1
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Melnikova LS, Molodina VV, Georgiev PG, Golovnin AK. Role of Mod(mdg4)-67.2 Protein in Interactions between Su(Hw)-Dependent Complexes and Their Recruitment to Chromatin. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:626-636. [PMID: 38831500 DOI: 10.1134/s0006297924040035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/23/2023] [Accepted: 10/24/2023] [Indexed: 06/05/2024]
Abstract
Su(Hw) belongs to the class of proteins that organize chromosome architecture, determine promoter activity, and participate in formation of the boundaries/insulators between the regulatory domains. This protein contains a cluster of 12 zinc fingers of the C2H2 type, some of which are responsible for binding to the consensus site. The Su(Hw) protein forms complex with the Mod(mdg4)-67.2 and the CP190 proteins, where the last one binds to all known Drosophila insulators. To further study functioning of the Su(Hw)-dependent complexes, we used the previously described su(Hw)E8 mutation with inactive seventh zinc finger, which produces mutant protein that cannot bind to the consensus site. The present work shows that the Su(Hw)E8 protein continues to directly interact with the CP190 and Mod(mdg4)-67.2 proteins. Through interaction with Mod(mdg4)-67.2, the Su(Hw)E8 protein can be recruited into the Su(Hw)-dependent complexes formed on chromatin and enhance their insulator activity. Our results demonstrate that the Su(Hw) dependent complexes without bound DNA can be recruited to the Su(Hw) binding sites through the specific protein-protein interactions that are stabilized by Mod(mdg4)-67.2.
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Affiliation(s)
- Larisa S Melnikova
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia.
| | - Varvara V Molodina
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
| | - Pavel G Georgiev
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
| | - Anton K Golovnin
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
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2
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Bag I, Chen Y, D'Orazio K, Lopez P, Wenzel S, Takagi Y, Lei EP. Isha is a su(Hw) mRNA-binding protein required for gypsy insulator function. G3 (BETHESDA, MD.) 2022; 12:jkac152. [PMID: 35708663 PMCID: PMC9434307 DOI: 10.1093/g3journal/jkac152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
Chromatin insulators are DNA-protein complexes localized throughout the genome capable of establishing independent transcriptional domains. It was previously reported that the Drosophila su(Hw) mRNA physically associates with the gypsy chromatin insulator protein complex within the nucleus and may serve a noncoding function to affect insulator activity. However, how this mRNA is recruited to the gypsy complex is not known. Here, we utilized RNA-affinity pulldown coupled with mass spectrometry to identify a novel RNA-binding protein, Isha (CG4266), that associates with su(Hw) mRNA in vitro and in vivo. Isha harbors a conserved RNA recognition motif and RNA Polymerase II C-terminal domain-interacting domain (CID). We found that Isha physically interacts with total and elongating Polymerase II and associates with chromatin at the 5' end of genes in an RNA-dependent manner. Furthermore, ChIP-seq analysis reveals Isha overlaps particularly with the core gypsy insulator component CP190 on chromatin. Depletion of Isha reduces enhancer-blocking and barrier activities of the gypsy insulator and disrupts the nuclear localization of insulator bodies. Our results reveal a novel factor Isha that promotes gypsy insulator activity that may act as a nuclear RNA-binding protein adapter for su(Hw) noncoding mRNA.
