1
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Shih M, Zou Y, Ferreira T, Suzuki N, Kim E, Chuang CF, Chang C. The kpc-1 3'UTR facilitates dendritic transport and translation efficiency of mRNAs for dendrite arborization of a mechanosensory neuron important for male courtship. PLoS Genet 2024; 20:e1011362. [PMID: 39110773 PMCID: PMC11333003 DOI: 10.1371/journal.pgen.1011362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 08/19/2024] [Accepted: 07/05/2024] [Indexed: 08/21/2024] Open
Abstract
A recently reported Schizophrenia-associated genetic variant in the 3'UTR of the human furin gene, a homolog of C. elegans kpc-1, highlights an important role of the furin 3'UTR in neuronal development. We isolate three kpc-1 mutants that display abnormal dendrite arborization in PVD neurons and defective male mating behaviors. We show that the kpc-1 3'UTR participates in dendrite branching and self-avoidance. The kpc-1 3'UTR facilitates mRNA localization to branching points and contact points between sibling dendrites and promotes translation efficiency. A predicted secondary structural motif in the kpc-1 3'UTR is required for dendrite self-avoidance. Animals with over-expression of DMA-1, a PVD dendrite receptor, exhibit similar dendrite branching and self-avoidance defects that are suppressed with kpc-1 over-expression. Our results support a model in which KPC-1 proteins are synthesized at branching points and contact points to locally down-regulate DMA-1 receptors to promote dendrite branching and self-avoidance of a mechanosensory neuron important for male courtship.
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Affiliation(s)
- Mushaine Shih
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Yan Zou
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Tarsis Ferreira
- Division of Developmental Biology, Cincinnati Children’s Hospital Research Foundation, Cincinnati, Ohio, United States of America
| | - Nobuko Suzuki
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Eunseo Kim
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Chiou-Fen Chuang
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Chieh Chang
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
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2
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Morales-Polanco F, Lee JH, Barbosa NM, Frydman J. Cotranslational Mechanisms of Protein Biogenesis and Complex Assembly in Eukaryotes. Annu Rev Biomed Data Sci 2022; 5:67-94. [PMID: 35472290 PMCID: PMC11040709 DOI: 10.1146/annurev-biodatasci-121721-095858] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The formation of protein complexes is crucial to most biological functions. The cellular mechanisms governing protein complex biogenesis are not yet well understood, but some principles of cotranslational and posttranslational assembly are beginning to emerge. In bacteria, this process is favored by operons encoding subunits of protein complexes. Eukaryotic cells do not have polycistronic mRNAs, raising the question of how they orchestrate the encounter of unassembled subunits. Here we review the constraints and mechanisms governing eukaryotic co- and posttranslational protein folding and assembly, including the influence of elongation rate on nascent chain targeting, folding, and chaperone interactions. Recent evidence shows that mRNAs encoding subunits of oligomeric assemblies can undergo localized translation and form cytoplasmic condensates that might facilitate the assembly of protein complexes. Understanding the interplay between localized mRNA translation and cotranslational proteostasis will be critical to defining protein complex assembly in vivo.
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Affiliation(s)
| | - Jae Ho Lee
- Department of Biology, Stanford University, Stanford, California, USA;
| | - Natália M Barbosa
- Department of Biology, Stanford University, Stanford, California, USA;
| | - Judith Frydman
- Department of Biology, Stanford University, Stanford, California, USA;
- Department of Genetics, Stanford University, Stanford, California, USA
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3
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Parker DM, Winkenbach LP, Osborne Nishimura E. It’s Just a Phase: Exploring the Relationship Between mRNA, Biomolecular Condensates, and Translational Control. Front Genet 2022; 13:931220. [PMID: 35832192 PMCID: PMC9271857 DOI: 10.3389/fgene.2022.931220] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 06/07/2022] [Indexed: 11/13/2022] Open
Abstract
Cells spatially organize their molecular components to carry out fundamental biological processes and guide proper development. The spatial organization of RNA within the cell can both promote and result from gene expression regulatory control. Recent studies have demonstrated diverse associations between RNA spatial patterning and translation regulatory control. One form of patterning, compartmentalization in biomolecular condensates, has been of particular interest. Generally, transcripts associated with cytoplasmic biomolecular condensates—such as germ granules, stress granules, and P-bodies—are linked with low translational status. However, recent studies have identified new biomolecular condensates with diverse roles associated with active translation. This review outlines RNA compartmentalization in various condensates that occur in association with repressed or active translational states, highlights recent findings in well-studied condensates, and explores novel condensate behaviors.
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Affiliation(s)
- Dylan M. Parker
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States
- Department of Biochemistry, University of Colorado, Boulder, CO, United States
| | - Lindsay P. Winkenbach
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States
| | - Erin Osborne Nishimura
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States
- *Correspondence: Erin Osborne Nishimura,
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4
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Yang TH. An Aggregation Method to Identify the RNA Meta-Stable Secondary Structure and its Functionally Interpretable Structure Ensemble. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2022; 19:75-86. [PMID: 34014829 DOI: 10.1109/tcbb.2021.3082396] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
RNA can provide vital cellular functions through its secondary or tertiary structure. Due to the low-throughput nature of experimental approaches, studies on RNA structures mainly resort to computational methods. However, current existing tools fail to consider RNA structure ensembles and do not provide ways to decipher functional hypotheses for the new predictions. In this research, a novel method was proposed to identify the functionally interpretable structure ensemble of a given RNA sequence and provide the meta-stable structure, or the most frequently observed functional RNA cellular conformation, based on the ensemble. In the prediction of meta-stable structures, the proposed method outperformed existing tools on a yeast test set. The inferred functional aspects were then manually checked and demonstrated a micro-averaging F1 value of 0.92. Further, a biological example of the yeast ASH1-E1 element was discussed to articulate that these functional aspects can also suggest testable hypotheses. Then the proposed method was verified to be well applicable to other species through a human test set. Finally, the proposed method was demonstrated to show resistance to sequence length-dependent performance deterioration.
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5
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Seeking a Role for Translational Control by Alternative Polyadenylation in Saccharomyces cerevisiae. Microorganisms 2021; 9:microorganisms9091885. [PMID: 34576779 PMCID: PMC8464734 DOI: 10.3390/microorganisms9091885] [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: 06/03/2021] [Revised: 08/29/2021] [Accepted: 08/30/2021] [Indexed: 11/17/2022] Open
Abstract
Alternative polyadenylation (APA) represents an important mechanism for regulating isoform-specific translation efficiency, stability, and localisation. Though some progress has been made in understanding its consequences in metazoans, the role of APA in the model organism Saccharomyces cerevisiae remains a relative mystery because, despite abundant studies on the translational state of mRNA, none differentiate mRNA isoforms’ alternative 3′-end. This review discusses the implications of alternative polyadenylation in S. cerevisiae using other organisms to draw inferences. Given the foundational role that research in this yeast has played in the discovery of the mechanisms of cleavage and polyadenylation and in the drivers of APA, it is surprising that such an inference is required. However, because advances in ribosome profiling are insensitive to APA, how it impacts translation is still unclear. To bridge the gap between widespread observed APA and the discovery of any functional consequence, we also provide a review of the experimental techniques used to uncover the functional importance of 3′ UTR isoforms on translation.
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6
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Waldron A, Yajima M. Localized translation on the mitotic apparatus: A history and perspective. Dev Biol 2020; 468:55-58. [PMID: 32979335 DOI: 10.1016/j.ydbio.2020.09.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 09/10/2020] [Accepted: 09/16/2020] [Indexed: 10/23/2022]
Abstract
Localized translation is a proposed biological event that allows mRNA to be translated on site, providing an additional level of protein regulation within a cell. Examples of localized translation have been found or proposed in a variety of cellular contexts from neurons to cancer cells and implicated in both normal development and disease for over a half century. For example, mRNA translation on the mitotic apparatus (MA) was initially hypothesized in the 1950-60s. However, its proof of existence, biological significance and mechanistic details have remained sparse and it is still unclear how well conserved this mechanism may be among different cell types or organisms. In this review, we provide a brief historic summary of translation on the MA and discuss how current and future work may help us understand this biological process that provides a subcellular level of regulation in protein synthesis within a cell.
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Affiliation(s)
- Ashley Waldron
- Department of Molecular Biology Cell Biology Biochemistry, Brown University, 185 Meeting Street, BOX-GL277, Providence, RI 02912, USA
| | - Mamiko Yajima
- Department of Molecular Biology Cell Biology Biochemistry, Brown University, 185 Meeting Street, BOX-GL277, Providence, RI 02912, USA.
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7
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Chaudhuri A, Das S, Das B. Localization elements and zip codes in the intracellular transport and localization of messenger RNAs in Saccharomyces cerevisiae. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 11:e1591. [PMID: 32101377 DOI: 10.1002/wrna.1591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/05/2020] [Accepted: 02/07/2020] [Indexed: 12/13/2022]
Abstract
Intracellular trafficking and localization of mRNAs provide a mechanism of regulation of expression of genes with excellent spatial control. mRNA localization followed by localized translation appears to be a mechanism of targeted protein sorting to a specific cell-compartment, which is linked to the establishment of cell polarity, cell asymmetry, embryonic axis determination, and neuronal plasticity in metazoans. However, the complexity of the mechanism and the components of mRNA localization in higher organisms prompted the use of the unicellular organism Saccharomyces cerevisiae as a simplified model organism to study this vital process. Current knowledge indicates that a variety of mRNAs are asymmetrically and selectively localized to the tip of the bud of the daughter cells, to the vicinity of endoplasmic reticulum, mitochondria, and nucleus in this organism, which are connected to diverse cellular processes. Interestingly, specific cis-acting RNA localization elements (LEs) or RNA zip codes play a crucial role in the localization and trafficking of these localized mRNAs by providing critical binding sites for the specific RNA-binding proteins (RBPs). In this review, we present a comprehensive account of mRNA localization in S. cerevisiae, various types of localization elements influencing the mRNA localization, and the RBPs, which bind to these LEs to implement a number of vital physiological processes. Finally, we emphasize the significance of this process by highlighting their connection to several neuropathological disorders and cancers. This article is categorized under: RNA Export and Localization > RNA Localization.
