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Giambruno R, Zacco E, Ugolini C, Vandelli A, Mulroney L, D’Onghia M, Giuliani B, Criscuolo E, Castelli M, Clementi N, Clementi M, Mancini N, Bonaldi T, Gustincich S, Leonardi T, Tartaglia GG, Nicassio F. Unveiling the role of PUS7-mediated pseudouridylation in host protein interactions specific for the SARS-CoV-2 RNA genome. Mol Ther Nucleic Acids 2023; 34:102052. [PMID: 38028201 PMCID: PMC10630655 DOI: 10.1016/j.omtn.2023.102052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 10/05/2023] [Indexed: 12/01/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a positive single-stranded RNA virus, engages in complex interactions with host cell proteins throughout its life cycle. While these interactions enable the host to recognize and inhibit viral replication, they also facilitate essential viral processes such as transcription, translation, and replication. Many aspects of these virus-host interactions remain poorly understood. Here, we employed the catRAPID algorithm and utilized the RNA-protein interaction detection coupled with mass spectrometry technology to predict and validate the host proteins that specifically bind to the highly structured 5' and 3' terminal regions of the SARS-CoV-2 RNA. Among the interactions identified, we prioritized pseudouridine synthase PUS7, which binds to both ends of the viral RNA. Using nanopore direct RNA sequencing, we discovered that the viral RNA undergoes extensive post-transcriptional modifications. Modified consensus regions for PUS7 were identified at both terminal regions of the SARS-CoV-2 RNA, including one in the viral transcription regulatory sequence leader. Collectively, our findings offer insights into host protein interactions with the SARS-CoV-2 UTRs and highlight the likely significance of pseudouridine synthases and other post-transcriptional modifications in the viral life cycle. This new knowledge enhances our understanding of virus-host dynamics and could inform the development of targeted therapeutic strategies.
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Affiliation(s)
- Roberto Giambruno
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, 20139 Milano, Italy
- Institute of Biomedical Technologies, National Research Council, 20090 Segrate, Italy
| | - Elsa Zacco
- Central RNA and RNA Systems Biology Labs, Centre for Human Technologies (CHT), Istituto Italiano di Tecnologia (IIT), 16152 Genova, Italy
| | - Camilla Ugolini
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, 20139 Milano, Italy
- Department of Oncology and Hematology-Oncology, University of Milan, 20122 Milano, Italy
| | - Andrea Vandelli
- Central RNA and RNA Systems Biology Labs, Centre for Human Technologies (CHT), Istituto Italiano di Tecnologia (IIT), 16152 Genova, Italy
- Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
| | - Logan Mulroney
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, 20139 Milano, Italy
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, Cambridgeshire CB10 1SD, UK
- Epigenetics and Neurobiology Unit, European Molecular Biology Laboratory (EMBL), Monterotondo, RM 00015, Italy
| | - Manfredi D’Onghia
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, 20139 Milano, Italy
| | - Bianca Giuliani
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, 20139 Milano, Italy
| | - Elena Criscuolo
- Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, 20132 Milan, Italy
| | - Matteo Castelli
- Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, 20132 Milan, Italy
| | - Nicola Clementi
- Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, 20132 Milan, Italy
- Laboratory of Medical Microbiology and Virology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
| | - Massimo Clementi
- Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, 20132 Milan, Italy
- Laboratory of Medical Microbiology and Virology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
| | - Nicasio Mancini
- Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, 20132 Milan, Italy
- Laboratory of Medical Microbiology and Virology, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
| | - Tiziana Bonaldi
- Department of Experimental Oncology, European Institute of Oncology IRCCS, 20139 Milano, Italy
- Department of Oncology and Hematology-Oncology, University of Milan, 20122 Milano, Italy
| | - Stefano Gustincich
- Central RNA and RNA Systems Biology Labs, Centre for Human Technologies (CHT), Istituto Italiano di Tecnologia (IIT), 16152 Genova, Italy
| | - Tommaso Leonardi
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, 20139 Milano, Italy
| | - Gian Gaetano Tartaglia
- Central RNA and RNA Systems Biology Labs, Centre for Human Technologies (CHT), Istituto Italiano di Tecnologia (IIT), 16152 Genova, Italy
- Catalan Institution for Research and Advanced Studies, ICREA, 08010 Barcelona, Spain
| | - Francesco Nicassio
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, 20139 Milano, Italy
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Pourciau C, Yakhnin H, Pannuri A, Gorelik MG, Lai YJ, Romeo T, Babitzke P. CsrA coordinates the expression of ribosome hibernation and anti-σ factor proteins. mBio 2023; 14:e0258523. [PMID: 37943032 PMCID: PMC10746276 DOI: 10.1128/mbio.02585-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 10/02/2023] [Indexed: 11/10/2023] Open
Abstract
Bacterial growth rate varies due to changing physiological signals and is fundamentally dependent on protein synthesis. Consequently, cells alter their transcription and translation machinery to optimize the capacity for protein production under varying conditions and growth rates. Our findings demonstrate that the post-transcriptional regulator CsrA in Escherichia coli controls the expression of genes that participate in these processes. During exponential growth, CsrA represses the expression of proteins that alter or inhibit RNA polymerase (RNAP) and ribosome activity, including the ribosome hibernation factors RMF, RaiA, YqjD, ElaB, YgaM, and SRA, as well as the anti-σ70 factor, Rsd. Upon entry into the stationary phase, RaiA, YqjD, ElaB, and SRA expression was derepressed and that of RMF, YgaM, and Rsd was activated in the presence of CsrA. This pattern of gene expression likely supports global protein expression during active growth and helps limit protein production to a basal level when nutrients are limited. In addition, we identified genes encoding the paralogous C-tail anchored inner membrane proteins YqjD and ElaB as robust, direct targets of CsrA-mediated translational repression. These proteins bind ribosomes and mediate their localization to the inner cell membrane, impacting a variety of processes including protein expression and membrane integrity. Previous studies found that YqjD overexpression inhibits cell growth, suggesting that appropriate regulation of YqjD expression might play a key role in cell viability. CsrA-mediated regulation of yqjD and ribosome hibernation factors reveals a new role for CsrA in appropriating cellular resources for optimum growth under varying conditions.IMPORTANCEThe Csr/Rsm system (carbon storage regulator or repressor of stationary phase metabolites) is a global post-transcriptional regulatory system that coordinates and responds to environmental cues and signals, facilitating the transition between active growth and stationary phase. Another key determinant of bacterial lifestyle decisions is the management of the cellular gene expression machinery. Here, we investigate the connection between these two processes in Escherichia coli. Disrupted regulation of the transcription and translation machinery impacts many cellular functions, including gene expression, growth, fitness, and stress resistance. Elucidating the role of the Csr system in controlling the activity of RNAP and ribosomes advances our understanding of mechanisms controlling bacterial growth. A more complete understanding of these processes could lead to the improvement of therapeutic strategies for recalcitrant infections.
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Affiliation(s)
- Christine Pourciau
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
- Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Helen Yakhnin
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Archanna Pannuri
- Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Mark G. Gorelik
- Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Ying-Jung Lai
- Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Tony Romeo
- Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, USA
| | - Paul Babitzke
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
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Campagnola G, Peersen O. Co-folding and RNA activation of poliovirus 3C pro polyprotein precursors. J Biol Chem 2023; 299:105258. [PMID: 37717698 PMCID: PMC10590986 DOI: 10.1016/j.jbc.2023.105258] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 09/05/2023] [Accepted: 09/08/2023] [Indexed: 09/19/2023] Open
Abstract
Positive-strand RNA viruses use long open reading frames to express large polyproteins that are processed into individual proteins by viral proteases. Polyprotein processing is highly regulated and yields intermediate species with different functions than the fully processed proteins, increasing the biochemical diversity of the compact viral genome while also presenting challenges in that proteins must remain stably folded in multiple contexts. We have used circular dichroism spectroscopy and single molecule microscopy to examine the solution structure and self-association of the poliovirus P3 region protein composed of membrane binding 3A, RNA priming 3B (VPg), 3Cpro protease, and 3Dpol RNA-dependent RNA polymerase proteins. Our data indicate that co-folding interactions within the 3ABC segment stabilize the conformational state of the 3C protease region, and this stabilization requires the full-length 3A and 3B proteins. Enzymatic activity assays show that 3ABC is also an active protease, and it cleaves peptide substrates at rates comparable to 3Cpro. The cleavage of a larger polyprotein substrate is stimulated by the addition of RNA, and 3ABCpro becomes 20-fold more active than 3Cpro in the presence of stoichiometric amounts of viral cre RNA. The data suggest that co-folding within the 3ABC region results in a protease that can be highly activated toward certain cleavage sites by localization to specific RNA elements within the viral replication center, providing a mechanism for regulating viral polyprotein processing.
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Affiliation(s)
- Grace Campagnola
- Department of Biochemistry & Molecular Birology, Colorado State University, Fort Collins, Colorado, USA
| | - Olve Peersen
- Department of Biochemistry & Molecular Birology, Colorado State University, Fort Collins, Colorado, USA.
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Esteban‐Serna S, McCaughan H, Granneman S. Advantages and limitations of UV cross-linking analysis of protein-RNA interactomes in microbes. Mol Microbiol 2023; 120:477-489. [PMID: 37165708 PMCID: PMC10952675 DOI: 10.1111/mmi.15073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/28/2023] [Accepted: 04/30/2023] [Indexed: 05/12/2023]
Abstract
RNA-binding proteins (RBPs) govern the lifespan of nearly all transcripts and play key roles in adaptive responses in microbes. A robust approach to examine protein-RNA interactions involves irradiating cells with UV light to form covalent adducts between RBPs and their cognate RNAs. Combined with RNA or protein purification, these procedures can provide global RBP censuses or transcriptomic maps for all target sequences of a single protein in living cells. The recent development of novel methods has quickly populated the RBP landscape in microorganisms. Here, we provide an overview of prominent UV cross-linking techniques which have been applied to investigate RNA interactomes in microbes. By assessing their advantages and caveats, this technical evaluation intends to guide the selection of appropriate methods and experimental design as well as to encourage the use of complementary UV-dependent techniques to inspect RNA-binding activity.
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Affiliation(s)
- Sofia Esteban‐Serna
- Centre for Engineering Biology, School of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Hugh McCaughan
- Centre for Engineering Biology, School of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Sander Granneman
- Centre for Engineering Biology, School of Biological SciencesUniversity of EdinburghEdinburghUK
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Agarwal A, Kant S, Bahadur RP. Efficient mapping of RNA-binding residues in RNA-binding proteins using local sequence features of binding site residues in protein-RNA complexes. Proteins 2023; 91:1361-1379. [PMID: 37254800 DOI: 10.1002/prot.26528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 04/13/2023] [Accepted: 05/02/2023] [Indexed: 06/01/2023]
Abstract
Protein-RNA interactions play vital roles in plethora of biological processes such as regulation of gene expression, protein synthesis, mRNA processing and biogenesis. Identification of RNA-binding residues (RBRs) in proteins is essential to understand RNA-mediated protein functioning, to perform site-directed mutagenesis and to develop novel targeted drug therapies. Moreover, the extensive gap between sequence and structural data restricts the identification of binding sites in unsolved structures. However, efficient use of computational methods demanding only sequence to identify binding residues can bridge this huge sequence-structure gap. In this study, we have extensively studied protein-RNA interface in known RNA-binding proteins (RBPs). We find that the interface is highly enriched in basic and polar residues with Gly being the most common interface neighbor. We investigated several amino acid features and developed a method to predict putative RBRs from amino acid sequence. We have implemented balanced random forest (BRF) classifier with local residue features of protein sequences for prediction. With 5-fold cross-validations, the sequence pattern derived dipeptide composition based BRF model (DCP-BRF) resulted in an accuracy of 87.9%, specificity of 88.8%, sensitivity of 82.2%, Mathew's correlation coefficient of 0.60 and AUC of 0.93, performing better than few existing methods. We further validated our prediction model on known human RBPs through RBR prediction and could map ~54% of them. Further, knowledge of binding site preferences obtained from computational predictions combined with experimental validations of potential RNA binding sites can enhance our understanding of protein-RNA interactions. This may serve to accelerate investigations on functional roles of many novel RBPs.
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Affiliation(s)
- Ankita Agarwal
- School of Bio Science, Indian Institute of Technology Kharagpur, Kharagpur, India
- Computational Structural Biology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Shri Kant
- Computational Structural Biology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Ranjit Prasad Bahadur
- Computational Structural Biology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
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6
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Ebersberger S, Hipp C, Mulorz MM, Buchbender A, Hubrich D, Kang HS, Martínez-Lumbreras S, Kristofori P, Sutandy FXR, Llacsahuanga Allcca L, Schönfeld J, Bakisoglu C, Busch A, Hänel H, Tretow K, Welzel M, Di Liddo A, Möckel MM, Zarnack K, Ebersberger I, Legewie S, Luck K, Sattler M, König J. FUBP1 is a general splicing factor facilitating 3' splice site recognition and splicing of long introns. Mol Cell 2023:S1097-2765(23)00516-6. [PMID: 37506698 DOI: 10.1016/j.molcel.2023.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 05/19/2023] [Accepted: 07/03/2023] [Indexed: 07/30/2023]
Abstract
Splicing of pre-mRNAs critically contributes to gene regulation and proteome expansion in eukaryotes, but our understanding of the recognition and pairing of splice sites during spliceosome assembly lacks detail. Here, we identify the multidomain RNA-binding protein FUBP1 as a key splicing factor that binds to a hitherto unknown cis-regulatory motif. By collecting NMR, structural, and in vivo interaction data, we demonstrate that FUBP1 stabilizes U2AF2 and SF1, key components at the 3' splice site, through multivalent binding interfaces located within its disordered regions. Transcriptional profiling and kinetic modeling reveal that FUBP1 is required for efficient splicing of long introns, which is impaired in cancer patients harboring FUBP1 mutations. Notably, FUBP1 interacts with numerous U1 snRNP-associated proteins, suggesting a unique role for FUBP1 in splice site bridging for long introns. We propose a compelling model for 3' splice site recognition of long introns, which represent 80% of all human introns.
