
- Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Ben N G Giepmans
- Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands
| | - Peter M Lansdorp
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands Terry Fox Laboratory, British Columbia Cancer Agency and Department of Medicine, University of British Columbia Vancouver, BC, V5Z 1L3, Canada
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6
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Ming L, Wilk R, Reed BH, Lipshitz HD. Drosophila Hindsight and mammalian RREB-1 are evolutionarily conserved DNA-binding transcriptional attenuators. Differentiation 2014; 86:159-70. [PMID: 24418439 DOI: 10.1016/j.diff.2013.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 10/25/2013] [Accepted: 12/05/2013] [Indexed: 12/22/2022]
Abstract
The Drosophila Hindsight (hnt) gene encodes a C2H2-type Zinc-finger protein, HNT, that plays multiple developmental roles including control of embryonic germ band retraction and regulation of retinal cell fate and morphogenesis. While the developmental functions of the human HNT homolog, RREB-1, are unknown, it has been shown to function as a transcriptional modulator of several tumor suppressor genes. Here we investigate HNT's functional motifs, target genes and its regulatory abilities. We show that the C-terminal region of HNT, containing the last five of its 14 Zinc fingers, binds in vitro to DNA elements very similar to those identified for RREB-1. We map HNT's in vivo binding sites on salivary gland polytene chromosomes and define, at high resolution, where HNT is bound to two target genes, hnt itself and nervy (nvy). Data from both loss-of-function and over-expression experiments show that HNT attenuates the transcription of these two targets in a tissue-specific manner. RREB-1, when expressed in Drosophila, binds to the same polytene chromosome sites as HNT, attenuates expression of the hnt and nvy genes, and rescues the germ band retraction phenotype. HNT's ninth Zinc finger has degenerated or been lost in the vertebrate lineage. We show that a HNT protein mutant for this finger can also attenuate target gene expression and rescue germ band retraction. Thus HNT and RREB-1 are functional homologs at the level of DNA binding, transcriptional regulation and developmental control.
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Affiliation(s)
- Liang Ming
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8.
| | - Ronit Wilk
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8.
| | - Bruce H Reed
- Department of Biology, University of Waterloo, 200 University Avenue W, Waterloo, Ontario, Canada N2L 3G1.
| | - Howard D Lipshitz
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8.
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7
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Kolesnikova TD, Posukh OV, Andreyeva EN, Bebyakina DS, Ivankin AV, Zhimulev IF. Drosophila SUUR protein associates with PCNA and binds chromatin in a cell cycle-dependent manner. Chromosoma 2012; 122:55-66. [DOI: 10.1007/s00412-012-0390-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 09/25/2012] [Accepted: 10/22/2012] [Indexed: 01/06/2023]
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8
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Nowak SJ, Aihara H, Gonzalez K, Nibu Y, Baylies MK. Akirin links twist-regulated transcription with the Brahma chromatin remodeling complex during embryogenesis. PLoS Genet 2012; 8:e1002547. [PMID: 22396663 PMCID: PMC3291577 DOI: 10.1371/journal.pgen.1002547] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 01/04/2012] [Indexed: 11/19/2022] Open
Abstract
The activities of developmentally critical transcription factors are regulated via interactions with cofactors. Such interactions influence transcription factor activity either directly through protein–protein interactions or indirectly by altering the local chromatin environment. Using a yeast double-interaction screen, we identified a highly conserved nuclear protein, Akirin, as a novel cofactor of the key Drosophila melanogaster mesoderm and muscle transcription factor Twist. We find that Akirin interacts genetically and physically with Twist to facilitate expression of some, but not all, Twist-regulated genes during embryonic myogenesis. akirin mutant embryos have muscle defects consistent with altered regulation of a subset of Twist-regulated genes. To regulate transcription, Akirin colocalizes and genetically interacts with subunits of