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Affiliation(s)
- Indira Bag
- Nuclear Organization and Gene Expression Section, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yang Chen
- Nuclear Organization and Gene Expression Section, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Karole D'Orazio
- Nuclear Organization and Gene Expression Section, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Prisma Lopez
- Nuclear Organization and Gene Expression Section, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sabine Wenzel
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Yuichiro Takagi
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Elissa P Lei
- Corresponding author: Nuclear Organization and Gene Expression Section, Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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3
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M1BP cooperates with CP190 to activate transcription at TAD borders and promote chromatin insulator activity. Nat Commun 2021; 12:4170. [PMID: 34234130 PMCID: PMC8263732 DOI: 10.1038/s41467-021-24407-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 06/09/2021] [Indexed: 11/10/2022] Open
Abstract
Genome organization is driven by forces affecting transcriptional state, but the relationship between transcription and genome architecture remains unclear. Here, we identified the Drosophila transcription factor Motif 1 Binding Protein (M1BP) in physical association with the gypsy chromatin insulator core complex, including the universal insulator protein CP190. M1BP is required for enhancer-blocking and barrier activities of the gypsy insulator as well as its proper nuclear localization. Genome-wide, M1BP specifically colocalizes with CP190 at Motif 1-containing promoters, which are enriched at topologically associating domain (TAD) borders. M1BP facilitates CP190 chromatin binding at many shared sites and vice versa. Both factors promote Motif 1-dependent gene expression and transcription near TAD borders genome-wide. Finally, loss of M1BP reduces chromatin accessibility and increases both inter- and intra-TAD local genome compaction. Our results reveal physical and functional interaction between CP190 and M1BP to activate transcription at TAD borders and mediate chromatin insulator-dependent genome organization. Transcriptional state plays a role in genome organization, however factors that link these processes are not well known. Here, the authors show Drosophila transcription factor Motif 1-binding protein (M1BP) interacts with the insulator protein CP190 to promote insulator function and activate Motif 1-dependent transcription at topologically associating domain (TAD) borders.
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4
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Melnikova LS, Georgiev PG, Golovnin AK. The Functions and Mechanisms of Action of Insulators in the Genomes of Higher Eukaryotes. Acta Naturae 2020; 12:15-33. [PMID: 33456975 PMCID: PMC7800606 DOI: 10.32607/actanaturae.11144] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 10/12/2020] [Indexed: 12/22/2022] Open
Abstract
The mechanisms underlying long-range interactions between chromatin regions and the principles of chromosomal architecture formation are currently under extensive scrutiny. A special class of regulatory elements known as insulators is believed to be involved in the regulation of specific long-range interactions between enhancers and promoters. This review focuses on the insulators of Drosophila and mammals, and it also briefly characterizes the proteins responsible for their functional activity. It was initially believed that the main properties of insulators are blocking of enhancers and the formation of independent transcription domains. We present experimental data proving that the chromatin loops formed by insulators play only an auxiliary role in enhancer blocking. The review also discusses the mechanisms involved in the formation of topologically associating domains and their role in the formation of the chromosomal architecture and regulation of gene transcription.
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Affiliation(s)
- L. S. Melnikova
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia
| | - P. G. Georgiev
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia
| | - A. K. Golovnin
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia
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5
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Hollmann NM, Jagtap PKA, Masiewicz P, Guitart T, Simon B, Provaznik J, Stein F, Haberkant P, Sweetapple LJ, Villacorta L, Mooijman D, Benes V, Savitski MM, Gebauer F, Hennig J. Pseudo-RNA-Binding Domains Mediate RNA Structure Specificity in Upstream of N-Ras. Cell Rep 2020; 32:107930. [PMID: 32697992 PMCID: PMC7383231 DOI: 10.1016/j.celrep.2020.107930] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/03/2020] [Accepted: 06/29/2020] [Indexed: 12/12/2022] Open
Abstract
RNA-binding proteins (RBPs) commonly feature multiple RNA-binding domains (RBDs), which provide these proteins with a modular architecture. Accumulating evidence supports that RBP architectural modularity and adaptability define the specificity of their interactions with RNA. However, how multiple RBDs recognize their cognate single-stranded RNA (ssRNA) sequences in concert remains poorly understood. Here, we use Upstream of N-Ras (Unr) as a model system to address this question. Although reported to contain five ssRNA-binding cold-shock domains (CSDs), we demonstrate that Unr includes an additional four CSDs that do not bind RNA (pseudo-RBDs) but are involved in mediating RNA tertiary structure specificity by reducing the conformational heterogeneity of Unr. Disrupting the interactions between canonical and non-canonical CSDs impacts RNA binding, Unr-mediated translation regulation, and the Unr-dependent RNA interactome. Taken together, our studies reveal a new paradigm in protein-RNA recognition, where interactions between RBDs and pseudo-RBDs select RNA tertiary structures, influence RNP assembly, and define target specificity.