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Affiliation(s)
| | - Clara Hipp
- Institute of Structural Biology, Helmholtz Center Munich, 85764 Neuherberg, Germany; Bavarian NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, 85747 Garching, Germany
| | - Miriam M Mulorz
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | | | - Dalmira Hubrich
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | - Hyun-Seo Kang
- Institute of Structural Biology, Helmholtz Center Munich, 85764 Neuherberg, Germany; Bavarian NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, 85747 Garching, Germany
| | - Santiago Martínez-Lumbreras
- Institute of Structural Biology, Helmholtz Center Munich, 85764 Neuherberg, Germany; Bavarian NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, 85747 Garching, Germany
| | - Panajot Kristofori
- Department of Systems Biology, Institute for Biomedical Genetics (IBMG), University of Stuttgart, 70569 Stuttgart, Germany
| | | | | | - Jonas Schönfeld
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | - Cem Bakisoglu
- Buchmann Institute for Molecular Life Sciences & Institute of Molecular Biosciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - Anke Busch
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | - Heike Hänel
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | - Kerstin Tretow
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | - Mareen Welzel
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | | | - Martin M Möckel
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany
| | - Kathi Zarnack
- Buchmann Institute for Molecular Life Sciences & Institute of Molecular Biosciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany; CardioPulmonary Institute (CPI), 35392 Gießen, Germany
| | - Ingo Ebersberger
- Applied Bioinformatics Group, Institute of Cell Biology and Neuroscience, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany; Senckenberg Biodiversity and Climate Research Center (S-BIK-F), 60325 Frankfurt am Main, Germany; LOEWE Center for Translational Biodiversity Genomics (TBG), 60325 Frankfurt am Main, Germany
| | - Stefan Legewie
- Department of Systems Biology, Institute for Biomedical Genetics (IBMG), University of Stuttgart, 70569 Stuttgart, Germany; Stuttgart Research Center for Systems Biology (SRCSB), University of Stuttgart, 70569 Stuttgart, Germany
| | - Katja Luck
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany.
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Center Munich, 85764 Neuherberg, Germany; Bavarian NMR Center, Department of Bioscience, School of Natural Sciences, Technical University of Munich, 85747 Garching, Germany.
| | - Julian König
- Institute of Molecular Biology (IMB) gGmbH, 55128 Mainz, Germany.
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Izhaki-Tavor LS, Yechezkel IG, Alter J, Dessau M. RNA Encapsulation Mode and Evolutionary Insights from the Crystal Structure of Emaravirus Nucleoprotein. Microbiol Spectr 2023; 11:e0501822. [PMID: 37039649 PMCID: PMC10269810 DOI: 10.1128/spectrum.05018-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/27/2023] [Indexed: 04/12/2023] Open
Abstract
Enveloped RNA viruses are rare among plant viruses. Fimoviridae is a newly founded family of plant viruses within the Bunyavirales order that inflicts diverse crop losses worldwide. The fig mosaic virus (FMV), the representative member of the Fimoviridae family, was shown to be a causative agent for the fig mosaic disease. Like all bunyaviruses, FMV has a segmented, negative-sense, single-stranded RNA (ssRNA) genome that is encapsulated by the viral nucleoprotein (N). Here, we present high-resolution crystal structures of FMV N in its RNA-free and RNA-bound forms, revealing a "paper fortune teller" structural transition between the two states. The tightly packed tetramer of FNV N is similar to the structures of other N proteins of different members of the Bunyavirales order. In its RNA-bound form, the tetramer reorganizes to adopt a more open state that allows the accommodation of the RNA. Despite the low sequence similarity to N proteins of animal-infecting bunyaviruses, there is a striking structural resemblance between FMV N and nucleoproteins from members of the Peribunyaviridae, an animal-infecting family of viruses. This structural homology implies that enveloped plant viruses and animal-infecting viruses might have a common ancestor from which they diverged. IMPORTANCE Most insect-born viruses circulate within the Animalia kingdom, whereas plant-infecting RNA viruses are cross-kingdom pathogens. Many plant-infecting viruses cause devastating crop damage that leads to food security endangerment. The evolutionary crossroads of interkingdom circulation and infection are poorly understood. Thus, we took the structural approach to understand the similarities and differences between interkingdom-infecting viruses and viruses that circulate within one kingdom of life. Using our structures of FMV N in its free form and in complex with a single-stranded RNA (ssRNA), we dissected the mechanism by which FMV N binds to the RNA and revealed the conformational changes associated with the binding. The resemblance of our structure to N proteins from members of the Peribunyaviridae family and their recently published ribonucleoprotein (RNP) pseudoatomic resolution assembly model suggests that the FMV genome is similarly encapsulated. Thus, our finding unveils yet another bridge by which plant- and animal-infecting viruses are interconnected.
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Affiliation(s)
- Lee S. Izhaki-Tavor
- Azrieli Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel
| | - Itai G. Yechezkel
- Azrieli Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel
| | - Joel Alter
- Azrieli Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel
| | - Moshe Dessau
- Azrieli Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel
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Nandavaram A, Nandakumar A, Kashif GM, Sagar AL, Shailaja G, Ramesh A, Siddavattam D. Unusual Relationship between Iron Deprivation and Organophosphate Hydrolase Expression. Appl Environ Microbiol 2023; 89:e0190322. [PMID: 37074175 PMCID: PMC10231211 DOI: 10.1128/aem.01903-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/08/2023] [Indexed: 04/20/2023] Open
Abstract
Organophosphate hydrolases (OPH), hitherto known to hydrolyze the third ester bond of organophosphate (OP) insecticides and nerve agents, have recently been shown to interact with outer membrane transport components, namely, TonB and ExbB/ExbD. In an OPH negative background, Sphingopyxis wildii cells failed to transport ferric enterobactin and showed retarded growth under iron-limiting conditions. We now show the OPH-encoding organophosphate degradation (opd) gene from Sphingobium fuliginis ATCC 27551 to be part of the iron regulon. A fur-box motif found to be overlapping with the transcription start site (TSS) of the opd gene coordinates with an iron responsive element (IRE) RNA motif identified in the 5' coding region of the opd mRNA to tightly regulate opd gene expression. The fur-box motif serves as a target for the Fur repressor in the presence of iron. A decrease in iron concentration leads to the derepression of opd. IRE RNA inhibits the translation of opd mRNA and serves as a target for apo-aconitase (IRP). The IRP recruited by the IRE RNA abrogates IRE-mediated translational inhibition. Our findings establish a novel, multilayered, iron-responsive regulation that is crucial for OPH function in the transport of siderophore-mediated iron uptake. IMPORTANCE Sphingobium fuliginis, a soil-dwelling microbe isolated from agricultural soils, was shown to degrade a variety of insecticides and pesticides. These synthetic chemicals function as potent neurotoxins, and they belong to a class of chemicals termed organophosphates. S. fuliginis codes for OPH, an enzyme that has been shown to be involved in the metabolism of several organophosphates and their derivatives. Interestingly, OPH has also been shown to facilitate siderophore-mediated iron uptake in S. fuliginis and in another Sphingomonad, namely, Sphingopyxis wildii, implying that this organophosphate-metabolizing protein has a role in iron homeostasis, as well. Our research dissects the underlying molecular mechanisms linking iron to the expression of OPH, prompting a reconsideration of the role of OPH in Sphingomonads and a reevaluation of the evolutionary origins of the OPH proteins from soil bacteria.
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Affiliation(s)
- Aparna Nandavaram
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Anirudh Nandakumar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bengaluru, India
- The University of Trans-Disciplinary Health Sciences & Technology (TDU), Bengaluru, Karnataka, India
| | - G. M. Kashif
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | | | - G. Shailaja
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Arati Ramesh
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bengaluru, India
| | - Dayananda Siddavattam
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
- Department of Biochemistry, School of Sciences, GITAM University, Visakhapatnam, India
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9
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Nadal M, Anton R, Dorca‐Arévalo J, Estébanez‐Perpiñá E, Tizzano EF, Fuentes‐Prior P. Structure and function analysis of Sam68 and hnRNP A1 synergy in the exclusion of exon 7 from SMN2 transcripts. Protein Sci 2023; 32:e4553. [PMID: 36560896 PMCID: PMC10031812 DOI: 10.1002/pro.4553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 12/13/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022]
Abstract
Spinal muscular atrophy (SMA) is a neurodegenerative disease caused by the absence of a functional copy of the Survival of Motor Neuron 1 gene (SMN1). The nearly identical paralog, SMN2, cannot compensate for the loss of SMN1 because exon 7 is aberrantly skipped from most SMN2 transcripts, a process mediated by synergistic activities of Src-associated during mitosis, 68 kDa (Sam68/KHDRBS1) and heterogeneous nuclear ribonucleoprotein (hnRNP) A1. This results in the production of a truncated, nonfunctional protein that is rapidly degraded. Here, we present several crystal structures of Sam68 RNA-binding domain (RBD). Sam68-RBD forms stable symmetric homodimers by antiparallel association of helices α3 from two monomers. However, the details of domain organization and the dimerization interface differ significantly from previously characterized homologs. We demonstrate that Sam68 and hnRNP A1 can simultaneously bind proximal motifs within the central region of SMN2 (ex7). Furthermore, we show that the RNA-binding pockets of the two proteins are close to each other in their heterodimeric complex and identify contact residues using crosslinking-mass spectrometry. We present a model of the ternary Sam68·SMN2 (ex7)·hnRNP A1 complex that reconciles all available information on SMN1/2 splicing. Our findings have important implications for the etiology of SMA and open new avenues for the design of novel therapeutics to treat splicing diseases.
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Affiliation(s)
- Marta Nadal
- Molecular Bases of DiseaseBiomedical Research Institute Sant Pau (IIB Sant Pau)BarcelonaSpain
| | - Rosa Anton
- Molecular Bases of DiseaseBiomedical Research Institute Sant Pau (IIB Sant Pau)BarcelonaSpain
| | - Jonatan Dorca‐Arévalo
- Molecular Bases of DiseaseBiomedical Research Institute Sant Pau (IIB Sant Pau)BarcelonaSpain
- Present address:
Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Campus of BellvitgeHospitalet de Llobregat, University of BarcelonaBarcelonaSpain
| | - Eva Estébanez‐Perpiñá
- Structural Biology of Nuclear Receptors, Department of Biochemistry and Molecular Biomedicine, Faculty of BiologyInstitute of Biomedicine (IBUB) of the University of Barcelona (UB)BarcelonaSpain
| | - Eduardo F. Tizzano
- Medicine Genetics GroupVall d'Hebron Research Institute (VHIR)BarcelonaSpain
- Department of Clinical and Molecular GeneticsHospital Vall d'HebronBarcelonaSpain
| | - Pablo Fuentes‐Prior
- Molecular Bases of DiseaseBiomedical Research Institute Sant Pau (IIB Sant Pau)BarcelonaSpain
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10
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Steinmetz B, Smok I, Bikaki M, Leitner A. Protein-RNA interactions: from mass spectrometry to drug discovery. Essays Biochem 2023:EBC20220177. [PMID: 36866608 DOI: 10.1042/EBC20220177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 01/25/2023] [Accepted: 01/26/2023] [Indexed: 03/04/2023]
Abstract
Proteins and RNAs are fundamental parts of biological systems, and their interactions affect many essential cellular processes. Therefore, it is crucial to understand at a molecular and at a systems level how proteins and RNAs form complexes and mutually affect their functions. In the present mini-review, we will first provide an overview of different mass spectrometry (MS)-based methods to study the RNA-binding proteome (RBPome), most of which are based on photochemical cross-linking. As we will show, some of these methods are also able to provide higher-resolution information about binding sites, which are important for the structural characterisation of protein-RNA interactions. In addition, classical structural biology techniques such as nuclear magnetic resonance (NMR) spectroscopy and biophysical methods such as electron paramagnetic resonance (EPR) spectroscopy and fluorescence-based methods contribute to a detailed understanding of the interactions between these two classes of biomolecules. We will discuss the relevance of such interactions in the context of the formation of membrane-less organelles (MLOs) by liquid-liquid phase separation (LLPS) processes and their emerging importance as targets for drug discovery.
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11
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Laghmach R, Malhotra I, Potoyan DA. Multiscale Modeling of Protein-RNA Condensation in and Out of Equilibrium. Methods Mol Biol 2023; 2563:117-133. [PMID: 36227470 DOI: 10.1007/978-1-0716-2663-4_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
A vast number of intracellular membraneless bodies also known as biomolecular condensates form through a liquid-liquid phase separation (LLPS) of biomolecules. To date, phase separation has been identified as the main driving force for a membraneless organelles such as nucleoli, Cajal bodies, stress granules, and chromatin compartments. Recently, the protein-RNA condensation is receiving increased attention, because it is closely related to the biological function of cells such as transcription, translation, and RNA metabolism. Despite the multidisciplinary efforts put forth to study the biophysical properties of protein-RNA condensates, there are many fundamental unanswered questions regarding the mechanism of formation and regulation of protein-RNA condensates in eukaryotic cells. Major challenges in studying protein-RNA condensation stem from (i) the molecular heterogeneity and conformational flexibility of RNA and protein chains and (ii) the nonequilibrium nature of transcription and cellular environment. Computer simulations, bioinformatics, and mathematical models are uniquely positioned for shedding light on the microscopic nature of protein-RNA phase separation. To this end, there is an urgent need for innovative models with the right spatiotemporal resolution for confronting the experimental observables in a comprehensive and physics-based manner. In this chapter, we will summarize the currently emerging research efforts, which employ atomistic and coarse-grained molecular models and field theoretical models to understand equilibrium and nonequilibrium aspects of protein-RNA condensation.
