1
|
Zhang Y, Zhang J, Wan H, Wu Z, Xu H, Zhang Z, Wang Y, Wang J. New Insights into the Dependence of CPEB3 Ribozyme Cleavage on Mn 2+ and Mg 2. J Phys Chem Lett 2024; 15:2708-2714. [PMID: 38427973 DOI: 10.1021/acs.jpclett.3c03221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
CPEB3 ribozyme is a self-cleaving RNA that occurs naturally in mammals and requires divalent metal ions for efficient activity. Ribozymes exhibit preferences for specific metal ions, but the exact differences in the catalytic mechanisms of various metal ions on the CPEB3 ribozyme remain unclear. Our findings reveal that Mn2+ functions as a more effective cofactor for CPEB3 ribozyme catalysis compared to Mg2+, as confirmed by its stronger binding affinity to CPEB3 by EPR. Cleavage assays of CPEB3 mutants and molecular docking analyses further showed that excessive Mn2+ ions can bind to a second binding site near the catalytic site, hindering CPEB3 catalytic efficiency and contributing to the Mn2+ bell-shaped curve. These results implicate a pivotal role for the local nucleobase-Mn2+ interactions in facilitating RNA folding and modulating the directed attack of nucleophilic reagents. Our study provides new insights and experimental evidence for exploring the divalent cation dependent cleavage mechanism of the CPEB3 ribozyme.
Collapse
Affiliation(s)
- Yaoyao Zhang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jing Zhang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hengjia Wan
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Ziwei Wu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Huangtao Xu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Zhe Zhang
- Institute for Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518055, China
| | - Yujuan Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- International Magnetobiology Frontier Research Center (iMFRC), Science Island, Hefei 230031, China
| | - Junfeng Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- University of Science and Technology of China, Hefei, Anhui 230026, China
- School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, China
- International Magnetobiology Frontier Research Center (iMFRC), Science Island, Hefei 230031, China
| |
Collapse
|
2
|
Kienbeck K, Malfertheiner L, Zelger-Paulus S, Johannsen S, von Mering C, Sigel RKO. Identification of HDV-like theta ribozymes involved in tRNA-based recoding of gut bacteriophages. Nat Commun 2024; 15:1559. [PMID: 38378708 PMCID: PMC10879173 DOI: 10.1038/s41467-024-45653-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 01/29/2024] [Indexed: 02/22/2024] Open
Abstract
Trillions of microorganisms, collectively known as the microbiome, inhabit our bodies with the gut microbiome being of particular interest in biomedical research. Bacteriophages, the dominant virome constituents, can utilize suppressor tRNAs to switch to alternative genetic codes (e.g., the UAG stop-codon is reassigned to glutamine) while infecting hosts with the standard bacterial code. However, what triggers this switch and how the bacteriophage manipulates its host is poorly understood. Here, we report the discovery of a subgroup of minimal hepatitis delta virus (HDV)-like ribozymes - theta ribozymes - potentially involved in the code switch leading to the expression of recoded lysis and structural phage genes. We demonstrate their HDV-like self-scission behavior in vitro and find them in an unreported context often located with their cleavage site adjacent to tRNAs, indicating a role in viral tRNA maturation and/or regulation. Every fifth associated tRNA is a suppressor tRNA, further strengthening our hypothesis. The vast abundance of tRNA-associated theta ribozymes - we provide 1753 unique examples - highlights the importance of small ribozymes as an alternative to large enzymes that usually process tRNA 3'-ends. Our discovery expands the short list of biological functions of small HDV-like ribozymes and introduces a previously unknown player likely involved in the code switch of certain recoded gut bacteriophages.
Collapse
Affiliation(s)
- Kasimir Kienbeck
- Department of Chemistry, University of Zurich, Zurich, CH-8057, Switzerland
| | - Lukas Malfertheiner
- Department of Molecular Life Sciences and Swiss Institute of Bioinformatics, University of Zurich, Zurich, CH-8057, Switzerland
| | | | - Silke Johannsen
- Department of Chemistry, University of Zurich, Zurich, CH-8057, Switzerland
| | - Christian von Mering
- Department of Molecular Life Sciences and Swiss Institute of Bioinformatics, University of Zurich, Zurich, CH-8057, Switzerland.