the Brahma SWI/SNF-class chromatin remodeling complex. Our results suggest that, mechanistically, Akirin mediates a novel connection between Twist and a chromatin remodeling complex to facilitate changes in the chromatin environment, leading to the optimal expression of some Twist-regulated genes during Drosophila myogenesis. We propose that this Akirin-mediated link between transcription factors and the Brahma complex represents a novel paradigm for providing tissue and target specificity for transcription factor interactions with the chromatin remodeling machinery. The proper development of the diverse array of cell types in an organism depends upon the induction and repression of specific genes at particular times and places. This gene regulation requires both the activity of tissue-specific transcriptional regulators and the modulation of the chromatin environment. To date, a complete picture of the interplay between these two processes remains unclear. To address this, we examined the activity of the evolutionarily conserved transcription factor Twist during embryogenesis of Drosophila melanogaster. While Twist has multiple activities and roles during development, a direct link between Twist and chromatin remodeling is unknown. We identified a highly conserved protein, Akirin, as a link between Twist and chromatin remodeling factors. Akirin is required for optimal expression of a Twist-dependent target during muscle development via interactions with the Drosophila SWI/SNF chromatin remodeling complex. Interestingly, Akirin is not required for activation of all Twist-dependent enhancers, suggesting that Akirin refines Twist activity outputs and that different Twist-dependent targets have different requirements for chromatin remodeling during development. Our data further suggests that Akirin similarly links the SWI/SNF chromatin remodeling complex with other transcription factors during development. This work has important ramifications for understanding both normal development and diseases such as cancer.
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Affiliation(s)
- Scott J. Nowak
- Program in Developmental Biology, Sloan Kettering Institute, New York, New York, United States of America
| | - Hitoshi Aihara
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, United States of America
| | - Katie Gonzalez
- Weill Cornell Graduate School of Biomedical Sciences, Cornell University, New York, New York, United States of America
| | - Yutaka Nibu
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, United States of America
- Weill Cornell Graduate School of Biomedical Sciences, Cornell University, New York, New York, United States of America
| | - Mary K. Baylies
- Program in Developmental Biology, Sloan Kettering Institute, New York, New York, United States of America
- Weill Cornell Graduate School of Biomedical Sciences, Cornell University, New York, New York, United States of America
- * E-mail:
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9
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Andreyenkova NG, Kokoza EB, Semeshin VF, Belyaeva ES, Demakov SA, Pindyurin AV, Andreyeva EN, Volkova EI, Zhimulev IF. Localization and characteristics of DNA underreplication zone in the 75C region of intercalary heterochromatin in Drosophila melanogaster polytene chromosomes. Chromosoma 2009; 118:747-61. [PMID: 19685068 DOI: 10.1007/s00412-009-0232-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Revised: 07/16/2009] [Accepted: 07/22/2009] [Indexed: 10/20/2022]
Abstract
In Drosophila polytene chromosomes, regions of intercalary heterochromatin are scattered throughout the euchromatic arms. Here, we present data on the first fine analysis of the individual intercalary heterochromatin region, 75C1-2, located in the 3L chromosome. By using electron microscopy, we demonstrated that this region appears as three closely adjacent condensed bands. Mapping of the region on the physical map by means of the chromosomal rearrangements with known breakpoints showed that the length of the region is about 445 kb. Although it seems that the SUUR protein binds to the whole 75C1-2 region, the proximal part of the region is fully polytenized, so the DNA underreplication zone is asymmetric and located in the distal half of the region. Finally, we speculate that intercalary heterochromatin regions of Drosophila polytene chromosomes are organized into three different types with respect to the localization of the underreplication zone.