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Affiliation(s)
- Rabia Laghmach
- Department of Chemistry, Iowa State University, Ames, IA, USA
| | - Isha Malhotra
- Department of Chemistry, Iowa State University, Ames, IA, USA
| | - Davit A Potoyan
- Department of Chemistry, Iowa State University, Ames, IA, USA.
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12
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Giambruno R, Nicassio F. Proximity-dependent biotinylation technologies for mapping RNA-protein interactions in live cells. Front Mol Biosci 2022; 9:1062448. [PMID: 36452457 PMCID: PMC9702341 DOI: 10.3389/fmolb.2022.1062448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 10/25/2022] [Indexed: 12/01/2023] Open
Abstract
Proximity ligation technologies are extremely powerful tools for unveiling RNA-protein interactions occurring at different stages in living cells. These approaches mainly rely on the inducible activity of enzymes (biotin ligases or peroxidases) that promiscuously biotinylate macromolecules within a 20 nm range. These enzymes can be either fused to an RNA binding protein or tethered to any RNA of interest and expressed in living cells to biotinylate the amino acids and nucleic acids of binding partners in proximity. The biotinylated molecules can then be easily affinity purified under denaturing conditions and analyzed by mass spectrometry or next generation sequencing. These approaches have been widely used in recent years, providing a potent instrument to map the molecular interactions of specific RNA-binding proteins as well as RNA transcripts occurring in mammalian cells. In addition, they permit the identification of transient interactions as well as interactions among low expressed molecules that are often missed by standard affinity purification strategies. This review will provide a brief overview of the currently available proximity ligation methods, highlighting both their strengths and shortcomings. Furthermore, it will bring further insights to the way these technologies could be further used to characterize post-transcriptional modifications that are known to regulate RNA-protein interactions.
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Affiliation(s)
- Roberto Giambruno
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, Milano, Italy
- Institute of Biomedical Technologies, National Research Council, Segrate, Italy
| | - Francesco Nicassio
- Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia, Milano, Italy
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13
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Shema Mugisha C, Dinh T, Kumar A, Tenneti K, Eschbach JE, Davis K, Gifford R, Kvaratskhelia M, Kutluay SB. Emergence of Compensatory Mutations Reveals the Importance of Electrostatic Interactions between HIV-1 Integrase and Genomic RNA. mBio 2022; 13:e0043122. [PMID: 35975921 PMCID: PMC9601147 DOI: 10.1128/mbio.00431-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 07/27/2022] [Indexed: 01/11/2023] Open
Abstract
HIV-1 integrase (IN) has a noncatalytic function in virion maturation through its binding to the viral RNA genome (gRNA). Class II IN substitutions inhibit IN-gRNA binding and result in the formation of virions with aberrant morphologies marked by mislocalization of the gRNA between the capsid lattice and the lipid envelope. These viruses are noninfectious due to a block at an early reverse transcription stage in target cells. HIV-1 IN utilizes basic residues within its C-terminal domain (CTD) to bind to the gRNA; however, the molecular nature of how these residues mediate gRNA binding and whether other regions of IN are involved remain unknown. To address this, we have isolated compensatory substitutions in the background of a class II IN mutant virus bearing R269A/K273A substitutions within the IN-CTD. We found that the nearby D256N and D270N compensatory substitutions restored the ability of IN to bind gRNA and led to the formation of mature infectious virions. Reinstating the local positive charge of the IN-CTD through individual D256R, D256K, D278R, and D279R substitutions was sufficient to specifically restore IN-gRNA binding and reverse transcription for the IN R269A/K273A as well as the IN R262A/R263A class II mutants. Structural modeling suggested that compensatory substitutions in the D256 residue created an additional interaction interface for gRNA binding, whereas other substitutions acted locally within the unstructured C-terminal tail of IN. Taken together, our findings highlight the essential role of CTD in gRNA binding and reveal the importance of pliable electrostatic interactions between the IN-CTD and the gRNA. IMPORTANCE In addition to its catalytic function, HIV-1 integrase (IN) binds to the viral RNA genome (gRNA) through positively charged residues (i.e., R262, R263, R269, K273) within its C-terminal domain (CTD) and regulates proper virion maturation. Mutation of these residues results in the formation of morphologically aberrant viruses blocked at an early reverse transcription stage in cells. Here we show that compensatory substitutions in nearby negatively charged aspartic acid residues (i.e., D256N, D270N) restore the ability of IN to bind gRNA for these mutant viruses and result in the formation of accurately matured infectious virions. Similarly, individual charge reversal substitutions at D256 as well as other nearby positions (i.e., D278, D279) are all sufficient to enable the respective IN mutants to bind gRNA, and subsequently restore reverse transcription and virion infectivity. Taken together, our findings reveal the importance of highly pliable electrostatic interactions in IN-gRNA binding.
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Affiliation(s)
- Christian Shema Mugisha
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Tung Dinh
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Abhishek Kumar
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Kasyap Tenneti
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Jenna E. Eschbach
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Keanu Davis
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Robert Gifford
- MRC-University of Glasgow Centre for Virus Research, Bearsden, Glasgow, United Kingdom
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Sebla B. Kutluay
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
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14
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Sarnowski CP, Bikaki M, Leitner A. Cross-linking and mass spectrometry as a tool for studying the structural biology of ribonucleoproteins. Structure 2022; 30:441-461. [PMID: 35366400 DOI: 10.1016/j.str.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 02/03/2022] [Accepted: 03/01/2022] [Indexed: 11/17/2022]
Abstract
Cross-linking and mass spectrometry (XL-MS) workflows represent an increasingly popular technique for low-resolution structural studies of macromolecular complexes. Cross-linking reactions take place in the solution state, capturing contact sites between components of a complex that represent the native, functionally relevant structure. Protein-protein XL-MS protocols are widely adopted, providing precise localization of cross-linking sites to single amino acid positions within a pair of cross-linked peptides. In contrast, protein-RNA XL-MS workflows are evolving rapidly and differ in their ability to localize interaction regions within the RNA sequence. Here, we review protein-protein and protein-RNA XL-MS workflows, and discuss their applications in studies of protein-RNA complexes. The examples highlight the complementary value of XL-MS in structural studies of protein-RNA complexes, where more established high-resolution techniques might be unable to produce conclusive data.
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Affiliation(s)
- Chris P Sarnowski
- Institute of Molecular Systems Biology, Department of Biology, ETH Zürich, 8093 Zurich, Switzerland; Systems Biology PhD Program, University of Zürich and ETH Zürich, Zurich, Switzerland
| | - Maria Bikaki
- Institute of Molecular Systems Biology, Department of Biology, ETH Zürich, 8093 Zurich, Switzerland
| | - Alexander Leitner
- Institute of Molecular Systems Biology, Department of Biology, ETH Zürich, 8093 Zurich, Switzerland.
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15
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Zhao B, Katuwawala A, Oldfield CJ, Hu G, Wu Z, Uversky VN, Kurgan L. Intrinsic Disorder in Human RNA-Binding Proteins. J Mol Biol 2021; 433:167229. [PMID: 34487791 DOI: 10.1016/j.jmb.2021.167229] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 12/24/2022]
Abstract
Although RNA-binding proteins (RBPs) are known to be enriched in intrinsic disorder, no previous analysis focused on RBPs interacting with specific RNA types. We fill this gap with a comprehensive analysis of the putative disorder in RBPs binding to six common RNA types: messenger RNA (mRNA), transfer RNA (tRNA), small nuclear RNA (snRNA), non-coding RNA (ncRNA), ribosomal RNA (rRNA), and internal ribosome RNA (irRNA). We also analyze the amount of putative intrinsic disorder in the RNA-binding domains (RBDs) and non-RNA-binding-domain regions (non-RBD regions). Consistent with previous studies, we show that in comparison with human proteome, RBPs are significantly enriched in disorder. However, closer examination finds significant enrichment in predicted disorder for the mRNA-, rRNA- and snRNA-binding proteins, while the proteins that interact with ncRNA and irRNA are not enriched in disorder, and the tRNA-binding proteins are significantly depleted in disorder. We show a consistent pattern of significant disorder enrichment in the non-RBD regions coupled with low levels of disorder in RBDs, which suggests that disorder is relatively rarely utilized in the RNA-binding regions. Our analysis of the non-RBD regions suggests that disorder harbors posttranslational modification sites and is involved in the putative interactions with DNA. Importantly, we utilize experimental data from DisProt and independent data from Pfam to validate the above observations that rely on the disorder predictions. This study provides new insights into the distribution of disorder across proteins that bind different RNA types and the functional role of disorder in the regions where it is enriched.
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Affiliation(s)
- Bi Zhao
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Akila Katuwawala
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Christopher J Oldfield
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Gang Hu
- School of Statistics and Data Science, LPMC and KLMDASR, Nankai University, Tianjin 300071, China
| | - Zhonghua Wu
- School of Mathematical Sciences and LPMC, Nankai University, Tianjin 300071, China
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Lukasz Kurgan
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA 23284, USA.
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16
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Gumna J, Andrzejewska-Romanowska A, Garfinkel DJ, Pachulska-Wieczorek K. RNA Binding Properties of the Ty1 LTR-Retrotransposon Gag Protein. Int J Mol Sci 2021; 22:ijms22169103. [PMID: 34445809 PMCID: PMC8396678 DOI: 10.3390/ijms22169103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 08/21/2021] [Accepted: 08/22/2021] [Indexed: 11/16/2022] Open
Abstract
A universal feature of retroelement propagation is the formation of distinct nucleoprotein complexes mediated by the Gag capsid protein. The Ty1 retrotransposon Gag protein from Saccharomyces cerevisiae lacks sequence homology with retroviral Gag, but is functionally related. In addition to capsid assembly functions, Ty1 Gag promotes Ty1 RNA dimerization and cyclization and initiation of reverse transcription. Direct interactions between Gag and retrotransposon genomic RNA (gRNA) are needed for Ty1 replication, and mutations in the RNA-binding domain disrupt nucleation of retrosomes and assembly of functional virus-like particles (VLPs). Unlike retroviral Gag, the specificity of Ty1 Gag-RNA interactions remain poorly understood. Here we use microscale thermophoresis (MST) and electrophoretic mobility shift assays (EMSA) to analyze interactions of immature and mature Ty1 Gag with RNAs. The salt-dependent experiments showed that Ty1 Gag binds with high and similar affinity to different RNAs. However, we observed a preferential interaction between Ty1 Gag and Ty1 RNA containing a packaging signal (Psi) in RNA competition analyses. We also uncover a relationship between Ty1 RNA structure and Gag binding involving the pseudoknot present on Ty1 gRNA. In all likelihood, the differences in Gag binding affinity detected in vitro only partially explain selective Ty1 RNA packaging into VLPs in vivo.
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Affiliation(s)
- Julita Gumna
- Department of Structure and Function of Retrotransposons, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland; (J.G.); (A.A.-R.)
| | - Angelika Andrzejewska-Romanowska
- Department of Structure and Function of Retrotransposons, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland; (J.G.); (A.A.-R.)
| | - David J. Garfinkel
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA;
| | - Katarzyna Pachulska-Wieczorek
- Department of Structure and Function of Retrotransposons, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland; (J.G.); (A.A.-R.)
- Correspondence: ; Tel.: +48-61-852-85-03; Fax: +48-61-852-05-32
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17
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Christopoulou N, Granneman S. The role of RNA-binding proteins in mediating adaptive responses in Gram-positive bacteria. FEBS J 2021; 289:1746-1764. [PMID: 33690958 DOI: 10.1111/febs.15810] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 02/06/2023]
Abstract
Bacteria are constantly subjected to stressful conditions, such as antibiotic exposure, nutrient limitation and oxidative stress. For pathogenic bacteria, adapting to the host environment, escaping defence mechanisms and coping with antibiotic stress are crucial for their survival and the establishment of a successful infection. Stress adaptation relies heavily on the rate at which the organism can remodel its gene expression programme to counteract the stress. RNA-binding proteins mediating co- and post-transcriptional regulation have recently emerged as important players in regulating gene expression during adaptive responses. Most of the research on these layers of gene expression regulation has been done in Gram-negative model organisms where, thanks to a wide variety of global studies, large post-transcriptional regulatory networks have been uncovered. Unfortunately, our understanding of post-transcriptional regulation in Gram-positive bacteria is lagging behind. One possible explanation for this is that many proteins employed by Gram-negative bacteria are not well conserved in Gram-positives. And even if they are conserved, they do not always play similar roles as in Gram-negative bacteria. This raises the important question whether Gram-positive bacteria regulate gene expression in a significantly different way. The goal of this review was to discuss this in more detail by reviewing the role of well-known RNA-binding proteins in Gram-positive bacteria and by highlighting their different behaviours with respect to some of their Gram-negative counterparts. Finally, the second part of this review introduces several unusual RNA-binding proteins of Gram-positive species that we believe could also play an important role in adaptive responses.