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Affiliation(s)
- Anusha Chaudhuri
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Subhadeep Das
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Biswadip Das
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
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8
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Desai VP, Frank F, Lee A, Righini M, Lancaster L, Noller HF, Tinoco I, Bustamante C. Co-temporal Force and Fluorescence Measurements Reveal a Ribosomal Gear Shift Mechanism of Translation Regulation by Structured mRNAs. Mol Cell 2019; 75:1007-1019.e5. [PMID: 31471187 DOI: 10.1016/j.molcel.2019.07.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 06/12/2019] [Accepted: 07/15/2019] [Indexed: 11/18/2022]
Abstract
The movement of ribosomes on mRNA is often interrupted by secondary structures that present mechanical barriers and play a central role in translation regulation. We investigate how ribosomes couple their internal conformational changes with the activity of translocation factor EF-G to unwind mRNA secondary structures using high-resolution optical tweezers with single-molecule fluorescence capability. We find that hairpin opening occurs during EF-G-catalyzed translocation and is driven by the forward rotation of the small subunit head. Modulating the magnitude of the hairpin barrier by force shows that ribosomes respond to strong barriers by shifting their operation to an alternative 7-fold-slower kinetic pathway prior to translocation. Shifting into a slow gear results from an allosteric switch in the ribosome that may allow it to exploit thermal fluctuations to overcome mechanical barriers. Finally, we observe that ribosomes occasionally open the hairpin in two successive sub-codon steps, revealing a previously unobserved translocation intermediate.
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Affiliation(s)
- Varsha P Desai
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA; Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Filipp Frank
- Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Antony Lee
- Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Maurizio Righini
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA; Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences, QB3, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Laura Lancaster
- Department of Molecular, Cell, and Developmental Biology and Center for Molecular Biology of RNA, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Harry F Noller
- Department of Molecular, Cell, and Developmental Biology and Center for Molecular Biology of RNA, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Ignacio Tinoco
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Carlos Bustamante
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA; Jason L. Choy Laboratory of Single-Molecule Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biosciences, QB3, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Kavli Energy Nanoscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
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9
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Jung D, Seo JS, Nam J, Kim J. Functional association of Loc1 and Puf6 with RNA helicase Dhh1 in translational regulation of Saccharomyces cerevisiae Ste12. PLoS One 2019; 14:e0220137. [PMID: 31323064 PMCID: PMC6641207 DOI: 10.1371/journal.pone.0220137] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 07/09/2019] [Indexed: 12/14/2022] Open
Abstract
Loc1 and Puf6, which are localized predominantly to the nucleus, are required for the localization and translational repression of the ASH1 mRNA in the yeast, Saccharomyces cerevisiae. During its transport to the daughter cell, the ASH1 mRNA is translationally repressed via associations with She2, Loc1, and Puf6. Here, we investigated the roles of Loc1 and Puf6 in the translation of mRNAs other than that encoding ASH1. In loc1 or puf6 deletion strains, expression of the mating-specific transcription factor, Ste12, was significantly increased at the post-transcriptional level. These phenotypes required the 5’ untranslated region (UTR) of STE12, which carries the putative Puf6-binding sequences. The RNA helicase, Dhh1, which is a known positive regulator for the translation of STE12 mRNA, was found to be functionally connected with Loc1 and Puf6 in the context of Ste12 expression. Our results collectively show that the phosphorylation of the N-terminal Thr16 residue of Dhh1 affects the protein interactions of Dhh1 with Loc1 or Puf6, and consequently regulates Ste12 expression.
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Affiliation(s)
- Daehee Jung
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Jong Seok Seo
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Jayoung Nam
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Jinmi Kim
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
- * E-mail:
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10
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Bioinformatics Approaches to Gain Insights into cis-Regulatory Motifs Involved in mRNA Localization. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1203:165-194. [PMID: 31811635 DOI: 10.1007/978-3-030-31434-7_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Messenger RNA (mRNA) is a fundamental intermediate in the expression of proteins. As an integral part of this important process, protein production can be localized by the targeting of mRNA to a specific subcellular compartment. The subcellular destination of mRNA is suggested to be governed by a region of its primary sequence or secondary structure, which consequently dictates the recruitment of trans-acting factors, such as RNA-binding proteins or regulatory RNAs, to form a messenger ribonucleoprotein particle. This molecular ensemble is requisite for precise and spatiotemporal control of gene expression. In the context of RNA localization, the description of the binding preferences of an RNA-binding protein defines a motif, and one, or more, instance of a given motif is defined as a localization element (zip code). In this chapter, we first discuss the cis-regulatory motifs previously identified as mRNA localization elements. We then describe motif representation in terms of entropy and information content and offer an overview of motif databases and search algorithms. Finally, we provide an outline of the motif topology of asymmetrically localized mRNA molecules.
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11
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Piao M, Sun L, Zhang QC. RNA Regulations and Functions Decoded by Transcriptome-wide RNA Structure Probing. GENOMICS PROTEOMICS & BIOINFORMATICS 2017; 15:267-278. [PMID: 29031843 PMCID: PMC5673676 DOI: 10.1016/j.gpb.2017.05.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 05/09/2017] [Accepted: 05/27/2017] [Indexed: 01/07/2023]
Abstract
RNA folds into intricate structures that are crucial for its functions and regulations. To date, a multitude of approaches for probing structures of the whole transcriptome, i.e., RNA structuromes, have been developed. Applications of these approaches to different cell lines and tissues have generated a rich resource for the study of RNA structure–function relationships at a systems biology level. In this review, we first introduce the designs of these methods and their applications to study different RNA structuromes. We emphasize their technological differences especially their unique advantages and caveats. We then summarize the structural insights in RNA functions and regulations obtained from the studies of RNA structuromes. And finally, we propose potential directions for future improvements and studies.
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Affiliation(s)
- Meiling Piao
- MOE Key Laboratory of Bioinformatics, Beijing Advanced Innovation Center for Structural Biology, Center for Synthetic and Systems Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lei Sun
- MOE Key Laboratory of Bioinformatics, Beijing Advanced Innovation Center for Structural Biology, Center for Synthetic and Systems Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qiangfeng Cliff Zhang
- MOE Key Laboratory of Bioinformatics, Beijing Advanced Innovation Center for Structural Biology, Center for Synthetic and Systems Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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12
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Niessing D, Jansen RP, Pohlmann T, Feldbrügge M. mRNA transport in fungal top models. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 9. [PMID: 28994236 DOI: 10.1002/wrna.1453] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/28/2017] [Accepted: 09/05/2017] [Indexed: 01/13/2023]
Abstract
Eukaryotic cells rely on the precise determination of when and where proteins are synthesized. Spatiotemporal expression is supported by localization of mRNAs to specific subcellular sites and their subsequent local translation. This holds true for somatic cells as well as for oocytes and embryos. Most commonly, mRNA localization is achieved by active transport of the molecules along the actin or microtubule cytoskeleton. Key factors are molecular motors, adaptors, and RNA-binding proteins that recognize defined sequences or structures in cargo mRNAs. A deep understanding of this process has been gained from research on fungal model systems such as Saccharomyces cerevisiae and Ustilago maydis. Recent highlights of these studies are the following: (1) synergistic binding of two RNA-binding proteins is needed for high affinity recognition; (2) RNA sequences undergo profound structural rearrangements upon recognition; (3) mRNA transport is tightly linked to membrane trafficking; (4) mRNAs and ribosomes are transported on the cytoplasmic surface of endosomes; and (5) heteromeric protein complexes are, most likely, assembled co-translationally during endosomal transport. Thus, the study of simple fungal model organisms provides valuable insights into fundamental mechanisms of mRNA transport boosting the understanding of similar events in higher eukaryotes. WIREs RNA 2018, 9:e1453. doi: 10.1002/wrna.1453 This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes RNA Export and Localization > RNA Localization.
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Affiliation(s)
- Dierk Niessing
- Department of Cell Biology, Biomedical Center, Ludwig-Maximilians-University München, Planegg-Martinsried, Germany.,Institute of Structural Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Ralf-Peter Jansen
- Interfaculty Institute of Biochemistry, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Thomas Pohlmann
- Centre of Excellence on Plant Sciences, Institute for Microbiology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Michael Feldbrügge
- Centre of Excellence on Plant Sciences, Institute for Microbiology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
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13
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Scarpin MR, Sigaut L, Temprana SG, Boccaccio GL, Pietrasanta LI, Muschietti JP. Two Arabidopsis late pollen transcripts are detected in cytoplasmic granules. PLANT DIRECT 2017; 1:e00012. [PMID: 31245661 PMCID: PMC6508577 DOI: 10.1002/pld3.12] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 08/11/2017] [Accepted: 08/24/2017] [Indexed: 05/19/2023]
Abstract
Many of mRNAs synthesized during pollen development are translated after germination, and we hypothesize that they are stored in cytoplasmic granules. We analyzed the cellular localization of the SKS14 and AT59 Arabidopsis mRNAs, which are orthologues of the tobacco NTP303 and tomato LAT59 pollen mRNAs, respectively, by artificially labeling the transcripts with a MS2-GFP chimera. A MATLAB-automated image analysis helped to identify the presence of cytoplasmic SKS14 and AT59 mRNA granules in mature pollen grains. These mRNA granules partially colocalized with VCS and DCP1, two processing body (PB) proteins. Finally, we found a temporal correlation between SKS14 protein accumulation and the disappearance of SKS14 mRNA granules during pollen germination. These results contribute to unveil a mechanism for translational regulation in Arabidopsis thaliana pollen.
