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Sharts DM, Almanza MT, Banks AV, Castellanos AM, O Hernandez CG, Lopez ML, Rodriguez D, Tong AY, Segeberg MR, M Passalacqua LF, Abdelsayed MM. Robo-Therm, a pipeline to RNA Thermometer discovery and validation. RNA 2024:rna.079980.124. [PMID: 38565243 DOI: 10.1261/rna.079980.124] [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] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 03/20/2024] [Indexed: 04/04/2024]
Abstract
RNA thermometers are highly structured noncoding RNAs located in the 5' untranslated regions (UTR) of genes that regulate expression by undergoing conformational changes in response to temperature. The discovery of RNA thermometers through bioinformatics is difficult because there is little sequence conservation among their structural elements. Thus, the abundance of these thermo-sensitive regulatory structures remains unclear. Herein, to advance the discovery and validation of RNA thermometers, we developed Robo-Therm, a pipeline that combines an adaptive and user-friendly in silico motif search with a well-established reporter system. Through our application of Robo-Therm, we discovered two novel RNA thermometers in bacterial and bacteriophage genomes found in the human gut. One of these thermometers is present in 5'-UTR of a gene that codes for σ70 RNA polymerase subunit in the bacteria Mediterraneibacter gnavus and Bacteroides pectinophilus, and in the bacteriophage Caudoviricetes, which infects Bacteroides pectinophilus. The other thermometer is in the 5'-UTR of a tetracycline resistance gene (tetR) in the intestinal bacteria Escherichia coli and Shigella flexneri. Our Robo-Therm pipeline can be applied to discover multiple RNA thermometers across various genomes.
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2
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Tong A, Caudill EE, Jones AR, F. M. Passalacqua L, Abdelsayed MM. Characterization of a FourU RNA Thermometer in the 5' Untranslated Region of Autolysin Gene blyA in the Bacillus subtilis 168 Prophage SPβ. Biochemistry 2023; 62:2902-2907. [PMID: 37699513 PMCID: PMC10586365 DOI: 10.1021/acs.biochem.3c00368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/28/2023] [Indexed: 09/14/2023]
Abstract
RNA thermometers are noncoding RNA structures located in the 5' untranslated regions (UTRs) of genes that regulate gene expression through temperature-dependent conformational changes. The fourU class of RNA thermometers contains a specific motif in which four consecutive uracil nucleotides are predicted to base pair with the Shine-Dalgarno (SD) sequence in a stem. We employed a bioinformatic search to discover a fourU RNA thermometer in the 5'-UTR of the blyA gene of the Bacillus subtilis phage SPβc2, a bacteriophage that infects B. subtilis 168. blyA encodes an autolysin enzyme, N-acetylmuramoyl-l-alanine amidase, which is involved in the lytic life cycle of the SPβ prophage. We have biochemically validated the predicted RNA thermometer in the 5'-UTR of the blyA gene. Our study suggests that RNA thermometers may play an underappreciated yet critical role in the lytic life cycle of bacteriophages.
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Affiliation(s)
- Alina
Y. Tong
- Department
of Biology, California Lutheran University, Thousand Oaks, California 91360, United States
| | - Emma E. Caudill
- Department
of Biology, California Lutheran University, Thousand Oaks, California 91360, United States
| | - Alexis R. Jones
- Department
of Biology, California Lutheran University, Thousand Oaks, California 91360, United States
| | - Luiz F. M. Passalacqua
- Laboratory
of Nucleic Acids, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Michael M. Abdelsayed
- Department
of Biology, California Lutheran University, Thousand Oaks, California 91360, United States
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3
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Chen CC, Han J, Chinn CA, Rounds JS, Li X, Nikan M, Myszka M, Tong L, Passalacqua LFM, Bredy TW, Wood MA, Lupták A. Inhibition of CPEB3 ribozyme elevates CPEB3 protein expression and polyadenylation of its target mRNAs, and enhances object location memory. bioRxiv 2023:2023.06.07.543953. [PMID: 37333407 PMCID: PMC10274809 DOI: 10.1101/2023.06.07.543953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
A self-cleaving ribozyme that maps to an intron of the cytoplasmic polyadenylation element binding protein 3 (CPEB3) gene is thought to play a role in human episodic memory, but the underlying mechanisms mediating this effect are not known. We tested the activity of the murine sequence and found that the ribozyme's self-scission half-life matches the time it takes an RNA polymerase to reach the immediate downstream exon, suggesting that the ribozyme-dependent intron cleavage is tuned to co-transcriptional splicing of the CPEB3 mRNA. Our studies also reveal that the murine ribozyme modulates maturation of its harboring mRNA in both cultured cortical neurons and the hippocampus: inhibition of the ribozyme using an antisense oligonucleotide leads to increased CPEB3 protein expression, which enhances polyadenylation and translation of localized plasticity-related target mRNAs, and subsequently strengthens hippocampal-dependent long-term memory. These findings reveal a previously unknown role for self-cleaving ribozyme activity in regulating experience-induced co-transcriptional and local translational processes required for learning and memory.