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Affiliation(s)
- Natalya G Andreyenkova
- Department of Molecular and Cellular Biology, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, Novosibirsk, Russia
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10
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Kokoza EB, Kolesnikova TD, Zykov IA, Belyaeva ES, Zhimulev IF. Reversible decondensation of heterochromatin regions of Drosophila melanogaster polytene chromosomes during ectopic expression of the SuUR gene. DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2009; 426:244-6. [PMID: 19650328 DOI: 10.1134/s0012496609030156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- E B Kokoza
- Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, ul. Akademika Lavrent'eva 10, Novosibirsk, 630090 Russia
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11
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Conservation of domain structure in a fast-evolving heterochromatic SUUR protein in drosophilids. Genetics 2009; 183:119-29. [PMID: 19596903 DOI: 10.1534/genetics.109.104844] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Different genomic regions replicate at a distinct time during S-phase. The SuUR mutation alters replication timing and the polytenization level of intercalary and pericentric heterochromatin in Drosophila melanogaster salivary gland polytene chromosomes. We analyzed SuUR in different insects, identified conserved regions in the protein, substituted conserved amino acid residues, and studied effects of the mutations on SUUR function. SuUR orthologs were identified in all sequenced drosophilids, and a highly divergent ortholog was found in the mosquito genome. We demonstrated that SUUR evolves at very high rate comparable with that of Transformer. Remarkably, upstream ORF within 5' UTR of the gene is more conserved than SUUR in drosophilids, but it is absent in the mosquito. The domain structure and charge of SUUR are maintained in drosophilids despite the high divergence of the proteins. The N-terminal part of SUUR with similarity to the SNF2/SWI2 proteins displays the highest level of conservation. Mutation of two conserved amino acid residues in this region impairs binding of SUUR to polytene chromosomes and reduces the ability of the protein to cause DNA underreplication. The least conserved middle part of SUUR interacting with HP1 retains positively and negatively charged clusters and nuclear localization signals. The C terminus contains interlacing conserved and variable motifs. Our results suggest that SUUR domains evolve with different rates and patterns but maintain their features.
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12
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Peng YH, Yang WK, Lin WH, Lai TT, Chien CT. Nak regulates Dlg basal localization in Drosophila salivary gland cells. Biochem Biophys Res Commun 2009; 382:108-13. [PMID: 19258011 DOI: 10.1016/j.bbrc.2009.02.139] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Accepted: 02/25/2009] [Indexed: 01/10/2023]
Abstract
Protein trafficking is highly regulated in polarized cells. During development, how the trafficking of cell junctional proteins is regulated for cell specialization is largely unknown. In the maturation of Drosophila larval salivary glands (SGs), the Dlg protein is essential for septate junction formation. We show that Dlg was enriched in the apical membrane domain of proximal cells and localized basolaterally in distal mature cells. The transition of Dlg distribution was disrupted in nak mutants. Nak associated with the AP-2 subunit alpha-Ada and the AP-1 subunit AP-1gamma. In SG cells disrupting AP-1 and AP-2 activities, Dlg was enriched in the apical membrane. Therefore, Nak regulates the transition of Dlg distribution likely through endocytosis of Dlg from the apical membrane domain and transcytosis of Dlg to the basolateral membrane domain during the maturation of SGs development.
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Affiliation(s)
- Yu-Huei Peng
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan
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13
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Eissenberg JC, Reuter G. Cellular mechanism for targeting heterochromatin formation in Drosophila. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 273:1-47. [PMID: 19215901 DOI: 10.1016/s1937-6448(08)01801-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Near the end of their 1990 historical perspective article "60 Years of Mystery," Spradling and Karpen (1990) observe: "Recent progress in understanding variegation at the molecular level has encouraged some workers to conclude that the heterochromatization model is essentially correct and that position-effect variegation can now join the mainstream of molecular biology." In the 18 years since those words were written, heterochromatin and its associated position effects have indeed joined the mainstream of molecular biology. Here, we review the findings that led to our current understanding of heterochromatin formation in Drosophila and the mechanistic insights into heterochromatin structural and functional properties gained through molecular genetics and cytology.