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Affiliation(s)
- María R. Scarpin
- Instituto de Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI‐CONICET)Buenos AiresArgentina
| | - Lorena Sigaut
- Instituto de Física de Buenos Aires (IFIBA‐CONICET)Departamento de FísicaFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaBuenos AiresArgentina
| | - Silvio G. Temprana
- Fundación Instituto LeloirIIBBA‐CONICETFacultad de Ciencias Exactas y NaturalesDepartamento de Fisiología y Biología Molecular y CelularUniversidad de Buenos AiresCiudad UniversitariaBuenos AiresArgentina
| | - Graciela L. Boccaccio
- Fundación Instituto LeloirIIBBA‐CONICETFacultad de Ciencias Exactas y NaturalesDepartamento de Fisiología y Biología Molecular y CelularUniversidad de Buenos AiresCiudad UniversitariaBuenos AiresArgentina
| | - Lía I. Pietrasanta
- Instituto de Física de Buenos Aires (IFIBA‐CONICET)Departamento de FísicaFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaBuenos AiresArgentina
- Centro de Microscopías AvanzadasFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaBuenos AiresArgentina
| | - Jorge P. Muschietti
- Instituto de Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI‐CONICET)Buenos AiresArgentina
- Departamento de Biodiversidad y Biología ExperimentalFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaBuenos AiresArgentina
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14
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Abstract
Cells are highly organized entities that rely on intricate addressing mechanisms to sort their constituent molecules to precise subcellular locations. These processes are crucial for cells to maintain their proper organization and carry out specialized functions in the body, consequently genetic perturbations that clog up these addressing systems can contribute to disease aetiology. The trafficking of RNA molecules represents an important layer in the control of cellular organization, a process that is both highly prevalent and for which features of the regulatory machineries have been deeply conserved evolutionarily. RNA localization is commonly driven by trans-regulatory factors, including RNA binding proteins at the core, which recognize specific cis-acting zipcode elements within the RNA transcripts. Here, we first review the functions and biological benefits of intracellular RNA trafficking, from the perspective of both coding and non-coding RNAs. Next, we discuss the molecular mechanisms that modulate this localization, emphasizing the diverse features of the cis- and trans-regulators involved, while also highlighting emerging technologies and resources that will prove instrumental in deciphering RNA targeting pathways. We then discuss recent findings that reveal how co-transcriptional regulatory mechanisms operating in the nucleus can dictate the downstream cytoplasmic localization of RNAs. Finally, we survey the growing number of human diseases in which RNA trafficking pathways are impacted, including spinal muscular atrophy, Alzheimer's disease, fragile X syndrome and myotonic dystrophy. Such examples highlight the need to further dissect RNA localization mechanisms, which could ultimately pave the way for the development of RNA-oriented diagnostic and therapeutic strategies. This article is part of a Special Issue entitled "Biochemistry of Synthetic Biology - Recent Developments" Guest Editor: Dr. Ilka Heinemann and Dr. Patrick O'Donoghue.
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Affiliation(s)
- Ashley Chin
- Institut de recherches cliniques de Montréal (IRCM), 110 Avenue des Pins Ouest, Montreal, Quebec, Canada; Division of Experimental Medicine, McGill University, 1001 Decarie Boulevard, Montreal, Quebec, Canada
| | - Eric Lécuyer
- Institut de recherches cliniques de Montréal (IRCM), 110 Avenue des Pins Ouest, Montreal, Quebec, Canada; Division of Experimental Medicine, McGill University, 1001 Decarie Boulevard, Montreal, Quebec, Canada; Department of Biochemistry and Molecular Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, Canada.
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15
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Zhang Q, Meng X, Li D, Chen S, Luo J, Zhu L, Singer RH, Gu W. Binding of DEAD-box helicase Dhh1 to the 5'-untranslated region of ASH1 mRNA represses localized translation of ASH1 in yeast cells. J Biol Chem 2017; 292:9787-9800. [PMID: 28450395 PMCID: PMC5465500 DOI: 10.1074/jbc.m117.776492] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 04/24/2017] [Indexed: 02/05/2023] Open
Abstract
Local translation of specific mRNAs is regulated by dynamic changes in their subcellular localization, and these changes are due to complex mechanisms controlling cytoplasmic mRNA transport. The budding yeast Saccharomyces cerevisiae is well suited to studying these mechanisms because many of its transcripts are transported from the mother cell to the budding daughter cell. Here, we investigated the translational control of ASH1 mRNA after transport and localization. We show that although ASH1 transcripts were translated after they reached the bud tip, some mRNAs were bound by the RNA-binding protein Puf6 and were non-polysomal. We also found that the DEAD-box helicase Dhh1 complexed with the untranslated ASH1 mRNA and Puf6. Loss of Dhh1 affected local translation of ASH1 mRNA and resulted in delocalization of ASH1 transcript in the bud. Forcibly shifting the non-polysomal ASH1 mRNA into polysomes was associated with Dhh1 dissociation. We further demonstrated that Dhh1 is not recruited to ASH1 mRNA co-transcriptionally, suggesting that it could bind to ASH1 mRNA within the cytoplasm. Of note, Dhh1 bound to the 5'-UTR of ASH1 mRNA and inhibited its translation in vitro These results suggest that after localization to the bud tip, a portion of the localized ASH1 mRNA becomes translationally inactive because of binding of Dhh1 and Puf6 to the 5'- and 3'-UTRs of ASH1 mRNA.
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Affiliation(s)
- Qianjun Zhang
- From the Department of Pathophysiology, Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province 515031, China and
| | - Xiuhua Meng
- the Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Delin Li
- From the Department of Pathophysiology, Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province 515031, China and
| | - Shaoyin Chen
- From the Department of Pathophysiology, Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province 515031, China and
| | - Jianmin Luo
- From the Department of Pathophysiology, Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province 515031, China and
| | - Linjie Zhu
- From the Department of Pathophysiology, Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province 515031, China and
| | - Robert H Singer
- the Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Wei Gu
- From the Department of Pathophysiology, Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou, Guangdong Province 515031, China and
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16
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Das S, Parker JM, Guven C, Wang W, Kriebel PW, Losert W, Larson DR, Parent CA. Adenylyl cyclase mRNA localizes to the posterior of polarized DICTYOSTELIUM cells during chemotaxis. BMC Cell Biol 2017; 18:23. [PMID: 28545392 PMCID: PMC5445419 DOI: 10.1186/s12860-017-0139-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 05/09/2017] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND In Dictyostelium discoideum, vesicular transport of the adenylyl cyclase A (ACA) to the posterior of polarized cells is essential to relay exogenous 3',5'-cyclic adenosine monophosphate (cAMP) signals during chemotaxis and for the collective migration of cells in head-to-tail arrangements called streams. RESULTS Using fluorescence in situ hybridization (FISH), we discovered that the ACA mRNA is asymmetrically distributed at the posterior of polarized cells. Using both standard estimators and Monte Carlo simulation methods, we found that the ACA mRNA enrichment depends on the position of the cell within a stream, with the posterior localization of ACA mRNA being strongest for cells at the end of a stream. By monitoring the recovery of ACA-YFP after cycloheximide (CHX) treatment, we observed that ACA mRNA and newly synthesized ACA-YFP first emerge as fluorescent punctae that later accumulate to the posterior of cells. We also found that the ACA mRNA localization requires 3' ACA cis-acting elements. CONCLUSIONS Together, our findings suggest that the asymmetric distribution of ACA mRNA allows the local translation and accumulation of ACA protein at the posterior of cells. These data represent a novel functional role for localized translation in the relay of chemotactic signal during chemotaxis.
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Affiliation(s)
- Satarupa Das
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, 37 Convent Drive, Bldg.37/Rm2066, NCI, NIH, Bethesda, MD, 20892-4256, USA.,Institute for Physical Science and Technology, Department of Physics, University of Maryland, College Park, MD, 20742, USA
| | - Joshua M Parker
- Institute for Physical Science and Technology, Department of Physics, University of Maryland, College Park, MD, 20742, USA
| | - Can Guven
- Institute for Physical Science and Technology, Department of Physics, University of Maryland, College Park, MD, 20742, USA
| | - Weiye Wang
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, 37 Convent Drive, Bldg.37/Rm2066, NCI, NIH, Bethesda, MD, 20892-4256, USA
| | - Paul W Kriebel
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, 37 Convent Drive, Bldg.37/Rm2066, NCI, NIH, Bethesda, MD, 20892-4256, USA
| | - Wolfgang Losert
- Institute for Physical Science and Technology, Department of Physics, University of Maryland, College Park, MD, 20742, USA
| | - Daniel R Larson
- Laboratory of Receptor Biology and Gene Expression, Center for Cancer Research, NCI, NIH, Bethesda, MD, 20892, USA
| | - Carole A Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, 37 Convent Drive, Bldg.37/Rm2066, NCI, NIH, Bethesda, MD, 20892-4256, USA. .,Institute for Physical Science and Technology, Department of Physics, University of Maryland, College Park, MD, 20742, USA.
