1
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Alahmari AA, Chaubey AH, Jonnakuti VS, Tisdale AA, Schwarz CD, Cornwell AC, Maraszek KE, Paterson EJ, Kim M, Venkat S, Gomez EC, Wang J, Gurova KV, Yalamanchili HK, Feigin ME. CPSF3 inhibition blocks pancreatic cancer cell proliferation through disruption of core histone mRNA processing. RNA (NEW YORK, N.Y.) 2024; 30:281-297. [PMID: 38191171 PMCID: PMC10870380 DOI: 10.1261/rna.079931.123] [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: 12/15/2023] [Accepted: 01/02/2024] [Indexed: 01/10/2024]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with limited effective treatment options, potentiating the importance of uncovering novel drug targets. Here, we target cleavage and polyadenylation specificity factor 3 (CPSF3), the 3' endonuclease that catalyzes mRNA cleavage during polyadenylation and histone mRNA processing. We find that CPSF3 is highly expressed in PDAC and is associated with poor prognosis. CPSF3 knockdown blocks PDAC cell proliferation and colony formation in vitro and tumor growth in vivo. Chemical inhibition of CPSF3 by the small molecule JTE-607 also attenuates PDAC cell proliferation and colony formation, while it has no effect on cell proliferation of nontransformed immortalized control pancreatic cells. Mechanistically, JTE-607 induces transcriptional readthrough in replication-dependent histones, reduces core histone expression, destabilizes chromatin structure, and arrests cells in the S-phase of the cell cycle. Therefore, CPSF3 represents a potential therapeutic target for the treatment of PDAC.
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Affiliation(s)
- Abdulrahman A Alahmari
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Alkharj 11942, Saudi Arabia
| | - Aditi H Chaubey
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Venkata S Jonnakuti
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
- Program in Quantitative and Computational Biology, Baylor College of Medicine, Houston, Texas 77030, USA
- Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Arwen A Tisdale
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Carla D Schwarz
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Abigail C Cornwell
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Kathryn E Maraszek
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Emily J Paterson
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Minsuh Kim
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Swati Venkat
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Eduardo Cortes Gomez
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Jianmin Wang
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Katerina V Gurova
- Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
| | - Hari Krishna Yalamanchili
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Michael E Feigin
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, New York 14203, USA
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2
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Mendiratta S, Ray-Gallet D, Lemaire S, Gatto A, Forest A, Kerlin MA, Almouzni G. Regulation of replicative histone RNA metabolism by the histone chaperone ASF1. Mol Cell 2024; 84:791-801.e6. [PMID: 38262410 DOI: 10.1016/j.molcel.2023.12.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 08/18/2023] [Accepted: 12/21/2023] [Indexed: 01/25/2024]
Abstract
In S phase, duplicating and assembling the whole genome into chromatin requires upregulation of replicative histone gene expression. Here, we explored how histone chaperones control histone production in human cells to ensure a proper link with chromatin assembly. Depletion of the ASF1 chaperone specifically decreases the pool of replicative histones both at the protein and RNA levels. The decrease in their overall expression, revealed by total RNA sequencing (RNA-seq), contrasted with the increase in nascent/newly synthesized RNAs observed by 4sU-labeled RNA-seq. Further inspection of replicative histone RNAs showed a 3' end processing defect with an increase of pre-mRNAs/unprocessed transcripts likely targeted to degradation. Collectively, these data argue for a production defect of replicative histone RNAs in ASF1-depleted cells. We discuss how this regulation of replicative histone RNA metabolism by ASF1 as a "chaperone checkpoint" fine-tunes the histone dosage to avoid unbalanced situations deleterious for cell survival.
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Affiliation(s)
- Shweta Mendiratta
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, Equipe Labellisée Ligue contre le Cancer, 75005 Paris, France
| | - Dominique Ray-Gallet
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, Equipe Labellisée Ligue contre le Cancer, 75005 Paris, France
| | - Sébastien Lemaire
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, Equipe Labellisée Ligue contre le Cancer, 75005 Paris, France
| | - Alberto Gatto
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, Equipe Labellisée Ligue contre le Cancer, 75005 Paris, France
| | - Audrey Forest
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, Equipe Labellisée Ligue contre le Cancer, 75005 Paris, France
| | - Maciej A Kerlin
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, 75005 Paris, France; Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005 Paris, France
| | - Geneviève Almouzni
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, Equipe Labellisée Ligue contre le Cancer, 75005 Paris, France.
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3
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Li W, Jiang C, Zhang E. Advances in the phase separation-organized membraneless organelles in cells: a narrative review. Transl Cancer Res 2022; 10:4929-4946. [PMID: 35116344 PMCID: PMC8797891 DOI: 10.21037/tcr-21-1111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 10/29/2021] [Indexed: 11/26/2022]
Abstract
Membraneless organelles (MLOs) are micro-compartments that lack delimiting membranes, concentrating several macro-molecules with a high local concentration in eukaryotic cells. Recent studies have shown that MLOs have pivotal roles in multiple biological processes, including gene transcription, RNA metabolism, translation, protein modification, and signal transduction. These biological processes in cells have essential functions in many diseases, such as cancer, neurodegenerative diseases, and virus-related diseases. The liquid-liquid phase separation (LLPS) microenvironment within cells is thought to be the driving force for initiating the formation of micro-compartments with a liquid-like property, becoming an important organizing principle for MLOs to mediate organism responses. In this review, we comprehensively elucidated the formation of these MLOs and the relationship between biological functions and associated diseases. The mechanisms underlying the influence of protein concentration and valency on phase separation in cells are also discussed. MLOs undergoing the LLPS process have diverse functions, including stimulation of some adaptive and reversible responses to alter the transcriptional or translational processes, regulation of the concentrations of biomolecules in living cells, and maintenance of cell morphogenesis. Finally, we highlight that the development of this field could pave the way for developing novel therapeutic strategies for the treatment of LLPS-related diseases based on the understanding of phase separation in the coming years.
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Affiliation(s)
- Weihan Li
- Department of Immunology, School of Medicine, Nantong University, Nantong, China
| | - Chenwei Jiang
- Department of Immunology, School of Medicine, Nantong University, Nantong, China
| | - Erhao Zhang
- Department of Immunology, School of Medicine, Nantong University, Nantong, China.,Laboratory of Medical Science, School of Medicine, Nantong University, Nantong, China
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4
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U7 deciphered: the mechanism that forms the unusual 3' end of metazoan replication-dependent histone mRNAs. Biochem Soc Trans 2021; 49:2229-2240. [PMID: 34351387 DOI: 10.1042/bst20210323] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 11/17/2022]
Abstract
In animal cells, replication-dependent histone mRNAs end with a highly conserved stem-loop structure followed by a 4- to 5-nucleotide single-stranded tail. This unique 3' end distinguishes replication-dependent histone mRNAs from all other eukaryotic mRNAs, which end with a poly(A) tail produced by the canonical 3'-end processing mechanism of cleavage and polyadenylation. The pioneering studies of Max Birnstiel's group demonstrated nearly 40 years ago that the unique 3' end of animal replication-dependent histone mRNAs is generated by a distinct processing mechanism, whereby histone mRNA precursors are cleaved downstream of the stem-loop, but this cleavage is not followed by polyadenylation. The key role is played by the U7 snRNP, a complex of a ∼60 nucleotide U7 snRNA and many proteins. Some of these proteins, including the enzymatic component CPSF73, are shared with the canonical cleavage and polyadenylation machinery, justifying the view that the two metazoan pre-mRNA 3'-end processing mechanisms have a common evolutionary origin. The studies on U7 snRNP culminated in the recent breakthrough of reconstituting an entirely recombinant human machinery that is capable of accurately cleaving histone pre-mRNAs, and determining its structure in complex with a pre-mRNA substrate (with 13 proteins and two RNAs) that is poised for the cleavage reaction. The structure uncovered an unanticipated network of interactions within the U7 snRNP and a remarkable mechanism of activating catalytically dormant CPSF73 for the cleavage. This work provides a conceptual framework for understanding other eukaryotic 3'-end processing machineries.
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5
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Potter-Birriel JM, Gonsalvez GB, Marzluff WF. A region of SLBP outside the mRNA-processing domain is essential for deposition of histone mRNA into the Drosophila egg. J Cell Sci 2021; 134:jcs251728. [PMID: 33408246 PMCID: PMC7888719 DOI: 10.1242/jcs.251728] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 12/21/2020] [Indexed: 01/01/2023] Open
Abstract
Replication-dependent histone mRNAs are the only cellular mRNAs that are not polyadenylated, ending in a stemloop instead of a polyA tail, and are normally regulated coordinately with DNA replication. Stemloop-binding protein (SLBP) binds the 3' end of histone mRNA, and is required for processing and translation. During Drosophila oogenesis, large amounts of histone mRNAs and proteins are deposited in the developing oocyte. The maternally deposited histone mRNA is synthesized in stage 10B oocytes after the nurse cells complete endoreduplication. We report that in wild-type stage 10B oocytes, the histone locus bodies (HLBs), formed on the histone genes, produce histone mRNAs in the absence of phosphorylation of Mxc, which is normally required for histone gene expression in S-phase cells. Two mutants of SLBP, one with reduced expression and another with a 10-amino-acid deletion, fail to deposit sufficient histone mRNA in the oocyte, and do not transcribe the histone genes in stage 10B. Mutations in a putative SLBP nuclear localization sequence overlapping the deletion phenocopy the deletion. We conclude that a high concentration of SLBP in the nucleus of stage 10B oocytes is essential for histone gene transcription.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Jennifer Michelle Potter-Birriel
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Interdisciplinary Program in Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Graydon B Gonsalvez
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912 , USA
| | - William F Marzluff
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Interdisciplinary Program in Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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6
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Yang XC, Sun Y, Aik WS, Marzluff WF, Tong L, Dominski Z. Studies with recombinant U7 snRNP demonstrate that CPSF73 is both an endonuclease and a 5'-3' exonuclease. RNA (NEW YORK, N.Y.) 2020; 26:1345-1359. [PMID: 32554553 PMCID: PMC7491329 DOI: 10.1261/rna.076273.120] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 05/26/2020] [Indexed: 05/24/2023]
Abstract
Metazoan replication-dependent histone pre-mRNAs are cleaved at the 3' end by U7 snRNP, an RNA-guided endonuclease that contains U7 snRNA, seven proteins of the Sm ring, FLASH, and four polyadenylation factors: symplekin, CPSF73, CPSF100, and CstF64. A fully recombinant U7 snRNP was recently reconstituted from all 13 components for functional and structural studies and shown to accurately cleave histone pre-mRNAs. Here, we analyzed the activity of recombinant U7 snRNP in more detail. We demonstrate that in addition to cleaving histone pre-mRNAs endonucleolytically, reconstituted U7 snRNP acts as a 5'-3' exonuclease that degrades the downstream product generated from histone pre-mRNAs as a result of the endonucleolytic cleavage. Surprisingly, recombinant U7 snRNP also acts as an endonuclease on single-stranded DNA substrates. All these activities depend on the ability of U7 snRNA to base-pair with the substrate and on the presence of the amino-terminal domain (NTD) of symplekin in either cis or trans, and are abolished by mutations within the catalytic center of CPSF73, or by binding of the NTD to the SSU72 phosphatase of RNA polymerase II. Altogether, our results demonstrate that recombinant U7 snRNP functionally mimics its endogenous counterpart and provide evidence that CPSF73 is both an endonuclease and a 5'-3' exonuclease, consistent with the activity of other members of the β-CASP family. Our results also raise the intriguing possibility that CPSF73 may be involved in some aspects of DNA metabolism in vivo.