| | - Roland K O Sigel
- Department of Chemistry, University of Zurich, Zurich, CH-8057, Switzerland.
| |
Collapse
|
3
|
Schaffter SW, Wintenberg ME, Murphy TM, Strychalski EA. Design Approaches to Expand the Toolkit for Building Cotranscriptionally Encoded RNA Strand Displacement Circuits. ACS Synth Biol 2023; 12:1546-1561. [PMID: 37134273 DOI: 10.1021/acssynbio.3c00079] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Cotranscriptionally encoded RNA strand displacement (ctRSD) circuits are an emerging tool for programmable molecular computation, with potential applications spanning in vitro diagnostics to continuous computation inside living cells. In ctRSD circuits, RNA strand displacement components are continuously produced together via transcription. These RNA components can be rationally programmed through base pairing interactions to execute logic and signaling cascades. However, the small number of ctRSD components characterized to date limits circuit size and capabilities. Here, we characterize over 200 ctRSD gate sequences, exploring different input, output, and toehold sequences and changes to other design parameters, including domain lengths, ribozyme sequences, and the order in which gate strands are transcribed. This characterization provides a library of sequence domains for engineering ctRSD components, i.e., a toolkit, enabling circuits with up to 4-fold more inputs than previously possible. We also identify specific failure modes and systematically develop design approaches that reduce the likelihood of failure across different gate sequences. Lastly, we show the ctRSD gate design is robust to changes in transcriptional encoding, opening a broad design space for applications in more complex environments. Together, these results deliver an expanded toolkit and design approaches for building ctRSD circuits that will dramatically extend capabilities and potential applications.
Collapse
Affiliation(s)
- Samuel W Schaffter
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Molly E Wintenberg
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Terence M Murphy
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | | |
Collapse
|
4
|
Chen SAA, Kern AF, Ang RML, Xie Y, Fraser HB. Gene-by-environment interactions are pervasive among natural genetic variants. CELL GENOMICS 2023; 3:100273. [PMID: 37082145 PMCID: PMC10112290 DOI: 10.1016/j.xgen.2023.100273] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 10/09/2022] [Accepted: 01/31/2023] [Indexed: 04/22/2023]
Abstract
Gene-by-environment (GxE) interactions, in which a genetic variant's phenotypic effect is condition specific, are fundamental for understanding fitness landscapes and evolution but have been difficult to identify at the single-nucleotide level. Although many condition-specific quantitative trait loci (QTLs) have been mapped, these typically contain numerous inconsequential variants in linkage, precluding understanding of the causal GxE variants. Here, we introduce BARcoded Cas9 retron precise parallel editing via homology (CRISPEY-BAR), a high-throughput precision genome editing strategy, and use it to map GxE interactions of naturally occurring genetic polymorphisms impacting yeast growth. We identified hundreds of GxE variants within condition-specific QTLs, revealing unexpected genetic complexity. Moreover, we found that 93.7% of non-neutral natural variants within ergosterol biosynthesis pathway genes showed GxE interactions, including many impacting antifungal drug resistance through diverse molecular mechanisms. In sum, our results suggest an extremely complex, context-dependent fitness landscape characterized by pervasive GxE interactions while also demonstrating massively parallel genome editing as an effective means for investigating this complexity.