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17
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Mechanism and Regulation of Protein Synthesis in Saccharomyces cerevisiae. Genetics 2017; 203:65-107. [PMID: 27183566 DOI: 10.1534/genetics.115.186221] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/24/2016] [Indexed: 12/18/2022] Open
Abstract
In this review, we provide an overview of protein synthesis in the yeast Saccharomyces cerevisiae The mechanism of protein synthesis is well conserved between yeast and other eukaryotes, and molecular genetic studies in budding yeast have provided critical insights into the fundamental process of translation as well as its regulation. The review focuses on the initiation and elongation phases of protein synthesis with descriptions of the roles of translation initiation and elongation factors that assist the ribosome in binding the messenger RNA (mRNA), selecting the start codon, and synthesizing the polypeptide. We also examine mechanisms of translational control highlighting the mRNA cap-binding proteins and the regulation of GCN4 and CPA1 mRNAs.
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18
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Edelmann FT, Schlundt A, Heym RG, Jenner A, Niedner-Boblenz A, Syed MI, Paillart JC, Stehle R, Janowski R, Sattler M, Jansen RP, Niessing D. Molecular architecture and dynamics of ASH1 mRNA recognition by its mRNA-transport complex. Nat Struct Mol Biol 2017; 24:152-161. [PMID: 28092367 DOI: 10.1038/nsmb.3351] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 12/07/2016] [Indexed: 12/20/2022]
Abstract
mRNA localization is an essential mechanism of gene regulation and is required for processes such as stem-cell division, embryogenesis and neuronal plasticity. It is not known which features in the cis-acting mRNA localization elements (LEs) are specifically recognized by motor-containing transport complexes. To the best of our knowledge, no high-resolution structure is available for any LE in complex with its cognate protein complex. Using X-ray crystallography and complementary techniques, we carried out a detailed assessment of an LE of the ASH1 mRNA from yeast, its complex with its shuttling RNA-binding protein She2p, and its highly specific, cytoplasmic complex with She3p. Although the RNA alone formed a flexible stem loop, She2p binding induced marked conformational changes. However, only joining by the unstructured She3p resulted in specific RNA recognition. The notable RNA rearrangements and joint action of a globular and an unfolded RNA-binding protein offer unprecedented insights into the step-wise maturation of an mRNA-transport complex.
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Affiliation(s)
- Franziska Theresia Edelmann
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Andreas Schlundt
- Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Garching, Germany
| | - Roland Gerhard Heym
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Andreas Jenner
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Annika Niedner-Boblenz
- Biomedical Center of the Ludwig-Maximilians-Universität München, Department of Cell Biology, Planegg-Martinsried, Germany
| | | | - Jean-Christophe Paillart
- Architecture et Réactivité de l'ARN, Université de Strasbourg, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Ralf Stehle
- Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Garching, Germany
| | - Robert Janowski
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Center for Integrated Protein Science Munich at Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, Garching, Germany
| | - Ralf-Peter Jansen
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Dierk Niessing
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Biomedical Center of the Ludwig-Maximilians-Universität München, Department of Cell Biology, Planegg-Martinsried, Germany
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19
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Sladewski TE, Trybus KM. A single molecule approach to mRNA transport by a class V myosin. RNA Biol 2014; 11:986-91. [PMID: 25482893 DOI: 10.4161/rna.29947] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
mRNA localization ensures correct spatial and temporal control of protein synthesis in the cell. We show that an in vitro single molecule approach, using purified recombinant full-length proteins and synthesized mRNA, provides insight into the mechanism by which localizing mRNAs are carried to their destination. A messenger ribonucleoprotein (mRNP) complex was reconstituted from a budding yeast class V myosin motor complex (Myo4p-She3p), an mRNA-binding adaptor protein (She2p), and a localizing mRNA (ASH1). The motion of the mRNP was tracked with high spatial (∼10 nm) and temporal (70 ms) resolution. Using this "bottom-up" methodology, we show that mRNA triggers the assembly of a high affinity double-headed motor-mRNA complex that moves continuously for long distances on actin filaments at physiologic ionic strength. Without mRNA, the myosin is monomeric and unable to move continuously on actin. This finding reveals an elegant strategy to ensure that only cargo-bound motors are activated for transport. Increasing the number of localization elements ("zip codes") in the mRNA enhanced both the frequency of motile events and their run length, features which likely enhance cellular localization. Future in vitro reconstitution of mRNPs with kinesin and dynein motors should similarly yield mechanistic insight into mRNA transport by microtubule-based motors.
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Affiliation(s)
- Thomas E Sladewski
- a Department of Molecular Physiology & Biophysics ; University of Vermont ; Burlington , VT USA
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20
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Niedner A, Edelmann FT, Niessing D. Of social molecules: The interactive assembly of ASH1 mRNA-transport complexes in yeast. RNA Biol 2014; 11:998-1009. [PMID: 25482892 PMCID: PMC4615550 DOI: 10.4161/rna.29946] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Asymmetric, motor-protein dependent transport of mRNAs and subsequent localized translation is an important mechanism of gene regulation. Due to the high complexity of such motile particles, our mechanistic understanding of mRNA localization is limited. Over the last two decades, ASH1 mRNA localization in budding yeast has served as comparably simple and accessible model system. Recent advances have helped to draw an increasingly clear picture on the molecular mechanisms governing ASH1 mRNA localization from its co-transcriptional birth to its delivery at the site of destination. These new insights help to better understand the requirement of initial nuclear mRNPs, the molecular basis of specific mRNA-cargo recognition via cis-acting RNA elements, the different stages of RNP biogenesis and reorganization, as well as activation of the motile activity upon cargo binding. We discuss these aspects in context of published findings from other model organisms.
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Affiliation(s)
- Annika Niedner
- a Institute of Structural Biology; Helmholtz Zentrum München - German Center for Environmental Health ; Neuherberg , Germany
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21
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Guydosh NR, Green R. Dom34 rescues ribosomes in 3' untranslated regions. Cell 2014; 156:950-62. [PMID: 24581494 DOI: 10.1016/j.cell.2014.02.006] [Citation(s) in RCA: 257] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 11/18/2013] [Accepted: 02/04/2014] [Indexed: 10/25/2022]
Abstract
Ribosomes that stall before completing peptide synthesis must be recycled and returned to the cytoplasmic pool. The protein Dom34 and cofactors Hbs1 and Rli1 can dissociate stalled ribosomes in vitro, but the identity of targets in the cell is unknown. Here, we extend ribosome profiling methodology to reveal a high-resolution molecular characterization of Dom34 function in vivo. Dom34 removes stalled ribosomes from truncated mRNAs, but, in contrast, does not generally dissociate ribosomes on coding sequences known to trigger stalling, such as polyproline. We also show that Dom34 targets arrested ribosomes near the ends of 3' UTRs. These ribosomes appear to gain access to the 3' UTR via a mechanism that does not require decoding of the mRNA. These results suggest that ribosomes frequently enter downstream noncoding regions and that Dom34 carries out the important task of rescuing them.
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Affiliation(s)
- Nicholas R Guydosh
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Rachel Green
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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22
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Abstract
A comprehensive understanding of RNA structure will provide fundamental insights into the cellular function of both coding and non-coding RNAs. Although many RNA structures have been analysed by traditional biophysical and biochemical methods, the low-throughput nature of these approaches has prevented investigation of the vast majority of cellular transcripts. Triggered by advances in sequencing technology, genome-wide approaches for probing the transcriptome are beginning to reveal how RNA structure affects each step of protein expression and RNA stability. In this Review, we discuss the emerging relationships between RNA structure and the regulation of gene expression.
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23
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Heym RG, Zimmermann D, Edelmann FT, Israel L, Ökten Z, Kovar DR, Niessing D. In vitro reconstitution of an mRNA-transport complex reveals mechanisms of assembly and motor activation. ACTA ACUST UNITED AC 2014; 203:971-84. [PMID: 24368805 PMCID: PMC3871432 DOI: 10.1083/jcb.201302095] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The budding yeast SHE mRNA-transport complex dimerizes to activate processive RNA transport, irrespective of the presence of RNA cargo, and multimerizes upon binding RNAs with multiple localization elements. The assembly and composition of ribonucleic acid (RNA)–transporting particles for asymmetric messenger RNA (mRNA) localization is not well understood. During mitosis of budding yeast, the Swi5p-dependent HO expression (SHE) complex transports a set of mRNAs into the daughter cell. We recombinantly reconstituted the core SHE complex and assessed its properties. The cytoplasmic precomplex contains only one motor and is unable to support continuous transport. However, a defined interaction with a second, RNA-bound precomplex after its nuclear export dimerizes the motor and activates processive RNA transport. The run length observed in vitro is compatible with long-distance transport in vivo. Surprisingly, SHE complexes that either contain or lack RNA cargo show similar motility properties, demonstrating that the RNA-binding protein and not its cargo activates motility. We further show that SHE complexes have a defined size but multimerize into variable particles upon binding of RNAs with multiple localization elements. Based on these findings, we provide an estimate of number, size, and composition of such multimeric SHE particles in the cell.