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Affiliation(s)
- Xiao-Cui Yang
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Yadong Sun
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Wei Shen Aik
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - William F Marzluff
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Zbigniew Dominski
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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7
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Hur W, Kemp JP, Tarzia M, Deneke VE, Marzluff WF, Duronio RJ, Di Talia S. CDK-Regulated Phase Separation Seeded by Histone Genes Ensures Precise Growth and Function of Histone Locus Bodies. Dev Cell 2020; 54:379-394.e6. [PMID: 32579968 DOI: 10.1016/j.devcel.2020.06.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 02/17/2020] [Accepted: 05/30/2020] [Indexed: 10/24/2022]
Abstract
Many membraneless organelles form through liquid-liquid phase separation, but how their size is controlled and whether size is linked to function remain poorly understood. The histone locus body (HLB) is an evolutionarily conserved nuclear body that regulates the transcription and processing of histone mRNAs. Here, we show that Drosophila HLBs form through phase separation. During embryogenesis, the size of HLBs is controlled in a precise and dynamic manner that is dependent on the cell cycle and zygotic histone gene activation. Control of HLB growth is achieved by a mechanism integrating nascent mRNAs at the histone locus, which facilitates phase separation, and the nuclear concentration of the scaffold protein multi-sex combs (Mxc), which is controlled by the activity of cyclin-dependent kinases. Reduced Cdk2 activity results in smaller HLBs and the appearance of nascent, misprocessed histone mRNAs. Thus, our experiments identify a mechanism linking nuclear body growth and size with gene expression.
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Affiliation(s)
- Woonyung Hur
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27705, USA
| | - James P Kemp
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Marco Tarzia
- LPTMC, CNRS-UMR 7600, Sorbonne Université, 4 Pl. Jussieu, 75005 Paris, France
| | - Victoria E Deneke
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27705, USA
| | - William F Marzluff
- Integrative Program for Biological and Genome Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Robert J Duronio
- Department of Biology, Department of Genetics, Integrative Program for Biological and Genome Sciences, Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Stefano Di Talia
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27705, USA.
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8
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Koreski KP, Rieder LE, McLain LM, Chaubal A, Marzluff WF, Duronio RJ. Drosophila histone locus body assembly and function involves multiple interactions. Mol Biol Cell 2020; 31:1525-1537. [PMID: 32401666 PMCID: PMC7359574 DOI: 10.1091/mbc.e20-03-0176] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The histone locus body (HLB) assembles at replication-dependent (RD) histone loci and concentrates factors required for RD histone mRNA biosynthesis. The Drosophila melanogaster genome has a single locus comprised of ∼100 copies of a tandemly arrayed 5-kB repeat unit containing one copy of each of the 5 RD histone genes. To determine sequence elements required for D. melanogaster HLB formation and histone gene expression, we used transgenic gene arrays containing 12 copies of the histone repeat unit that functionally complement loss of the ∼200 endogenous RD histone genes. A 12x histone gene array in which all H3-H4 promoters were replaced with H2a-H2b promoters (12xPR) does not form an HLB or express high levels of RD histone mRNA in the presence of the endogenous histone genes. In contrast, this same transgenic array is active in HLB assembly and RD histone gene expression in the absence of the endogenous RD histone genes and rescues the lethality caused by homozygous deletion of the RD histone locus. The HLB formed in the absence of endogenous RD histone genes on the mutant 12x array contains all known factors present in the wild-type HLB including CLAMP, which normally binds to GAGA repeats in the H3-H4 promoter. These data suggest that multiple protein–protein and/or protein–DNA interactions contribute to HLB formation, and that the large number of endogenous RD histone gene copies sequester available factor(s) from attenuated transgenic arrays, thereby preventing HLB formation and gene expression on these arrays.
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Affiliation(s)
- Kaitlin P Koreski
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Leila E Rieder
- Department of Biology, Emory University, Atlanta, GA 30322
| | - Lyndsey M McLain
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Ashlesha Chaubal
- Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599
| | - William F Marzluff
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599.,Department of Biology, University of North Carolina, Chapel Hill, NC 27599.,Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599.,Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599.,Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
| | - Robert J Duronio
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599.,Department of Biology, University of North Carolina, Chapel Hill, NC 27599.,Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599.,Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599.,Department of Genetics, University of North Carolina, Chapel Hill, NC 27599
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9
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Bucholc K, Aik WS, Yang XC, Wang K, Zhou ZH, Dadlez M, Marzluff WF, Tong L, Dominski Z. Composition and processing activity of a semi-recombinant holo U7 snRNP. Nucleic Acids Res 2020; 48:1508-1530. [PMID: 31819999 PMCID: PMC7026596 DOI: 10.1093/nar/gkz1148] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 10/29/2019] [Accepted: 11/25/2019] [Indexed: 11/14/2022] Open
Abstract
In animal cells, replication-dependent histone pre-mRNAs are cleaved at the 3' end by U7 snRNP consisting of two core components: a ∼60-nucleotide U7 snRNA and a ring of seven proteins, with Lsm10 and Lsm11 replacing the spliceosomal SmD1 and SmD2. Lsm11 interacts with FLASH and together they recruit the endonuclease CPSF73 and other polyadenylation factors, forming catalytically active holo U7 snRNP. Here, we assembled core U7 snRNP bound to FLASH from recombinant components and analyzed its appearance by electron microscopy and ability to support histone pre-mRNA processing in the presence of polyadenylation factors from nuclear extracts. We demonstrate that semi-recombinant holo U7 snRNP reconstituted in this manner has the same composition and functional properties as endogenous U7 snRNP, and accurately cleaves histone pre-mRNAs in a reconstituted in vitro processing reaction. We also demonstrate that the U7-specific Sm ring assembles efficiently in vitro on a spliceosomal Sm site but the engineered U7 snRNP is functionally impaired. This approach offers a unique opportunity to study the importance of various regions in the Sm proteins and U7 snRNA in 3' end processing of histone pre-mRNAs.
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Affiliation(s)
- Katarzyna Bucholc
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Wei Shen Aik
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Xiao-Cui Yang
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kaituo Wang
- California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Z Hong Zhou
- California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Michał Dadlez
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland.,Institute of Genetics and Biotechnology, Warsaw University, 02-106 Warsaw, Poland
| | - William F Marzluff
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Zbigniew Dominski
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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10
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Albrecht TR, Shevtsov SP, Wu Y, Mascibroda LG, Peart NJ, Huang KL, Sawyer IA, Tong L, Dundr M, Wagner EJ. Integrator subunit 4 is a 'Symplekin-like' scaffold that associates with INTS9/11 to form the Integrator cleavage module. Nucleic Acids Res 2019; 46:4241-4255. [PMID: 29471365 PMCID: PMC5934644 DOI: 10.1093/nar/gky100] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 02/17/2018] [Indexed: 12/14/2022] Open
Abstract
Integrator (INT) is a transcriptional regulatory complex associated with RNA polymerase II that is required for the 3′-end processing of both UsnRNAs and enhancer RNAs. Integrator subunits 9 (INTS9) and INTS11 constitute the catalytic core of INT and are paralogues of the cleavage and polyadenylation specificity factors CPSF100 and CPSF73. While CPSF73/100 are known to associate with a third protein called Symplekin, there is no paralog of Symplekin within INT raising the question of how INTS9/11 associate with the other INT subunits. Here, we have identified that INTS4 is a specific and conserved interaction partner of INTS9/11 that does not interact with either subunit individually. Although INTS4 has no significant homology with Symplekin, it possesses N-terminal HEAT repeats similar to Symplekin but also contains a β-sheet rich C-terminal region, both of which are important to bind INTS9/11. We assess three functions of INT including UsnRNA 3′-end processing, maintenance of Cajal body structural integrity, and formation of histone locus bodies to conclude that INTS4/9/11 are the most critical of the INT subunits for UsnRNA biogenesis. Altogether, these results indicate that INTS4/9/11 compose a heterotrimeric complex that likely represents the Integrator ‘cleavage module’ responsible for its endonucleolytic activity.
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Affiliation(s)
- Todd R Albrecht
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77550, USA
| | - Sergey P Shevtsov
- Department of Cell Biology, Rosalind Franklin University of Medicine and Science, Chicago Medical School, North Chicago, IL 60064, USA
| | - Yixuan Wu
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Lauren G Mascibroda
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77550, USA
| | - Natoya J Peart
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77550, USA
| | - Kai-Lieh Huang
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77550, USA
| | - Iain A Sawyer
- Department of Cell Biology, Rosalind Franklin University of Medicine and Science, Chicago Medical School, North Chicago, IL 60064, USA.,Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Miroslav Dundr
- Department of Cell Biology, Rosalind Franklin University of Medicine and Science, Chicago Medical School, North Chicago, IL 60064, USA
| | - Eric J Wagner
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77550, USA
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11
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Skrajna A, Yang XC, Dadlez M, Marzluff WF, Dominski Z. Protein composition of catalytically active U7-dependent processing complexes assembled on histone pre-mRNA containing biotin and a photo-cleavable linker. Nucleic Acids Res 2019. [PMID: 29529248 PMCID: PMC5961079 DOI: 10.1093/nar/gky133] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
3′ end cleavage of metazoan replication-dependent histone pre-mRNAs requires the multi-subunit holo-U7 snRNP and the stem–loop binding protein (SLBP). The exact composition of the U7 snRNP and details of SLBP function in processing remain unclear. To identify components of the U7 snRNP in an unbiased manner, we developed a novel approach for purifying processing complexes from Drosophila and mouse nuclear extracts. In this method, catalytically active processing complexes are assembled in vitro on a cleavage-resistant histone pre-mRNA containing biotin and a photo-sensitive linker, and eluted from streptavidin beads by UV irradiation for direct analysis by mass spectrometry. In the purified processing complexes, Drosophila and mouse U7 snRNP have a remarkably similar composition, always being associated with CPSF73, CPSF100, symplekin and CstF64. Many other proteins previously implicated in the U7-dependent processing are not present. Drosophila U7 snRNP bound to histone pre-mRNA in the absence of SLBP contains the same subset of polyadenylation factors but is catalytically inactive and addition of recombinant SLBP is sufficient to trigger cleavage. This result suggests that Drosophila SLBP promotes a structural rearrangement of the processing complex, resulting in juxtaposition of the CPSF73 endonuclease with the cleavage site in the pre-mRNA substrate.