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Affiliation(s)
- Joel C Eissenberg
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
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14
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Doheny JG, Mottus R, Grigliatti TA. Telomeric position effect--a third silencing mechanism in eukaryotes. PLoS One 2008; 3:e3864. [PMID: 19057646 PMCID: PMC2587703 DOI: 10.1371/journal.pone.0003864] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Accepted: 10/20/2008] [Indexed: 12/29/2022] Open
Abstract
Eukaryotic chromosomes terminate in telomeres, complex nucleoprotein structures that are required for chromosome integrity that are implicated in cellular senescence and cancer. The chromatin at the telomere is unique with characteristics of both heterochromatin and euchromatin. The end of the chromosome is capped by a structure that protects the end and is required for maintaining proper chromosome length. Immediately proximal to the cap are the telomere associated satellite-like (TAS) sequences. Genes inserted into the TAS sequences are silenced indicating the chromatin environment is incompatible with transcription. This silencing phenomenon is called telomeric position effect (TPE). Two other silencing mechanisms have been identified in eukaryotes, suppressors position effect variegation [Su(var)s, greater than 30 members] and Polycomb group proteins (PcG, approximately 15 members). We tested a large number of each group for their ability to suppress TPE [Su(TPE)]. Our results showed that only three Su(var)s and only one PcG member are involved in TPE, suggesting silencing in the TAS sequences occurs via a novel silencing mechanism. Since, prior to this study, only five genes have been identified that are Su(TPE)s, we conducted a candidate screen for Su(TPE) in Drosophila by testing point mutations in, and deficiencies for, proteins involved in chromatin metabolism. Screening with point mutations identified seven new Su(TPE)s and the deficiencies identified 19 regions of the Drosophila genome that harbor suppressor mutations. Chromatin immunoprecipitation experiments on a subset of the new Su(TPE)s confirm they act directly on the gene inserted into the telomere. Since the Su(TPE)s do not overlap significantly with either PcGs or Su(var)s, and the candidates were selected because they are involved generally in chromatin metabolism and act at a wide variety of sites within the genome, we propose that the Su(TPE) represent a third, widely used, silencing mechanism in the eukaryotic genome.
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Affiliation(s)
- J. Greg Doheny
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Randy Mottus
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Thomas A. Grigliatti
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
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15
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Pindyurin AV, Boldyreva LV, Shloma VV, Kolesnikova TD, Pokholkova GV, Andreyeva EN, Kozhevnikova EN, Ivanoschuk IG, Zarutskaya EA, Demakov SA, Gorchakov AA, Belyaeva ES, Zhimulev IF. Interaction between theDrosophilaheterochromatin proteins SUUR and HP1. J Cell Sci 2008; 121:1693-703. [DOI: 10.1242/jcs.018655] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
SUUR (Suppressor of Under-Replication) protein is responsible for late replication and, as a consequence, for DNA underreplication of intercalary and pericentric heterochromatin in Drosophila melanogaster polytene chromosomes. However, the mechanism by which SUUR slows down the replication process is not clear. To identify possible partners for SUUR we performed a yeast two-hybrid screen using full-length SUUR as bait. This identified HP1, the well-studied heterochromatin protein, as a strong SUUR interactor. Furthermore, we have determined that the central region of SUUR is necessary and sufficient for interaction with the C-terminal part of HP1, which contains the hinge and chromoshadow domains. In addition, recruitment of SUUR to ectopic HP1 sites on chromosomes provides evidence for their association in vivo. Indeed, we found that the distributions of SUUR and HP1 on polytene chromosomes are interdependent: both absence and overexpression of HP1 prevent SUUR from chromosomal binding, whereas SUUR overexpression causes redistribution of HP1 to numerous sites occupied by SUUR. Finally, HP1 binds to intercalary heterochromatin when histone methyltransferase activity of SU(VAR)3-9 is increased. We propose that interaction with HP1 is crucial for the association of SUUR with chromatin.