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Affiliation(s)
- Niki Christopoulou
- Centre for Synthetic and Systems Biology, School of Biological Sciences, University of Edinburgh, UK
| | - Sander Granneman
- Centre for Synthetic and Systems Biology, School of Biological Sciences, University of Edinburgh, UK
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18
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Karakostis K, López I, Peña-Balderas AM, Fåhareus R, Olivares-Illana V. Molecular and Biochemical Techniques for Deciphering p53-MDM2 Regulatory Mechanisms. Biomolecules 2020; 11:36. [PMID: 33396576 PMCID: PMC7824699 DOI: 10.3390/biom11010036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/12/2020] [Accepted: 12/14/2020] [Indexed: 12/12/2022] Open
Abstract
The p53 and Mouse double minute 2 (MDM2) proteins are hubs in extensive networks of interactions with multiple partners and functions. Intrinsically disordered regions help to adopt function-specific structural conformations in response to ligand binding and post-translational modifications. Different techniques have been used to dissect interactions of the p53-MDM2 pathway, in vitro, in vivo, and in situ each having its own advantages and disadvantages. This review uses the p53-MDM2 to show how different techniques can be employed, illustrating how a combination of in vitro and in vivo techniques is highly recommended to study the spatio-temporal location and dynamics of interactions, and to address their regulation mechanisms and functions. By using well-established techniques in combination with more recent advances, it is possible to rapidly decipher complex mechanisms, such as the p53 regulatory pathway, and to demonstrate how protein and nucleotide ligands in combination with post-translational modifications, result in inter-allosteric and intra-allosteric interactions that govern the activity of the protein complexes and their specific roles in oncogenesis. This promotes elegant therapeutic strategies that exploit protein dynamics to target specific interactions.
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Affiliation(s)
- Konstantinos Karakostis
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France; (K.K.); (R.F.)
| | - Ignacio López
- Biochemistry-Molecular Biology, Faculty of Science, Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay;
| | - Ana M. Peña-Balderas
- Laboratorio de Interacciones Biomoleculares y Cáncer, Instituto de Física Universidad Autónoma de San Luis Potosí, Manuel Nava 6, Zona Universitaria, San Luis Potosí 78290, Mexico;
| | - Robin Fåhareus
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France; (K.K.); (R.F.)
- Regional Centre for Applied Molecular Oncology (RECAMO), Masaryk Memorial Cancer Institute, Zluty Kopec 7, 65653 Brno, Czech Republic
- Department of Medical Biosciences, Building 6M, Umeå University, 90185 Umeå, Sweden
- International Center for Cancer Vaccine Science (ICCVS), University of Gdańsk, Science, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Vanesa Olivares-Illana
- Laboratorio de Interacciones Biomoleculares y Cáncer, Instituto de Física Universidad Autónoma de San Luis Potosí, Manuel Nava 6, Zona Universitaria, San Luis Potosí 78290, Mexico;
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19
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Wang K, Hu G, Wu Z, Su H, Yang J, Kurgan L. Comprehensive Survey and Comparative Assessment of RNA-Binding Residue Predictions with Analysis by RNA Type. Int J Mol Sci 2020; 21:E6879. [PMID: 32961749 PMCID: PMC7554811 DOI: 10.3390/ijms21186879] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 09/15/2020] [Accepted: 09/17/2020] [Indexed: 02/07/2023] Open
Abstract
With close to 30 sequence-based predictors of RNA-binding residues (RBRs), this comparative survey aims to help with understanding and selection of the appropriate tools. We discuss past reviews on this topic, survey a comprehensive collection of predictors, and comparatively assess six representative methods. We provide a novel and well-designed benchmark dataset and we are the first to report and compare protein-level and datasets-level results, and to contextualize performance to specific types of RNAs. The methods considered here are well-cited and rely on machine learning algorithms on occasion combined with homology-based prediction. Empirical tests reveal that they provide relatively accurate predictions. Virtually all methods perform well for the proteins that interact with rRNAs, some generate accurate predictions for mRNAs, snRNA, SRP and IRES, while proteins that bind tRNAs are predicted poorly. Moreover, except for DRNApred, they confuse DNA and RNA-binding residues. None of the six methods consistently outperforms the others when tested on individual proteins. This variable and complementary protein-level performance suggests that users should not rely on applying just the single best dataset-level predictor. We recommend that future work should focus on the development of approaches that facilitate protein-level selection of accurate predictors and the consensus-based prediction of RBRs.
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Affiliation(s)
- Kui Wang
- School of Mathematical Sciences and LPMC, Nankai University, Tianjin 300071, China; (K.W.); (Z.W.); (H.S.); (J.Y.)
| | - Gang Hu
- School of Statistics and Data Science, LPMC and KLMDASR, Nankai University, Tianjin 300071, China;
| | - Zhonghua Wu
- School of Mathematical Sciences and LPMC, Nankai University, Tianjin 300071, China; (K.W.); (Z.W.); (H.S.); (J.Y.)
| | - Hong Su
- School of Mathematical Sciences and LPMC, Nankai University, Tianjin 300071, China; (K.W.); (Z.W.); (H.S.); (J.Y.)
| | - Jianyi Yang
- School of Mathematical Sciences and LPMC, Nankai University, Tianjin 300071, China; (K.W.); (Z.W.); (H.S.); (J.Y.)
| | - Lukasz Kurgan
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA 23284, USA
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20
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Iosub IA, van Nues RW, McKellar SW, Nieken KJ, Marchioretto M, Sy B, Tree JJ, Viero G, Granneman S. Hfq CLASH uncovers sRNA-target interaction networks linked to nutrient availability adaptation. eLife 2020; 9:54655. [PMID: 32356726 PMCID: PMC7213987 DOI: 10.7554/elife.54655] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 04/30/2020] [Indexed: 01/10/2023] Open
Abstract
By shaping gene expression profiles, small RNAs (sRNAs) enable bacteria to efficiently adapt to changes in their environment. To better understand how Escherichia coli acclimatizes to nutrient availability, we performed UV cross-linking, ligation and sequencing of hybrids (CLASH) to uncover Hfq-associated RNA-RNA interactions at specific growth stages. We demonstrate that Hfq CLASH robustly captures bona fide RNA-RNA interactions. We identified hundreds of novel sRNA base-pairing interactions, including many sRNA-sRNA interactions and involving 3’UTR-derived sRNAs. We rediscovered known and identified novel sRNA seed sequences. The sRNA-mRNA interactions identified by CLASH have strong base-pairing potential and are highly enriched for complementary sequence motifs, even those supported by only a few reads. Yet, steady state levels of most mRNA targets were not significantly affected upon over-expression of the sRNA regulator. Our results reinforce the idea that the reproducibility of the interaction, not base-pairing potential, is a stronger predictor for a regulatory outcome.
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Affiliation(s)
- Ira Alexandra Iosub
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Stuart William McKellar
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Karen Jule Nieken
- Institute of Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Brandon Sy
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Jai Justin Tree
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | | | - Sander Granneman
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, United Kingdom
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21
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Singh D, Murashko ON, Lin-Chao S. Posttranscriptional Regulation of tnaA by Protein-RNA Interaction Mediated by Ribosomal Protein L4 in Escherichia coli. J Bacteriol 2020; 202:e00799-19. [PMID: 32123036 DOI: 10.1128/JB.00799-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 02/13/2020] [Indexed: 11/26/2022] Open
Abstract
Some ribosomal proteins have extraribosomal functions in addition to ribosome translation function. The extraribosomal functions of several r-proteins control operon expression by binding to own-operon transcripts. Previously, we discovered a posttranscriptional, RNase E-dependent regulatory role for r-protein L4 in the stabilization of stress-responsive transcripts. Here, we found an additional extraribosomal function for L4 in regulating the tna operon by L4-intergenic spacer mRNA interactions. L4 binds to the transcribed spacer RNA between tnaC and tnaA and alters the structural conformation of the spacer RNA, thereby reducing the translation of TnaA. Our study establishes a previously unknown L4-mediated mechanism for regulating gene expression, suggesting that bacterial cells have multiple strategies for controlling levels of tryptophanase in response to varied cell growth conditions. Escherichia coli ribosomal protein (r-protein) L4 has extraribosomal biological functions. Previously, we described L4 as inhibiting RNase E activity through protein-protein interactions. Here, we report that from stabilized transcripts regulated by L4-RNase E, mRNA levels of tnaA (encoding tryptophanase from the tnaCAB operon) increased upon ectopic L4 expression, whereas TnaA protein levels decreased. However, at nonpermissive temperatures (to inactivate RNase E), tnaA mRNA and protein levels both increased in an rne temperature-sensitive [rne(Ts)] mutant strain. Thus, L4 protein fine-tunes TnaA protein levels independently of its inhibition of RNase E. We demonstrate that ectopically expressed L4 binds with transcribed spacer RNA between tnaC and tnaA and downregulates TnaA translation. We found that deletion of the 5′ or 3′ half of the spacer compared to the wild type resulted in a similar reduction in TnaA translation in the presence of L4. In vitro binding of L4 to the tnaC-tnaA transcribed spacer RNA results in changes to its secondary structure. We reveal that during early stationary-phase bacterial growth, steady-state levels of tnaA mRNA increased but TnaA protein levels decreased. We further confirm that endogenous L4 binds to tnaC-tnaA transcribed spacer RNA in cells at early stationary phase. Our results reveal the novel function of L4 in fine-tuning TnaA protein levels during cell growth and demonstrate that r-protein L4 acts as a translation regulator outside the ribosome and its own operon. IMPORTANCE Some ribosomal proteins have extraribosomal functions in addition to ribosome translation function. The extraribosomal functions of several r-proteins control operon expression by binding to own-operon transcripts. Previously, we discovered a posttranscriptional, RNase E-dependent regulatory role for r-protein L4 in the stabilization of stress-responsive transcripts. Here, we found an additional extraribosomal function for L4 in regulating the tna operon by L4-intergenic spacer mRNA interactions. L4 binds to the transcribed spacer RNA between tnaC and tnaA and alters the structural conformation of the spacer RNA, thereby reducing the translation of TnaA. Our study establishes a previously unknown L4-mediated mechanism for regulating gene expression, suggesting that bacterial cells have multiple strategies for controlling levels of tryptophanase in response to varied cell growth conditions.
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22
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Ban Y, Tan P, Cai J, Li J, Hu M, Zhou Y, Mei Y, Tan Y, Li X, Zeng Z, Xiong W, Li G, Li X, Yi M, Xiang B. LNCAROD is stabilized by m6A methylation and promotes cancer progression via forming a ternary complex with HSPA1A and YBX1 in head and neck squamous cell carcinoma. Mol Oncol 2020; 14:1282-1296. [PMID: 32216017 PMCID: PMC7266281 DOI: 10.1002/1878-0261.12676] [Citation(s) in RCA: 116] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/02/2020] [Accepted: 03/18/2020] [Indexed: 12/24/2022] Open
Abstract
Head and neck squamous cell carcinoma (HNSCC) constitute approximately 4% of all cancers worldwide. In this study, we analyzed the expression profile of the long noncoding RNA (lncRNA) of 502 HNSCC patients from The Cancer Genome Atlas database. Among the differentially expressed lncRNAs between HNSCC and normal samples, LNCAROD is overexpressed in HNSCC and associated with advanced T stage and shortened overall survival. The N6‐methyladenosine (m6A) modification mediated by METTL3 and METTL14 enhanced the stability of LNCAROD in HNSCC cells. Depletion of LNCAROD attenuated cell proliferation, mobility in vitro, and tumorigenicity in vivo, whereas overexpression of LNCAROD exerted opposite effects. LNCAROD is mainly distributed in nucleus and binds with YBX1 and HSPA1A proteins. Silencing either YBX1 or HSPA1A did not affect the level of LNCAROD. However, loss of LNCAROD led to shortened half‐life of YBX1 protein. Mechanistically, LNCAROD protected YBX1 from proteasomal degradation by facilitating YBX1‐HSPA1A protein–protein interaction. Depletion of HSPA1A in LNCAROD‐overexpressing cells resulted in accelerated proteasomal degradation of YBX1 protein. Moreover, re‐expression of Flag‐YBX1 in LNCAROD‐silenced cells rescued malignant behavior of HNSCC cells. Our study indicates that LNCAROD is an oncogenic lncRNA and dysregulation of m6A modification might account for aberrant expression of LNCAROD in HNSCC. LNCAROD acts as a scaffold for the interaction between YBX1 and HSPA1A, preventing proteasomal degradation of YBX1 in HNSCC cells.
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Affiliation(s)
- Yuanyuan Ban
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Pingqing Tan
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Jing Cai
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Junjun Li
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Meng Hu
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Ying Zhou
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Yan Mei
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Yixin Tan
- Department of Dermatology, The Second Xiangya Hospital, The Central South University, Changsha, China
| | - Xiaoling Li
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Zhaoyang Zeng
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Wei Xiong
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Guiyuan Li
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
| | - Xiayu Li
- Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Mei Yi
- The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China.,Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China
| | - Bo Xiang
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.,Hunan Key Laboratory of Nonresolving Inflammation and Cancer, The Third Xiangya Hospital, Central South University, Changsha, China.,The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute and School of Basic Medical Sciences, Central South University, Changsha, China
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23
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Misra C, Bangru S, Lin F, Lam K, Koenig SN, Lubbers ER, Hedhli J, Murphy NP, Parker DJ, Dobrucki LW, Cooper TA, Tajkhorshid E, Mohler PJ, Kalsotra A. Aberrant Expression of a Non-muscle RBFOX2 Isoform Triggers Cardiac Conduction Defects in Myotonic Dystrophy. Dev Cell 2020; 52:748-763.e6. [PMID: 32109384 PMCID: PMC7098852 DOI: 10.1016/j.devcel.2020.01.037] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 11/25/2019] [Accepted: 01/29/2020] [Indexed: 12/20/2022]
Abstract
Myotonic dystrophy type 1 (DM1) is a multisystemic genetic disorder caused by the CTG repeat expansion in the 3'-untranslated region of DMPK gene. Heart dysfunctions occur in ∼80% of DM1 patients and are the second leading cause of DM1-related deaths. Herein, we report that upregulation of a non-muscle splice isoform of RNA-binding protein RBFOX2 in DM1 heart tissue-due to altered splicing factor and microRNA activities-induces cardiac conduction defects in DM1 individuals. Mice engineered to express the non-muscle RBFOX240 isoform in heart via tetracycline-inducible transgenesis, or CRISPR/Cas9-mediated genome editing, reproduced DM1-related cardiac conduction delay and spontaneous episodes of arrhythmia. Further, by integrating RNA binding with cardiac transcriptome datasets from DM1 patients and mice expressing the non-muscle RBFOX2 isoform, we identified RBFOX240-driven splicing defects in voltage-gated sodium and potassium channels, which alter their electrophysiological properties. Thus, our results uncover a trans-dominant role for an aberrantly expressed RBFOX240 isoform in DM1 cardiac pathogenesis.