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Affiliation(s)
- Aleksandra Skrajna
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Xiao-Cui Yang
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Michal Dadlez
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - William F Marzluff
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Zbigniew Dominski
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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12
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O'Sullivan C, Nickerson PEB, Krupke O, Christie J, Chen LL, Mesa-Peres M, Zhu M, Ryan B, Chow RL, Howard PL. ARS2 is required for retinal progenitor cell S-phase progression and Müller glial cell fate specification. Biochem Cell Biol 2019; 98:50-60. [PMID: 30673303 DOI: 10.1139/bcb-2018-0250] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
During a developmental period that extends postnatally in the mouse, proliferating multipotent retinal progenitor cells produce one of 7 major cell types (rod, cone, bipolar, horizontal, amacrine, ganglion, and Müller glial cells) as they exit the cell cycle in consecutive waves. Cell production in the retina is tightly regulated by intrinsic, extrinsic, spatial, and temporal cues, and is coupled to the timing of cell cycle exit. Arsenic-resistance protein 2 (ARS2, also known as SRRT) is a component of the nuclear cap-binding complex involved in RNA Polymerase II transcription, and is required for cell cycle progression. We show that postnatal retinal progenitor cells (RPCs) require ARS2 for proper progression through S phase, and ARS2 disruption leads to early exit from the cell cycle. Furthermore, we observe an increase in the proportion of cells expressing a rod photoreceptor marker, and a loss of Müller glia marker expression, indicating a role for ARS2 in regulating cell fate specification or differentiation. Knockdown of Flice Associated Huge protein (FLASH), which interacts with ARS2 and is required for cell cycle progression and 3'-end processing of replication-dependent histone transcripts, phenocopies ARS2 knockdown. These data implicate ARS2-FLASH-mediated histone mRNA processing in regulating RPC cell cycle kinetics and neuroglial cell fate specification during postnatal retinal development.
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Affiliation(s)
- Connor O'Sullivan
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | | | - Oliver Krupke
- Department of Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Jennifer Christie
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Li-Li Chen
- Department of Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Monica Mesa-Peres
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Minyan Zhu
- Department of Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Bridget Ryan
- Department of Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Robert L Chow
- Department of Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Perry L Howard
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 2Y2, Canada
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13
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Pettinati I, Grzechnik P, Ribeiro de Almeida C, Brem J, McDonough MA, Dhir S, Proudfoot NJ, Schofield CJ. Biosynthesis of histone messenger RNA employs a specific 3' end endonuclease. eLife 2018; 7:39865. [PMID: 30507380 PMCID: PMC6303110 DOI: 10.7554/elife.39865] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/30/2018] [Indexed: 12/12/2022] Open
Abstract
Replication-dependent (RD) core histone mRNA produced during S-phase is the only known metazoan protein-coding mRNA presenting a 3' stem-loop instead of the otherwise universal polyA tail. A metallo β-lactamase (MBL) fold enzyme, cleavage and polyadenylation specificity factor 73 (CPSF73), is proposed to be the sole endonuclease responsible for 3' end processing of both mRNA classes. We report cellular, genetic, biochemical, substrate selectivity, and crystallographic studies providing evidence that an additional endoribonuclease, MBL domain containing protein 1 (MBLAC1), is selective for 3' processing of RD histone pre-mRNA during the S-phase of the cell cycle. Depletion of MBLAC1 in cells significantly affects cell cycle progression thus identifying MBLAC1 as a new type of S-phase-specific cancer target.
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Affiliation(s)
- Ilaria Pettinati
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Pawel Grzechnik
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | | | - Jurgen Brem
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | | | - Somdutta Dhir
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Nick J Proudfoot
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
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14
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Mendiratta S, Gatto A, Almouzni G. Histone supply: Multitiered regulation ensures chromatin dynamics throughout the cell cycle. J Cell Biol 2018; 218:39-54. [PMID: 30257851 PMCID: PMC6314538 DOI: 10.1083/jcb.201807179] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 09/05/2018] [Accepted: 09/12/2018] [Indexed: 12/14/2022] Open
Abstract
Mendiratta et al. review the interplay between the different regulatory layers that affect the transcription and dynamics of distinct histone H3 variants along the cell cycle. As the building blocks of chromatin, histones are central to establish and maintain particular chromatin states associated with given cell fates. Importantly, histones exist as distinct variants whose expression and incorporation into chromatin are tightly regulated during the cell cycle. During S phase, specialized replicative histone variants ensure the bulk of the chromatinization of the duplicating genome. Other non-replicative histone variants deposited throughout the cell cycle at specific loci use pathways uncoupled from DNA synthesis. Here, we review the particular dynamics of expression, cellular transit, assembly, and disassembly of replicative and non-replicative forms of the histone H3. Beyond the role of histone variants in chromatin dynamics, we review our current knowledge concerning their distinct regulation to control their expression at different levels including transcription, posttranscriptional processing, and protein stability. In light of this unique regulation, we highlight situations where perturbations in histone balance may lead to cellular dysfunction and pathologies.
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Affiliation(s)
- Shweta Mendiratta
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR3664, Equipe Labellisée Ligue contre le Cancer, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie Paris 06, Centre National de la Recherche Scientifique, UMR3664, Paris, France
| | - Alberto Gatto
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR3664, Equipe Labellisée Ligue contre le Cancer, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie Paris 06, Centre National de la Recherche Scientifique, UMR3664, Paris, France
| | - Genevieve Almouzni
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR3664, Equipe Labellisée Ligue contre le Cancer, Paris, France .,Sorbonne Universités, Université Pierre et Marie Curie Paris 06, Centre National de la Recherche Scientifique, UMR3664, Paris, France
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15
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Aik WS, Lin MH, Tan D, Tripathy A, Marzluff WF, Dominski Z, Chou CY, Tong L. The N-terminal domains of FLASH and Lsm11 form a 2:1 heterotrimer for histone pre-mRNA 3'-end processing. PLoS One 2017; 12:e0186034. [PMID: 29020104 PMCID: PMC5636114 DOI: 10.1371/journal.pone.0186034] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 09/23/2017] [Indexed: 11/18/2022] Open
Abstract
Unlike canonical pre-mRNAs, animal replication-dependent histone pre-mRNAs lack introns and are processed at the 3'-end by a mechanism distinct from cleavage and polyadenylation. They have a 3' stem loop and histone downstream element (HDE) that are recognized by stem-loop binding protein (SLBP) and U7 snRNP, respectively. The N-terminal domain (NTD) of Lsm11, a component of U7 snRNP, interacts with FLASH NTD and these two proteins recruit the histone cleavage complex containing the CPSF-73 endonuclease for the cleavage reaction. Here, we determined crystal structures of FLASH NTD and found that it forms a coiled-coil dimer. Using solution light scattering, we characterized the stoichiometry of the FLASH NTD-Lsm11 NTD complex and found that it is a 2:1 heterotrimer, which is supported by observations from analytical ultracentrifugation and crosslinking.
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Affiliation(s)
- Wei Shen Aik
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - Min-Han Lin
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Dazhi Tan
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - Ashutosh Tripathy
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - William F. Marzluff
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Zbigniew Dominski
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Chi-Yuan Chou
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
- * E-mail:
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16
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Routh A, Ji P, Jaworski E, Xia Z, Li W, Wagner EJ. Poly(A)-ClickSeq: click-chemistry for next-generation 3΄-end sequencing without RNA enrichment or fragmentation. Nucleic Acids Res 2017; 45:e112. [PMID: 28449108 PMCID: PMC5499544 DOI: 10.1093/nar/gkx286] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 04/12/2017] [Indexed: 12/20/2022] Open
Abstract
The recent emergence of alternative polyadenylation (APA) as an engine driving transcriptomic diversity has stimulated the development of sequencing methodologies designed to assess genome-wide polyadenylation events. The goal of these approaches is to enrich, partition, capture and ultimately sequence poly(A) site junctions. However, these methods often require poly(A) enrichment, 3΄ linker ligation steps, and RNA fragmentation, which can necessitate higher levels of starting RNA, increase experimental error and potentially introduce bias. We recently reported a click-chemistry based method for generating RNAseq libraries called ‘ClickSeq’. Here, we adapt this method to direct the cDNA synthesis specifically toward the 3΄UTR/poly(A) tail junction of cellular RNA. With this novel approach, we demonstrate sensitive and specific enrichment for poly(A) site junctions without the need for complex sample preparation, fragmentation or purification. Poly(A)-ClickSeq (PAC-seq) is therefore a simple procedure that generates high-quality RNA-seq poly(A) libraries. As a proof-of-principle, we utilized PAC-seq to explore the poly(A) landscape of both human and Drosophila cells in culture and observed outstanding overlap with existing poly(A) databases and also identified previously unannotated poly(A) sites. Moreover, we utilize PAC-seq to quantify and analyze APA events regulated by CFIm25 illustrating how this technology can be harnessed to identify alternatively polyadenylated RNA.
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Affiliation(s)
- Andrew Routh
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA.,Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Ping Ji
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA
| | - Elizabeth Jaworski
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA
| | - Zheng Xia
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA.,Department of Molecular and Cellular Biology, Baylor College of Medicine, TX 77030, USA
| | - Wei Li
- Department of Molecular and Cellular Biology, Baylor College of Medicine, TX 77030, USA
| | - Eric J Wagner
- Department of Biochemistry and Molecular Biology, The University of Texas, Medical Branch, Galveston, TX 77555, USA.,Sealy Center for Structural Biology and Molecular Biophysics, The University of Texas Medical Branch, Galveston, TX 77555, USA
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17
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Genome-Wide RNAi Screens for RNA Processing Events in Drosophila melanogaster S2 Cells. Methods Mol Biol 2017. [PMID: 28766301 DOI: 10.1007/978-1-4939-7204-3_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Over the past 10 years, the design and application of genome-wide screening (GWS) has improved to the point that it can now be done at level of the individual laboratory. The advantages of GWSs compared to classical genetic screens include: immediate identification of a positive scoring gene, relatively short period of time necessary to conduct the screen (as little as 1 week), cell lines do not present developmental needs for gene expression that an organism normally would, and validation/confirmation of results is straightforward. Here, we describe a general protocol for GWS to be conducted in Drosophila melanogaster S2 cells. We provide specific details on what type of experiments must be done before initiating a screen, the materials that are required to conduct a screen, and make suggestions on methods to carry out secondary screening and counter-screening once the initial GWS is complete. Multiple considerations are also raised that focus on how to anticipate false positives/negatives and how to minimize their occurrence through intelligent design. Finally, we provide specific examples of data that our group has gathered from published genome-wide screens in order to exemplify how "hits" are scored and confirmed.
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18
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Duronio RJ, Marzluff WF. Coordinating cell cycle-regulated histone gene expression through assembly and function of the Histone Locus Body. RNA Biol 2017; 14:726-738. [PMID: 28059623 DOI: 10.1080/15476286.2016.1265198] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Metazoan replication-dependent (RD) histone genes encode the only known cellular mRNAs that are not polyadenylated. These mRNAs end instead in a conserved stem-loop, which is formed by an endonucleolytic cleavage of the pre-mRNA. The genes for all 5 histone proteins are clustered in all metazoans and coordinately regulated with high levels of expression during S phase. Production of histone mRNAs occurs in a nuclear body called the Histone Locus Body (HLB), a subdomain of the nucleus defined by a concentration of factors necessary for histone gene transcription and pre-mRNA processing. These factors include the scaffolding protein NPAT, essential for histone gene transcription, and FLASH and U7 snRNP, both essential for histone pre-mRNA processing. Histone gene expression is activated by Cyclin E/Cdk2-mediated phosphorylation of NPAT at the G1-S transition. The concentration of factors within the HLB couples transcription with pre-mRNA processing, enhancing the efficiency of histone mRNA biosynthesis.