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Affiliation(s)
- Claire C. Chen
- Department of Pharmaceutical Sciences, University of California–Irvine, Irvine, California 92697, United States
| | - Joseph Han
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Carlene A. Chinn
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Jacob S. Rounds
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Xiang Li
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Mehran Nikan
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Marie Myszka
- Department of Chemistry, University of California–Irvine, Irvine, California 92697, United States
| | - Liqi Tong
- Institute for Memory Impairments and Neurological Disorders, University of California–Irvine, Irvine, California 92697, United States
| | - Luiz F. M. Passalacqua
- Department of Pharmaceutical Sciences, University of California–Irvine, Irvine, California 92697, United States
| | - Timothy W. Bredy
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Marcelo A. Wood
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Andrej Lupták
- 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
- Department of Molecular Biology and Biochemistry, University of California–Irvine, Irvine, California 92697, United States
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4
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Passalacqua LFM, Banco MT, Moon JD, Li X, Jaffrey SR, Ferré-D'Amaré AR. Intricate 3D architecture of a DNA mimic of GFP. Nature 2023; 618:1078-1084. [PMID: 37344591 PMCID: PMC10754392 DOI: 10.1038/s41586-023-06229-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 05/16/2023] [Indexed: 06/23/2023]
Abstract
Numerous studies have shown how RNA molecules can adopt elaborate three-dimensional (3D) architectures1-3. By contrast, whether DNA can self-assemble into complex 3D folds capable of sophisticated biochemistry, independent of protein or RNA partners, has remained mysterious. Lettuce is an in vitro-evolved DNA molecule that binds and activates4 conditional fluorophores derived from GFP. To extend previous structural studies5,6 of fluorogenic RNAs, GFP and other fluorescent proteins7 to DNA, we characterize Lettuce-fluorophore complexes by X-ray crystallography and cryogenic electron microscopy. The results reveal that the 53-nucleotide DNA adopts a four-way junction (4WJ) fold. Instead of the canonical L-shaped or H-shaped structures commonly seen8 in 4WJ RNAs, the four stems of Lettuce form two coaxial stacks that pack co-linearly to form a central G-quadruplex in which the fluorophore binds. This fold is stabilized by stacking, extensive nucleobase hydrogen bonding-including through unusual diagonally stacked bases that bridge successive tiers of the main coaxial stacks of the DNA-and coordination of monovalent and divalent cations. Overall, the structure is more compact than many RNAs of comparable size. Lettuce demonstrates how DNA can form elaborate 3D structures without using RNA-like tertiary interactions and suggests that new principles of nucleic acid organization will be forthcoming from the analysis of complex DNAs.
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Affiliation(s)
- Luiz F M Passalacqua
- Laboratory of Nucleic Acids, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Michael T Banco
- Laboratory of Nucleic Acids, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jared D Moon
- Department of Pharmacology, Weill-Cornell Medical College, Cornell University, New York, NY, USA
| | - Xing Li
- Department of Pharmacology, Weill-Cornell Medical College, Cornell University, New York, NY, USA
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Samie R Jaffrey
- Department of Pharmacology, Weill-Cornell Medical College, Cornell University, New York, NY, USA
| | - Adrian R Ferré-D'Amaré
- Laboratory of Nucleic Acids, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
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5
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Passalacqua LFM, Starich MR, Link KA, Wu J, Knutson JR, Tjandra N, Jaffrey SR, Ferré-D'Amaré AR. Co-crystal structures of the fluorogenic aptamer Beetroot show that close homology may not predict similar RNA architecture. Nat Commun 2023; 14:2969. [PMID: 37221204 PMCID: PMC10205801 DOI: 10.1038/s41467-023-38683-3] [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: 12/12/2022] [Accepted: 05/11/2023] [Indexed: 05/25/2023] Open
Abstract
Beetroot is a homodimeric in vitro selected RNA that binds and activates DFAME, a conditional fluorophore derived from GFP. It is 70% sequence-identical to the previously characterized homodimeric aptamer Corn, which binds one molecule of its cognate fluorophore DFHO at its interprotomer interface. We have now determined the Beetroot-DFAME co-crystal structure at 1.95 Å resolution, discovering that this RNA homodimer binds two molecules of the fluorophore, at sites separated by ~30 Å. In addition to this overall architectural difference, the local structures of the non-canonical, complex quadruplex cores of Beetroot and Corn are distinctly different, underscoring how subtle RNA sequence differences can give rise to unexpected structural divergence. Through structure-guided engineering, we generated a variant that has a 12-fold fluorescence activation selectivity switch toward DFHO. Beetroot and this variant form heterodimers and constitute the starting point for engineered tags whose through-space inter-fluorophore interaction could be used to monitor RNA dimerization.