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Affiliation(s)
- Alexey V. Pindyurin
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Lidiya V. Boldyreva
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Victor V. Shloma
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Tatiana D. Kolesnikova
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Department of Cytology and Genetics, Novosibirsk State University, Novosibirsk 630090, Russia
| | - Galina V. Pokholkova
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Evgeniya N. Andreyeva
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Elena N. Kozhevnikova
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Igor G. Ivanoschuk
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Ekaterina A. Zarutskaya
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Sergey A. Demakov
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Andrey A. Gorchakov
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Elena S. Belyaeva
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
| | - Igor F. Zhimulev
- Institute of Cytology and Genetics of Siberian Division, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Department of Cytology and Genetics, Novosibirsk State University, Novosibirsk 630090, Russia
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16
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Posukh OV, Yurlova AA, Belyaeva ES, Zhimulev IF. System for purification of complexes of the Drosophila melanogaster chromosomal protein SUUR. DOKL BIOCHEM BIOPHYS 2007; 416:274-7. [DOI: 10.1134/s1607672907050134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Gvozdev VA, Abramov YA, Kogan GL, Lavrov SA. Distorted heterochromatin replication in Drosophila melanogaster polytene chromosomes as a result of euchromatin-heterochromatin rearrangements. RUSS J GENET+ 2007. [DOI: 10.1134/s1022795407010024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Kolesnikova TD, Andreeva EN, Pindyurin AV, Ananko NG, Belyakin SN, Shloma VV, Yurlova AA, Makunin IV, Pokholkova GV, Volkova EI, Zarutskaya EA, Kokoza EB, Semeshin VF, Belyaeva ES, Zhimulev IF. Contribution of the SuUR gene to the organization of epigenetically repressed regions of Drosophila melanogaster chromosomes. RUSS J GENET+ 2006. [DOI: 10.1134/s1022795406080011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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19
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Biessmann H, Prasad S, Walter MF, Mason JM. Euchromatic and heterochromatic domains at Drosophila telomeres. Biochem Cell Biol 2005; 83:477-85. [PMID: 16094451 DOI: 10.1139/o05-053] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Noncoding repetitive sequences make up a large portion of eukaryotic genomes, but their function is not well understood. Large blocks of repetitive DNA-forming heterochromatin around the centromeres are required for this region to function properly, but are difficult to analyze. The smaller regions of heterochromatin at the telomeres provide an opportunity to study their DNA and protein composition. Drosophila telomere length is maintained through the targeted transposition of specific non-long terminal repeat retrotransposons to chromosome ends, where they form long tandem arrays. A subterminal telomere-associated sequence (TAS) lies immediately proximal to the terminal-retrotransposon array. Here, we review the experimental support for the heterochromatic features of Drosophila telomeres, and provide evidence that telomeric regions contain 2 distinct chromatin subdomains: TAS, which exhibits features that resemble beta heterochromatin; and the terminal array of retrotransposons, which appears euchromatic. This organization is significantly different from the telomeric organization of other eukaryotes, where the terminal telomerase-generated repeats are often folded in a t-loop structure and become part of the heterochromatin protein complex.
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Affiliation(s)
- Harald Biessmann
- Developmental Biology Center, University of California, Irvine, CA 92697, USA.
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20
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Wallace JA, Orr-Weaver TL. Replication of heterochromatin: insights into mechanisms of epigenetic inheritance. Chromosoma 2005; 114:389-402. [PMID: 16220346 DOI: 10.1007/s00412-005-0024-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Revised: 08/13/2005] [Accepted: 08/15/2005] [Indexed: 12/20/2022]
Abstract
Heterochromatin is composed of tightly condensed chromatin in which the histones are deacetylated and methylated, and specific nonhistone proteins are bound. Additionally, in vertebrates and plants, the DNA within heterochromatin is methylated. As the heterochromatic state is stably inherited, replication of heterochromatin requires not only duplication of the DNA but also a reinstallment of the appropriate protein and DNA modifications. Thus replication of heterochromatin provides a framework for understanding mechanisms of epigenetic inheritance. In recent studies, roles have been identified for replication factors in reinstating heterochromatin, particularly functions for origin recognition complex, proliferating cell nuclear antigen, and chromatin-assembly factor 1 in recruiting the heterochromatin binding protein HP1, a histone methyltransferase, a DNA methyltransferase, and a chromatin remodeling complex. Potential mechanistic links between these factors are discussed. In some cells, replication of the heterochromatin is blocked, and in Drosophila this inhibition is mediated by a chromatin binding protein SuUR.