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Affiliation(s)
- Robert J Duronio
- a Department of Biology , University of North Carolina , Chapel Hill , NC , USA.,b Department of Genetics , University of North Carolina , Chapel Hill , NC , USA.,c Integrative Program for Biological and Genome Sciences , University of North Carolina , Chapel Hill , NC , USA.,d Lineberger Comprehensive Cancer Center , University of North Carolina , Chapel Hill , NC , USA
| | - William F Marzluff
- a Department of Biology , University of North Carolina , Chapel Hill , NC , USA.,c Integrative Program for Biological and Genome Sciences , University of North Carolina , Chapel Hill , NC , USA.,d Lineberger Comprehensive Cancer Center , University of North Carolina , Chapel Hill , NC , USA.,e Department of Biochemistry and Biophysics , University of North Carolina , Chapel Hill , NC , USA
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19
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Tatomer DC, Terzo E, Curry KP, Salzler H, Sabath I, Zapotoczny G, McKay DJ, Dominski Z, Marzluff WF, Duronio RJ. Concentrating pre-mRNA processing factors in the histone locus body facilitates efficient histone mRNA biogenesis. J Cell Biol 2016; 213:557-70. [PMID: 27241916 PMCID: PMC4896052 DOI: 10.1083/jcb.201504043] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 04/27/2016] [Indexed: 11/22/2022] Open
Abstract
The histone locus body (HLB) assembles at replication-dependent histone genes and concentrates factors required for histone messenger RNA (mRNA) biosynthesis. FLASH (Flice-associated huge protein) and U7 small nuclear RNP (snRNP) are HLB components that participate in 3' processing of the nonpolyadenylated histone mRNAs by recruiting the endonuclease CPSF-73 to histone pre-mRNA. Using transgenes to complement a FLASH mutant, we show that distinct domains of FLASH involved in U7 snRNP binding, histone pre-mRNA cleavage, and HLB localization are all required for proper FLASH function in vivo. By genetically manipulating HLB composition using mutations in FLASH, mutations in the HLB assembly factor Mxc, or depletion of the variant histone H2aV, we find that failure to concentrate FLASH and/or U7 snRNP in the HLB impairs histone pre-mRNA processing. This failure results in accumulation of small amounts of polyadenylated histone mRNA and nascent read-through transcripts at the histone locus. Thus, the HLB concentrates FLASH and U7 snRNP, promoting efficient histone mRNA biosynthesis and coupling 3' end processing with transcription termination.
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Affiliation(s)
- Deirdre C Tatomer
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Esteban Terzo
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Kaitlin P Curry
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Harmony Salzler
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Ivan Sabath
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Grzegorz Zapotoczny
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Daniel J McKay
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599 Department of Genetics, University of North Carolina, Chapel Hill, NC 27599
| | - Zbigniew Dominski
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599
| | - William F Marzluff
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599 Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599 Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599 Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
| | - Robert J Duronio
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599 Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599 Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599 Department of Genetics, University of North Carolina, Chapel Hill, NC 27599
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20
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Ozawa N, Furuhashi H, Masuko K, Numao E, Makino T, Yano T, Kurata S. Organ identity specification factor WGE localizes to the histone locus body and regulates histone expression to ensure genomic stability in Drosophila. Genes Cells 2016; 21:442-56. [PMID: 27145109 DOI: 10.1111/gtc.12354] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/28/2016] [Indexed: 12/19/2022]
Abstract
Over-expression of Winged-Eye (WGE) in the Drosophila eye imaginal disc induces an eye-to-wing transformation. Endogenous WGE is required for organ development, and wge-deficient mutants exhibit growth arrest at the larval stage, suggesting that WGE is critical for normal growth. The function of WGE, however, remains unclear. Here, we analyzed the subcellular localization of WGE to gain insight into its endogenous function. Immunostaining showed that WGE localized to specific nuclear foci called the histone locus body (HLB), an evolutionarily conserved nuclear body required for S phase-specific histone mRNA production. Histone mRNA levels and protein levels in cytosolic fractions were aberrantly up-regulated in wge mutant larva, suggesting a role for WGE in regulating histone gene expression. Genetic analyses showed that wge suppresses position-effect variegation, and that WGE and a HLB component Mute appears to be synergistically involved in heterochromatin formation. Further supporting a role in chromatin regulation, wge-deficient mutants showed derepression of retrotransposons and increased γH2Av signals, a DNA damage marker. These findings suggest that WGE is a component of HLB in Drosophila with a role in heterochromatin formation and transposon silencing. We propose that WGE at HLB contributes to genomic stability and development by regulating heterochromatin structure via histone gene regulation.
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Affiliation(s)
- Nao Ozawa
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Hirofumi Furuhashi
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Keita Masuko
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Eriko Numao
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Takashi Makino
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Tamaki Yano
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Shoichiro Kurata
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
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21
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Skrajna A, Yang XC, Tarnowski K, Fituch K, Marzluff WF, Dominski Z, Dadlez M. Mapping the Interaction Network of Key Proteins Involved in Histone mRNA Generation: A Hydrogen/Deuterium Exchange Study. J Mol Biol 2016; 428:1180-1196. [PMID: 26860583 DOI: 10.1016/j.jmb.2016.01.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 01/27/2016] [Accepted: 01/30/2016] [Indexed: 10/22/2022]
Abstract
Histone pre-mRNAs are cleaved at the 3' end by a complex that contains U7 snRNP, the FLICE-associated huge protein (FLASH) and histone pre-mRNA cleavage complex (HCC) consisting of several polyadenylation factors. Within the complex, the N terminus of FLASH interacts with the N terminus of the U7 snRNP protein Lsm11, and together they recruit the HCC. FLASH through its distant C terminus independently interacts with the C-terminal SANT/Myb-like domain of nuclear protein, ataxia-telangiectasia locus (NPAT), a transcriptional co-activator required for expression of histone genes in S phase. To gain structural information on these interactions, we used mass spectrometry to monitor hydrogen/deuterium exchange in various regions of FLASH, Lsm11 and NPAT alone or in the presence of their respective binding partners. Our results indicate that the FLASH-interacting domain in Lsm11 is highly dynamic, while the more downstream region required for recruiting the HCC exchanges deuterium slowly and likely folds into a stable structure. In FLASH, a stable structure is adopted by the domain that interacts with Lsm11 and this domain is further stabilized by binding Lsm11. Notably, both hydrogen/deuterium exchange experiments and in vitro binding assays demonstrate that Lsm11, in addition to interacting with the N-terminal region of FLASH, also contacts the C-terminal SANT/Myb-like domain of FLASH, the same region that binds NPAT. However, while NPAT stabilizes this domain, Lsm11 causes its partial relaxation. These competing reactions may play a role in regulating histone gene expression in vivo.
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Affiliation(s)
- Aleksandra Skrajna
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland; Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Xiao-Cui Yang
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Krzysztof Tarnowski
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Kinga Fituch
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - William F Marzluff
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Zbigniew Dominski
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Michał Dadlez
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland.
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22
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Tatomer DC, Rizzardi LF, Curry KP, Witkowski AM, Marzluff WF, Duronio RJ. Drosophila Symplekin localizes dynamically to the histone locus body and tricellular junctions. Nucleus 2015; 5:613-25. [PMID: 25493544 DOI: 10.4161/19491034.2014.990860] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The scaffolding protein Symplekin is part of multiple complexes involved in generating and modifying the 3' end of mRNAs, including cleavage-polyadenylation, histone pre-mRNA processing and cytoplasmic polyadenylation. To study these functions in vivo, we examined the localization of Symplekin during development and generated mutations of the Drosophila Symplekin gene. Mutations in Symplekin that reduce Symplekin protein levels alter the efficiency of both poly A(+) and histone mRNA 3' end formation resulting in lethality or sterility. Histone mRNA synthesis takes place at the histone locus body (HLB) and requires a complex composed of Symplekin and several polyadenylation factors that associates with the U7 snRNP. Symplekin is present in the HLB in the early embryo when Cyclin E/Cdk2 is active and histone genes are expressed and is absent from the HLB in cells that have exited the cell cycle. During oogenesis, Symplekin is preferentially localized to HLBs during S-phase in endoreduplicating follicle cells when histone mRNA is synthesized. After the completion of endoreplication, Symplekin accumulates in the cytoplasm, in addition to the nucleoplasm, and localizes to tricellular junctions of the follicle cell epithelium. This localization depends on the RNA binding protein ypsilon schachtel. CPSF-73 and a number of mRNAs are localized at this same site, suggesting that Symplekin participates in cytoplasmic polyadenylation at tricellular junctions.
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Key Words
- CTD, RNA polymerase II C-terminal domain
- Drosophila
- HCC, histone cleavage complex
- HDE, histone downstream element
- HLB, histone locus body
- Madm, MLF1-adaptor molecule
- PAP, poly (A) polymerase
- PAS, poly A signal
- RNA processing, Symplekin
- Rp49, ribosomal protein L32
- SL, stem loop
- SLBP, stem loop binding protein
- Sym, Symplekin
- cas, castor
- gene expression
- histone mRNA
- nuclear bodies
- sop, ribosomal protein S2
- yps, ypsilon schachtel
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Affiliation(s)
- Deirdre C Tatomer
- a Department of Biology ; University of North Carolina ; Chapel Hill , NC USA
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Histone H1: Lessons from Drosophila. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2015; 1859:526-32. [PMID: 26361208 DOI: 10.1016/j.bbagrm.2015.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/28/2015] [Accepted: 09/02/2015] [Indexed: 01/02/2023]
Abstract
Eukaryotic genomes are structured in the form of chromatin with the help of a set of five small basic proteins, the histones. Four of them are highly conserved through evolution, form the basic unit of the chromatin, the nucleosome, and have been intensively studied and are well characterized. The fifth histone, histone H1, adds to this basic structure through its interaction at the entry/exit site of DNA in the nucleosome and makes an essential contribution to the higher order folding of the chromatin fiber. Histone H1 is the less conserved histone and the less known of them. Though for long time considered as a general repressor of gene expression, recent studies in Drosophila have rejected this view and have contributed to uncover important functions on genome stability and development. Here we present some of the most recent data obtained in the Drosophila model system and discuss how the lessons learnt in these studies compare and could be applied to all other eukaryotes.
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Mutagenesis of ARS2 Domains To Assess Possible Roles in Cell Cycle Progression and MicroRNA and Replication-Dependent Histone mRNA Biogenesis. Mol Cell Biol 2015; 35:3753-67. [PMID: 26303529 DOI: 10.1128/mcb.00272-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 08/19/2015] [Indexed: 11/20/2022] Open
Abstract
ARS2 is a regulator of RNA polymerase II transcript processing through its role in the maturation of distinct nuclear cap-binding complex (CBC)-controlled RNA families. In this study, we examined ARS2 domain function in transcript processing. Structural modeling based on the plant ARS2 orthologue, SERRATE, revealed 2 previously uncharacterized domains in mammalian ARS2: an N-terminal domain of unknown function (DUF3546), which is also present in SERRATE, and an RNA recognition motif (RRM) that is present in metazoan ARS2 but not in plants. Both the DUF3546 and zinc finger domain (ZnF) were required for association with microRNA and replication-dependent histone mRNA. Mutations in the ZnF disrupted interaction with FLASH, a key component in histone pre-mRNA processing. Mutations targeting the Mid domain implicated it in DROSHA interaction and microRNA biogenesis. The unstructured C terminus was required for interaction with the CBC protein CBP20, while the RRM was required for cell cycle progression and for binding to FLASH. Together, our results support a bridging model in which ARS2 plays a central role in RNA recognition and processing through multiple protein and RNA interactions.