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Affiliation(s)
- Nele Merret Hollmann
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany; Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | | | - Pawel Masiewicz
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Tanit Guitart
- Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - Bernd Simon
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Jan Provaznik
- Genomics Core Facility, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Frank Stein
- Proteomics Core Facility, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Per Haberkant
- Proteomics Core Facility, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Lara Jayne Sweetapple
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Laura Villacorta
- Genomics Core Facility, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Dylan Mooijman
- Developmental Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Vladimir Benes
- Genomics Core Facility, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Mikhail M Savitski
- Proteomics Core Facility, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany; Genome Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Fátima Gebauer
- Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
| | - Janosch Hennig
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany.
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The Role of Insulation in Patterning Gene Expression. Genes (Basel) 2019; 10:genes10100767. [PMID: 31569427 PMCID: PMC6827083 DOI: 10.3390/genes10100767] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 09/19/2019] [Accepted: 09/24/2019] [Indexed: 12/16/2022] Open
Abstract
Development is orchestrated by regulatory elements that turn genes ON or OFF in precise spatial and temporal patterns. Many safety mechanisms prevent inappropriate action of a regulatory element on the wrong gene promoter. In flies and mammals, dedicated DNA elements (insulators) recruit protein factors (insulator binding proteins, or IBPs) to shield promoters from regulatory elements. In mammals, a single IBP called CCCTC-binding factor (CTCF) is known, whereas genetic and biochemical analyses in Drosophila have identified a larger repertoire of IBPs. How insulators function at the molecular level is not fully understood, but it is currently thought that they fold chromosomes into conformations that affect regulatory element-promoter communication. Here, we review the discovery of insulators and describe their properties. We discuss recent genetic studies in flies and mice to address the question: Is gene insulation important for animal development? Comparing and contrasting observations in these two species reveal that they have different requirements for insulation, but that insulation is a conserved and critical gene regulation strategy.
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7
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The same domain of Su(Hw) is required for enhancer blocking and direct promoter repression. Sci Rep 2019; 9:5314. [PMID: 30926937 PMCID: PMC6441048 DOI: 10.1038/s41598-019-41761-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/14/2019] [Indexed: 12/22/2022] Open
Abstract
Suppressor of Hairy-wing [Su(Hw)] is a DNA-binding architectural protein that participates in the organization of insulators and repression of promoters in Drosophila. This protein contains acidic regions at both ends and a central cluster of 12 zinc finger domains, some of which are involved in the specific recognition of the binding site. One of the well-described in vivo function of Su(Hw) is the repression of transcription of neuronal genes in oocytes. Here, we have found that the same Su(Hw) C-terminal region (aa 720–892) is required for insulation as well as for promoter repression. The best characterized partners of Su(Hw), CP190 and Mod(mdg4)-67.2, are not involved in the repression of neuronal genes. Taken together, these results suggest that an unknown protein or protein complex binds to the C-terminal region of Su(Hw) and is responsible for the direct repression activity of Su(Hw).