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Affiliation(s)
- Roland G Heym
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764 Neuherberg, Germany
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24
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Abstract
Myosin 4 protein (Myo4p), one of five distinct myosins of yeast, is dedicated to cytoplasmic transport of two types of cargos, zipcoded messenger ribonucleoprotein particles (mRNPs) and tubular endoplasmic reticulum (tER). Neither cargo binds directly to Myo4p. Instead, swi5p-dependent HO expression 3 protein (She3p) serves as an "adaptor" that contains three binding modules, one for Myo4p and one each for zipcoded mRNP and tER. The assembly of a transport-competent motor complex is poorly understood. Here, we report that Myo4p•She3p forms a stable 1:2 heterotrimer in solution. In the Myo4p•She3p crystal structure, Myo4p's C-terminal domain (CTD) assumes a lobster claw-shaped form, the minor prong of which adheres to a pseudocoiled-coil region of She3p. The extensive Myo4p•She3p interactome buries 3,812 Å(2) surface area and is primarily hydrophobic. Because the Myo4p•She3p heterotrimer contains only one myosin molecule, it is not transport-competent. By stepwise reconstitution, we found a single molecule of synthetic oligonucleotide (representing the mRNA zipcode element) bound to a single tetramer of zipcode binding protein She2p to be sufficient for Myo4p•She3p dimerization. Therefore, cargo initiates cross-linking of two Myo4p•She3p heterotrimers to an ensemble that contains two myosin molecules obligatory for movement. An additional crystal structure comprising an overlapping upstream portion of She3p showed continuation of the pseudocoiled-coil structure and revealed another highly conserved surface region. We suggest this region as a candidate binding site for a yet unidentified tER ligand. We propose a model whereby zipcoded mRNP and/or tER ligands couple two Myo4p•She3p heterotrimers and thereby generate a transport-competent motor complex either for separate transport or cotransport of these two cargos.
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25
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Re A, Joshi T, Kulberkyte E, Morris Q, Workman CT. RNA-protein interactions: an overview. Methods Mol Biol 2014; 1097:491-521. [PMID: 24639174 DOI: 10.1007/978-1-62703-709-9_23] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
RNA binding proteins (RBPs) are key players in the regulation of gene expression. In this chapter we discuss the main protein-RNA recognition modes used by RBPs in order to regulate multiple steps of RNA processing. We discuss traditional and state-of-the-art technologies that can be used to study RNAs bound by individual RBPs, or vice versa, for both in vitro and in vivo methodologies. To help highlight the biological significance of RBP mediated regulation, online resources on experimentally verified protein-RNA interactions are briefly presented. Finally, we present the major tools to computationally infer RNA binding sites according to the modeling features and to the unsupervised or supervised frameworks that are adopted. Since some RNA binding site search algorithms are derived from DNA binding site search algorithms, we discuss the commonalities and novelties introduced to handle both sequence and structural features uniquely characterizing protein-RNA interactions.
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Affiliation(s)
- Angela Re
- University of Trento, Mattarello, Italy
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26
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Single-molecule reconstitution of mRNA transport by a class V myosin. Nat Struct Mol Biol 2013; 20:952-7. [PMID: 23812374 PMCID: PMC3735863 DOI: 10.1038/nsmb.2614] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 05/14/2013] [Indexed: 12/27/2022]
Abstract
Molecular motors are instrumental in mRNA localization, which provides spatial and temporal control of protein expression and function. To obtain mechanistic insight into how a class V myosin transports mRNA, we performed single-molecule in vitro assays on messenger ribonucleoprotein (mRNP) complexes reconstituted from purified proteins and a localizing mRNA found in budding yeast. mRNA is required to form a stable, processive transport complex on actin--an elegant mechanism to ensure that only cargo-bound motors are motile. Increasing the number of localizing elements ('zip codes') on the mRNA, or configuring the track to resemble actin cables, enhanced run length and event frequency. In multi-zip-code mRNPs, motor separation distance varied during a run, thus showing the dynamic nature of the transport complex. Building the complexity of single-molecule in vitro assays is necessary to understand how these complexes function within cells.
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27
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Zhang Y, Ponty Y, Blanchette M, Lécuyer E, Waldispühl J. SPARCS: a web server to analyze (un)structured regions in coding RNA sequences. Nucleic Acids Res 2013; 41:W480-5. [PMID: 23748952 PMCID: PMC3692110 DOI: 10.1093/nar/gkt461] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
More than a simple carrier of the genetic information, messenger RNA (mRNA) coding regions can also harbor functional elements that evolved to control different post-transcriptional processes, such as mRNA splicing, localization and translation. Functional elements in RNA molecules are often encoded by secondary structure elements. In this aticle, we introduce Structural Profile Assignment of RNA Coding Sequences (SPARCS), an efficient method to analyze the (secondary) structure profile of protein-coding regions in mRNAs. First, we develop a novel algorithm that enables us to sample uniformly the sequence landscape preserving the dinucleotide frequency and the encoded amino acid sequence of the input mRNA. Then, we use this algorithm to generate a set of artificial sequences that is used to estimate the Z-score of classical structural metrics such as the sum of base pairing probabilities and the base pairing entropy. Finally, we use these metrics to predict structured and unstructured regions in the input mRNA sequence. We applied our methods to study the structural profile of the ASH1 genes and recovered key structural elements. A web server implementing this discovery pipeline is available at http://csb.cs.mcgill.ca/sparcs together with the source code of the sampling algorithm.
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Affiliation(s)
- Yang Zhang
- School of Computer Science & McGill Centre for Bioinformatics, McGill University, Montréal, H3A 0C6 QC, Canada
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28
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Weis BL, Schleiff E, Zerges W. Protein targeting to subcellular organelles via MRNA localization. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:260-73. [PMID: 23457718 DOI: 10.1016/j.bbamcr.2012.04.004] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Cells have complex membranous organelles for the compartmentalization and the regulation of most intracellular processes. Organelle biogenesis and maintenance requires newly synthesized proteins, each of which needs to go from the ribosome translating its mRNA to the correct membrane for insertion or transclocation to an a organellar subcompartment. Decades of research have revealed how proteins are targeted to the correct organelle and translocated across one or more organelle membranes ro the compartment where they function. The paradigm examples involve interactions between a peptide sequence in the protein, localization factors, and various membrane embedded translocation machineries. Membrane translocation is either cotranslational or posttranslational depending on the protein and target organelle. Meanwhile research in embryos, neurons and yeast revealed an alternative targeting mechanism in which the mRNA is localized and only then translated to synthesize the protein in the correct location. In these cases, the targeting information is coded by the cis-acting sequences in the mRNA ("Zipcodes") that interact with localization factors and, in many cases, are transported by the molecular motors on the cytoskeletal filaments. Recently, evidence has been found for this "mRNA based" mechanism in organelle protein targeting to endoplasmic reticulum, mitochondria, and the photosynthetic membranes within chloroplasts. Here we review known and potential roles of mRNA localization in protein targeting to and within organelles. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids.
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Affiliation(s)
- Benjamin L Weis
- Goether University, Cluster of Excellence Macromolecular Complexes, Institute for Molecular Biosciences, Max-von-Laue Str. 9, D-60438 Frankfort, Germany
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29
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Mauger DM, Siegfried NA, Weeks KM. The genetic code as expressed through relationships between mRNA structure and protein function. FEBS Lett 2013; 587:1180-1188. [PMID: 23499436 PMCID: PMC4269304 DOI: 10.1016/j.febslet.2013.03.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 02/28/2013] [Accepted: 03/01/2013] [Indexed: 02/05/2023]
Abstract
Structured RNA elements within messenger RNA often direct or modulate the cellular production of active proteins. As reviewed here, RNA structures have been discovered that govern nearly every step in protein production: mRNA production and stability; translation initiation, elongation, and termination; protein folding; and cellular localization. Regulatory RNA elements are common within RNAs from every domain of life. This growing body of RNA-mediated mechanisms continues to reveal new ways in which mRNA structure regulates translation. We integrate examples from several different classes of RNA structure-mediated regulation to present a global perspective that suggests that the secondary and tertiary structure of RNA ultimately constitutes an additional level of the genetic code that both guides and regulates protein biosynthesis.
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Affiliation(s)
- David M Mauger
- Department of Chemistry, University of North Carolina Chapel Hill, North Carolina, USA 25599-3290
| | - Nathan A Siegfried
- Department of Chemistry, University of North Carolina Chapel Hill, North Carolina, USA 25599-3290
| | - Kevin M Weeks
- Department of Chemistry, University of North Carolina Chapel Hill, North Carolina, USA 25599-3290
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30
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Charneski CA, Hurst LD. Positively charged residues are the major determinants of ribosomal velocity. PLoS Biol 2013; 11:e1001508. [PMID: 23554576 PMCID: PMC3595205 DOI: 10.1371/journal.pbio.1001508] [Citation(s) in RCA: 200] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 02/01/2013] [Indexed: 11/18/2022] Open
Abstract
Both for understanding mechanisms of disease and for the design of transgenes, it is important to understand the determinants of ribosome velocity, as changes in the rate of translation are important for protein folding, error attenuation, and localization. While there is great variation in ribosomal occupancy along even a single transcript, what determines a ribosome's occupancy is unclear. We examine this issue using data from a ribosomal footprinting assay in yeast. While codon usage is classically considered a major determinant, we find no evidence for this. By contrast, we find that positively charged amino acids greatly retard ribosomes downstream from where they are encoded, consistent with the suggestion that positively charged residues interact with the negatively charged ribosomal exit tunnel. Such slowing is independent of and greater than the average effect owing to mRNA folding. The effect of charged amino acids is additive, with ribosomal occupancy well-predicted by a linear fit to the density of positively charged residues. We thus expect that a translated poly-A tail, encoding for positively charged lysines regardless of the reading frame, would act as a sandtrap for the ribosome, consistent with experimental data.