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Affiliation(s)
- Chaitali Misra
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Sushant Bangru
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Cancer Center at Illinois, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Feikai Lin
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Kin Lam
- Department of Physics, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Centers for Macromolecular Modeling, Bioinformatics and Experimental Molecular Imaging at Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Sara N Koenig
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, USA
| | - Ellen R Lubbers
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, USA
| | - Jamila Hedhli
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Centers for Macromolecular Modeling, Bioinformatics and Experimental Molecular Imaging at Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Nathaniel P Murphy
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, USA
| | - Darren J Parker
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Lawrence W Dobrucki
- Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Centers for Macromolecular Modeling, Bioinformatics and Experimental Molecular Imaging at Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Cancer Center at Illinois, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Thomas A Cooper
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
| | - Emad Tajkhorshid
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Department of Physics, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Department of Bioengineering, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Centers for Macromolecular Modeling, Bioinformatics and Experimental Molecular Imaging at Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Cancer Center at Illinois, University of Illinois, Urbana-Champaign, Urbana, IL, USA
| | - Peter J Mohler
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, USA
| | - Auinash Kalsotra
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana-Champaign, Urbana, IL, USA; Cancer Center at Illinois, University of Illinois, Urbana-Champaign, Urbana, IL, USA.
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24
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Suman, Chaudhary M, Nain V. In silico identification and evaluation of Bacillus subtilis cold shock protein B (cspB)-like plant RNA chaperones. J Biomol Struct Dyn 2020; 39:841-850. [PMID: 31959085 DOI: 10.1080/07391102.2020.1719198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cold shock domain (CSD) proteins with nucleic acid binding properties are well conserved from bacteria to higher organisms. In bacteria, the cold shock proteins (CSPs) are single domain RNA chaperones, whereas in animals and plants, CSDs are accompanied by additional domains with roles in transcription regulation. Bacterial CSPs (Escherischia coli-cspA and Bacilus subtilis-cspB) have successfully imparted drought tolerance in transgenic plants; however, these cannot be deployed in food crops due to their low public acceptance of transgenics with bacterial genes. Therefore, this study aimed to identify CSPB-like proteins from plants that can be used for developing drought tolerant transgenic crops. Twelve single domain plant CSPs presenting >40% sequence identity with CSPB were identified. All 12 plant CSPs were modeled by homology modeling and refined by molecular dynamics simulation for 10 ns. Selected plant CSPs and CSPB exhibited high structural similarity (Tm-score: 0.63-0.86). Structure based phylogenetic analysis revealed that Triticum aestivum-csp1 and Aegilops tauschii-cspE are structurally closer to CSPB compared to their orthologs and paralogs. Molecular docking with three RNA molecules (5U, UC3U, and C2UC) indicates that Ricinus communis-csd1 and T. aestivum-csp1 have a binding pattern and docking scores similar to those of CSPB. Furthermore, MD simulations for 20 ns and analysis of RMSD, RMSF, Rg as well as the number of hydrogen bonds in all the three complexes revealed that plant CSP-RNA complexes behave in a similar manner to that of the CSPB-RNA complex, making them highly potential candidate genes for developing drought tolerance in transgenic plants. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Suman
- School of Biotechnology, Gautam Buddha University, Greater Noida, India
| | | | - Vikrant Nain
- School of Biotechnology, Gautam Buddha University, Greater Noida, India
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25
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Duss O, Stepanyuk GA, Puglisi JD, Williamson JR. Transient Protein-RNA Interactions Guide Nascent Ribosomal RNA Folding. Cell 2019; 179:1357-1369.e16. [PMID: 31761533 DOI: 10.1016/j.cell.2019.10.035] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/18/2019] [Accepted: 10/28/2019] [Indexed: 11/28/2022]
Abstract
Ribosome assembly is an efficient but complex and heterogeneous process during which ribosomal proteins assemble on the nascent rRNA during transcription. Understanding how the interplay between nascent RNA folding and protein binding determines the fate of transcripts remains a major challenge. Here, using single-molecule fluorescence microscopy, we follow assembly of the entire 3' domain of the bacterial small ribosomal subunit in real time. We find that co-transcriptional rRNA folding is complicated by the formation of long-range RNA interactions and that r-proteins self-chaperone the rRNA folding process prior to stable incorporation into a ribonucleoprotein (RNP) complex. Assembly is initiated by transient rather than stable protein binding, and the protein-RNA binding dynamics gradually decrease during assembly. This work questions the paradigm of strictly sequential and cooperative ribosome assembly and suggests that transient binding of RNA binding proteins to cellular RNAs could provide a general mechanism to shape nascent RNA folding during RNP assembly.
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Affiliation(s)
- Olivier Duss
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Galina A Stepanyuk
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Joseph D Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - James R Williamson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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26
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Byun WG, Lim D, Park SB. Discovery of Small-Molecule Modulators of Protein-RNA Interactions by Fluorescence Intensity-Based Binding Assay. Chembiochem 2019; 21:818-824. [PMID: 31587454 DOI: 10.1002/cbic.201900467] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 10/04/2019] [Indexed: 12/18/2022]
Abstract
Protein-RNA interactions mediate various cellular processes, the dysregulation of which has been associated with a list of diseases. Thus, novel experimental tools for monitoring protein-RNA interactions are highly desirable to identify new chemical modulators of these therapeutic targets. In this study, we constructed simple fluorescence intensity-based protein-RNA binding assays by testing multiple environment-sensitive organic fluorophores. We selected the oncogenic interaction between Lin28 and the let-7 microRNA and the important immunomodulatory Roquin-Tnf CDE interaction as representative targets. We adapted this assay to high-throughput screening for the identification of pyrazolyl thiazolidinedione-type molecules as potent small-molecule inhibitors of protein-microRNA interactions. We clearly showed the structure-activity relationships of this new class of Lin28-let-7 interaction inhibitors, and confirmed that cellular mature let-7 microRNAs and their target genes could be modulated upon treatment with the pyrazolyl thiazolidinedione-type inhibitor. We expect that our simple and adaptable screening approach can be applied for the development of various assay systems aimed at the identification of bioactive small molecules targeting protein-RNA interactions.
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Affiliation(s)
- Wan Gi Byun
- CRI Center for Chemical Proteomics, Department of Chemistry, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, South Korea
| | - Donghyun Lim
- Department of Biophysics and Chemical Biology, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, South Korea
| | - Seung Bum Park
- CRI Center for Chemical Proteomics, Department of Chemistry, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, South Korea.,Department of Biophysics and Chemical Biology, Seoul National University, 1 Gwanak-ro Gwanak-gu, Seoul, 08826, South Korea
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27
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Garriga-Canut M, Yang JS, Preusser F, Speroni S, Gili M, Maurer SP. rec-Y3H screening allows the detection of simultaneous RNA-protein interface mutations. Methods 2020; 178:19-32. [PMID: 31493518 DOI: 10.1016/j.ymeth.2019.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/16/2019] [Accepted: 09/01/2019] [Indexed: 12/20/2022] Open
Abstract
Understanding which proteins and RNAs directly interact is crucial for revealing cellular mechanisms of gene regulation. Efficient methods allowing to detect RNA-protein interactions and dissect the underlying molecular origin for RNA-binding protein (RBP) specificity are in high demand. The recently developed recombination-Y3H screening (rec-Y3H) enabled many-by-many detection of interactions between pools of proteins and RNA fragments for the first time. Here, we test different conditions for protein-RNA interaction selection during rec-Y3H screening and provide information on the screen performance in several selection media. We further show that rec-Y3H can detect the nucleotide and amino acid sequence determinants of protein-RNA interactions by mutating residues of interacting proteins and RNAs simultaneously. We envision that systematic RNA-protein interface mutation screening will be useful to understand the molecular origin of RBP selectivity and to engineer RBPs with targeted specificities in the future.
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28
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Jaremko D, Ciganda M, Christen L, Williams N. Trypanosoma brucei L11 Is Essential to Ribosome Biogenesis and Interacts with the Kinetoplastid-Specific Proteins P34 and P37. mSphere 2019; 4:e00475-19. [PMID: 31434747 DOI: 10.1128/mSphere.00475-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Eukaryotic ribosome biogenesis is an essential cellular process involving tightly coordinated assembly of multiple rRNA and protein components. Much of our understanding of this pathway has come from studies performed with yeast model systems. These studies have identified critical checkpoints in the maturation of the large ribosomal subunit (LSU/60S), one of which is the proper formation and incorporation of the 5S ribonucleoprotein complex (5S RNP). Research on the 5S RNP has identified a complex containing the four proteins L5, L11, Rpf2, and Rrs1 as well as 5S rRNA. Our laboratory has studied the 5S RNP in Trypanosoma brucei, a eukaryotic parasite, and identified the proteins P34 and P37 as essential, parasite-specific members of this complex. We have additionally identified homologues of L5, Rpf2, Rrs1, and 5S rRNA in T. brucei and characterized their roles in this essential process. In this study, we examined the T. brucei homologue of ribosomal protein L11 as a member of the 5S RNP. We showed that TbL11 is essential and that it is important for proper ribosome subunit formation and 60S rRNA processing. Additionally, we identified TbL11 interactions with TbL5 and TbRpf2, as well as novel interactions with the kinetoplast-specific proteins P34 and P37. These findings expand our understanding of a crucial process outside the context of model yeast organisms and highlight differences in an otherwise highly conserved process that could be used to develop future treatments against T. brucei IMPORTANCE The human-pathogenic, eukaryotic parasite Trypanosoma brucei causes human and animal African trypanosomiases. Treatments for T. brucei suffer from numerous hurdles, including adverse side effects and developing resistance. Ribosome biogenesis is one critical process for T. brucei survival that could be targeted for new drug development. A critical checkpoint in ribosome biogenesis is formation of the 5S RNP, which we have shown involves the trypanosome-specific proteins P34 and P37 as well as homologues of Rpf2, Rrs1, and L5. We have identified parasite-specific characteristics of these proteins and involvement in key parts of ribosome biogenesis, making them candidates for future drug development. In this work, we characterized the T. brucei homologue of ribosomal protein L11. We show that it is essential for parasite survival and is involved in ribosome biogenesis and rRNA processing. Furthermore, we identified novel interactions with P34 and P37, characteristics that make this protein a potential target for novel chemotherapeutics.
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Rink C, Williams N. Unique Interactions of the Nuclear Export Receptors TbMex67 and TbMtr2 with Components of the 5S Ribonuclear Particle in Trypanosoma brucei. mSphere 2019; 4:e00471-19. [PMID: 31413174 DOI: 10.1128/mSphere.00471-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Trypanosoma brucei is the causative agent for both African sleeping sickness in humans and nagana in cattle. Ribosome biogenesis in these pathogens requires both conserved and trypanosome-specific proteins to coordinate in a complex pathway. We have previously shown that the trypanosome-specific proteins P34/P37 are essential to the interaction of the TbNmd3-TbXpoI export complex with the 60S ribosomal subunits, allowing their translocation across the nuclear envelope. Our recent studies show that the trypanosome orthologues of the auxiliary export proteins TbMex67-TbMtr2 are required for ribosome assembly, proper rRNA processing, and polysome formation. Here we show that TbMex67-TbMtr2 interact with members of the 60S ribosomal subunit 5S RNP. Although TbMex67 has a unique structure among the Mex67 orthologues and forms unique interactions with the 5S RNP, particularly with trypanosome-specific P34/P37, it performs a conserved function in ribosome assembly. These unique structures and parasite-specific interactions may provide new therapeutic targets against this important parasite. Eukaryotic ribosome biogenesis is a complicated and highly conserved biological process. A critical step in ribosome biogenesis is the translocation of the immature ribosomal subunits from the nucleoplasm, across the nucleopore complex, to the cytoplasm where they undergo final maturation. Many nonribosomal proteins are needed to facilitate export of the ribosomal subunits, and one complex participating in export of the pre-60S in Saccharomyces cerevisiae is the heterodimer Mex67-Mtr2. In Trypanomsoma brucei, the process of ribosome biogenesis differs from the yeast process in key steps and is not yet fully characterized. However, our laboratory has previously identified the trypanosome-specific proteins P34/P37 and has shown that P34/P37 are necessary for the formation of the 5S ribonuclear particle (RNP) and for the nuclear export of the pre-60S subunit. We have also shown that loss of TbMex67 or TbMtr2 leads to aberrant ribosome formation, rRNA processing, and polysome formation in T. brucei. In this study, we characterize the interaction of TbMex67 and TbMtr2 with the components of the 5S RNP (P34/P37, L5 and 5S rRNA) of the 60S subunit. We demonstrate that TbMex67 directly interacts with P34 and L5 proteins as well as 5S rRNA, while TbMtr2 does not. Using protein sequence alignments and structure prediction modeling, we show that TbMex67 lacks the amino acids previously shown to be essential for binding to 5S rRNA in yeast and in general aligns more closely with the human orthologue (NXF1 or TAP). This work suggests that the T. brucei Mex67-Mtr2 binds ribosomal cargo differently from the yeast system. IMPORTANCETrypanosoma brucei is the causative agent for both African sleeping sickness in humans and nagana in cattle. Ribosome biogenesis in these pathogens requires both conserved and trypanosome-specific proteins to coordinate in a complex pathway. We have previously shown that the trypanosome-specific proteins P34/P37 are essential to the interaction of the TbNmd3-TbXpoI export complex with the 60S ribosomal subunits, allowing their translocation across the nuclear envelope. Our recent studies show that the trypanosome orthologues of the auxiliary export proteins TbMex67-TbMtr2 are required for ribosome assembly, proper rRNA processing, and polysome formation. Here we show that TbMex67-TbMtr2 interact with members of the 60S ribosomal subunit 5S RNP. Although TbMex67 has a unique structure among the Mex67 orthologues and forms unique interactions with the 5S RNP, particularly with trypanosome-specific P34/P37, it performs a conserved function in ribosome assembly. These unique structures and parasite-specific interactions may provide new therapeutic targets against this important parasite.