Collapse
Affiliation(s)
- Shi-An A. Chen
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Alexander F. Kern
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Roy Moh Lik Ang
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Yihua Xie
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Hunter B. Fraser
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Corresponding author
| |
Collapse
|
5
|
Peng H, Latifi B, Müller S, Lupták A, Chen IA. Self-cleaving ribozymes: substrate specificity and synthetic biology applications. RSC Chem Biol 2021; 2:1370-1383. [PMID: 34704043 PMCID: PMC8495972 DOI: 10.1039/d0cb00207k] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 06/14/2021] [Indexed: 12/22/2022] Open
Abstract
Various self-cleaving ribozymes appearing in nature catalyze the sequence-specific intramolecular cleavage of RNA and can be engineered to catalyze cleavage of appropriate substrates in an intermolecular fashion, thus acting as true catalysts. The mechanisms of the small, self-cleaving ribozymes have been extensively studied and reviewed previously. Self-cleaving ribozymes can possess high catalytic activity and high substrate specificity; however, substrate specificity is also engineerable within the constraints of the ribozyme structure. While these ribozymes share a common fundamental catalytic mechanism, each ribozyme family has a unique overall architecture and active site organization, indicating that several distinct structures yield this chemical activity. The multitude of catalytic structures, combined with some flexibility in substrate specificity within each family, suggests that such catalytic RNAs, taken together, could access a wide variety of substrates. Here, we give an overview of 10 classes of self-cleaving ribozymes and capture what is understood about their substrate specificity and synthetic applications. Evolution of these ribozymes in an RNA world might be characterized by the emergence of a new ribozyme family followed by rapid adaptation or diversification for specific substrates. Self-cleaving ribozymes have become important tools of synthetic biology. Here we summarize the substrate specificity and applications of the main classes of these ribozymes.![]()
Collapse
Affiliation(s)
- Huan Peng
- Department of Chemical and Biomolecular Engineering, University of California Los Angeles CA 90095 USA
| | - Brandon Latifi
- Department of Pharmaceutical Sciences, University of California Irvine CA 92697 USA
| | - Sabine Müller
- Institute for Biochemistry, University Greifswald 17487 Greifswald Germany
| | - Andrej Lupták
- Department of Pharmaceutical Sciences, University of California Irvine CA 92697 USA
| | - Irene A Chen
- Department of Chemical and Biomolecular Engineering, University of California Los Angeles CA 90095 USA
| |
Collapse
|
6
|
Montemayor EJ, Virta JM, Hayes SM, Nomura Y, Brow DA, Butcher SE. Molecular basis for the distinct cellular functions of the Lsm1-7 and Lsm2-8 complexes. RNA (NEW YORK, N.Y.) 2020; 26:1400-1413. [PMID: 32518066 PMCID: PMC7491322 DOI: 10.1261/rna.075879.120] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 06/03/2020] [Indexed: 05/04/2023]
Abstract
Eukaryotes possess eight highly conserved Lsm (like Sm) proteins that assemble into circular, heteroheptameric complexes, bind RNA, and direct a diverse range of biological processes. Among the many essential functions of Lsm proteins, the cytoplasmic Lsm1-7 complex initiates mRNA decay, while the nuclear Lsm2-8 complex acts as a chaperone for U6 spliceosomal RNA. It has been unclear how these complexes perform their distinct functions while differing by only one out of seven subunits. Here, we elucidate the molecular basis for Lsm-RNA recognition and present four high-resolution structures of Lsm complexes bound to RNAs. The structures of Lsm2-8 bound to RNA identify the unique 2',3' cyclic phosphate end of U6 as a prime determinant of specificity. In contrast, the Lsm1-7 complex strongly discriminates against cyclic phosphates and tightly binds to oligouridylate tracts with terminal purines. Lsm5 uniquely recognizes purine bases, explaining its divergent sequence relative to other Lsm subunits. Lsm1-7 loads onto RNA from the 3' end and removal of the Lsm1 carboxy-terminal region allows Lsm1-7 to scan along RNA, suggesting a gated mechanism for accessing internal binding sites. These data reveal the molecular basis for RNA binding by Lsm proteins, a fundamental step in the formation of molecular assemblies that are central to eukaryotic mRNA metabolism.
Collapse
Affiliation(s)
- Eric J Montemayor
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706, USA
| | - Johanna M Virta
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Samuel M Hayes
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Yuichiro Nomura
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - David A Brow
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706, USA
| | - Samuel E Butcher
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| |
Collapse
|
7
|
Naghdi MR, Boutet E, Mucha C, Ouellet J, Perreault J. Single Mutation in Hammerhead Ribozyme Favors Cleavage Activity with Manganese over Magnesium. Noncoding RNA 2020; 6:E14. [PMID: 32245091 PMCID: PMC7151607 DOI: 10.3390/ncrna6010014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 12/11/2022] Open
Abstract
Hammerhead ribozymes are one of the most studied classes of ribozymes so far, from both the structural and biochemical point of views. The activity of most hammerhead ribozymes is cation-dependent. Mg2+ is one of the most abundant divalent cations in the cell and therefore plays a major role in cleavage activity for most hammerhead ribozymes. Besides Mg2+, cleavage can also occur in the presence of other cations such as Mn2+. The catalytic core of hammerhead ribozymes is highly conserved, which could contribute to a preference of hammerhead ribozymes toward certain cations. Here, we show a naturally occurring variation in the catalytic core of hammerhead ribozymes, A6C, that can favor one metallic ion, Mn2+, over several other cations.