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21
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Andreyeva EN, Belyaeva ES, Semeshin VF, Pokholkova GV, Zhimulev IF. Three distinct chromatin domains in telomere ends of polytene chromosomes in Drosophila melanogaster Tel mutants. J Cell Sci 2005; 118:5465-77. [PMID: 16278293 DOI: 10.1242/jcs.02654] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Drosophila melanogaster telomeric DNA is known to comprise two domains: the terminal tract of retrotransposons (HeT-A, TART and TAHRE) and telomere-associated sequences (TAS). Chromosome tips are capped by a protein complex, which is assembled on the chromosome ends independently of the underlying terminal DNA sequences. To investigate the properties of these domains in salivary gland polytene chromosomes, we made use of Tel mutants. Telomeres in this background are elongated owing to the amplification of a block of terminal retroelements. Supercompact heterochromatin is absent from the telomeres of polytene chromosomes: electron microscopy analysis identifies the telomeric cap and the tract of retroelements as a reticular material, having no discernible banding pattern, whereas TAS repeats appear as faint bands. According to the pattern of bound proteins, the cap, tract of retroelements and TAS constitute distinct and non-overlapping domains in telomeres. SUUR, HP2, SU(VAR)3-7 and H3Me3K27 localize to the cap region, as has been demonstrated for HP1. All these proteins are also found in pericentric heterochromatin. The tract of retroelements is associated with proteins characteristic for both heterochromatin (H3Me3K9) and euchromatin (H3Me3K4, JIL-1, Z4). The TAS region is enriched for H3Me3K27. PC and E(Z) are detected both in TAS and many intercalary heterochromatin regions. Telomeres complete replication earlier than heterochromatic regions. The frequency of telomeric associations in salivary gland polytene chromosomes does not depend on the SuUR gene dosage, rather it appears to be defined by the telomere length.
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Affiliation(s)
- Evgenia N Andreyeva
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Novosibirsk, 630090, Russia
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22
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Kolesnikova TD, Makunin IV, Volkova EI, Pirrotta V, Belyaeva ES, Zhimulev IF. Functional dissection of the Suppressor of UnderReplication protein of Drosophila melanogaster: identification of domains influencing chromosome binding and DNA replication. Genetica 2005; 124:187-200. [PMID: 16134332 DOI: 10.1007/s10709-005-1167-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The Suppressor of UnderReplication (SuUR) gene controls the DNA underreplication in intercalary and pericentric heterochromatin of Drosophila melanogaster salivary gland polytene chromosomes. In the present work, we investigate the functional importance of different regions of the SUUR protein by expressing truncations of the protein in an UAS-GAL4 system. We find that SUUR has at least two separate chromosome-binding regions that are able to recognize intercalary and pericentric heterochromatin specifically. The C-terminal part controls DNA underreplication in intercalary heterochromatin and partially in pericentric heterochromatin regions. The C-terminal half of SUUR suppresses endoreplication when ectopically expressed in the salivary gland. Ectopic expression of the N-terminal fragments of SUUR depletes endogenous SUUR from polytene chromosomes, causes the SuUR- phenotype and induces specific swellings in heterochromatin.
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Affiliation(s)
- T D Kolesnikova
- Laboratory of Molecular Cytogenetics, Institute of Cytology and Genetics SB RAS, Lavrentyev Ave. 10, 630090 Novosibirsk, Russia
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23
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Abstract
We focus here on the intercalary heterochromatin (IH) of Drosophila melanogaster and, in particular, its molecular properties. In the polytene chromosomes of Drosophila, IH is represented by a reproducible set of dense bands scattered along the euchromatic arms. IH contains mainly unique DNA sequences, and shares certain features with other heterochromatin types such as pericentric, telomeric, and PEV-induced heterochromatin, the inactive mammalian X-chromosome and the heterochromatized male chromosome set in coccids. These features are transcriptional silencing, chromatin compactness, late DNA replication, underrreplication or elimination in somatic cells, and formation of the heterochromatin state in early embryogenesis. Post-translational modification of histones and the specific nonhistone protein complexes are shown to participate in the establishment and maintenance of silencing for all heterochromatin types. Many IH regions contain binding sites for HP1 and/or Pc-G proteins and all the regions are sites of heterochromatin-associated SuUR protein. Some IH regions are known to contain homeotic genes. Summarizing these data, we suggest that IH regions comprise stable inactivated genes, whose silencing is developmentally programmed.