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8
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Bag I, Dale RK, Palmer C, Lei EP. The zinc-finger protein CLAMP promotes gypsy chromatin insulator function in Drosophila. J Cell Sci 2019; 132:jcs.226092. [PMID: 30718365 DOI: 10.1242/jcs.226092] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 01/28/2019] [Indexed: 01/31/2023] Open
Abstract
Chromatin insulators are DNA-protein complexes that establish independent higher-order DNA domains to influence transcription. Insulators are functionally defined by two properties: they can block communication between an enhancer and a promoter, and also act as a barrier between heterochromatin and euchromatin. In Drosophila, the gypsy insulator complex contains three core components; Su(Hw), CP190 and Mod(mdg4)67.2. Here, we identify a novel role for Chromatin-linked adaptor for MSL proteins (CLAMP) in promoting gypsy chromatin insulator function. When clamp is knocked down, gypsy-dependent enhancer-blocking and barrier activities are strongly reduced. CLAMP associates physically with the core gypsy insulator complex, and ChIP-seq analysis reveals extensive overlap, particularly with promoter-bound CP190 on chromatin. Depletion of CLAMP disrupts CP190 binding at a minority of shared sites, whereas depletion of CP190 results in extensive loss of CLAMP chromatin association. Finally, reduction of CLAMP disrupts CP190 localization within the nucleus. Our results support a positive functional relationship between CLAMP and CP190 to promote gypsy chromatin insulator activity.
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Affiliation(s)
- Indira Bag
- Nuclear Organization and Gene Expression Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.,Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ryan K Dale
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cameron Palmer
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Elissa P Lei
- Nuclear Organization and Gene Expression Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA .,Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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9
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Shep RNA-Binding Capacity Is Required for Antagonism of gypsy Chromatin Insulator Activity. G3-GENES GENOMES GENETICS 2019; 9:749-754. [PMID: 30630880 PMCID: PMC6404607 DOI: 10.1534/g3.118.200923] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Chromatin insulators are DNA-protein complexes that regulate chromatin structure and gene expression in a wide range of organisms. These complexes also harbor enhancer blocking and barrier activities. Increasing evidence suggests that RNA molecules are integral components of insulator complexes. However, how these RNA molecules are involved in insulator function remains unclear. The Drosophila RNA-binding protein Shep associates with the gypsy insulator complex and inhibits insulator activities. By mutating key residues in the RRM domains, we generated a Shep mutant protein incapable of RNA-binding, and this mutant lost the ability to inhibit barrier activity. In addition, we found that one of many wildtype Shep isoforms but not RRM mutant Shep was sufficient to repress enhancer blocking activities. Finally, wildtype Shep rescued synthetic lethality of shep, mod(mdg4) double-mutants and developmental defects of shep mutant neurons, whereas mutant Shep failed to do so. These results indicate that the RNA-binding ability of Shep is essential for its ability to antagonize insulator activities and promote neuronal maturation. Our findings suggest that regulation of insulator function by RNA-binding proteins relies on RNA-mediated interactions.
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10
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Glenn SE, Geyer PK. Investigation of the Developmental Requirements of Drosophila HP1 and Insulator Protein Partner, HIPP1. G3 (BETHESDA, MD.) 2019; 9:345-357. [PMID: 30514714 PMCID: PMC6385973 DOI: 10.1534/g3.118.200705] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 11/30/2018] [Indexed: 12/02/2022]
Abstract
Drosophila Suppressor of Hairy-wing [Su(Hw)] is a multifunctional zinc finger DNA binding protein. Transcriptional regulation by Su(Hw) is essential in the ovary and testis, where Su(Hw) functions primarily as a repressor. Recently, the HP1a and Insulator Partner Protein 1 (HIPP1) was found to extensively co-localize with Su(Hw) and other insulator binding proteins in euchromatic regions of the genome, and with Heterochromatin Protein 1a (HP1a) in heterochromatic regions. As HIPP1 is the homolog of the human co-repressor Chromodomain Y-Like (CDYL), we tested its requirement in establishing transcriptional repression in flies. To this end, we generated multiple Hipp1 null alleles and a tagged derivative of the endogenous gene (Hipp1GFP ), using CRISPR mutagenesis. We show that HIPP1 is a widely expressed nuclear protein that is dispensable for viability, as well as female and male fertility. We find that HIPP1 and HP1a display minimum co-localization in interphase cells, and HP1a-dependent transcriptional repression of several reporter genes is HIPP1-independent, indicating that HIPP1 is not essential for HP1a-dependent heterochromatin formation. Despite Su(Hw) having a major role in promoting HIPP1 occupancy in euchromatin, we show that HIPP1 is dispensable for the transcriptional and insulator functions of Su(Hw), indicating that HIPP1 is not a critical Su(Hw) cofactor. Further studies are needed to clarify the role of HIPP1 in Drosophila development.