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Deng L, Yang W, Liu H. PredPRBA: Prediction of Protein-RNA Binding Affinity Using Gradient Boosted Regression Trees. Front Genet 2019; 10:637. [PMID: 31428122 PMCID: PMC6688581 DOI: 10.3389/fgene.2019.00637] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 06/18/2019] [Indexed: 01/24/2023] Open
Abstract
Protein-RNA interactions play essential roles in many biological aspects. Quantifying the binding affinity of protein-RNA complexes is helpful to the understanding of protein-RNA recognition mechanisms and identification of strong binding partners. Due to experimentally measured protein-RNA binding affinity data available is still limited to date, there is a pressing demand for accurate and reliable computational approaches. In this paper, we propose a computational approach, PredPRBA, which can effectively predict protein-RNA binding affinity using gradient boosted regression trees. We build a dataset of protein-RNA binding affinity that includes 103 protein-RNA complex structures manually collected from related literature. Then, we generate 37 kinds of sequence and structural features and explore the relationship between the features and protein-RNA binding affinity. We find that the binding affinity mainly depends on the structure of RNA molecules. According to the type of RNA associated with proteins composed of the protein-RNA complex, we split the 103 protein-RNA complexes into six categories. For each category, we build a gradient boosted regression tree (GBRT) model based on the generated features. We perform a comprehensive evaluation for the proposed method on the binding affinity dataset using leave-one-out cross-validation. We show that PredPRBA achieves correlations ranging from 0.723 to 0.897 among six categories, which is significantly better than other typical regression methods and the pioneer protein-RNA binding affinity predictor SPOT-Seq-RNA. In addition, a user-friendly web server has been developed to predict the binding affinity of protein-RNA complexes. The PredPRBA webserver is freely available at http://PredPRBA.denglab.org/.
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Affiliation(s)
- Lei Deng
- School of Computer Science and Engineering, Central South University, Changsha, China.,School of Software, Xinjiang University, Urumqi, China
| | - Wenyi Yang
- School of Computer Science and Engineering, Central South University, Changsha, China
| | - Hui Liu
- Lab of Information Management, Changzhou University, Changzhou, China
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Abstract
The nuclear export of ribosomal subunits (60S and 40S) depends in part on the activity of the essential auxiliary export receptors TbMtr2 and TbMex67. When these proteins are individually depleted from the medically and agriculturally significant parasite Trypanosoma brucei, distinct alterations in the processing of the rRNAs of the large subunit (60S) are observed as well as aberrations in the assembly of functional ribosomes (polysomes). We also established that TbMex67 and TbMtr2 interact directly or indirectly with the protein components of the 5S RNP, including the trypanosome-specific P34/P37. The critical role that TbMex67 and TbMtr2 play in this essential biological process together with their parasite-specific interactions may provide new therapeutic targets against this important parasite. Ribosomal maturation is a complex and highly conserved biological process involving migration of a continuously changing RNP across multiple cellular compartments. A critical point in this process is the translocation of individual ribosomal subunits (60S and 40S) from the nucleus to the cytoplasm, and a number of export factors participate in this process. In this study, we characterize the functional role of the auxiliary export receptors TbMex67 and TbMtr2 in ribosome biogenesis in the parasite Trypanosoma brucei. We demonstrate that depletion of each of these proteins dramatically impacts the steady-state levels of other proteins involved in ribosome biogenesis, including the trypanosome-specific factors P34 and P37. In addition, we observe that the loss of TbMex67 or TbMtr2 leads to aberrant ribosome formation, rRNA processing, and polysome formation. Although the TbMex67-TbMtr2 heterodimer is structurally distinct from Mex67-Mtr2 complexes previously studied, our data show that they retain a conserved function in ribosome biogenesis. IMPORTANCE The nuclear export of ribosomal subunits (60S and 40S) depends in part on the activity of the essential auxiliary export receptors TbMtr2 and TbMex67. When these proteins are individually depleted from the medically and agriculturally significant parasite Trypanosoma brucei, distinct alterations in the processing of the rRNAs of the large subunit (60S) are observed as well as aberrations in the assembly of functional ribosomes (polysomes). We also established that TbMex67 and TbMtr2 interact directly or indirectly with the protein components of the 5S RNP, including the trypanosome-specific P34/P37. The critical role that TbMex67 and TbMtr2 play in this essential biological process together with their parasite-specific interactions may provide new therapeutic targets against this important parasite.
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32
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Abstract
Gene expression is tightly regulated at the post-transcriptional level through splicing, transport, translation, and decay. RNA-binding proteins (RBPs) play key roles in post-transcriptional gene regulation, and genetic variants that alter RBP-RNA interactions can affect gene products and functions. We developed a computational method ASPRIN (Allele-Specific Protein-RNA Interaction) that uses a joint analysis of CLIP-seq (cross-linking and immunoprecipitation followed by high-throughput sequencing) and RNA-seq data to identify genetic variants that alter RBP-RNA interactions by directly observing the allelic preference of RBP from CLIP-seq experiments as compared to RNA-seq. We used ASPRIN to systematically analyze CLIP-seq and RNA-seq data for 166 RBPs in two ENCODE (Encyclopedia of DNA Elements) cell lines. ASPRIN identified genetic variants that alter RBP-RNA interactions by modifying RBP binding motifs within RNA. Moreover, through an integrative ASPRIN analysis with population-scale RNA-seq data, we showed that ASPRIN can help reveal potential causal variants that affect alternative splicing via allele-specific protein-RNA interactions.
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Affiliation(s)
- Emad Bahrami-Samani
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA; Center for Computational and Genomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Yi Xing
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA; Center for Computational and Genomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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33
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Trendel J, Schwarzl T, Horos R, Prakash A, Bateman A, Hentze MW, Krijgsveld J. The Human RNA-Binding Proteome and Its Dynamics during Translational Arrest. Cell 2019; 176:391-403.e19. [PMID: 30528433 DOI: 10.1016/j.cell.2018.11.004] [Citation(s) in RCA: 229] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 09/21/2018] [Accepted: 10/31/2018] [Indexed: 12/21/2022]
Abstract
Proteins and RNA functionally and physically intersect in multiple biological processes, however, currently no universal method is available to purify protein-RNA complexes. Here, we introduce XRNAX, a method for the generic purification of protein-crosslinked RNA, and demonstrate its versatility to study the composition and dynamics of protein-RNA interactions by various transcriptomic and proteomic approaches. We show that XRNAX captures all RNA biotypes and use this to characterize the sub-proteomes that interact with coding and non-coding RNAs (ncRNAs) and to identify hundreds of protein-RNA interfaces. Exploiting the quantitative nature of XRNAX, we observe drastic remodeling of the RNA-bound proteome during arsenite-induced stress, distinct from autophagy-related changes in the total proteome. In addition, we combine XRNAX with crosslinking immunoprecipitation sequencing (CLIP-seq) to validate the interaction of ncRNA with lamin B1 and EXOSC2. Thus, XRNAX is a resourceful approach to study structural and compositional aspects of protein-RNA interactions to address fundamental questions in RNA-biology.
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Affiliation(s)
- Jakob Trendel
- German Cancer Research Center (DKFZ), Im Neuenheimer Feld 581, Heidelberg, Germany; European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg, Germany; Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences
| | - Thomas Schwarzl
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg, Germany
| | - Rastislav Horos
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg, Germany
| | - Ananth Prakash
- European Molecular Biology Laboratory, European Bioinformatics Institute (EBI), Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Alex Bateman
- European Molecular Biology Laboratory, European Bioinformatics Institute (EBI), Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Matthias W Hentze
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg, Germany
| | - Jeroen Krijgsveld
- German Cancer Research Center (DKFZ), Im Neuenheimer Feld 581, Heidelberg, Germany; Heidelberg University, Medical Faculty, Im Neuenheimer Feld 672, Heidelberg, Germany.
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34
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Jung Y, El-Manzalawy Y, Dobbs D, Honavar VG. Partner-specific prediction of RNA-binding residues in proteins: A critical assessment. Proteins 2018; 87:198-211. [PMID: 30536635 PMCID: PMC6389706 DOI: 10.1002/prot.25639] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 10/10/2018] [Accepted: 11/29/2018] [Indexed: 01/06/2023]
Abstract
RNA-protein interactions play essential roles in regulating gene expression. While some RNA-protein interactions are "specific", that is, the RNA-binding proteins preferentially bind to particular RNA sequence or structural motifs, others are "non-RNA specific." Deciphering the protein-RNA recognition code is essential for comprehending the functional implications of these interactions and for developing new therapies for many diseases. Because of the high cost of experimental determination of protein-RNA interfaces, there is a need for computational methods to identify RNA-binding residues in proteins. While most of the existing computational methods for predicting RNA-binding residues in RNA-binding proteins are oblivious to the characteristics of the partner RNA, there is growing interest in methods for partner-specific prediction of RNA binding sites in proteins. In this work, we assess the performance of two recently published partner-specific protein-RNA interface prediction tools, PS-PRIP, and PRIdictor, along with our own new tools. Specifically, we introduce a novel metric, RNA-specificity metric (RSM), for quantifying the RNA-specificity of the RNA binding residues predicted by such tools. Our results show that the RNA-binding residues predicted by previously published methods are oblivious to the characteristics of the putative RNA binding partner. Moreover, when evaluated using partner-agnostic metrics, RNA partner-specific methods are outperformed by the state-of-the-art partner-agnostic methods. We conjecture that either (a) the protein-RNA complexes in PDB are not representative of the protein-RNA interactions in nature, or (b) the current methods for partner-specific prediction of RNA-binding residues in proteins fail to account for the differences in RNA partner-specific versus partner-agnostic protein-RNA interactions, or both.
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Affiliation(s)
- Yong Jung
- Bioinformatics and Genomics Graduate Program, Pennsylvania State University, University Park, Pennsylvania.,Artificial Intelligence Research Laboratory, Pennsylvania State University, University Park, Pennsylvania.,The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania
| | - Yasser El-Manzalawy
- Artificial Intelligence Research Laboratory, Pennsylvania State University, University Park, Pennsylvania.,Clinical and Translational Sciences Institute, Pennsylvania State University, University Park, Pennsylvania.,College of Information Sciences and Technology, Pennsylvania State University, Pennsylvania
| | - Drena Dobbs
- Bioinformatics and Computational Biology Program, Iowa State University, Ames, Iowa.,Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa
| | - Vasant G Honavar
- Bioinformatics and Genomics Graduate Program, Pennsylvania State University, University Park, Pennsylvania.,Artificial Intelligence Research Laboratory, Pennsylvania State University, University Park, Pennsylvania.,Institute for Cyberscience, Pennsylvania State University, University Park, Pennsylvania.,Clinical and Translational Sciences Institute, Pennsylvania State University, University Park, Pennsylvania.,The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania.,College of Information Sciences and Technology, Pennsylvania State University, Pennsylvania
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35
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Bandyra KJ, Wandzik JM, Luisi BF. Substrate Recognition and Autoinhibition in the Central Ribonuclease RNase E. Mol Cell 2018; 72:275-285.e4. [PMID: 30270108 DOI: 10.1016/j.molcel.2018.08.039] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/21/2018] [Accepted: 08/24/2018] [Indexed: 12/21/2022]
Abstract
The endoribonuclease RNase E is a principal factor in RNA turnover and processing that helps to exercise fine control of gene expression in bacteria. While its catalytic activity can be strongly influenced by the chemical identity of the 5′ end of RNA substrates, the enzyme can also cleave numerous substrates irrespective of the chemistry of their 5′ ends through a mechanism that has remained largely unexplained. We report structural and functional data illuminating details of both operational modes. Our crystal structure of RNase E in complex with the sRNA RprA reveals a duplex recognition site that saddles an inter-protomer surface to help present substrates for cleavage. Our data also reveal an autoinhibitory pocket that modulates the overall activity of the ribonuclease. Taking these findings together, we propose how RNase E uses versatile modes of RNA recognition to achieve optimal activity and specificity. RNase E recognizes RNA secondary structure Signature on the substrate 5′ end recognizes and activates RNase E RNase E intrinsic activity is repressed by a conserved autoinhibition motif
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36
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Chowdhury S, Zhang J, Kurgan L. In Silico Prediction and Validation of Novel RNA Binding Proteins and Residues in the Human Proteome. Proteomics 2018; 18:e1800064. [PMID: 29806170 DOI: 10.1002/pmic.201800064] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 05/05/2018] [Indexed: 12/22/2022]
Abstract
Deciphering a complete landscape of protein-RNA interactions in the human proteome remains an elusive challenge. We computationally elucidate RNA binding proteins (RBPs) using an approach that complements previous efforts. We employ two modern complementary sequence-based methods that provide accurate predictions from the structured and the intrinsically disordered sequences, even in the absence of sequence similarity to the known RBPs. We generate and analyze putative RNA binding residues on the whole proteome scale. Using a conservative setting that ensures low, 5% false positive rate, we identify 1511 putative RBPs that include 281 known RBPs and 166 RBPs that were previously predicted. We empirically demonstrate that these overlaps are statistically significant. We also validate the putative RBPs based on two major hallmarks of their RNA binding residues: high levels of evolutionary conservation and enrichment in charged amino acids. Moreover, we show that the novel RBPs are significantly under-annotated functionally which coincides with the fact that they were not yet found to interact with RNAs. We provide two examples of our novel putative RBPs for which there is recent evidence of their interactions with RNAs. The dataset of novel putative RBPs and RNA binding residues for the future hypothesis generation is provided in the Supporting Information.