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Affiliation(s)
- Igor F Zhimulev
- Institute of Cytology and Genetics, Siberian Division of Russian Academy of Sciences, Russia
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24
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Zhimulev IF, Belyaeva ES, Semeshin VF, Koryakov DE, Demakov SA, Demakova OV, Pokholkova GV, Andreyeva EN. Polytene Chromosomes: 70 Years of Genetic Research. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 241:203-75. [PMID: 15548421 DOI: 10.1016/s0074-7696(04)41004-3] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Polytene chromosomes were described in 1881 and since 1934 they have served as an outstanding model for a variety of genetic experiments. Using the polytene chromosomes, numerous biological phenomena were discovered. First the polytene chromosomes served as a model of the interphase chromosomes in general. In polytene chromosomes, condensed (bands), decondensed (interbands), genetically active (puffs), and silent (pericentric and intercalary heterochromatin as well as regions subject to position effect variegation) regions were found and their features were described in detail. Analysis of the general organization of replication and transcription at the cytological level has become possible using polytene chromosomes. In studies of sequential puff formation it was found for the first time that the steroid hormone (ecdysone) exerts its action through gene activation, and that the process of gene activation upon ecdysone proceeds as a cascade. Namely on the polytene chromosomes a new phenomenon of cellular stress response (heat shock) was discovered. Subsequently chromatin boundaries (insulators) were discovered to flank the heat shock puffs. Major progress in solving the problems of dosage compensation and position effect variegation phenomena was mainly related to studies on polytene chromosomes. This review summarizes the current status of studies of polytene chromosomes and of various phenomena described using this successful model.
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Affiliation(s)
- I F Zhimulev
- Institute of Cytology and Genetics, Russian Academy of Sciences, Novosibirsk, 630090, Russia
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25
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Volkova EI, Yurlova AA, Kolesnikova TD, Makunin IV, Zhimulev IF. Ectopic expression of the Suppressor of Underreplication gene inhibits endocycles but not the mitotic cell cycle in Drosophila melanogaster. Mol Genet Genomics 2003; 270:387-93. [PMID: 14508681 DOI: 10.1007/s00438-003-0924-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2003] [Accepted: 08/25/2003] [Indexed: 10/26/2022]
Abstract
The Suppressor of Underreplication ( SuUR) gene contributes to the regulation of DNA replication in regions of intercalary heterochromatin in salivary gland polytene chromosomes. In the SuUR mutant these regions complete replication earlier than in wild type and, as a consequence, undergo full polytenization. Here we describe the effects of ectopic expression of SuUR using the GAL4-UAS system. We demonstrate that ectopically expressed SuUR exerts qualitatively distinct influences on polyploid and diploid tissues. Ectopic expression of SuUR inhibits DNA replication in polytene salivary gland nuclei, and reduces the degree of amplification of chorion protein genes that occurs in the follicle cell lineage. Effects caused by ectopic SuUR in diploid tissues vary considerably; there is no obvious effect on eye formation, but apoptosis is observed in the wing disc, and wing shape is distorted. The effect of ectopic SuUR expression is enhanced by mutations in the genes E2F and mus209 ( PCNA). Differential responses of polyploid and diploid cells to ectopic SuUR may reflect differences in the mechanisms underlying mitotic cell cycles and endocycles.
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Affiliation(s)
- E I Volkova
- Institute of Cytology and Genetics, Siberian Division of Russian Academy of Sciences, 10 Lavrentyev Ave., 630090 Novosibirsk, Russia
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