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Affiliation(s)
| | - Laurence D. Hurst
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
- * E-mail:
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31
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Ouyang Z, Snyder MP, Chang HY. SeqFold: genome-scale reconstruction of RNA secondary structure integrating high-throughput sequencing data. Genome Res 2012; 23:377-87. [PMID: 23064747 PMCID: PMC3561878 DOI: 10.1101/gr.138545.112] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We present an integrative approach, SeqFold, that combines high-throughput RNA structure profiling data with computational prediction for genome-scale reconstruction of RNA secondary structures. SeqFold transforms experimental RNA structure information into a structure preference profile (SPP) and uses it to select stable RNA structure candidates representing the structure ensemble. Under a high-dimensional classification framework, SeqFold efficiently matches a given SPP to the most likely cluster of structures sampled from the Boltzmann-weighted ensemble. SeqFold is able to incorporate diverse types of RNA structure profiling data, including parallel analysis of RNA structure (PARS), selective 2′-hydroxyl acylation analyzed by primer extension sequencing (SHAPE-Seq), fragmentation sequencing (FragSeq) data generated by deep sequencing, and conventional SHAPE data. Using the known structures of a wide range of mRNAs and noncoding RNAs as benchmarks, we demonstrate that SeqFold outperforms or matches existing approaches in accuracy and is more robust to noise in experimental data. Application of SeqFold to reconstruct the secondary structures of the yeast transcriptome reveals the diverse impact of RNA secondary structure on gene regulation, including translation efficiency, transcription initiation, and protein-RNA interactions. SeqFold can be easily adapted to incorporate any new types of high-throughput RNA structure profiling data and is widely applicable to analyze RNA structures in any transcriptome.
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Affiliation(s)
- Zhengqing Ouyang
- Howard Hughes Medical Institute and Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California 94305, USA.
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32
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Inducible control of subcellular RNA localization using a synthetic protein-RNA aptamer interaction. PLoS One 2012; 7:e46868. [PMID: 23056498 PMCID: PMC3466194 DOI: 10.1371/journal.pone.0046868] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Accepted: 09/05/2012] [Indexed: 12/18/2022] Open
Abstract
Evidence is accumulating in support of the functional importance of subcellular RNA localization in diverse biological contexts. In different cell types, distinct RNA localization patterns are frequently observed, and the available data indicate that this is achieved through a series of highly coordinated events. Classically, cis–elements within the RNA to be localized are recognized by RNA-binding proteins (RBPs), which then direct specific localization of a target RNA. Until now, the precise control of the spatiotemporal parameters inherent to regulating RNA localization has not been experimentally possible. Here, we demonstrate the development and use of a chemically–inducible RNA–protein interaction to regulate subcellular RNA localization. Our system is composed primarily of two parts: (i) the Tet Repressor protein (TetR) genetically fused to proteins natively involved in localizing endogenous transcripts; and (ii) a target transcript containing genetically encoded TetR–binding RNA aptamers. TetR–fusion protein binding to the target RNA and subsequent localization of the latter are directly regulated by doxycycline. Using this platform, we demonstrate that enhanced and controlled subcellular localization of engineered transcripts are achievable. We also analyze rules for forward engineering this RNA localization system in an effort to facilitate its straightforward application to studying RNA localization more generally.
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33
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Gonsalvez GB, Long RM. Spatial regulation of translation through RNA localization. F1000 BIOLOGY REPORTS 2012; 4:16. [PMID: 22912650 PMCID: PMC3412389 DOI: 10.3410/b4-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
RNA localization is a mechanism to post-transcriptionally regulate gene
expression. Eukaryotic organisms ranging from fungi to mammals localize mRNAs to
spatially restrict synthesis of specific proteins to distinct regions of the
cytoplasm. In this review, we provide a general summary of RNA localization
pathways in Saccharomyces cerevisiae, Xenopus,
Drosophila and mammalian neurons.
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Affiliation(s)
- Graydon B. Gonsalvez
- Department of Cellular Biology and
Anatomy, Georgia Health Sciences UniversityC2915D,
1459 Laney Walker Blvd., Augusta, GA
30912USA
| | - Roy M. Long
- Department of Microbiology, Immunology
& Molecular Genetics, Medical College of
Wisconsin8701 Watertown Plank Rd., Milwaukee, WI
53226USA
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Darnell JC, Richter JD. Cytoplasmic RNA-binding proteins and the control of complex brain function. Cold Spring Harb Perspect Biol 2012; 4:a012344. [PMID: 22723494 DOI: 10.1101/cshperspect.a012344] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The formation and maintenance of neural circuits in the mammal central nervous system (CNS) require the coordinated expression of genes not just at the transcriptional level, but at the translational level as well. Recent evidence shows that regulated messenger RNA (mRNA) translation is necessary for certain forms of synaptic plasticity, the cellular basis of learning and memory. In addition, regulated translation helps guide axonal growth cones to their targets on other neurons or at the neuromuscular junction. Several neurologic syndromes have been correlated with and indeed may be caused by aberrant translation; one important example is the fragile X mental retardation syndrome. Although translation in the CNS is regulated by multiple mechanisms and factors, we focus this review on regulatory mRNA-binding proteins with particular emphasis on fragile X mental retardation protein (FMRP) and cytoplasmic polyadenylation element binding (CPEB) because they have been shown to be at the nexus of translational control and brain function in health and disease.
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Affiliation(s)
- Jennifer C Darnell
- Department of Molecular Neuro-Oncology, Rockefeller University, New York, New York 10065, USA.
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35
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Jansen RP, Niessing D. Assembly of mRNA-protein complexes for directional mRNA transport in eukaryotes--an overview. Curr Protein Pept Sci 2012; 13:284-93. [PMID: 22708485 PMCID: PMC3474952 DOI: 10.2174/138920312801619493] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 01/10/2012] [Accepted: 01/20/2012] [Indexed: 12/11/2022]
Abstract
At all steps from transcription to translation, RNA-binding proteins play important roles in determining mRNA function. Initially it was believed that for the vast majority of transcripts the role of RNA-binding proteins is limited to general functions such as splicing and translation. However, work from recent years showed that members of this class of proteins also recognize several mRNAs via cis-acting elements for their incorporation into large motor-containing particles. These particles are transported to distant subcellular sites, where they become subsequently translated. This process, called mRNA localization, occurs along microtubules or actin filaments, and involves kinesins, dyneins, as well as myosins. Although mRNA localization has been detected in a large number of organisms from fungi to humans, the underlying molecular machineries are not well understood. In this review we will outline general principles of mRNA localization and highlight three examples, for which a comparably large body of information is available. The first example is She2p/She3p-dependent localization of ASH1 mRNA in budding yeast. It is particularly well suited to highlight the interdependence between different steps of mRNA localization. The second example is Staufen-dependent localization of oskar mRNA in the Drosophila embryo, for which the importance of nuclear events for cytoplasmic localization and translational control has been clearly demonstrated. The third example summarizes Egalitarian/Bicaudal D-dependent mRNA transport events in the oocyte and embryo of Drosophila. We will highlight general themes and differences, point to similarities in other model systems, and raise open questions that might be answered in the coming years.
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Affiliation(s)
- Ralf-Peter Jansen
- Interfaculty Institute for Biochemistry, University of Tübingen, Tübingen, Germany
| | - Dierk Niessing
- Institute of Structural Biology, Helmholtz Zentrum München–German Research Center for Environmental Health, München, Germany
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
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36
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Barberis M. Sic1 as a timer of Clb cyclin waves in the yeast cell cycle--design principle of not just an inhibitor. FEBS J 2012; 279:3386-410. [PMID: 22356687 DOI: 10.1111/j.1742-4658.2012.08542.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Cellular systems biology aims to uncover design principles that describe the properties of biological networks through interaction of their components in space and time. The cell cycle is a complex system regulated by molecules that are integrated into functional modules to ensure genome integrity and faithful cell division. In budding yeast, cyclin-dependent kinases (Cdk1/Clb) drive cell cycle progression, being activated and inactivated in a precise temporal sequence. In this module, which we refer to as the 'Clb module', different Cdk1/Clb complexes are regulated to generate waves of Clb activity, a functional property of cell cycle control. The inhibitor Sic1 plays a critical role in the Clb module by binding to and blocking Cdk1/Clb activity, ultimately setting the timing of DNA replication and mitosis. Fifteen years of research subsequent to the identification of Sic1 have lead to the development of an integrative approach that addresses its role in regulating the Clb module. Sic1 is an intrinsically disordered protein and achieves its inhibitory function by cooperative binding, where different structural regions stretch on the Cdk1/Clb surface. Moreover, Sic1 promotes S phase entry, facilitating Cdk1/Clb5 nuclear transport, and therefore revealing a double function of inhibitor/activator that rationalizes a mechanism to prevent precocious DNA replication. Interestingly, the investigation of Clb temporal dynamics by mathematical modelling and experimental validation provides evidence that Sic1 acts as a timer to coordinate oscillations of Clb cyclin waves. Here we review these findings, focusing on the design principle underlying the Clb module, which highlights the role of Sic1 in regulating phase-specific Cdk1/Clb activities.
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Affiliation(s)
- Matteo Barberis
- Institute for Biology, Theoretical Biophysics, Humboldt University Berlin, Germany.
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37
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Shahbabian K, Chartrand P. Control of cytoplasmic mRNA localization. Cell Mol Life Sci 2012; 69:535-52. [PMID: 21984598 PMCID: PMC11115051 DOI: 10.1007/s00018-011-0814-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 08/09/2011] [Accepted: 09/01/2011] [Indexed: 12/17/2022]
Abstract
mRNA localization is a mechanism used by various organisms to control the spatial and temporal production of proteins. This process is a highly regulated event that requires multiple cis- and trans-acting elements that mediate the accurate localization of target mRNAs. The intrinsic nature of localization elements, together with their interaction with different RNA-binding proteins, establishes control mechanisms that can oversee the transcript from its birth in the nucleus to its specific final destination. In this review, we aim to summarize the different mechanisms of mRNA localization, with a particular focus on the various control mechanisms that affect the localization of mRNAs in the cytoplasm.