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Affiliation(s)
| | - Pamela K Geyer
- Molecular Medicine Program
- Department of Biochemistry, University of Iowa, Iowa City, IA 52242
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11
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Light induced DNA-functionalized TiO 2 nanocrystalline interface: Theoretical and experimental insights towards DNA damage detection. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 188:159-176. [PMID: 30308399 DOI: 10.1016/j.jphotobiol.2018.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 07/26/2018] [Accepted: 08/03/2018] [Indexed: 11/22/2022]
Abstract
Owing to the emerging applications of DNA-functionalized TiO2 nanocrystals towards DNA damage detection, it is inevitable to understand the better chemistry as well as in-depth molecular interaction phenomena. Fundamentally, energy difference underlies the layer-by-layer construction, resulted in the increase of the interaction energy and thus, altering the electrochemical behavior. Herein, Density functional theory (DFT) calculations were performed using DMol3 and DFTB+ codes successfully to elucidate the structural, electronics, and vibrational properties of the layer-by-layer components composing ss-DNA/dopamine/TiO2/FTO. The obtained results are in good agreement with the experimental findings. The band gaps of FTO and TiO2 were computationally obtained at 3.335 and 3.136 eV which are comparable with the experimental data (3.500 eV; FTO and 3.200 eV; TiO2). Frontier orbital analysis is also considered to elucidate their electron transfer phenomena. Further, a 100 ns MD simulations are carried out using canonical ensemble embedded with COMPASS-Universal Forcefields generating useful thermodynamics parameters. Binding energies indicate increasing interaction energies for the layer-by-layer nanosystem, in agreement with the increasing diameter of electrochemical impedance spectroscopy (EIS) semicircle. Our results reveal the fundamental understanding of the DNA-functionalized TiO2 nanocrystals down to molecular and electronic level and further, paving a way of its application towards nanoelectrochemical DNA biosensors.
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12
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Melnikova L, Kostyuchenko M, Parshikov A, Georgiev P, Golovnin A. Role of Su(Hw) zinc finger 10 and interaction with CP190 and Mod(mdg4) proteins in recruiting the Su(Hw) complex to chromatin sites in Drosophila. PLoS One 2018; 13:e0193497. [PMID: 29474480 PMCID: PMC5825117 DOI: 10.1371/journal.pone.0193497] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 02/12/2018] [Indexed: 02/07/2023] Open
Abstract
Su(Hw) belongs to the class of proteins that organize chromosome architecture and boundaries/insulators between regulatory domains. This protein contains a cluster of 12 zinc finger domains most of which are responsible for binding to three different modules in the consensus site. Su(Hw) forms a complex with CP190 and Mod(mdg4)-67.2 proteins that binds to well-known Drosophila insulators. To understand how Su(Hw) performs its activities and binds to specific sites in chromatin, we have examined the previously described su(Hw)f mutation that disrupts the 10th zinc finger (ZF10) responsible for Su(Hw) binding to the upstream module. The results have shown that Su(Hw)f loses the ability to interact with CP190 in the absence of DNA. In contrast, complete deletion of ZF10 does not prevent the interaction between Su(Hw)Δ10 and CP190. Having studied insulator complex formation in different mutant backgrounds, we conclude that both association with CP190 and Mod(mdg4)-67.2 partners and proper organization of DNA binding site are essential for the efficient recruitment of the Su(Hw) complex to chromatin insulators.