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25
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Michalski D, Steiniger M. In vivo characterization of the Drosophila mRNA 3' end processing core cleavage complex. RNA (NEW YORK, N.Y.) 2015; 21:1404-18. [PMID: 26081560 PMCID: PMC4509931 DOI: 10.1261/rna.049551.115] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 04/15/2015] [Indexed: 05/07/2023]
Abstract
A core cleavage complex (CCC) consisting of CPSF73, CPSF100, and Symplekin is required for cotranscriptional 3' end processing of all metazoan pre-mRNAs, yet little is known about the in vivo molecular interactions within this complex. The CCC is a component of two distinct complexes, the cleavage/polyadenylation complex and the complex that processes nonpolyadenylated histone pre-mRNAs. RNAi-depletion of CCC factors in Drosophila culture cells causes reduction of CCC processing activity on histone mRNAs, resulting in read through transcription. In contrast, RNAi-depletion of factors only required for histone mRNA processing allows use of downstream cryptic polyadenylation signals to produce polyadenylated histone mRNAs. We used Dmel-2 tissue culture cells stably expressing tagged CCC components to determine that amino acids 272-1080 of Symplekin and the C-terminal approximately 200 amino acids of both CPSF73 and CPSF100 are required for efficient CCC formation in vivo. Additional experiments reveal that the C-terminal 241 amino acids of CPSF100 are sufficient for histone mRNA processing indicating that the first 524 amino acids of CPSF100 are dispensable for both CCC formation and histone mRNA 3' end processing. CCCs containing deletions of Symplekin lacking the first 271 amino acids resulted in dramatic increased use of downstream polyadenylation sites for histone mRNA 3' end processing similar to RNAi-depletion of histone-specific 3' end processing factors FLASH, SLBP, and U7 snRNA. We propose a model in which CCC formation is mediated by CPSF73, CPSF100, and Symplekin C-termini, and the N-terminal region of Symplekin facilitates cotranscriptional 3' end processing of histone mRNAs.
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Affiliation(s)
- Daniel Michalski
- Department of Biology, University of Missouri-St. Louis, St. Louis, Missouri 63121, USA
| | - Mindy Steiniger
- Department of Biology, University of Missouri-St. Louis, St. Louis, Missouri 63121, USA
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26
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Huang Y, Yao X, Wang G. 'Mediator-ing' messenger RNA processing. WILEY INTERDISCIPLINARY REVIEWS-RNA 2014; 6:257-69. [PMID: 25515410 DOI: 10.1002/wrna.1273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 09/29/2014] [Accepted: 10/17/2014] [Indexed: 12/27/2022]
Abstract
Pre-messenger RNA (mRNA) processing, generally including capping, mRNA splicing, and cleavage-polyadenylation, is physically and functionally associated with transcription. The reciprocal coupling between transcription and mRNA processing ensures the efficient and regulated gene expression and editing. Multiple transcription factors/cofactors and mRNA processing factors are involved in the coupling process. This review focuses on several classic examples and recent advances that enlarge our understanding of how the transcriptional factors or cofactors, especially the Mediator complex, contribute to the RNA Pol II elongation, mRNA splicing, and polyadenylation.
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Affiliation(s)
- Yan Huang
- Key Laboratory of Gene Engineering of the Ministry of Education and State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
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27
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Yang XC, Sabath I, Kunduru L, van Wijnen AJ, Marzluff WF, Dominski Z. A conserved interaction that is essential for the biogenesis of histone locus bodies. J Biol Chem 2014; 289:33767-82. [PMID: 25339177 DOI: 10.1074/jbc.m114.616466] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Nuclear protein, ataxia-telangiectasia locus (NPAT) and FLICE-associated huge protein (FLASH) are two major components of discrete nuclear structures called histone locus bodies (HLBs). NPAT is a key co-activator of histone gene transcription, whereas FLASH through its N-terminal region functions in 3' end processing of histone primary transcripts. The C-terminal region of FLASH contains a highly conserved domain that is also present at the end of Yin Yang 1-associated protein-related protein (YARP) and its Drosophila homologue, Mute, previously shown to localize to HLBs in Drosophila cells. Here, we show that the C-terminal domain of human FLASH and YARP interacts with the C-terminal region of NPAT and that this interaction is essential and sufficient to drive FLASH and YARP to HLBs in HeLa cells. Strikingly, only the last 16 amino acids of NPAT are sufficient for the interaction. We also show that the C-terminal domain of Mute interacts with a short region at the end of the Drosophila NPAT orthologue, multi sex combs (Mxc). Altogether, our data indicate that the conserved C-terminal domain shared by FLASH, YARP, and Mute recognizes the C-terminal sequence of NPAT orthologues, thus acting as a signal targeting proteins to HLBs. Finally, we demonstrate that the C-terminal domain of human FLASH can be directly joined with its N-terminal region through alternative splicing. The resulting 190-amino acid MiniFLASH, despite lacking 90% of full-length FLASH, contains all regions necessary for 3' end processing of histone pre-mRNA in vitro and accumulates in HLBs.
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Affiliation(s)
- Xiao-cui Yang
- From the Department of Biochemistry and Biophysics, Integrative Program in Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and
| | - Ivan Sabath
- From the Department of Biochemistry and Biophysics, Integrative Program in Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and
| | - Lalitha Kunduru
- From the Department of Biochemistry and Biophysics, Integrative Program in Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and
| | - Andre J van Wijnen
- the Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905
| | - William F Marzluff
- From the Department of Biochemistry and Biophysics, Integrative Program in Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and
| | - Zbigniew Dominski
- From the Department of Biochemistry and Biophysics, Integrative Program in Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 and
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28
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Molecular mechanisms for the regulation of histone mRNA stem-loop-binding protein by phosphorylation. Proc Natl Acad Sci U S A 2014; 111:E2937-46. [PMID: 25002523 DOI: 10.1073/pnas.1406381111] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Replication-dependent histone mRNAs end with a conserved stem loop that is recognized by stem-loop-binding protein (SLBP). The minimal RNA-processing domain of SLBP is phosphorylated at an internal threonine, and Drosophila SLBP (dSLBP) also is phosphorylated at four serines in its 18-aa C-terminal tail. We show that phosphorylation of dSLBP increases RNA-binding affinity dramatically, and we use structural and biophysical analyses of dSLBP and a crystal structure of human SLBP phosphorylated on the internal threonine to understand the striking improvement in RNA binding. Together these results suggest that, although the C-terminal tail of dSLBP does not contact the RNA, phosphorylation of the tail promotes SLBP conformations competent for RNA binding and thereby appears to reduce the entropic penalty for the association. Increased negative charge in this C-terminal tail balances positively charged residues, allowing a more compact ensemble of structures in the absence of RNA.
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29
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Li Z, Johnson MR, Ke Z, Chen L, Welte MA. Drosophila lipid droplets buffer the H2Av supply to protect early embryonic development. Curr Biol 2014; 24:1485-91. [PMID: 24930966 DOI: 10.1016/j.cub.2014.05.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 03/31/2014] [Accepted: 05/08/2014] [Indexed: 10/25/2022]
Abstract
Assembly of DNA into chromatin requires a delicate balancing act, as both dearth and excess of histones severely disrupt chromatin function [1-3]. In particular, cells need to carefully control histone stoichiometry: if different types of histones are incorporated into chromatin in an imbalanced manner, it can lead to altered gene expression, mitotic errors, and death [4-6]. Both the balance between individual core histones and the balance between core histones and histone variants are critical [5, 7]. Here, we find that in early Drosophila embryos, histone balance in the nuclei is regulated by lipid droplets, cytoplasmic fat-storage organelles [8]. Lipid droplets were previously known to function in long-term histone storage: newly laid embryos contain large amounts of excess histones generated during oogenesis [9], and the maternal supplies of core histone H2A and the histone variant H2Av are anchored to lipid droplets via the novel protein Jabba [3]. We find that in these embryos, synthesis of new H2A and H2Av is imbalanced, and that newly produced H2Av can be recruited to lipid droplets. When droplet sequestration is disrupted by mutating Jabba, embryos display an elevated H2Av/H2A ratio in nuclei as well as mitotic defects, reduced viability, and hypersensitivity to H2Av overexpression. We propose that in Drosophila embryos, lipid droplets serve as a histone buffer, not only storing maternal histones to support the early cell cycles but also transiently sequestering H2Av produced in excess and thus ensuring proper histone balance in the nucleus.
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Affiliation(s)
- Zhihuan Li
- Department of Biology, University of Rochester, Rochester, NY 14627, USA
| | - Matthew R Johnson
- Department of Biology, University of Rochester, Rochester, NY 14627, USA
| | - Zhonghe Ke
- Department of Biology, University of Rochester, Rochester, NY 14627, USA
| | - Lili Chen
- Department of Biology, University of Rochester, Rochester, NY 14627, USA
| | - Michael A Welte
- Department of Biology, University of Rochester, Rochester, NY 14627, USA.
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30
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Messina G, Damia E, Fanti L, Atterrato MT, Celauro E, Mariotti FR, Accardo MC, Walther M, Vernì F, Picchioni D, Moschetti R, Caizzi R, Piacentini L, Cenci G, Giordano E, Dimitri P. Yeti, an essential Drosophila melanogaster gene, encodes a protein required for chromatin organization. J Cell Sci 2014; 127:2577-88. [PMID: 24652835 DOI: 10.1242/jcs.150243] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The evolutionarily conserved family of Bucentaur (BCNT) proteins exhibits a widespread distribution in animal and plants, yet its biological role remains largely unknown. Using Drosophila melanogaster as a model organism, we investigated the in vivo role of the Drosophila BCNT member called YETI. We report that loss of YETI causes lethality before pupation and defects in higher-order chromatin organization, as evidenced by severe impairment in the association of histone H2A.V, nucleosomal histones and epigenetic marks with polytene chromosomes. We also find that YETI binds to polytene chromosomes through its conserved BCNT domain and interacts with the histone variant H2A.V, HP1a and Domino-A (DOM-A), the ATPase subunit of the DOM/Tip60 chromatin remodeling complex. Furthermore, we identify YETI as a downstream target of the Drosophila DOM-A. On the basis of these results, we propose that YETI interacts with H2A.V-exchanging machinery, as a chaperone or as a new subunit of the DOM/Tip60 remodeling complex, and acts to regulate the accumulation of H2A.V at chromatin sites. Overall, our findings suggest an unanticipated role of YETI protein in chromatin organization and provide, for the first time, mechanistic clues on how BCNT proteins control development in multicellular organisms.