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Affiliation(s)
- Shomeek Chowdhury
- Dr. Vikram Sarabhai Institute of Cell and Molecular Biology, Maharaja Sayajirao University of Baroda, Gujarat, 390005, India.,Department of Computer Science, Virginia Commonwealth University, Richmond, VA, 23284, USA
| | - Jian Zhang
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA, 23284, USA.,School of Computer and Information Technology, Xinyang Normal University, Xinyang, 464000, P. R. China
| | - Lukasz Kurgan
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA, 23284, USA
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37
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Gallagher C, Ramos A. Joining the dots - protein-RNA interactions mediating local mRNA translation in neurons. FEBS Lett 2018; 592:2932-2947. [PMID: 29856909 DOI: 10.1002/1873-3468.13121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 01/26/2023]
Abstract
Establishing and maintaining the complex network of connections required for neuronal communication requires the transport and in situ translation of large groups of mRNAs to create local proteomes. In this Review, we discuss the regulation of local mRNA translation in neurons and the RNA-binding proteins that recognise RNA zipcode elements and connect the mRNAs to the cellular transport networks, as well as regulate their translation control. However, mRNA recognition by the regulatory proteins is mediated by the combinatorial action of multiple RNA-binding domains. This increases the specificity and affinity of the interaction, while allowing the protein to recognise a diverse set of targets and mediate a range of mechanisms for translational regulation. The structural and molecular understanding of the interactions can be used together with novel microscopy and transcriptome-wide data to build a mechanistic framework for the regulation of local mRNA translation.
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Affiliation(s)
- Christopher Gallagher
- Institute of Structural and Molecular Biology, University College London, UK.,The Francis Crick Institute, London, UK
| | - Andres Ramos
- Institute of Structural and Molecular Biology, University College London, UK
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38
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Clerici M, Faini M, Aebersold R, Jinek M. Structural insights into the assembly and polyA signal recognition mechanism of the human CPSF complex. eLife 2017; 6:33111. [PMID: 29274231 PMCID: PMC5760199 DOI: 10.7554/elife.33111] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 12/21/2017] [Indexed: 12/19/2022] Open
Abstract
3' polyadenylation is a key step in eukaryotic mRNA biogenesis. In mammalian cells, this process is dependent on the recognition of the hexanucleotide AAUAAA motif in the pre-mRNA polyadenylation signal by the cleavage and polyadenylation specificity factor (CPSF) complex. A core CPSF complex comprising CPSF160, WDR33, CPSF30 and Fip1 is sufficient for AAUAAA motif recognition, yet the molecular interactions underpinning its assembly and mechanism of PAS recognition are not understood. Based on cross-linking-coupled mass spectrometry, crystal structure of the CPSF160-WDR33 subcomplex and biochemical assays, we define the molecular architecture of the core human CPSF complex, identifying specific domains involved in inter-subunit interactions. In addition to zinc finger domains in CPSF30, we identify using quantitative RNA-binding assays an N-terminal lysine/arginine-rich motif in WDR33 as a critical determinant of specific AAUAAA motif recognition. Together, these results shed light on the function of CPSF in mediating PAS-dependent RNA cleavage and polyadenylation.
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Affiliation(s)
- Marcello Clerici
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Marco Faini
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland
| | - Ruedi Aebersold
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland.,Faculty of Science, University of Zurich, Zurich, Switzerland
| | - Martin Jinek
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
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39
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Grube CD, Roy H. A continuous assay for monitoring the synthetic and proofreading activities of multiple aminoacyl-tRNA synthetases for high-throughput drug discovery. RNA Biol 2017; 15:659-666. [PMID: 29168435 PMCID: PMC6103669 DOI: 10.1080/15476286.2017.1397262] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRSs) catalyze the aminoacylation of tRNAs to produce the aminoacyl-tRNAs (aa-tRNAs) required by ribosomes for translation of the genetic message into proteins. To ensure the accuracy of tRNA aminoacylation, and consequently the fidelity of protein synthesis, some aaRSs exhibit a proofreading (editing) site, distinct from the aa-tRNA synthetic site. The aaRS editing site hydrolyzes misacylated products formed when a non-cognate amino acid is used during tRNA charging. Because aaRSs play a central role in protein biosynthesis and cellular life, these proteins represent longstanding targets for therapeutic drug development to combat infectious diseases. Most existing aaRS inhibitors target the synthetic site, and it is only recently that drugs targeting the proofreading site have been considered. In the present study, we developed a robust assay for the high-throughput screening of libraries of inhibitors targeting both the synthetic and the proofreading sites of up to four aaRSs simultaneously. Thus, this assay allows for screening of eight distinct enzyme active sites in a single experiment. aaRSs from several prominent human pathogens (i.e., Mycobacterium tuberculosis, Plasmodium falciparum, and Escherichia coli) were used for development of this assay.
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Affiliation(s)
- Christopher D Grube
- a Burnett School of Biomedical Sciences, College of Medicine , University of Central Florida , Orlando , Florida , United States of America
| | - Hervé Roy
- a Burnett School of Biomedical Sciences, College of Medicine , University of Central Florida , Orlando , Florida , United States of America
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40
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Nicastro G, Candel AM, Uhl M, Oregioni A, Hollingworth D, Backofen R, Martin SR, Ramos A. Mechanism of β-actin mRNA Recognition by ZBP1. Cell Rep 2017; 18:1187-1199. [PMID: 28147274 PMCID: PMC5300891 DOI: 10.1016/j.celrep.2016.12.091] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 11/17/2016] [Accepted: 12/28/2016] [Indexed: 01/23/2023] Open
Abstract
Zipcode binding protein 1 (ZBP1) is an oncofetal RNA-binding protein that mediates the transport and local translation of β-actin mRNA by the KH3-KH4 di-domain, which is essential for neuronal development. The high-resolution structures of KH3-KH4 with their respective target sequences show that KH4 recognizes a non-canonical GGA sequence via an enlarged and dynamic hydrophobic groove, whereas KH3 binding to a core CA sequence occurs with low specificity. A data-informed kinetic simulation of the two-step binding reaction reveals that the overall reaction is driven by the second binding event and that the moderate affinities of the individual interactions favor RNA looping. Furthermore, the concentration of ZBP1, but not of the target RNA, modulates the interaction, which explains the functional significance of enhanced ZBP1 expression during embryonic development. The dynamic groove of ZBP1’s KH4 domain allows recognition of a G-rich RNA sequence ZBP1’s KH3 and KH4 domains bind their target RNA sequences with similar affinities RNA looping drives the ZBP1-β-actin interaction The protein, rather than the RNA, concentration regulates ZBP1-β-actin mRNA binding
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Affiliation(s)
- Giuseppe Nicastro
- Macromolecular Structure Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Adela M Candel
- At the former MRC National Institute for Medical Research, Mill Hill, London
| | - Michael Uhl
- Bioinformatics Group, Department of Computer Science, University of Freiburg, 79110 Freiburg, Germany
| | - Alain Oregioni
- MRC Biomedical NMR Centre, The Francis Crick Institute, London NW1 1AT, UK
| | - David Hollingworth
- Mycobacterial Systems Biology Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Rolf Backofen
- Bioinformatics Group, Department of Computer Science, University of Freiburg, 79110 Freiburg, Germany; Centre for Biological Signaling Studies (BIOSS), University of Freiburg, 79110 Freiburg, Germany
| | - Stephen R Martin
- Structural Biology Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Andres Ramos
- Institute of Structural and Molecular Biology, University College London, London WC1E 6XA, UK; The Francis Crick Institute, London NW1 1AT, UK.
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41
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Kamina AD, Jaremko D, Christen L, Williams N. Essential Assembly Factor Rpf2 Forms Novel Interactions within the 5S RNP in Trypanosoma brucei. mSphere 2017; 2:e00394-17. [PMID: 29062898 DOI: 10.1128/mSphere.00394-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 09/29/2017] [Indexed: 01/14/2023] Open
Abstract
Ribosome biogenesis is a highly complex and conserved cellular process that is responsible for making ribosomes. During this process, there are several assembly steps that function as regulators to ensure proper ribosome formation. One of these steps is the assembly of the 5S ribonucleoprotein particle (5S RNP) in the central protuberance of the 60S ribosomal subunit. In eukaryotes, the 5S RNP is composed of 5S rRNA, ribosomal proteins L5 and L11, and assembly factors Rpf2 and Rrs1. Our laboratory previously showed that in Trypanosoma brucei, the 5S RNP is composed of 5S rRNA, L5, and trypanosome-specific RNA binding proteins P34 and P37. In this study, we characterize an additional component of the 5S RNP, the T. brucei homolog of Rpf2. This is the first study to functionally characterize interactions mediated by Rpf2 in an organism other than fungi. T. brucei Rpf2 (TbRpf2) was identified from tandem affinity purification using extracts prepared from protein A-tobacco etch virus (TEV)-protein C (PTP)-tagged L5, P34, and P37 cell lines, followed by mass spectrometry analysis. We characterized the binding interactions between TbRpf2 and the previously characterized members of the T. brucei 5S RNP. Our studies show that TbRpf2 mediates conserved binding interactions with 5S rRNA and L5 and that TbRpf2 also interacts with trypanosome-specific proteins P34 and P37. We performed RNA interference (RNAi) knockdown of TbRpf2 and showed that this protein is essential for the survival of the parasites and is critical for proper ribosome formation. These studies provide new insights into a critical checkpoint in the ribosome biogenesis pathway in T. brucei. IMPORTANCETrypanosoma brucei is the parasitic protozoan that causes African sleeping sickness. Ribosome assembly is essential for the survival of this parasite through the different host environments it encounters during its life cycle. The assembly of the 5S ribonucleoprotein particle (5S RNP) functions as one of the regulatory checkpoints during ribosome biogenesis. We have previously characterized the 5S RNP in T. brucei and showed that trypanosome-specific proteins P34 and P37 are part of this complex. In this study, we characterize for the first time the interactions of the homolog of the assembly factor Rpf2 with members of the 5S RNP in another organism besides fungi. Our studies show that Rpf2 is essential in T. brucei and that it forms unique interactions within the 5S RNP, particularly with P34 and P37. These studies have identified parasite-specific interactions that can potentially function as new therapeutic targets against sleeping sickness.
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Sánchez-Rico C, Voith von Voithenberg L, Warner L, Lamb DC, Sattler M. Effects of Fluorophore Attachment on Protein Conformation and Dynamics Studied by spFRET and NMR Spectroscopy. Chemistry 2017; 23:14267-14277. [PMID: 28799205 DOI: 10.1002/chem.201702423] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Indexed: 12/28/2022]
Abstract
Fluorescence-based techniques are widely used to study biomolecular conformations, intra- and intermolecular interactions, and conformational dynamics of macromolecules. Especially for fluorescence-based single-molecule experiments, the choice of the fluorophore and labeling position are highly important. In this work, we studied the biophysical and structural effects that are associated with the conjugation of fluorophores to cysteines in the splicing factor U2AF65 by using single pair Förster resonance energy transfer (FRET) and nuclear magnetic resonance (NMR) spectroscopy. It is shown that certain acceptor fluorophores are advantageous depending on the experiments performed. The effects of dye attachment on the protein conformation were characterized using heteronuclear NMR experiments. The presence of hydrophobic and aromatic moieties in the fluorophores can significantly affect the conformation of the conjugated protein, presumably by transient interactions with the protein surface. Guidelines are provided for carefully choosing fluorophores, considering their photophysical properties and chemical features for the design of FRET experiments, and for minimizing artifacts.
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Affiliation(s)
- Carolina Sánchez-Rico
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.,Biomolecular NMR and Center for Integrated Protein Science Munich at Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85747, Garching, Germany
| | - Lena Voith von Voithenberg
- Physical Chemistry, Department of Chemistry, Munich Center for Integrated Protein Science, Nanosystems Initiative Munich and Centre for Nanoscience, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Lisa Warner
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.,Biomolecular NMR and Center for Integrated Protein Science Munich at Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85747, Garching, Germany
| | - Don C Lamb
- Physical Chemistry, Department of Chemistry, Munich Center for Integrated Protein Science, Nanosystems Initiative Munich and Centre for Nanoscience, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.,Biomolecular NMR and Center for Integrated Protein Science Munich at Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85747, Garching, Germany
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43
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Abstract
Identification of molecular interactions is paramount to understanding how cells function. Most available technologies rely on co-purification of a protein of interest and its binding partners. Therefore, they are limited in their ability to detect low-affinity interactions and cannot be applied to proteins that localize to difficult-to-solubilize cellular compartments. In vivo proximity labeling (IPL) overcomes these obstacles by covalently tagging proteins and RNAs based on their proximity in vivo to a protein of interest. In IPL, a heterobifunctional probe comprising a photoactivatable moiety and biotin is recruited by a monomeric streptavidin tag fused to a protein of interest. Following UV irradiation, candidate interacting proteins and RNAs are covalently biotinylated with tight spatial and temporal control and subsequently recovered using biotin as an affinity handle. Here, we describe experimental protocols to discover novel protein-protein and protein-RNA interactions using IPL. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- David B Beck
- Department of Medicine, Columbia University Medical Center, New York, New York
| | - Roberto Bonasio
- Epigenetics Program, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.,Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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44
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Abstract
RNA molecules are flexible yet foldable. Proteins must cope with this structural duality when forming biologically active complexes with RNA. Recent studies of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs)-mediated RNA immunity illustrate some remarkable mechanisms with which proteins interact with RNA. Currently known structures of CRISPR-Cas6 endoribonucleases bound with RNA suggest a conserved protein recognition mechanism mediated by RNA stem-loops. However, a survey of CRISPR RNA reveals that many repeats either lack a productive stem-loop (Relaxed) or possess stable but inhibitory structures (Tight), which raises the question of how the enzyme processes structurally diverse RNA. In reviewing recent literature, we propose a bivalent trapping and an unwinding mechanism for CRISPR-Cas6 to interact with the Relaxed and the Tight repeat RNA, respectively. Both mechanisms aim to create an identical RNA conformation at the cleavage site for accurate processing.