Collapse
Affiliation(s)
- Mohammad Reza Naghdi
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, 531 boul. des Prairies, Laval, QB H7V 1B7, Canada; (M.R.N.); (E.B.); (C.M.)
| | - Emilie Boutet
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, 531 boul. des Prairies, Laval, QB H7V 1B7, Canada; (M.R.N.); (E.B.); (C.M.)
| | - Clarisse Mucha
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, 531 boul. des Prairies, Laval, QB H7V 1B7, Canada; (M.R.N.); (E.B.); (C.M.)
| | - Jonathan Ouellet
- Department of Chemistry and Physics, Monmouth University, 400 Cedar Avenue, West Long Branch, NJ 07764, USA;
| | - Jonathan Perreault
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, 531 boul. des Prairies, Laval, QB H7V 1B7, Canada; (M.R.N.); (E.B.); (C.M.)
| |
Collapse
|
8
|
Yamagami R, Kayedkhordeh M, Mathews DH, Bevilacqua PC. Design of highly active double-pseudoknotted ribozymes: a combined computational and experimental study. Nucleic Acids Res 2019; 47:29-42. [PMID: 30462314 PMCID: PMC6326823 DOI: 10.1093/nar/gky1118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 10/24/2018] [Indexed: 01/02/2023] Open
Abstract
Design of RNA sequences that adopt functional folds establishes principles of RNA folding and applications in biotechnology. Inverse folding for RNAs, which allows computational design of sequences that adopt specific structures, can be utilized for unveiling RNA functions and developing genetic tools in synthetic biology. Although many algorithms for inverse RNA folding have been developed, the pseudoknot, which plays a key role in folding of ribozymes and riboswitches, is not addressed in most algorithms. For the few algorithms that attempt to predict pseudoknot-containing ribozymes, self-cleavage activity has not been tested. Herein, we design double-pseudoknot HDV ribozymes using an inverse RNA folding algorithm and test their kinetic mechanisms experimentally. More than 90% of the positively designed ribozymes possess self-cleaving activity, whereas more than 70% of negative control ribozymes, which are predicted to fold to the necessary structure but with low fidelity, do not possess it. Kinetic and mutation analyses reveal that these RNAs cleave site-specifically and with the same mechanism as the WT ribozyme. Most ribozymes react just 50- to 80-fold slower than the WT ribozyme, and this rate can be improved to near WT by modification of a junction. Thus, fast-cleaving functional ribozymes with multiple pseudoknots can be designed computationally.
Collapse
Affiliation(s)
- Ryota Yamagami
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA.,Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Mohammad Kayedkhordeh
- Department of Biochemistry & Biophysics and Center for RNA Biology, University of Rochester Medical Center, Rochester, New York, NY 14642, USA
| | - David H Mathews
- Department of Biochemistry & Biophysics and Center for RNA Biology, University of Rochester Medical Center, Rochester, New York, NY 14642, USA.,Department of Biostatistics & Computational Biology, University of Rochester Medical Center, Rochester, New York, NY 14642, USA
| | - Philip C Bevilacqua
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA.,Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA.,Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
| |
Collapse
|
9
|
Cotranscriptional 3'-End Processing of T7 RNA Polymerase Transcripts by a Smaller HDV Ribozyme. J Mol Evol 2018; 86:425-430. [PMID: 30099590 DOI: 10.1007/s00239-018-9861-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 07/28/2018] [Indexed: 10/28/2022]
Abstract
In vitro run-off transcription by T7 RNA polymerase generates heterogeneous 3'-ends because the enzyme tends to add untemplated adenylates. To generate homogeneous 3'-termini, HDV ribozymes have been used widely. Their sequences are added to the 3'-terminus such that co-transcriptional self-cleavage generates homogeneous 3'-ends. A shorter HDV sequence that cleaves itself efficiently would be advantageous. Here we show that a recently discovered, small HDV ribozyme is a good alternative to the previously used HDV ribozyme. The new HDV ribozyme is more efficient in some sequence contexts, and less efficient in other sequence contexts than the previously used HDV ribozyme. The smaller size makes the new HDV ribozyme a good alternative for transcript 3'-end processing.