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Affiliation(s)
- Giovanni Messina
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
| | - Elisabetta Damia
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
| | - Laura Fanti
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy
| | - Maria Teresa Atterrato
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
| | - Emanuele Celauro
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
| | - Francesca Romana Mariotti
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
| | - Maria Carmela Accardo
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
| | | | - Fiammetta Vernì
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy
| | - Daria Picchioni
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
| | - Roberta Moschetti
- Dipartimento di Biologia, Università degli Studi di Bari, 70121 Bari, Italy
| | - Ruggiero Caizzi
- Dipartimento di Biologia, Università degli Studi di Bari, 70121 Bari, Italy
| | - Lucia Piacentini
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy
| | - Giovanni Cenci
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Sbarro Institute for Cancer Research and Molecular Medicine and Center for Biotechnology, Temple University, Philadelphia, PA 19122, USA
| | - Ennio Giordano
- Dipartimento di Biologia, Università Federico II, 80134 Napoli, Italy
| | - Patrizio Dimitri
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, 00185 Roma, Italy Istituto Pasteur Fondazione Cenci-Bolognetti, Sapienza Università di Roma, 00185 Roma, Italy
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Sabath I, Skrajna A, Yang XC, Dadlez M, Marzluff WF, Dominski Z. 3'-End processing of histone pre-mRNAs in Drosophila: U7 snRNP is associated with FLASH and polyadenylation factors. RNA (NEW YORK, N.Y.) 2013; 19:1726-44. [PMID: 24145821 PMCID: PMC3884669 DOI: 10.1261/rna.040360.113] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
3'-End cleavage of animal replication-dependent histone pre-mRNAs is controlled by the U7 snRNP. Lsm11, the largest component of the U7-specific Sm ring, interacts with FLASH, and in mammalian nuclear extracts these two proteins form a platform that recruits the CPSF73 endonuclease and other polyadenylation factors to the U7 snRNP. FLASH is limiting, and the majority of the U7 snRNP in mammalian extracts exists as a core particle consisting of the U7 snRNA and the Sm ring. Here, we purified the U7 snRNP from Drosophila nuclear extracts and characterized its composition by mass spectrometry. In contrast to the mammalian U7 snRNP, a significant fraction of the Drosophila U7 snRNP contains endogenous FLASH and at least six subunits of the polyadenylation machinery: symplekin, CPSF73, CPSF100, CPSF160, WDR33, and CstF64. The same composite U7 snRNP is recruited to histone pre-mRNA for 3'-end processing. We identified a motif in Drosophila FLASH that is essential for the recruitment of the polyadenylation complex to the U7 snRNP and analyzed the role of other factors, including SLBP and Ars2, in 3'-end processing of Drosophila histone pre-mRNAs. SLBP that binds the upstream stem-loop structure likely recruits a yet-unidentified essential component(s) to the processing machinery. In contrast, Ars2, a protein previously shown to interact with FLASH in mammalian cells, is dispensable for processing in Drosophila. Our studies also demonstrate that Drosophila symplekin and three factors involved in cleavage and polyadenylation-CPSF, CstF, and CF Im-are present in Drosophila nuclear extracts in a stable supercomplex.
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Affiliation(s)
- Ivan Sabath
- Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Aleksandra Skrajna
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 00-901 Warsaw, Poland
| | - Xiao-cui Yang
- Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Michał Dadlez
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 00-901 Warsaw, Poland
- Institute of Genetics and Biotechnology, Warsaw University, 02-106 Warsaw, Poland
| | - William F. Marzluff
- Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Zbigniew Dominski
- Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Corresponding authorE-mail
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Iwaya T, Fukagawa T, Suzuki Y, Takahashi Y, Sawada G, Ishibashi M, Kurashige J, Sudo T, Tanaka F, Shibata K, Endo F, Katagiri H, Ishida K, Kume K, Nishizuka S, Iinuma H, Wakabayashi G, Mori M, Sasako M, Mimori K. Contrasting expression patterns of histone mRNA and microRNA 760 in patients with gastric cancer. Clin Cancer Res 2013; 19:6438-49. [PMID: 24097871 DOI: 10.1158/1078-0432.ccr-12-3186] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
PURPOSE Recent studies revealed that both disseminated tumor cells and noncancerous cells contributed to cancer progression cooperatively in the bone marrow. Here, RNA-seq analysis of bone marrow from gastric cancer patients was performed to identify prognostic markers for gastric cancer. EXPERIMENTAL DESIGN Bone marrow samples from eight gastric cancer patients (stages I and IV: n = 4 each) were used for RNA-seq analysis. Results were validated through quantitative real-time PCR (qRT-PCR) analysis of HIST1H3D expression in 175 bone marrow, 92 peripheral blood, and 115 primary tumor samples from gastric cancer patients. miR-760 expression was assayed using qRT-PCR in 105 bone marrow and 96 primary tumor samples. Luciferase reporter assays were performed to confirm whether histone mRNAs were direct targets of miR-760. miR-760 expression was also evaluated in noncancerous cells from gastric cancer patients. RESULTS RNA-seq analysis of bone marrow samples from gastric cancer patients revealed higher expression of multiple histone mRNAs in stage IV patients. HIST1H3D expression in the bone marrow, peripheral blood, and primary tumor of stage IV patients was higher than that in stage I patients (P = 0.0284, 0.0243, and 0.0006, respectively). In contrast, miR-760 was downregulated in the bone marrow and primary tumor of stage IV patients compared with stage I patients (P = 0.0094 and 0.0018, respectively). Histone mRNA and miR-760 interacted directly. Furthermore, miR-760 was downregulated in noncancerous mucosa in stage IV gastric cancer patients. CONCLUSION Histone mRNA was upregulated, whereas miR-760 was downregulated in the bone marrow and primary tumor of advanced gastric cancer patients, suggesting that the histone mRNA/miR-760 axis had a crucial role in the development of gastric cancer.
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Affiliation(s)
- Takeshi Iwaya
- Authors' Affiliations: Department of Surgery, Kyushu University Beppu Hospital, Beppu; Department of Surgery, Iwate Medical University, Morioka; Department of Gastric Surgery Division, National Cancer Center Hospital; Department of Medical Genome Sciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa-shi, Chiba; Department of Surgery, Teikyo University School of Medicine, Tokyo; Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka, University, Suita; and Department of Digestive Surgery, Hyogo Medical College, Japan
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Salzler HR, Tatomer DC, Malek PY, McDaniel SL, Orlando AN, Marzluff WF, Duronio RJ. A sequence in the Drosophila H3-H4 Promoter triggers histone locus body assembly and biosynthesis of replication-coupled histone mRNAs. Dev Cell 2013; 24:623-34. [PMID: 23537633 DOI: 10.1016/j.devcel.2013.02.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 12/18/2012] [Accepted: 02/22/2013] [Indexed: 01/11/2023]
Abstract
Compartmentalization of RNA biosynthetic factors into nuclear bodies (NBs) is a ubiquitous feature of eukaryotic cells. How NBs initially assemble and ultimately affect gene expression remains unresolved. The histone locus body (HLB) contains factors necessary for replication-coupled histone messenger RNA transcription and processing and associates with histone gene clusters. Using a transgenic assay for ectopic Drosophila HLB assembly, we show that a sequence located between, and transcription from, the divergently transcribed H3-H4 genes nucleates HLB formation and activates other histone genes in the histone gene cluster. In the absence of transcription from the H3-H4 promoter, "proto-HLBs" (containing only a subset of HLB components) form, and the adjacent histone H2a-H2b genes are not expressed. Proto-HLBs also transiently form in mutant embryos with the histone locus deleted. We conclude that HLB assembly occurs through a stepwise process involving stochastic interactions of individual components that localize to a specific sequence in the H3-H4 promoter.
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Affiliation(s)
- Harmony R Salzler
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA
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34
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The variant histone H2A.V of Drosophila--three roles, two guises. Chromosoma 2013; 122:245-58. [PMID: 23553272 DOI: 10.1007/s00412-013-0409-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/19/2013] [Accepted: 03/21/2013] [Indexed: 12/15/2022]
Abstract
Histone variants play important roles in eukaryotic genome organization, the control of gene expression, cell division and DNA repair. Unlike other organisms that employ several H2A variants for different functions, the parsimonious fruit fly Drosophila melanogaster gets along with just a single H2A variant, H2A.V. Remarkably, H2A.V unites within one molecule features and functions of two different mammalian H2A variants, H2A.Z and H2A.X. Accordingly, H2A.V is involved in diverse functions, as an element of a class of active promoter structure, as a foundation for heterochromatin assembly and as a DNA damage sensor. Here, we comprehensively review the current knowledge of this fascinating histone variant.
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35
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Andersen PK, Jensen TH, Lykke-Andersen S. Making ends meet: coordination between RNA 3'-end processing and transcription initiation. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:233-46. [PMID: 23450686 DOI: 10.1002/wrna.1156] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
RNA polymerase II (RNAPII)-mediated gene transcription initiates at promoters and ends at terminators. Transcription termination is intimately connected to 3'-end processing of the produced RNA and already when loaded at the promoter, RNAPII starts to become configured for this downstream event. Conversely, RNAPII is 'reset' as part of the 3'-end processing/termination event, thus preparing the enzyme for its next round of transcription--possibly on the same gene. There is both direct and circumstantial evidence for preferential recycling of RNAPII from the gene terminator back to its own promoter, which supposedly increases the efficiency of the transcription process under conditions where RNAPII levels are rate limiting. Here, we review differences and commonalities between initiation and 3'-end processing/termination processes on various types of RNAPII transcribed genes. In doing so, we discuss the requirements for efficient 3'-end processing/termination and how these may relate to proper recycling of RNAPII.
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Affiliation(s)
- Pia K Andersen
- Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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36
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Dominski Z, Carpousis AJ, Clouet-d'Orval B. Emergence of the β-CASP ribonucleases: highly conserved and ubiquitous metallo-enzymes involved in messenger RNA maturation and degradation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2013; 1829:532-51. [PMID: 23403287 DOI: 10.1016/j.bbagrm.2013.01.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/18/2013] [Accepted: 01/22/2013] [Indexed: 01/05/2023]
Abstract
The β-CASP ribonucleases, which are found in the three domains of life, have in common a core of 460 residues containing seven conserved sequence motifs involved in the tight binding of two catalytic zinc ions. A hallmark of these enzymes is their ability to catalyze both endo- and exo-ribonucleolytic degradation. Exo-ribonucleolytic degradation proceeds in the 5' to 3' direction and is sensitive to the phosphorylation state of the 5' end of a transcript. Recent phylogenomic analyses have shown that the β-CASP ribonucleases can be partitioned into two major subdivisions that correspond to orthologs of eukaryal CPSF73 and bacterial RNase J. We discuss the known functions of the CPSF73 and RNase J orthologs, their association into complexes, and their structure as it relates to mechanism of action. Eukaryal CPSF73 is part of a large multiprotein complex that is involved in the maturation of the 3' end of RNA Polymerase II transcripts and the polyadenylation of messenger RNA. RNase J1 and J2 are paralogs in Bacillus subtilis that are involved in the degradation of messenger RNA and the maturation of non-coding RNA. RNase J1 and J2 co-purify as a heteromeric complex and there is recent evidence that they interact with other enzymes to form a bacterial RNA degradosome. Finally, we speculate on the evolutionary origin of β-CASP ribonucleases and on their functions in Archaea. Orthologs of CPSF73 with endo- and exo-ribonuclease activity are strictly conserved throughout the archaea suggesting a role for these enzymes in the maturation and/or degradation of messenger RNA. This article is part of a Special Issue entitled: RNA Decay mechanisms.