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Affiliation(s)
- Karen Shahbabian
- Department of Biochemistry, Université de Montréal, 2900 Edouard-Montpetit, Montréal, Qc Canada
| | - Pascal Chartrand
- Department of Biochemistry, Université de Montréal, 2900 Edouard-Montpetit, Montréal, Qc Canada
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38
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An intracellular transmission control protocol: assembly and transport of ribonucleoprotein complexes. Curr Opin Cell Biol 2012; 24:202-10. [PMID: 22278045 DOI: 10.1016/j.ceb.2011.12.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 12/21/2011] [Accepted: 12/27/2011] [Indexed: 12/31/2022]
Abstract
Initially assumed to be a special feature of highly polarized eukaryotic cells, recent evidence suggests that mRNA localization coupled with local translation is a widespread strategy for spatial restriction of protein synthesis within cells. Genome-wide analyses and live imaging approaches have shed new light on the prevalence and the mechanistic details of this phenomenon. Here we review some of the recent findings that have emerged from research from the RNA localization field, from the birth of mRNAs in the nucleus, to their delivery at specific sites within the cytoplasm.
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Endoh T, Kawasaki Y, Sugimoto N. Synchronized translation for detection of temporal stalling of ribosome during single-turnover translation. Anal Chem 2011; 84:857-61. [PMID: 22221219 DOI: 10.1021/ac202712g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Arrhythmic translation caused by temporal stalling of ribosome during translation elongation is essential for gene expression and protein folding. To analyze the positions of the temporarily stalled ribosome and length of the stalling, the ribosomes must be synchronized during translation elongation. In this study, we designed a two-step translation reaction to synchronize the ribosome during a single-turnover translation. First, ribosomes decoding mRNA were artificially and specifically halted before isoleucine codon by reducing isoleucyl-tRNA synthetase from reaction mixture of in vitro translation. Then, translation elongation was restarted simultaneously to synchronize the translation. It enabled evaluation of translation elongation with time resolving capacity shorter than ever before. In addition, position-specific incorporation of fluorescent amino acid and mass spectrometry analyses enabled trace of translation elongation after gel electrophoresis and accurate determination of ribosome positions temporarily stalled before rare codons, respectively. The synchronized translation demonstrated here would be useful to evaluate trans- and cis-elements that affect rate of the translation elongation.
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40
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Heym RG, Niessing D. Principles of mRNA transport in yeast. Cell Mol Life Sci 2011; 69:1843-53. [PMID: 22159587 PMCID: PMC3350770 DOI: 10.1007/s00018-011-0902-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 11/20/2011] [Accepted: 11/28/2011] [Indexed: 12/20/2022]
Abstract
mRNA localization and localized translation is a common mechanism by which cellular asymmetry is achieved. In higher eukaryotes the mRNA transport machinery is required for such diverse processes as stem cell division and neuronal plasticity. Because mRNA localization in metazoans is highly complex, studies at the molecular level have proven to be cumbersome. However, active mRNA transport has also been reported in fungi including Saccharomyces cerevisiae, Ustilago maydis and Candida albicans, in which these events are less difficult to study. Amongst them, budding yeast S. cerevisiae has yielded mechanistic insights that exceed our understanding of other mRNA localization events to date. In contrast to most reviews, we refrain here from summarizing mRNA localization events from different organisms. Instead we give an in-depth account of ASH1 mRNA localization in budding yeast. This approach is particularly suited to providing a more holistic view of the interconnection between the individual steps of mRNA localization, from transcriptional events to cytoplasmic mRNA transport and localized translation. Because of our advanced mechanistic understanding of mRNA localization in yeast, the present review may also be informative for scientists working, for example, on mRNA localization in embryogenesis or in neurons.
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Affiliation(s)
- Roland Gerhard Heym
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, 81377 Munich, Germany
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Dierk Niessing
- Institute of Structural Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, 81377 Munich, Germany
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
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41
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CPEB2-eEF2 interaction impedes HIF-1α RNA translation. EMBO J 2011; 31:959-71. [PMID: 22157746 DOI: 10.1038/emboj.2011.448] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2011] [Accepted: 11/15/2011] [Indexed: 12/21/2022] Open
Abstract
Translation of mRNA into protein proceeds in three phases: initiation, elongation, and termination. Regulated translation allows the prompt production of selective proteins in response to physiological needs and is often controlled by sequence-specific RNA-binding proteins that function at initiation. Whether the elongation phase of translation can be modulated individually by trans-acting factors to synthesize polypeptides at variable rates remains to be determined. Here, we demonstrate that the RNA-binding protein, cytoplasmic polyadenylation element binding protein (CPEB)2, interacts with the elongation factor, eEF2, to reduce eEF2/ribosome-triggered GTP hydrolysis in vitro and slow down peptide elongation of CPEB2-bound RNA in vivo. The interaction of CPEB2 with eEF2 downregulates HIF-1α RNA translation under normoxic conditions; however, when cells encounter oxidative stress, CPEB2 dissociates from HIF-1α RNA, leading to rapid synthesis of HIF-1α for hypoxic adaptation. This study delineates the molecular mechanism of CPEB2-repressed translation and presents a unique model for controlling transcript-selective translation at elongation.
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42
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Translation initiation factors and active sites of protein synthesis co-localize at the leading edge of migrating fibroblasts. Biochem J 2011; 438:217-27. [PMID: 21539520 DOI: 10.1042/bj20110435] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cell migration is a highly controlled essential cellular process, often dysregulated in tumour cells, dynamically controlled by the architecture of the cell. Studies involving cellular fractionation and microarray profiling have previously identified functionally distinct mRNA populations specific to cellular organelles and architectural compartments. However, the interaction between the translational machinery itself and cellular structures is relatively unexplored. To help understand the role for the compartmentalization and localized protein synthesis in cell migration, we have used scanning confocal microscopy, immunofluorescence and a novel ribopuromycylation method to visualize translating ribosomes. In the present study we show that eIFs (eukaryotic initiation factors) localize to the leading edge of migrating MRC5 fibroblasts in a process dependent on TGN (trans-Golgi network) to plasma membrane vesicle transport. We show that eIF4E and eIF4GI are associated with the Golgi apparatus and membrane microdomains, and that a proportion of these proteins co-localize to sites of active translation at the leading edge of migrating cells.
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43
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Müller M, Heym RG, Mayer A, Kramer K, Schmid M, Cramer P, Urlaub H, Jansen RP, Niessing D. A cytoplasmic complex mediates specific mRNA recognition and localization in yeast. PLoS Biol 2011; 9:e1000611. [PMID: 21526221 PMCID: PMC3079584 DOI: 10.1371/journal.pbio.1000611] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 03/10/2011] [Indexed: 11/18/2022] Open
Abstract
The localization of ash mRNA in yeast requires the binding of She2p and the myosin adaptor protein She3p to its localization element, which is highly specific and leads to the assembly of stable transport complexes. In eukaryotes, hundreds of mRNAs are localized by specialized transport complexes. For localization, transcripts are recognized by RNA-binding proteins and incorporated into motor-containing messenger ribonucleoprotein particles (mRNPs). To date, the molecular assembly of such mRNPs is not well understood and most details on cargo specificity remain unresolved. We used ASH1-mRNA transport in yeast to provide a first assessment of where and how localizing mRNAs are specifically recognized and incorporated into mRNPs. By using in vitro–interaction and reconstitution assays, we found that none of the implicated mRNA-binding proteins showed highly specific cargo binding. Instead, we identified the cytoplasmic myosin adapter She3p as additional RNA-binding protein. We further found that only the complex of the RNA-binding proteins She2p and She3p achieves synergistic cargo binding, with an at least 60-fold higher affinity for localizing mRNAs when compared to control RNA. Mutational studies identified a C-terminal RNA-binding fragment of She3p to be important for synergistic RNA binding with She2p. The observed cargo specificity of the ternary complex is considerably higher than previously reported for localizing mRNAs. It suggests that RNA binding for mRNP localization generally exhibits higher selectivity than inferred from previous in vitro data. This conclusion is fully consistent with a large body of in vivo evidence from different organisms. Since the ternary yeast complex only assembles in the cytoplasm, specific mRNA recognition might be limited to the very last steps of mRNP assembly. Remarkably, the mRNA itself triggers the assembly of mature, motor-containing complexes. Our reconstitution of a major portion of the mRNA-transport complex offers new and unexpected insights into the molecular assembly of specific, localization-competent mRNPs and provides an important step forward in our mechanistic understanding of mRNA localization in general. In eukaryotes, the majority of cells are asymmetric and a way to establish such polarity is directional transport of macromolecules along cytoskeletal filaments. Among the cargoes transported, mRNAs play an essential role, as their localized translation contributes significantly to the generation of asymmetry. To date, hundreds of asymmetrically localized mRNAs in various organisms have been identified. These mRNAs are recognized by RNA-binding proteins and incorporated into large motor-containing messenger ribonucleoprotein particles (mRNPs) whose molecular assembly is poorly understood. In this study, we used the well-characterized process of ASH1-mRNA transport in Saccharomyces cerevisiae to address the question of how localizing mRNAs are recognized and specifically incorporated into mRNPs. Surprisingly, we found that the previously implicated mRNA-binding proteins She2p and Puf6p do not bind to cargo mRNAs with high specificity. Instead, the cytoplasmic motor-adapter protein She3p is responsible for synergistic cargo binding with She2p and for the stable incorporation of specific localizing mRNA into the transport complex. We propose that the specific recognition of localizing mRNAs happens at the very last step of cytoplasmic mRNP maturation. Other organisms might employ similar mechanisms to establish cellular polarity.