Collapse
|
10
|
Architecture of the U6 snRNP reveals specific recognition of 3'-end processed U6 snRNA. Nat Commun 2018; 9:1749. [PMID: 29717126 PMCID: PMC5931518 DOI: 10.1038/s41467-018-04145-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 04/06/2018] [Indexed: 01/09/2023] Open
Abstract
The spliceosome removes introns from precursor messenger RNA (pre-mRNA) to produce mature mRNA. Prior to catalysis, spliceosomes are assembled de novo onto pre-mRNA substrates. During this assembly process, U6 small nuclear RNA (snRNA) undergoes extensive structural remodeling. The early stages of this remodeling process are chaperoned by U6 snRNP proteins Prp24 and the Lsm2-8 heteroheptameric ring. We now report a structure of the U6 snRNP from Saccharomyces cerevisiae. The structure reveals protein-protein contacts that position Lsm2-8 in close proximity to the chaperone "active site" of Prp24. The structure also shows how the Lsm2-8 ring specifically recognizes U6 snRNA that has been post-transcriptionally modified at its 3' end, thereby elucidating the mechanism by which U6 snRNPs selectively recruit 3' end-processed U6 snRNA into spliceosomes. Additionally, the structure reveals unanticipated homology between the C-terminal regions of Lsm8 and the cytoplasmic Lsm1 protein involved in mRNA decay.
Collapse
|
11
|
Webb CHT, Lupták A. Kinetic Parameters of trans Scission by Extended HDV-like Ribozymes and the Prospect for the Discovery of Genomic trans-Cleaving RNAs. Biochemistry 2018; 57:1440-1450. [PMID: 29388767 DOI: 10.1021/acs.biochem.7b00789] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Hepatitis delta virus (HDV)-like ribozymes are self-cleaving catalytic RNAs with a widespread distribution in nature and biological roles ranging from self-scission during rolling-circle replication in viroids to co-transcriptional processing of eukaryotic retrotransposons, among others. The ribozymes fold into a double pseudoknot with a common catalytic core motif and highly variable peripheral domains. Like other self-cleaving ribozymes, HDV-like ribozymes can be converted into trans-acting catalytic RNAs by bisecting the self-cleaving variants at non-essential loops. Here we explore the trans-cleaving activity of ribozymes derived from the largest examples of the ribozymes (drz-Agam-2 family), which contain an extended domain between the substrate strand and the rest of the RNA. When this peripheral domain is bisected at its distal end, the substrate strand is recognized through two helices, rather than just one 7 bp helix common among the HDV ribozymes, resulting in stronger binding and increased sequence specificity. Kinetic characterization of the extended trans-cleaving ribozyme revealed an efficient trans-cleaving system with a surprisingly high KM', supporting a model that includes a recently proposed activation barrier related to the assembly of the catalytically competent ribozyme. The ribozymes also exhibit a very long koff for the products (∼2 weeks), resulting in a trade-off between sequence specificity and turnover. Finally, structure-based searches for the catalytic cores of these ribozymes in the genome of the mosquito Anopheles gambiae, combined with sequence searches for their putative substrates, revealed two potential ribozyme-substrate pairs that may represent examples of natural trans-cleaving ribozymes.