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Affiliation(s)
- Zbigniew Dominski
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, USA
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37
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Chen J, Ezzeddine N, Waltenspiel B, Albrecht TR, Warren WD, Marzluff WF, Wagner EJ. An RNAi screen identifies additional members of the Drosophila Integrator complex and a requirement for cyclin C/Cdk8 in snRNA 3'-end formation. RNA (NEW YORK, N.Y.) 2012; 18:2148-2156. [PMID: 23097424 PMCID: PMC3504667 DOI: 10.1261/rna.035725.112] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 09/17/2012] [Indexed: 06/01/2023]
Abstract
Formation of the 3' end of RNA polymerase II-transcribed snRNAs requires a poorly understood group of proteins called the Integrator complex. Here we used a fluorescence-based read-through reporter that expresses GFP in response to snRNA misprocessing and performed a genome-wide RNAi screen in Drosophila S2 cells to identify novel factors required for snRNA 3'-end formation. In addition to the known Integrator complex members, we identified Asunder and CG4785 as additional Integrator subunits. Functional and biochemical experiments revealed that Asunder and CG4785 are additional core members of the Integrator complex. We also identified a conserved requirement in both fly and human snRNA 3'-end processing for cyclin C and Cdk8 that is distinct from their function in the Mediator Cdk8 module. Moreover, we observed biochemical association between Integrator proteins and cyclin C/Cdk8, and that overexpression of a kinase-dead Cdk8 causes snRNA misprocessing. These data functionally define the Drosophila Integrator complex and demonstrate an additional function for cyclin C/Cdk8 unrelated to its function in Mediator.
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Affiliation(s)
- Jiandong Chen
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, Texas 77030, USA
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas 77030, USA
| | - Nader Ezzeddine
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, Texas 77030, USA
| | - Bernhard Waltenspiel
- Comparative Genomics Centre, School of Pharmacy and Molecular Sciences, James Cook University, Townsville QLD 4811, Queensland, Australia
| | - Todd R. Albrecht
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, Texas 77030, USA
| | - William D. Warren
- Comparative Genomics Centre, School of Pharmacy and Molecular Sciences, James Cook University, Townsville QLD 4811, Queensland, Australia
| | - William F. Marzluff
- Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Eric J. Wagner
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, Texas 77030, USA
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas 77030, USA
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A complex containing the CPSF73 endonuclease and other polyadenylation factors associates with U7 snRNP and is recruited to histone pre-mRNA for 3'-end processing. Mol Cell Biol 2012; 33:28-37. [PMID: 23071092 DOI: 10.1128/mcb.00653-12] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Animal replication-dependent histone pre-mRNAs are processed at the 3' end by endonucleolytic cleavage that is not followed by polyadenylation. The cleavage reaction is catalyzed by CPSF73 and depends on the U7 snRNP and its integral component, Lsm11. A critical role is also played by the 220-kDa protein FLASH, which interacts with Lsm11. Here we demonstrate that the N-terminal regions of these two proteins form a platform that tightly interacts with a unique combination of polyadenylation factors: symplekin, CstF64, and all CPSF subunits, including the endonuclease CPSF73. The interaction is inhibited by alterations in each component of the FLASH/Lsm11 complex, including point mutations in FLASH that are detrimental for processing. The same polyadenylation factors are associated with the endogenous U7 snRNP and are recruited in a U7-dependent manner to histone pre-mRNA. Collectively, our studies identify the molecular mechanism that recruits the CPSF73 endonuclease to histone pre-mRNAs, reveal an unexpected complexity of the U7 snRNP, and suggest that in animal cells polyadenylation factors assemble into two alternative complexes-one specifically crafted to generate polyadenylated mRNAs and the other to generate nonpolyadenylated histone mRNAs that end with the stem-loop.
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39
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Machyna M, Heyn P, Neugebauer KM. Cajal bodies: where form meets function. WILEY INTERDISCIPLINARY REVIEWS-RNA 2012; 4:17-34. [PMID: 23042601 DOI: 10.1002/wrna.1139] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The cell nucleus contains dozens of subcompartments that separate biochemical processes into confined spaces. Cajal bodies (CBs) were discovered more than 100 years ago, but only extensive research in the past decades revealed the surprising complexity of molecular and cellular functions taking place in these structures. Many protein and RNA species are modified and assembled within CBs, which have emerged as a meeting place and factory for ribonucleoprotein (RNP) particles involved in splicing, ribosome biogenesis and telomere maintenance. Recently, a distinct structure near histone gene clusters--the Histone locus body (HLB)--was discovered. Involved in histone mRNA 3'-end formation, HLBs can share several components with CBs. Whether the appearance of distinct HLBs is simply a matter of altered affinity between these structures or of an alternate mode of CB assembly is unknown. However, both structures share basic assembly properties, in which transcription plays a decisive role in initiation. After this seeding event, additional components associate in random order. This appears to be a widespread mechanism for body assembly. CB assembly encompasses an additional layer of complexity, whereby a set of pre-existing substructures can be integrated into mature CBs. We propose this as a multi-seeding model of CB assembly.
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Affiliation(s)
- Martin Machyna
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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40
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Änkö ML, Müller-McNicoll M, Brandl H, Curk T, Gorup C, Henry I, Ule J, Neugebauer KM. The RNA-binding landscapes of two SR proteins reveal unique functions and binding to diverse RNA classes. Genome Biol 2012; 13:R17. [PMID: 22436691 PMCID: PMC3439968 DOI: 10.1186/gb-2012-13-3-r17] [Citation(s) in RCA: 197] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 03/20/2012] [Accepted: 03/21/2012] [Indexed: 01/03/2023] Open
Abstract
Background The SR proteins comprise a family of essential, structurally related RNA binding proteins. The complexity of their RNA targets and specificity of RNA recognition in vivo is not well understood. Here we use iCLIP to globally analyze and compare the RNA binding properties of two SR proteins, SRSF3 and SRSF4, in murine cells. Results SRSF3 and SRSF4 binding sites mapped to largely non-overlapping target genes, and in vivo consensus binding motifs were distinct. Interactions with intronless and intron-containing mRNAs as well as non-coding RNAs were detected. Surprisingly, both SR proteins bound to the 3' ends of the majority of intronless histone transcripts, implicating SRSF3 and SRSF4 in histone mRNA metabolism. In contrast, SRSF3 but not SRSF4 specifically bound transcripts encoding numerous RNA binding proteins. Remarkably, SRSF3 was shown to modulate alternative splicing of its own as well as three other transcripts encoding SR proteins. These SRSF3-mediated splicing events led to downregulation of heterologous SR proteins via nonsense-mediated decay. Conclusions SRSF3 and SRSF4 display unique RNA binding properties underlying diverse cellular regulatory mechanisms, with shared as well as unique coding and non-coding targets. Importantly, CLIP analysis led to the discovery that SRSF3 cross-regulates the expression of other SR protein family members.
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Affiliation(s)
- Minna-Liisa Änkö
- Max Planck Institute of Cell Biology and Genetics, Dresden, Germany.
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41
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Ito S, Fujiyama-Nakamura S, Kimura S, Lim J, Kamoshida Y, Shiozaki-Sato Y, Sawatsubashi S, Suzuki E, Tanabe M, Ueda T, Murata T, Kato H, Ohtake F, Fujiki R, Miki T, Kouzmenko A, Takeyama KI, Kato S. Epigenetic silencing of core histone genes by HERS in Drosophila. Mol Cell 2012; 45:494-504. [PMID: 22365829 DOI: 10.1016/j.molcel.2011.12.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Revised: 09/13/2011] [Accepted: 12/02/2011] [Indexed: 12/23/2022]
Abstract
Cell cycle-dependent expression of canonical histone proteins enables newly synthesized DNA to be integrated into chromatin in replicating cells. However, the molecular basis of cell cycle-dependency in the switching of histone gene regulation remains to be uncovered. Here, we report the identification and biochemical characterization of a molecular switcher, HERS (histone gene-specific epigenetic repressor in late S phase), for nucleosomal core histone gene inactivation in Drosophila. HERS protein is phosphorylated by a cyclin-dependent kinase (Cdk) at the end of S-phase. Phosphorylated HERS binds to histone gene regulatory regions and anchors HP1 and Su(var)3-9 to induce chromatin inactivation through histone H3 lysine 9 methylation. These findings illustrate a salient molecular switch linking epigenetic gene silencing to cell cycle-dependent histone production.
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Affiliation(s)
- Saya Ito
- Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
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42
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snRNA 3' end formation requires heterodimeric association of integrator subunits. Mol Cell Biol 2012; 32:1112-23. [PMID: 22252320 DOI: 10.1128/mcb.06511-11] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The Integrator Complex is a group of proteins responsible for the endonucleolytic cleavage of primary small nuclear RNA (snRNA) transcripts within the nucleus. Integrator subunits 9 and 11 (IntS9/11) are thought to contain the catalytic activity based on their high sequence similarity to CPSF100 and CPSF73, which have been shown to be components of both the poly(A)(+) and histone pre-mRNA cleavage complex. Here we demonstrate that the specific heterodimeric interaction between IntS9 and IntS11 is mediated by a discrete domain present at the extreme C terminus of IntS9 and within the C terminus of IntS11, adjacent to the predicted active site of this endonuclease. This domain is highly conserved within IntS11 but conspicuously absent in CPSF73. Using a cell-based complementation assay that measures Integrator activity, we determined that the IntS9 interaction domain within IntS11 is required for its ability to restore snRNA 3' end processing after RNA interference (RNAi)-mediated depletion of IntS11. Moreover, overexpression of these interaction domains alone elicits snRNA misprocessing through a dominant-negative titration of endogenous Integrator subunits. These data collectively explain the mechanism by which the IntS11/9 and, by analogy, the CPSF73/100 heterodimeric cleavage factors distinguish themselves from each other and demonstrate that the heterodimeric interaction is functionally required for snRNA 3' end formation.
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43
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Chipumuro E, Henriksen MA. The ubiquitin hydrolase USP22 contributes to 3'-end processing of JAK-STAT-inducible genes. FASEB J 2011; 26:842-54. [PMID: 22067483 DOI: 10.1096/fj.11-189498] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The JAK-STAT (Janus kinase-signal transducer and activator of transcription) signaling pathway drives cellular growth, differentiation, and the immune response. STAT-activated gene expression is both rapid and transient and requires dynamic post-translational modification of the chromatin template. We previously showed that monoubiquitination of histone H2B (ubH2B) is highly dynamic at the STAT1 target gene, interferon regulatory factor 1 (IRF1), suggesting that a deubiquitinase is recruited during gene activation. Here, we report that RNAi-mediated knockdown of the ubiquitin hydrolase, USP22, results in 2-fold higher ubH2B, and 2-fold lower transcriptional elongation at IRF1. We also demonstrate that USP22 depletion diminishes 3'-end cleavage/polyadenylation by 2- to 3-fold. Furthermore, the polyadenylation factor CPSF73 is not effectively recruited, and serine 2 phosphorylation (Ser2P) of the C-terminal domain of RNA polymerase II is also disrupted. The transcriptional and processing defects observed in the USP22-knockdown cells are reversed by transient USP22 overexpression. Together, these results suggest that ubH2B helps recruit polyadenylation factors to STAT1-activated genes. We propose a working model, wherein a cycle of H2B ubiquitination/deubiquitination specifies Ser2P to regulate elongation and 3'-end processing of JAK-STAT-inducible mRNAs. These results further elaborate USP22 function and its role as a putative cancer stem cell marker.