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Affiliation(s)
- Marisa Müller
- Institute of Structural Biology, Helmholtz Zentrum München–German Research Center for Environmental Health, München, Germany
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
| | - Roland Gerhard Heym
- Institute of Structural Biology, Helmholtz Zentrum München–German Research Center for Environmental Health, München, Germany
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
| | - Andreas Mayer
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
| | - Katharina Kramer
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Maria Schmid
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
| | - Patrick Cramer
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
- Center for Integrated Protein Science CIPSM, München, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Ralf-Peter Jansen
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
- Interfaculty Institute for Biochemistry, University of Tübingen, Tübingen, Germany
| | - Dierk Niessing
- Institute of Structural Biology, Helmholtz Zentrum München–German Research Center for Environmental Health, München, Germany
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University, München, Germany
- * E-mail:
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44
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Liao G, Ma X, Liu G. An RNA-zipcode-independent mechanism that localizes Dia1 mRNA to the perinuclear ER through interactions between Dia1 nascent peptide and Rho-GTP. J Cell Sci 2011; 124:589-99. [PMID: 21266463 DOI: 10.1242/jcs.072421] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Signal-peptide-mediated ER localization of mRNAs encoding for membrane and secreted proteins, and RNA-zipcode-mediated intracellular targeting of mRNAs encoding for cytosolic proteins are two well-known mechanisms for mRNA localization. Here, we report a previously unidentified mechanism by which mRNA encoding for Dia1, a cytosolic protein without the signal peptide, is localized to the perinuclear ER in an RNA-zipcode-independent manner in fibroblasts. Dia1 mRNA localization is also independent of the actin and microtubule cytoskeleton but requires translation and the association of Dia1 nascent peptide with the ribosome-mRNA complex. Sequence mapping suggests that interactions of the GTPase binding domain of Dia1 peptide with active Rho are important for Dia1 mRNA localization. This mechanism can override the β-actin RNA zipcode and redirect β-actin mRNA to the perinuclear region, providing a new way to manipulate intracellular mRNA localization.
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Affiliation(s)
- Guoning Liao
- Center for Cell Biology and Cancer Research, Albany Medical College, Albany, NY 12208, USA
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45
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Abstract
RNA localisation is an important mode of delivering proteins to their site of function. Cis-acting signals within the RNAs, which can be thought of as zip-codes, determine the site of localisation. There are few examples of fully characterised RNA signals, but the signals are thought to be defined through a combination of primary, secondary, and tertiary structures. In this chapter, we describe a selection of computational methods for predicting RNA secondary structure, identifying localisation signals, and searching for similar localisation signals on a genome-wide scale. The chapter is aimed at the biologist rather than presenting the details of each of the individual methods.
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46
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Powrie EA, Zenklusen D, Singer RH. A nucleoporin, Nup60p, affects the nuclear and cytoplasmic localization of ASH1 mRNA in S. cerevisiae. RNA (NEW YORK, N.Y.) 2011; 17:134-144. [PMID: 21036941 PMCID: PMC3004054 DOI: 10.1261/rna.1210411] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Accepted: 09/27/2010] [Indexed: 05/30/2023]
Abstract
The biogenesis of a localization-competent mRNP begins in the nucleus. It is thought that the coordinated action of nuclear and cytoplasmic components of the localization machinery is required for the efficient export and subsequent subcellular localization of these mRNAs in the cytoplasm. Using quantitative poly(A)(+) and transcript-specific fluorescent in situ hybridization, we analyzed different nonessential nucleoporins and nuclear pore-associated proteins for their potential role in mRNA export and localization. We found that Nup60p, a nuclear pore protein located on the nucleoplasmic side of the nuclear pore complex, was required for the mRNA localization pathway. In a Δnup60 background, localized mRNAs were preferentially retained within the nucleus compared to nonlocalized transcripts. However, the export block was only partial and some transcripts could still reach the cytoplasm. Importantly, downstream processes were also affected. Localization of ASH1 and IST2 mRNAs to the bud was impaired in the Δnup60 background, suggesting that the assembly of a localization competent mRNP ("locasome") was inhibited when NUP60 was deleted. These results demonstrate transcript specificity of a nuclear mRNA retention defect and identify a specific nucleoporin as a functional component of the localization pathway in budding yeast.
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Affiliation(s)
- Erin A Powrie
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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47
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Ahmed F, Benedito VA, Zhao PX. Mining Functional Elements in Messenger RNAs: Overview, Challenges, and Perspectives. FRONTIERS IN PLANT SCIENCE 2011; 2:84. [PMID: 22639614 PMCID: PMC3355573 DOI: 10.3389/fpls.2011.00084] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 11/03/2011] [Indexed: 05/03/2023]
Abstract
Eukaryotic messenger RNA (mRNA) contains not only protein-coding regions but also a plethora of functional cis-elements that influence or coordinate a number of regulatory aspects of gene expression, such as mRNA stability, splicing forms, and translation rates. Understanding the rules that apply to each of these element types (e.g., whether the element is defined by primary or higher-order structure) allows for the discovery of novel mechanisms of gene expression as well as the design of transcripts with controlled expression. Bioinformatics plays a major role in creating databases and finding non-evident patterns governing each type of eukaryotic functional element. Much of what we currently know about mRNA regulatory elements in eukaryotes is derived from microorganism and animal systems, with the particularities of plant systems lagging behind. In this review, we provide a general introduction to the most well-known eukaryotic mRNA regulatory motifs (splicing regulatory elements, internal ribosome entry sites, iron-responsive elements, AU-rich elements, zipcodes, and polyadenylation signals) and describe available bioinformatics resources (databases and analysis tools) to analyze eukaryotic transcripts in search of functional elements, focusing on recent trends in bioinformatics methods and tool development. We also discuss future directions in the development of better computational tools based upon current knowledge of these functional elements. Improved computational tools would advance our understanding of the processes underlying gene regulations. We encourage plant bioinformaticians to turn their attention to this subject to help identify novel mechanisms of gene expression regulation using RNA motifs that have potentially evolved or diverged in plant species.
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Affiliation(s)
- Firoz Ahmed
- Bioinformatics Laboratory, Plant Biology Division, Samuel Roberts Noble FoundationArdmore, OK, USA
| | - Vagner A. Benedito
- Genetics and Developmental Biology, Plant and Soil Sciences Division, West Virginia UniversityMorgantown, WV, USA
| | - Patrick Xuechun Zhao
- Bioinformatics Laboratory, Plant Biology Division, Samuel Roberts Noble FoundationArdmore, OK, USA
- *Correspondence: Patrick Xuechun Zhao, Bioinformatics Laboratory, Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA e-mail:
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48
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Yasuda K, Kotani T, Ota R, Yamashita M. Transgenic zebrafish reveals novel mechanisms of translational control of cyclin B1 mRNA in oocytes. Dev Biol 2010; 348:76-86. [DOI: 10.1016/j.ydbio.2010.09.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 09/16/2010] [Accepted: 09/17/2010] [Indexed: 12/21/2022]
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Three-dimensional tracking of single mRNA particles in Saccharomyces cerevisiae using a double-helix point spread function. Proc Natl Acad Sci U S A 2010; 107:17864-71. [PMID: 20921361 DOI: 10.1073/pnas.1012868107] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Optical imaging of single biomolecules and complexes in living cells provides a useful window into cellular processes. However, the three-dimensional dynamics of most important biomolecules in living cells remains essentially uncharacterized. The precise subcellular localization of mRNA-protein complexes plays a critical role in the spatial and temporal control of gene expression, and a full understanding of the control of gene expression requires precise characterization of mRNA transport dynamics beyond the optical diffraction limit. In this paper, we describe three-dimensional tracking of single mRNA particles with 25-nm precision in the x and y dimensions and 50-nm precision in the z dimension in live budding yeast cells using a microscope with a double-helix point spread function. Two statistical methods to detect intermittently confined and directed transport were used to quantify the three-dimensional trajectories of mRNA for the first time, using ARG3 mRNA as a model. Measurements and analysis show that the dynamics of ARG3 mRNA molecules are mostly diffusive, although periods of non-Brownian confinement and directed transport are observed. The quantitative methods detailed in this paper can be broadly applied to the study of mRNA localization and the dynamics of diverse other biomolecules in a wide variety of cell types.
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Kertesz M, Wan Y, Mazor E, Rinn JL, Nutter RC, Chang HY, Segal E. Genome-wide measurement of RNA secondary structure in yeast. Nature 2010; 467:103-7. [PMID: 20811459 DOI: 10.1038/nature09322] [Citation(s) in RCA: 588] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 06/28/2010] [Indexed: 01/25/2023]
Abstract
The structures of RNA molecules are often important for their function and regulation, yet there are no experimental techniques for genome-scale measurement of RNA structure. Here we describe a novel strategy termed parallel analysis of RNA structure (PARS), which is based on deep sequencing fragments of RNAs that were treated with structure-specific enzymes, thus providing simultaneous in vitro profiling of the secondary structure of thousands of RNA species at single nucleotide resolution. We apply PARS to profile the secondary structure of the messenger RNAs (mRNAs) of the budding yeast Saccharomyces cerevisiae and obtain structural profiles for over 3,000 distinct transcripts. Analysis of these profiles reveals several RNA structural properties of yeast transcripts, including the existence of more secondary structure over coding regions compared with untranslated regions, a three-nucleotide periodicity of secondary structure across coding regions and an anti-correlation between the efficiency with which an mRNA is translated and the structure over its translation start site. PARS is readily applicable to other organisms and to profiling RNA structure in diverse conditions, thus enabling studies of the dynamics of secondary structure at a genomic scale.
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Affiliation(s)
- Michael Kertesz
- Dept. of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yue Wan
- Howard Hughes Medical Institute, Program in Epithelial Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Elad Mazor
- Dept. of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - John L Rinn
- The Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | | | - Howard Y Chang
- Howard Hughes Medical Institute, Program in Epithelial Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Eran Segal
- Dept. of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel.,Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
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