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Affiliation(s)
- Jana Sefcikova
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA
| | - Mitchell Roth
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Ge Yu
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Hong Li
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA.,Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
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45
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Zhang Z, Lu L, Zhang Y, Hua Li C, Wang CX, Zhang XY, Tan JJ. A combinatorial scoring function for protein-RNA docking. Proteins 2017; 85:741-752. [PMID: 28120375 DOI: 10.1002/prot.25253] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 01/16/2017] [Accepted: 01/17/2017] [Indexed: 12/13/2022]
Abstract
Protein-RNA docking is still an open question. One of the main challenges is to develop an effective scoring function that can discriminate near-native structures from the incorrect ones. To solve the problem, we have constructed a knowledge-based residue-nucleotide pairwise potential with secondary structure information considered for nonribosomal protein-RNA docking. Here we developed a weighted combined scoring function RpveScore that consists of the pairwise potential and six physics-based energy terms. The weights were optimized using the multiple linear regression method by fitting the scoring function to L_rmsd for the bound docking decoys from Benchmark II. The scoring functions were tested on 35 unbound docking cases. The results show that the scoring function RpveScore including all terms performs best. Also RpveScore was compared with the statistical mechanics-based method derived potential ITScore-PR, and the united atom-based statistical potentials QUASI-RNP and DARS-RNP. The success rate of RpveScore is 71.6% for the top 1000 structures and the number of cases where a near-native structure is ranked in top 30 is 25 out of 35 cases. For 32 systems (91.4%), RpveScore can find the binding mode in top 5 that has no lower than 50% native interface residues on protein and nucleotides on RNA. Additionally, it was found that the long-range electrostatic attractive energy plays an important role in distinguishing near-native structures from the incorrect ones. This work can be helpful for the development of protein-RNA docking methods and for the understanding of protein-RNA interactions. RpveScore program is available to the public at http://life.bjut.edu.cn/kxyj/kycg/2017116/14845362285362368_1.html Proteins 2017; 85:741-752. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Zhao Zhang
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China
| | - Lin Lu
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China
| | - Yue Zhang
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China
| | - Chun Hua Li
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China
| | - Cun Xin Wang
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China
| | - Xiao Yi Zhang
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China
| | - Jian Jun Tan
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, 100124, China
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46
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Chang S, Zhang DW, Xu L, Wan H, Hou TJ, Kong R. Exploring the molecular basis of RNA recognition by the dimeric RNA-binding protein via molecular simulation methods. RNA Biol 2016; 13:1133-1143. [PMID: 27592836 DOI: 10.1080/15476286.2016.1223007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
RNA-binding protein with multiple splicing (RBPMS) is critical for axon guidance, smooth muscle plasticity, and regulation of cancer cell proliferation and migration. Recently, different states of the RNA-recognition motif (RRM) of RBPMS, one in its free form and another in complex with CAC-containing RNA, were determined by X-ray crystallography. In this article, the free RRM domain, its wild type complex and 2 mutant complex systems are studied by molecular dynamics (MD) simulations. Through comparison of free RRM domain and complex systems, it's found that the RNA binding facilitates stabilizing the RNA-binding interface of RRM domain, especially the C-terminal loop. Although both R38Q and T103A/K104A mutations reduce the binding affinity of RRM domain and RNA, the underlining mechanisms are different. Principal component analysis (PCA) and Molecular mechanics Poisson-Boltzmann surface area (MM/PBSA) methods were used to explore the dynamical and recognition mechanisms of RRM domain and RNA. R38Q mutation is positioned on the homodimerization interface and mainly induces the large fluctuations of RRM domains. This mutation does not directly act on the RNA-binding interface, but some interfacial hydrogen bonds are weakened. In contrast, T103A/K104A mutations are located on the RNA-binding interface of RRM domain. These mutations obviously break most of high occupancy hydrogen bonds in the RNA-binding interface. Meanwhile, the key interfacial residues lose their favorable energy contributions upon RNA binding. The ranking of calculated binding energies in 3 complex systems is well consistent with that of experimental binding affinities. These results will be helpful in understanding the RNA recognition mechanisms of RRM domain.
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Affiliation(s)
- Shan Chang
- a Institute of Bioinformatics and Medical Engineering, School of Electrical and Information Engineering, Jiangsu University of Technology , Changzhou , China
| | - Da-Wei Zhang
- a Institute of Bioinformatics and Medical Engineering, School of Electrical and Information Engineering, Jiangsu University of Technology , Changzhou , China
| | - Lei Xu
- a Institute of Bioinformatics and Medical Engineering, School of Electrical and Information Engineering, Jiangsu University of Technology , Changzhou , China
| | - Hua Wan
- b College of Mathematics and Informatics, South China Agricultural University , Guangzhou , China
| | - Ting-Jun Hou
- c College of Pharmaceutical Sciences, Zhejiang University , Hangzhou , China
| | - Ren Kong
- a Institute of Bioinformatics and Medical Engineering, School of Electrical and Information Engineering, Jiangsu University of Technology , Changzhou , China
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47
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Mittelberger F, Meyer C, Waetzig GH, Zacharias M, Valentini E, Svergun DI, Berg K, Lorenzen I, Grötzinger J, Rose-John S, Hahn U. RAID3--An interleukin-6 receptor-binding aptamer with post-selective modification-resistant affinity. RNA Biol 2016; 12:1043-53. [PMID: 26383776 DOI: 10.1080/15476286.2015.1079681] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Aptamers are an emerging class of highly specific targeting ligands. They can be selected in vitro for a large variety of targets, ranging from small molecules to whole cells. Most aptamers selected are nucleic acid-based, allowing chemical synthesis and easy modification. Although their properties make them interesting drug candidates for a broad spectrum of applications and an interesting alternative to antibodies or fusion proteins, they are not yet broadly used. One major drawback of aptamers is their susceptibility to abundant serum nucleases, resulting in their fast degradation in biological fluids. Using modified nucleic acids has become a common strategy to overcome these disadvantages, greatly increasing their half-life under cell culture conditions or even in vivo. Whereas pre-selective modifications of the initial library for aptamer selection are relatively easy to obtain, post-selective modifications of already selected aptamers are still generally very labor-intensive and often compromise the aptamers ability to bind its target molecule. Here we report the selection, characterization and post-selective modification of a 34 nucleotide (nt) RNA aptamer for a non-dominant, novel target site (domain 3) of the interleukin-6 receptor (IL-6R). We performed structural analyses and investigated the affinity of the aptamer to the membrane-bound and soluble forms (sIL-6R) of the IL-6R. Further, we performed structural analyses of the aptamer in solution using small-angle X-ray scattering and determined its overall shape and oligomeric state. Post-selective exchange of all pyrimidines against their 2'-fluoro analogs increased the aptamers stability significantly without compromising its affinity for the target protein. The resulting modified aptamer could be shortened to its minimal binding motif without loss of affinity.
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Affiliation(s)
- Florian Mittelberger
- a Institute for Biochemistry and Molecular Biology ; Department of Chemistry ; University of Hamburg ; Hamburg , Germany
| | - Cindy Meyer
- b Howard Hughes Medical Institute; Laboratory of RNA Molecular Biology; Rockefeller University ; New York , NY USA
| | | | - Martin Zacharias
- d Physics Department ; Technical University Munich ; Garching , Germany
| | - Erica Valentini
- a Institute for Biochemistry and Molecular Biology ; Department of Chemistry ; University of Hamburg ; Hamburg , Germany.,e European Molecular Biology Laboratory; Hamburg Unit ; Hamburg , Germany
| | - Dmitri I Svergun
- e European Molecular Biology Laboratory; Hamburg Unit ; Hamburg , Germany
| | - Katharina Berg
- a Institute for Biochemistry and Molecular Biology ; Department of Chemistry ; University of Hamburg ; Hamburg , Germany
| | - Inken Lorenzen
- f Institute of Biochemistry; University of Kiel ; Kiel , Germany
| | | | - Stefan Rose-John
- f Institute of Biochemistry; University of Kiel ; Kiel , Germany
| | - Ulrich Hahn
- a Institute for Biochemistry and Molecular Biology ; Department of Chemistry ; University of Hamburg ; Hamburg , Germany
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48
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Shao Y, Richter H, Sun S, Sharma K, Urlaub H, Randau L, Li H. A Non-Stem-Loop CRISPR RNA Is Processed by Dual Binding Cas6. Structure 2016; 24:547-554. [PMID: 26996962 PMCID: PMC4823167 DOI: 10.1016/j.str.2016.02.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 02/05/2016] [Accepted: 02/17/2016] [Indexed: 01/07/2023]
Abstract
A subclass of recently discovered CRISPR repeat RNA in bacteria contains minimally recognizable structural features that facilitate an unknown mechanism of recognition and processing by the Cas6 family of endoribonucleases. Cocrystal structures of Cas6 from Methanococcus maripaludis (MmCas6b) bound with its repeat RNA revealed a dual site binding structure and a cleavage site conformation poised for phosphodiester bond breakage. Two non-interacting MmCas6b bind to two separate AAYAA motifs within the same repeat, one distal and one adjacent to the cleavage site. This bound structure potentially competes with a stable but non-productive RNA structure. At the cleavage site, MmCas6b supplies a base pair mimic to stabilize a short 2 base pair stem immediately upstream of the scissile phosphate. Complementary biochemical analyses support the dual-AAYAA binding model and a critical role of the protein-RNA base pair mimic. Our results reveal a previously unknown method of processing non-stem-loop CRISPR RNA by Cas6.
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Affiliation(s)
- Yaming Shao
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
| | - Hagen Richter
- Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany
| | - Shengfang Sun
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA
| | - Kundan Sharma
- Bioanalytical Mass Spectrometry Group, Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Lennart Randau
- Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany,LOEWE Center for Synthetic Microbiology (Synmikro), 35043 Marburg, Germany
| | - Hong Li
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA,Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA,Correspondence should be addressed to H.L. ()
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49
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Abstract
More than one third of the cellular proteome is destined for incorporation into cell membranes or export from the cell. In all domains of life, the signal recognition particle (SRP) delivers these proteins to the membrane and protein traffic falls apart without SRP logistics. With the aid of a topogenic transport signal, SRP retrieves its cargo right at the ribosome, from where they are sorted to the translocation channel. Mammalian SRP is a ribonucleoprotein complex consisting of an SRP RNA of 300 nucleotides and 6 proteins bound to it. Assembly occurs in a hierarchical manner mainly in the nucleolus and only SRP54, which recognizes the signal sequence and regulates the targeting process, is added as the last component in the cytosol. Here we present an update on recent insights in the structure, function and dynamics of SRP RNA in SRP assembly with focus on the S domain, and present SRP as an example for the complex biogenesis of a rather small ribonucleoprotein particle.
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Affiliation(s)
- Klemens Wild
- a Heidelberg University Biochemistry Center (BZH) ; Heidelberg , Germany
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50
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Duh Y, Hsiao YY, Li CL, Huang JC, Yuan HS. Aromatic residues in RNase T stack with nucleobases to guide the sequence-specific recognition and cleavage of nucleic acids. Protein Sci 2015; 24:1934-41. [PMID: 26362012 DOI: 10.1002/pro.2800] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/02/2015] [Accepted: 09/03/2015] [Indexed: 12/30/2022]
Abstract
RNase T is a classical member of the DEDDh family of exonucleases with a unique sequence preference in that its 3'-to-5' exonuclease activity is blocked by a 3'-terminal dinucleotide CC in digesting both single-stranded RNA and DNA. Our previous crystal structure analysis of RNase T-DNA complexes show that four phenylalanine residues, F29, F77, F124, and F146, stack with the two 3'-terminal nucleobases. To elucidate if the π-π stacking interactions between aromatic residues and nucleobases play a critical role in sequence-specific protein-nucleic acid recognition, here we mutated two to four of the phenylalanine residues in RNase T to tryptophan (W mutants) and tyrosine (Y mutants). The Escherichia coli strains expressing either the W mutants or the Y mutants had slow growth phenotypes, suggesting that all of these mutants could not fully substitute the function of the wild-type RNase T in vivo. DNA digestion assays revealed W mutants shared similar sequence specificity with wild-type RNase T. However, the Y mutants exhibited altered sequence-dependent activity, digesting ssDNA with both 3'-end CC and GG sequences. Moreover, the W and Y mutants had reduced DNA-binding activity and lower thermal stability as compared to wild-type RNase T. Taken together, our results suggest that the four phenylalanine residues in RNase T not only play critical roles in sequence-specific recognition, but also in overall protein stability. Our results provide the first evidence showing that the π-π stacking interactions between nucleobases and protein aromatic residues may guide the sequence-specific activity for DNA and RNA enzymes.
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Affiliation(s)
- Yulander Duh
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, 11529, Republic of China.,Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan, 112, Republic of China
| | - Yu-Yuan Hsiao
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan, 30068, Republic of China
| | - Chia-Lung Li
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, 11529, Republic of China
| | - Jason C Huang
- Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan, 112, Republic of China
| | - Hanna S Yuan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, 11529, Republic of China.,Graduate Institute of Biochemistry and Molecular Biology, National Taiwan University, Taipei, Taiwan, 10048, Republic of China
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