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Affiliation(s)
- Larisa Melnikova
- Department of Drosophila Molecular Genetics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Margarita Kostyuchenko
- Department of Drosophila Molecular Genetics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander Parshikov
- Department of the Control of Genetic Processes, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Pavel Georgiev
- Department of the Control of Genetic Processes, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- * E-mail: (AG); (PG)
| | - Anton Golovnin
- Department of Drosophila Molecular Genetics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- * E-mail: (AG); (PG)
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13
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Johnston WL, Krizus A, Ramani AK, Dunham W, Youn JY, Fraser AG, Gingras AC, Dennis JW. C. elegans SUP-46, an HNRNPM family RNA-binding protein that prevents paternally-mediated epigenetic sterility. BMC Biol 2017; 15:61. [PMID: 28716093 PMCID: PMC5513350 DOI: 10.1186/s12915-017-0398-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/21/2017] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND In addition to DNA, gametes contribute epigenetic information in the form of histones and non-coding RNA. Epigenetic programs often respond to stressful environmental conditions and provide a heritable history of ancestral stress that allows for adaptation and propagation of the species. In the nematode C. elegans, defective epigenetic transmission often manifests as progressive germline mortality. We previously isolated sup-46 in a screen for suppressors of the hexosamine pathway gene mutant, gna-2(qa705). In this study, we examine the role of SUP-46 in stress resistance and progressive germline mortality. RESULTS We identified SUP-46 as an HNRNPM family RNA-binding protein, and uncovered a highly novel role for SUP-46 in preventing paternally-mediated progressive germline mortality following mating. Proximity biotinylation profiling of human homologs (HNRNPM, MYEF2) identified proteins of ribonucleoprotein complexes previously shown to contain non-coding RNA. Like HNRNPM and MYEF2, SUP-46 was associated with multiple RNA granules, including stress granules, and also formed granules on active chromatin. SUP-46 depletion disrupted germ RNA granules and caused ectopic sperm, increased sperm transcripts, and chronic heat stress sensitivity. SUP-46 was also required for resistance to acute heat stress, and a conserved "MYEF2" motif was identified that was needed for stress resistance. CONCLUSIONS In mammals, non-coding RNA from the sperm of stressed males has been shown to recapitulate paternal stress phenotypes in the offspring. Our results suggest that HNRNPM family proteins enable stress resistance and paternally-mediated epigenetic transmission that may be conserved across species.
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Affiliation(s)
- Wendy L. Johnston
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Aldis Krizus
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Arun K. Ramani
- Centre for Computational Medicine, The Hospital for Sick Children, Toronto, ON Canada
| | - Wade Dunham
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Ji Young Youn
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
| | - Andrew G. Fraser
- Department of Molecular Genetics, University of Toronto, Toronto, ON Canada
- The Donnelly Centre, University of Toronto, Toronto, ON Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON Canada
| | - James W. Dennis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON Canada
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14
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Three-Dimensional Genome Organization and Function in Drosophila. Genetics 2017; 205:5-24. [PMID: 28049701 PMCID: PMC5223523 DOI: 10.1534/genetics.115.185132] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 10/15/2016] [Indexed: 12/18/2022] Open
Abstract
Understanding how the metazoan genome is used during development and cell differentiation is one of the major challenges in the postgenomic era. Early studies in Drosophila suggested that three-dimensional (3D) chromosome organization plays important regulatory roles in this process and recent technological advances started to reveal connections at the molecular level. Here we will consider general features of the architectural organization of the Drosophila genome, providing historical perspective and insights from recent work. We will compare the linear and spatial segmentation of the fly genome and focus on the two key regulators of genome architecture: insulator components and Polycomb group proteins. With its unique set of genetic tools and a compact, well annotated genome, Drosophila is poised to remain a model system of choice for rapid progress in understanding principles of genome organization and to serve as a proving ground for development of 3D genome-engineering techniques.