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Affiliation(s)
- Edmond Chipumuro
- Department of Biology, The University of Virginia, Charlottesville, VA 22903, USA
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44
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Abstract
Cultured Drosophila melanogaster S2 and S2R+ cell lines have become important tools for uncovering fundamental aspects of cell biology as well as for gene discovery. Despite their utility, these cell lines are nonmotile and cannot build polarized structures or cell-cell contacts. Here we outline a previously isolated, but uncharacterized, Drosophila cell line named Dm-D17-c3 (or D17). These cells spread and migrate in culture, form cell-cell junctions and are susceptible to RNA interference (RNAi). Using this protocol, we describe how investigators, upon receiving cells from the Bloomington stock center, can culture cells and prepare the necessary reagents to plate and image migrating D17 cells; they can then be used to examine intracellular dynamics or observe loss-of-function RNAi phenotypes using an in vitro scratch or wound healing assay. From first thawing frozen ampules of D17 cells, investigators can expect to begin assaying RNAi phenotypes in D17 cells within roughly 2-3 weeks.
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45
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White AE, Burch BD, Yang XC, Gasdaska PY, Dominski Z, Marzluff WF, Duronio RJ. Drosophila histone locus bodies form by hierarchical recruitment of components. ACTA ACUST UNITED AC 2011; 193:677-94. [PMID: 21576393 PMCID: PMC3166876 DOI: 10.1083/jcb.201012077] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
An assembly process involving sequential recruitment of components and hierarchical dependency drives formation of the nuclear structures known as histone locus bodies. Nuclear bodies are protein- and RNA-containing structures that participate in a wide range of processes critical to genome function. Molecular self-organization is thought to drive nuclear body formation, but whether this occurs stochastically or via an ordered, hierarchical process is not fully understood. We addressed this question using RNAi and proteomic approaches in Drosophila melanogaster to identify and characterize novel components of the histone locus body (HLB), a nuclear body involved in the expression of replication-dependent histone genes. We identified the transcription elongation factor suppressor of Ty 6 (Spt6) and a homologue of mammalian nuclear protein of the ataxia telangiectasia–mutated locus that is encoded by the homeotic gene multisex combs (mxc) as novel HLB components. By combining genetic manipulation in both cell culture and embryos with cytological observations of Mxc, Spt6, and the known HLB components, FLICE-associated huge protein, Mute, U7 small nuclear ribonucleoprotein, and MPM-2 phosphoepitope, we demonstrated sequential recruitment and hierarchical dependency for localization of factors to HLBs during development, suggesting that ordered assembly can play a role in nuclear body formation.
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Affiliation(s)
- Anne E White
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
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46
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Burch BD, Godfrey AC, Gasdaska PY, Salzler HR, Duronio RJ, Marzluff WF, Dominski Z. Interaction between FLASH and Lsm11 is essential for histone pre-mRNA processing in vivo in Drosophila. RNA (NEW YORK, N.Y.) 2011; 17:1132-47. [PMID: 21525146 PMCID: PMC3096045 DOI: 10.1261/rna.2566811] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Metazoan replication-dependent histone mRNAs are the only nonpolyadenylated cellular mRNAs. Formation of the histone mRNA 3' end requires the U7 snRNP, which contains Lsm10 and Lsm11, and FLASH, a processing factor that binds Lsm11. Here, we identify sequences in Drosophila FLASH (dFLASH) that bind Drosophila Lsm11 (dLsm11), allow localization of dFLASH to the nucleus and histone locus body (HLB), and participate in histone pre-mRNA processing in vivo. Amino acids 105-154 of dFLASH bind to amino acids 1-78 of dLsm11. A two-amino acid mutation of dLsm11 that prevents dFLASH binding but does not affect localization of U7 snRNP to the HLB cannot rescue the lethality or histone pre-mRNA processing defects resulting from an Lsm11 null mutation. The last 45 amino acids of FLASH are required for efficient localization to the HLB in Drosophila cultured cells. Removing the first 64 amino acids of FLASH has no effect on processing in vivo. Removal of 13 additional amino acids of dFLASH results in a dominant negative protein that binds Lsm11 but inhibits processing of histone pre-mRNA in vivo. Inhibition requires the Lsm11 binding site, suggesting that the mutant dFLASH protein sequesters the U7 snRNP in an inactive complex and that residues between 64 and 77 of dFLASH interact with a factor required for processing. Together, these studies demonstrate that direct interaction between dFLASH and dLsm11 is essential for histone pre-mRNA processing in vivo and for proper development and viability in flies.
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MESH Headings
- Animals
- Binding Sites
- Carrier Proteins/chemistry
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cells, Cultured
- Drosophila/genetics
- Drosophila/metabolism
- Drosophila Proteins/chemistry
- Drosophila Proteins/genetics
- Drosophila Proteins/metabolism
- Histones/genetics
- Histones/metabolism
- RNA Precursors/metabolism
- RNA Processing, Post-Transcriptional
- RNA, Heterogeneous Nuclear/genetics
- RNA, Heterogeneous Nuclear/metabolism
- RNA, Messenger/metabolism
- Ribonucleoprotein, U7 Small Nuclear/genetics
- Ribonucleoprotein, U7 Small Nuclear/metabolism
- Ribonucleoproteins, Small Nuclear/chemistry
- Ribonucleoproteins, Small Nuclear/genetics
- Ribonucleoproteins, Small Nuclear/metabolism
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Affiliation(s)
- Brandon D Burch
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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47
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Shepard PJ, Choi EA, Lu J, Flanagan LA, Hertel KJ, Shi Y. Complex and dynamic landscape of RNA polyadenylation revealed by PAS-Seq. RNA (NEW YORK, N.Y.) 2011; 17:761-72. [PMID: 21343387 PMCID: PMC3062186 DOI: 10.1261/rna.2581711] [Citation(s) in RCA: 331] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 01/11/2011] [Indexed: 05/20/2023]
Abstract
Alternative polyadenylation (APA) of mRNAs has emerged as an important mechanism for post-transcriptional gene regulation in higher eukaryotes. Although microarrays have recently been used to characterize APA globally, they have a number of serious limitations that prevents comprehensive and highly quantitative analysis. To better characterize APA and its regulation, we have developed a deep sequencing-based method called Poly(A) Site Sequencing (PAS-Seq) for quantitatively profiling RNA polyadenylation at the transcriptome level. PAS-Seq not only accurately and comprehensively identifies poly(A) junctions in mRNAs and noncoding RNAs, but also provides quantitative information on the relative abundance of polyadenylated RNAs. PAS-Seq analyses of human and mouse transcriptomes showed that 40%-50% of all expressed genes produce alternatively polyadenylated mRNAs. Furthermore, our study detected evolutionarily conserved polyadenylation of histone mRNAs and revealed novel features of mitochondrial RNA polyadenylation. Finally, PAS-Seq analyses of mouse embryonic stem (ES) cells, neural stem/progenitor (NSP) cells, and neurons not only identified more poly(A) sites than what was found in the entire mouse EST database, but also detected significant changes in the global APA profile that lead to lengthening of 3' untranslated regions (UTR) in many mRNAs during stem cell differentiation. Together, our PAS-Seq analyses revealed a complex landscape of RNA polyadenylation in mammalian cells and the dynamic regulation of APA during stem cell differentiation.
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Affiliation(s)
- Peter J Shepard
- Department of Microbiology and Molecular Genetics, University of California at Irvine, Irvine, California 92697, USA
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48
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Luco RF, Allo M, Schor IE, Kornblihtt AR, Misteli T. Epigenetics in alternative pre-mRNA splicing. Cell 2011; 144:16-26. [PMID: 21215366 DOI: 10.1016/j.cell.2010.11.056] [Citation(s) in RCA: 593] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 09/07/2010] [Accepted: 11/13/2010] [Indexed: 12/11/2022]
Abstract
Alternative splicing plays critical roles in differentiation, development, and disease and is a major source for protein diversity in higher eukaryotes. Analysis of alternative splicing regulation has traditionally focused on RNA sequence elements and their associated splicing factors, but recent provocative studies point to a key function of chromatin structure and histone modifications in alternative splicing regulation. These insights suggest that epigenetic regulation determines not only what parts of the genome are expressed but also how they are spliced.
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Affiliation(s)
- Reini F Luco
- National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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49
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FLASH is required for the endonucleolytic cleavage of histone pre-mRNAs but is dispensable for the 5' exonucleolytic degradation of the downstream cleavage product. Mol Cell Biol 2011; 31:1492-502. [PMID: 21245389 DOI: 10.1128/mcb.00979-10] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
3'-end cleavage of histone pre-mRNAs is catalyzed by CPSF-73 and requires the interaction of two U7 snRNP-associated proteins, FLASH and Lsm11. Here, by using scanning mutagenesis we identify critical residues in human FLASH and Lsm11 that are involved in the interaction between these two proteins. We also demonstrate that mutations in the region of FLASH located between amino acids 50 and 99 do not affect binding of Lsm11. Interestingly, these mutations convert FLASH into an inhibitory protein that reduces in vitro processing efficiency of highly active nuclear extracts. Our results suggest that this region in FLASH in conjunction with Lsm11 is involved in recruiting a yet-unknown processing factor(s) to histone pre-mRNA. Following endonucleolytic cleavage of histone pre-mRNA, the downstream cleavage product (DCP) is degraded by the 5'-3' exonuclease activity of CPSF-73, which also depends on Lsm11. Strikingly, while cleavage of histone pre-mRNA is stimulated by FLASH and inhibited by both dominant negative mutants of FLASH and anti-FLASH antibodies, the 5'-3' degradation of the DCP is not affected. Thus, the recruitment of FLASH to the processing complex plays a critical role in activating the endonuclease mode of CPSF-73 but is dispensable for its 5'-3' exonuclease activity. These results suggest that CPSF-73, the catalytic component in both reactions, can be recruited to histone pre-mRNA largely in a manner independent of FLASH, possibly by a separate domain in Lsm11.
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50
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A subset of Drosophila integrator proteins is essential for efficient U7 snRNA and spliceosomal snRNA 3'-end formation. Mol Cell Biol 2010; 31:328-41. [PMID: 21078872 DOI: 10.1128/mcb.00943-10] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Proper gene expression relies on a class of ubiquitously expressed, uridine-rich small nuclear RNAs (snRNAs) transcribed by RNA polymerase II (RNAPII). Vertebrate snRNAs are transcribed from a unique promoter, which is required for proper 3'-end formation, and cleavage of the nascent transcript involves the activity of a poorly understood set of proteins called the Integrator complex. To examine 3'-end formation in Drosophila melanogaster, we developed a cell-based reporter that monitors aberrant 3'-end formation of snRNA through the gain in expression of green fluorescent protein (GFP). We used this reporter in Drosophila S2 cells to determine requirements for U7 snRNA 3'-end formation and found that processing was strongly dependent upon nucleotides located within the 3' stem-loop as well as sequences likely to comprise the Drosophila equivalent of the vertebrate 3' box. Substitution of the actin promoter for the snRNA promoter abolished proper 3'-end formation, demonstrating the conserved requirement for an snRNA promoter in Drosophila. We tested the requirement for all Drosophila Integrator subunits and found that Integrators 1, 4, 9, and 11 were essential for 3'-end formation and that Integrators 3 and 10 may be dispensable for processing. Depletion of cleavage and polyadenylation factors or of histone pre-mRNA processing factors did not affect U7 snRNA processing efficiency, demonstrating that the Integrator complex does not share components with the mRNA 3'-end processing machinery. Finally, flies harboring mutations in either Integrator 4 or 7 fail to complete development and accumulate significant levels of misprocessed snRNA in the larval stages.
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