Collapse
Affiliation(s)
- Chiu-Ho T Webb
- Department of Molecular Biology and Biochemistry , University of California-Irvine , Irvine , California 92697 , United States
| | - Andrej Lupták
- Department of Molecular Biology and Biochemistry , University of California-Irvine , Irvine , California 92697 , United States.,Department of Pharmaceutical Sciences , University of California-Irvine , Irvine , California 92697 , United States.,Department of Chemistry , University of California-Irvine , Irvine , California 92697 , United States
| |
Collapse
|
12
|
Passalacqua LFM, Jimenez RM, Fong JY, Lupták A. Allosteric Modulation of the Faecalibacterium prausnitzii Hepatitis Delta Virus-like Ribozyme by Glucosamine 6-Phosphate: The Substrate of the Adjacent Gene Product. Biochemistry 2017; 56:6006-6014. [PMID: 29045794 DOI: 10.1021/acs.biochem.7b00879] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Self-cleaving ribozymes were discovered 30 years ago and have been found throughout nature, from bacteria to animals, but little is known about their biological functions and regulation, particularly how cofactors and metabolites alter their activity. A hepatitis delta virus-like self-cleaving ribozyme maps upstream of a phosphoglucosamine mutase (glmM) open reading frame in the genome of the human gut bacterium Faecalibacterium prausnitzii. The presence of a ribozyme in the untranslated region of glmM suggests a regulation mechanism of gene expression. In the bacterial hexosamine biosynthesis pathway, the enzyme glmM catalyzes the isomerization of glucosamine 6-phosphate into glucosamine 1-phosphate. In this study, we investigated the effect of these metabolites on the co-transcriptional self-cleavage rate of the ribozyme. Our results suggest that glucosamine 6-phosphate, but not glucosamine 1-phosphate, is an allosteric ligand that increases the self-cleavage rate of drz-Fpra-1, providing the first known example of allosteric modulation of a self-cleaving ribozyme by the substrate of the adjacent gene product. Given that the ribozyme is activated by the glmM substrate, but not the product, this allosteric modulation may represent a potential feed-forward mechanism of gene expression regulation in bacteria.
Collapse
Affiliation(s)
- Luiz F M Passalacqua
- Department of Pharmaceutical Sciences, University of California , Irvine, California 92697, United States
| | - Randi M Jimenez
- Department of Molecular Biology and Biochemistry, University of California , Irvine, California 92697, United States
| | - Jennifer Y Fong
- Department of Pharmaceutical Sciences, University of California , Irvine, California 92697, United States
| | - Andrej Lupták
- Department of Pharmaceutical Sciences, University of California , Irvine, California 92697, United States.,Department of Molecular Biology and Biochemistry, University of California , Irvine, California 92697, United States.,Department of Chemistry, University of California , Irvine, California 92697, United States
| |
Collapse
|
13
|
Bingaman JL, Messina KJ, Bevilacqua PC. Probing fast ribozyme reactions under biological conditions with rapid quench-flow kinetics. Methods 2017; 120:125-134. [PMID: 28315484 DOI: 10.1016/j.ymeth.2017.03.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/28/2017] [Accepted: 03/10/2017] [Indexed: 11/24/2022] Open
Abstract
Reaction kinetics on the millisecond timescale pervade the protein and RNA fields. To study such reactions, investigators often perturb the system with abiological solution conditions or substrates in order to slow the rate to timescales accessible by hand mixing; however, such perturbations can change the rate-limiting step and obscure key folding and chemical steps that are found under biological conditions. Mechanical methods for collecting data on the millisecond timescale, which allow these perturbations to be avoided, have been developed over the last few decades. These methods are relatively simple and can be conducted on affordable and commercially available instruments. Here, we focus on using the rapid quench-flow technique to study the fast reaction kinetics of RNA enzymes, or ribozymes, which often react on the millisecond timescale under biological conditions. Rapid quench of ribozymes is completely parallel to the familiar hand-mixing approach, including the use of radiolabeled RNAs and fractionation of reactions on polyacrylamide gels. We provide tips on addressing and preventing common problems that can arise with the rapid-quench technique. Guidance is also offered on ensuring the ribozyme is properly folded and fast-reacting. We hope that this article will facilitate the broader use of rapid-quench instrumentation to study fast-reacting ribozymes under biological reaction conditions.
Collapse
Affiliation(s)
- Jamie L Bingaman
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA 16802, United States.
| | - Kyle J Messina
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA 16802, United States
| | - Philip C Bevilacqua
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA 16802, United States; Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, United States.
| |
Collapse
|
14
|
Topological constraints of structural elements in regulation of catalytic activity in HDV-like self-cleaving ribozymes. Sci Rep 2016; 6:28179. [PMID: 27302490 PMCID: PMC4908430 DOI: 10.1038/srep28179] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 05/31/2016] [Indexed: 11/09/2022] Open
Abstract
Self-cleaving ribozymes fold into intricate structures, which orient active site groups into catalytically competent conformations. Most ribozyme families have distinct catalytic cores stabilized by tertiary interactions between domains peripheral to those cores. We show that large hepatitis delta virus (HDV)-like ribozymes are activated by peripheral domains that bring two helical segments, P1 and P2, into proximity – a “pinch” that results in rate acceleration by almost three orders of magnitude. Kinetic analysis of ribozymes with systematically altered length and stability of the peripheral domain revealed that about one third of its free energy of formation is used to lower an activation energy barrier, likely related to a rate-limiting conformational change leading to the pre-catalytic state. These findings provide a quantitative view of enzyme regulation by peripheral domains and may shed light on the energetics of allosteric regulation.