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Dash S, Siddam AD, Barnum CE, Janga SC, Lachke SA. RNA-binding proteins in eye development and disease: implication of conserved RNA granule components. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 7:527-57. [PMID: 27133484 DOI: 10.1002/wrna.1355] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 03/21/2016] [Indexed: 01/16/2023]
Abstract
The molecular biology of metazoan eye development is an area of intense investigation. These efforts have led to the surprising recognition that although insect and vertebrate eyes have dramatically different structures, the orthologs or family members of several conserved transcription and signaling regulators such as Pax6, Six3, Prox1, and Bmp4 are commonly required for their development. In contrast, our understanding of posttranscriptional regulation in eye development and disease, particularly regarding the function of RNA-binding proteins (RBPs), is limited. We examine the present knowledge of RBPs in eye development in the insect model Drosophila as well as several vertebrate models such as fish, frog, chicken, and mouse. Interestingly, of the 42 RBPs that have been investigated for their expression or function in vertebrate eye development, 24 (~60%) are recognized in eukaryotic cells as components of RNA granules such as processing bodies, stress granules, or other specialized ribonucleoprotein (RNP) complexes. We discuss the distinct developmental and cellular events that may necessitate potential RBP/RNA granule-associated RNA regulon models to facilitate posttranscriptional control of gene expression in eye morphogenesis. In support of these hypotheses, three RBPs and RNP/RNA granule components Tdrd7, Caprin2, and Stau2 are linked to ocular developmental defects such as congenital cataract, Peters anomaly, and microphthalmia in human patients or animal models. We conclude by discussing the utility of interdisciplinary approaches such as the bioinformatics tool iSyTE (integrated Systems Tool for Eye gene discovery) to prioritize RBPs for deriving posttranscriptional regulatory networks in eye development and disease. WIREs RNA 2016, 7:527-557. doi: 10.1002/wrna.1355 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Soma Dash
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Archana D Siddam
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Carrie E Barnum
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Sarath Chandra Janga
- Department of Biohealth Informatics, School of Informatics and Computing, Indiana University & Purdue University Indianapolis, Indianapolis, IN, USA.,Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE, USA.,Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, USA
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16
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Abstract
Large quantities of DNA, RNA, proteins and other cellular components are often required for biochemistry and molecular biology experiments. The short life cycle of Drosophila enables collection of large quantities of material from embryos, larvae, pupae and adult flies, in a synchronized way, at a low economic cost. A major strategy for propagating large numbers of flies is the use of a fly population cage. This useful and common tool in the Drososphila community is an efficient way to regularly produce milligrams to tens of grams of embryos, depending on uniformity of developmental stage desired. While a population cage can be time consuming to set up, maintaining a cage over months takes much less time and enables rapid collection of biological material in a short period. This paper describes a detailed and flexible protocol for the maintenance of a Drosophila melanogaster population cage, starting with 1.5 g of harvested material from the previous cycle.
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Affiliation(s)
- Juan Manuel Caravaca
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health
| | - Elissa P Lei
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health;
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17
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Tikhonov M, Gasanov NB, Georgiev P, Maksimenko O. A Model System in S2 Cells to Test the Functional Activities of Drosophila Insulators. Acta Naturae 2015; 7:97-106. [PMID: 26798496 PMCID: PMC4717254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Insulators are a special class of regulatory elements that can regulate interactions between enhancers and promoters in the genome of high eukaryotes. To date, the mechanisms of insulator action remain unknown, which is primarily related to the lack of convenient model systems. We suggested studying a model system which is based on transient expression of a plasmid with an enhancer of the copia transposable element, in Drosophila embryonic cell lines. We demonstrated that during transient transfection of circle plasmids with a well-known Drosophila insulator from the gypsy retrotransposon, the insulator exhibits in an enhancer-blocking assay the same properties as in Drosophila stable transgenic lines. Therefore, the Drosophila cell line is suitable for studying the main activities of insulators, which provides additional opportunities for investigating the functional role of certain insulator proteins.