Collapse
|
15
|
Rampášek L, Jimenez RM, Lupták A, Vinař T, Brejová B. RNA motif search with data-driven element ordering. BMC Bioinformatics 2016; 17:216. [PMID: 27188396 PMCID: PMC4870747 DOI: 10.1186/s12859-016-1074-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 05/07/2016] [Indexed: 01/30/2023] Open
Abstract
Background In this paper, we study the problem of RNA motif search in long genomic sequences. This approach uses a combination of sequence and structure constraints to uncover new distant homologs of known functional RNAs. The problem is NP-hard and is traditionally solved by backtracking algorithms. Results We have designed a new algorithm for RNA motif search and implemented a new motif search tool RNArobo. The tool enhances the RNAbob descriptor language, allowing insertions in helices, which enables better characterization of ribozymes and aptamers. A typical RNA motif consists of multiple elements and the running time of the algorithm is highly dependent on their ordering. By approaching the element ordering problem in a principled way, we demonstrate more than 100-fold speedup of the search for complex motifs compared to previously published tools. Conclusions We have developed a new method for RNA motif search that allows for a significant speedup of the search of complex motifs that include pseudoknots. Such speed improvements are crucial at a time when the rate of DNA sequencing outpaces growth in computing. RNArobo is available at http://compbio.fmph.uniba.sk/rnarobo. Electronic supplementary material The online version of this article (doi:10.1186/s12859-016-1074-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Ladislav Rampášek
- Department of Computer Science, University of Toronto, Toronto, M5R 3G4, ON, Canada.,Department of Pharmaceutical Sciences, Chemistry, and Molecular Biology and Biochemistry, University of California, Irvine, 2141 Natural Sciences 2, Irvine, 92697, CA, USA.,Faculty of Mathematics, Physics, and Informatics, Comenius University, Mlynská dolina, Bratislava, 842 48, Slovakia
| | - Randi M Jimenez
- Department of Pharmaceutical Sciences, Chemistry, and Molecular Biology and Biochemistry, University of California, Irvine, 2141 Natural Sciences 2, Irvine, 92697, CA, USA
| | - Andrej Lupták
- Department of Pharmaceutical Sciences, Chemistry, and Molecular Biology and Biochemistry, University of California, Irvine, 2141 Natural Sciences 2, Irvine, 92697, CA, USA.
| | - Tomáš Vinař
- Faculty of Mathematics, Physics, and Informatics, Comenius University, Mlynská dolina, Bratislava, 842 48, Slovakia
| | - Broňa Brejová
- Faculty of Mathematics, Physics, and Informatics, Comenius University, Mlynská dolina, Bratislava, 842 48, Slovakia.
| |
Collapse
|
16
|
Skilandat M, Rowinska-Zyrek M, Sigel RKO. Secondary structure confirmation and localization of Mg2+ ions in the mammalian CPEB3 ribozyme. RNA (NEW YORK, N.Y.) 2016; 22:750-763. [PMID: 26966151 PMCID: PMC4836649 DOI: 10.1261/rna.053843.115] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 01/04/2016] [Indexed: 06/05/2023]
Abstract
Most of today's knowledge of the CPEB3 ribozyme, one of the few small self-cleaving ribozymes known to occur in humans, is based on comparative studies with the hepatitis delta virus (HDV) ribozyme, which is highly similar in cleavage mechanism and probably also in structure. Here we present detailed NMR studies of the CPEB3 ribozyme in order to verify the formation of the predicted nested double pseudoknot in solution. In particular, the influence of Mg(2+), the ribozyme's crucial cofactor, on the CPEB3 structure is investigated. NMR titrations, Tb(3+)-induced cleavage, as well as stoichiometry determination by hydroxyquinoline sulfonic acid fluorescence and equilibrium dialysis, are used to evaluate the number, location, and binding mode of Mg(2+)ions. Up to eight Mg(2+)ions interact site-specifically with the ribozyme, four of which are bound with high affinity. The global fold of the CPEB3 ribozyme, encompassing 80%-90% of the predicted base pairs, is formed in the presence of monovalent ions alone. Low millimolar concentrations of Mg(2+)promote a more compact fold and lead to the formation of additional structures in the core of the ribozyme, which contains the inner small pseudoknot and the active site. Several Mg(2+)binding sites, which are important for the functional fold, appear to be located in corresponding locations in the HDV and CPEB3 ribozyme, demonstrating the particular relevance of Mg(2+)for the nested double pseudoknot structure.