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Affiliation(s)
- M. Tikhonov
- Institute of Gene Biology Russian Academy of Sciences, Vavilova str., 34/5, 119334, Moscow, Russia
| | - N. B. Gasanov
- Institute of Gene Biology Russian Academy of Sciences, Vavilova str., 34/5, 119334, Moscow, Russia
| | - P. Georgiev
- Institute of Gene Biology Russian Academy of Sciences, Vavilova str., 34/5, 119334, Moscow, Russia
| | - O. Maksimenko
- Institute of Gene Biology Russian Academy of Sciences, Vavilova str., 34/5, 119334, Moscow, Russia
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18
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Restraint of the G2/M transition by the SR/RRM family mRNA shuttling binding protein SNXAHRB1 in Aspergillus nidulans. Genetics 2014; 198:617-33. [PMID: 25104516 DOI: 10.1534/genetics.114.167445] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Control of the eukaryotic G2/M transition by CDC2/CYCLINB is tightly regulated by protein-protein interactions, protein phosphorylations, and nuclear localization of CDC2/CYCLINB. We previously reported a screen, in Aspergillus nidulans, for extragenic suppressors of nimX2(cdc2) that resulted in the identification of the cold-sensitive snxA1 mutation. We demonstrate here that snxA1 suppresses defects in regulators of the CDK1 mitotic induction pathway, including nimX2(cdc) (2), nimE6(cyclinB), and nimT23(cdc) (25), but does not suppress G2-arresting nimA1/nimA5 mutations, the S-arresting nimE10(cyclinB) mutation, or three other G1/S phase mutations. snxA encodes the A. nidulans homolog of Saccharomyces cerevisiae Hrb1/Gbp2; nonessential shuttling messenger RNA (mRNA)-binding proteins belonging to the serine-arginine-rich (SR) and RNA recognition motif (RRM) protein family; and human heterogeneous ribonucleoprotein-M, a spliceosomal component involved in pre-mRNA processing and alternative splicing. snxA(Hrb) (1) is nonessential, its deletion phenocopies the snxA1 mutation, and its overexpression rescues snxA1 and ΔsnxA mutant phenotypes. snxA1 and a second allele isolated in this study, snxA2, are hypomorphic mutations that result from decreased transcript and protein levels, suggesting that snxA acts normally to restrain cell cycle progression. SNXA(HRB1) is predominantly nuclear, but is not retained in the nucleus during the partially closed mitosis of A. nidulans. We show that the snxA1 mutation does not suppress nimX2 by altering NIMX2(CDC2)/NIME(CYCLINB) kinase activity and that snxA1 or ΔsnxA alter localization patterns of NIME(CYCLINB) at the restrictive temperatures for snxA1 and nimX2. Together, these findings suggest a novel and previously unreported role of an SR/RRM family protein in cell cycle regulation, specifically in control of the CDK1 mitotic induction pathway.
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Dale RK, Matzat LH, Lei EP. metaseq: a Python package for integrative genome-wide analysis reveals relationships between chromatin insulators and associated nuclear mRNA. Nucleic Acids Res 2014; 42:9158-70. [PMID: 25063299 DOI: 10.1093/nar/gku644] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Here we introduce metaseq, a software library written in Python, which enables loading multiple genomic data formats into standard Python data structures and allows flexible, customized manipulation and visualization of data from high-throughput sequencing studies. We demonstrate its practical use by analyzing multiple datasets related to chromatin insulators, which are DNA-protein complexes proposed to organize the genome into distinct transcriptional domains. Recent studies in Drosophila and mammals have implicated RNA in the regulation of chromatin insulator activities. Moreover, the Drosophila RNA-binding protein Shep has been shown to antagonize gypsy insulator activity in a tissue-specific manner, but the precise role of RNA in this process remains unclear. Better understanding of chromatin insulator regulation requires integration of multiple datasets, including those from chromatin-binding, RNA-binding, and gene expression experiments. We use metaseq to integrate RIP- and ChIP-seq data for Shep and the core gypsy insulator protein Su(Hw) in two different cell types, along with publicly available ChIP-chip and RNA-seq data. Based on the metaseq-enabled analysis presented here, we propose a model where Shep associates with chromatin cotranscriptionally, then is recruited to insulator complexes in trans where it plays a negative role in insulator activity.
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Affiliation(s)
- Ryan K Dale
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Leah H Matzat
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Elissa P Lei
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
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