Collapse
Affiliation(s)
- Miriam Skilandat
- Department of Chemistry, University of Zurich, CH-8057 Zurich, Switzerland
| | | | - Roland K O Sigel
- Department of Chemistry, University of Zurich, CH-8057 Zurich, Switzerland
| |
Collapse
|
17
|
Kozlyuk N, Sengupta S, Lupták A, Martin RW. In situ NMR measurement of macromolecule-bound metal ion concentrations. JOURNAL OF BIOMOLECULAR NMR 2016; 64:269-273. [PMID: 27108020 DOI: 10.1007/s10858-016-0031-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 04/15/2016] [Indexed: 06/05/2023]
Abstract
Many nucleic acids and proteins require divalent metal ions such as Mg(2+) and Ca(2+) for folding and function. The lipophilic alignment media frequently used as membrane mimetics also bind these divalent metals. Here we demonstrate the use of (31)P NMR spectrum of a metal ion chelator (deoxycytidine diphosphate) to measure the bound [Mg(2+)] and [Ca(2+)] in situ for several biological model systems at relatively high divalent ion concentrations (1-10 mM). This method represents a general approach to measuring divalent metal ion binding in NMR samples where the amount and type of metal ion added to the system is known.
Collapse
Affiliation(s)
- Natalia Kozlyuk
- Department of Chemistry, University of California, Irvine, CA, 92697, USA
| | - Suvrajit Sengupta
- Department of Chemistry, University of California, Irvine, CA, 92697, USA
| | - Andrej Lupták
- Department of Chemistry, University of California, Irvine, CA, 92697, USA.
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697, USA.
- Department of Pharmaceutical Sciences, University of California, Irvine, CA, 92697, USA.
| | - Rachel W Martin
- Department of Chemistry, University of California, Irvine, CA, 92697, USA.
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697, USA.
| |
Collapse
|
18
|
Lee TS, Radak BK, Harris ME, York DM. A Two-Metal-Ion-Mediated Conformational Switching Pathway for HDV Ribozyme Activation. ACS Catal 2016; 6:1853-1869. [PMID: 27774349 DOI: 10.1021/acscatal.5b02158] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
RNA enzymes serve as a potentially powerful platform from which to design catalysts and engineer new biotechnology. A fundamental understanding of these systems provides insight to guide design. The hepatitis delta virus ribozyme (HDVr) is a small, self-cleaving RNA motif widely distributed in nature, that has served as a paradigm for understanding basic principles of RNA catalysis. Nevertheless, questions remain regarding the precise roles of divalent metal ions and key nucleotides in catalysis. In an effort to establish a reaction mechanism model consistent with available experimental data, we utilize molecular dynamics simulations to explore different conformations and metal ion binding modes along the HDVr reaction path. Building upon recent crystallographic data, our results provide a dynamic model of the HDVr reaction mechanism involving a conformational switch between multiple non-canonical G25:U20 base pair conformations in the active site. These local nucleobase dynamics play an important role in catalysis by modulating the metal binding environments of two Mg2+ ions that support catalysis at different steps of the reaction pathway. The first ion plays a structural role by inducing a base pair flip necessary to obtain the catalytic fold in which C75 moves towards to the scissile phosphate in the active site. Ejection of this ion then permits a second ion to bind elsewhere in the active site and facilitate nucleophile activation. The simulations collectively describe a mechanistic scenario that is consistent with currently available experimental data from crystallography, phosphorothioate substitutions, and chemical probing studies. Avenues for further experimental verification are suggested.
Collapse
Affiliation(s)
- Tai-Sung Lee
- Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Brian K. Radak
- Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
- Argonne National Laboratory, Argonne, Illinois 60439, United State
| | - Michael E. Harris
- Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
| | - Darrin M. York
- Center for Integrative Proteomics Research and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| |
Collapse
|