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Affiliation(s)
- Luiz F M Passalacqua
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Mary R Starich
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Katie A Link
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jiahui Wu
- Department of Pharmacology, Weill-Cornell Medical College, Cornell University, New York, NY, USA
- Department of Chemistry, Binghamton University, Binghamton, NY, 13902, USA
| | - Jay R Knutson
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Nico Tjandra
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Samie R Jaffrey
- Department of Pharmacology, Weill-Cornell Medical College, Cornell University, New York, NY, USA
| | - Adrian R Ferré-D'Amaré
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
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6
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Trachman RJ, Passalacqua LFM, Ferré-D'Amaré AR. The bacterial yjdF riboswitch regulates translation through its tRNA-like fold. J Biol Chem 2022; 298:101934. [PMID: 35427649 PMCID: PMC9142559 DOI: 10.1016/j.jbc.2022.101934] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/08/2022] [Accepted: 04/09/2022] [Indexed: 10/27/2022] Open
Abstract
Unlike most riboswitches, which have one cognate effector, the bacterial yjdF riboswitch binds to diverse azaaromatic compounds, only a subset of which cause it to activate translation. We examined the yjdF aptamer domain by small-angle X-ray scattering, and found that in the presence of activating ligands, the RNA adopts an overall shape similar to that of tRNA. Sequence analyses suggested that the yjdF aptamer is a homolog of tRNALys, and that two of the conserved loops of the riboswitch are equivalent to the D- and T-loops of tRNA, associating to form an elbow-like tertiary interaction. Chemical probing indicated that this association is promoted by activating ligands such as chelerythrine and harmine. In its native mRNA context, activator ligands stabilize the tRNA-like fold of the yjdF aptamer, outcompeting the attenuated state in which its T-loop base-pairs to the Shine-Dalgarno element of the mRNA. Moreover, we demonstrate that the liganded aptamer itself activates translation, as authentic tRNAs, when grafted into mRNA, can potently activate translation. Taken together, our data demonstrate the ability of tRNA to function as a small-molecule responsive cis regulatory element.
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Affiliation(s)
- Robert J Trachman
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, 50 South Drive MSC 8012, Bethesda, MD 20892-8012, USA.
| | - Luiz F M Passalacqua
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, 50 South Drive MSC 8012, Bethesda, MD 20892-8012, USA
| | - Adrian R Ferré-D'Amaré
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, 50 South Drive MSC 8012, Bethesda, MD 20892-8012, USA
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7
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Chizzolini F, Kent AD, Passalacqua LFM, Lupták A. Enzymatic RNA Production from NTPs Synthesized from Nucleosides and Trimetaphosphate*. Chembiochem 2021; 22:2098-2101. [PMID: 33798271 DOI: 10.1002/cbic.202100085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/29/2021] [Indexed: 01/22/2023]
Abstract
A mechanism of nucleoside triphosphorylation would have been critical in an evolving "RNA world" to provide high-energy substrates for reactions such as RNA polymerization. However, synthetic approaches to produce ribonucleoside triphosphates (rNTPs) have suffered from conditions such as high temperatures or high pH that lead to increased RNA degradation, as well as substrate production that cannot sustain replication. Previous reports have demonstrated that cyclic trimetaphosphate (cTmp) can react with nucleosides to form rNTPs under prebiotically-relevant conditions, but their reaction rates were unknown and the influence of reaction conditions not well-characterized. Here we established a sensitive assay that allowed for the determination of second-order rate constants for all four rNTPs, ranging from 1.7×10-6 to 6.5×10-6 M-1 s-1 . The ATP reaction shows a linear dependence on pH and Mg2+ , and an enthalpy of activation of 88±4 kJ/mol. At millimolar nucleoside and cTmp concentrations, the rNTP production rate is sufficient to facilitate RNA synthesis by both T7 RNA polymerase and a polymerase ribozyme. We suggest that the optimized reaction of cTmp with nucleosides may provide a viable connection between prebiotic nucleotide synthesis and RNA replication.
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Affiliation(s)
- Fabio Chizzolini
- Department of Pharmaceutical Sciences, University of California at Irvine, Irvine, CA, 92617, USA
| | - Alexandra D Kent
- Department of Chemistry, University of California at Irvine, Irvine, CA, 92617, USA
| | - Luiz F M Passalacqua
- Department of Pharmaceutical Sciences, University of California at Irvine, Irvine, CA, 92617, USA
| | - Andrej Lupták
- Department of Pharmaceutical Sciences, University of California at Irvine, Irvine, CA, 92617, USA.,Department of Chemistry, University of California at Irvine, Irvine, CA, 92617, USA.,Department of Molecular Biology and Biochemistry, University of California at Irvine, Irvine, CA, 92617, USA
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8
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Abstract
RNA molecules can be conveniently synthesized in vitro by the T7 RNA polymerase (T7 RNAP). In some experiments, such as cotranscriptional biochemical analyses, continuous synthesis of RNA is not desired. Here, we propose a method for a single-pass transcription that yields a single transcript per template DNA molecule using the T7 RNAP system. We hypothesized that stalling the polymerase downstream from the promoter region and subsequent cleavage of the promoter by a restriction enzyme (to prevent promoter binding by another polymerase) would allow synchronized production of a single transcript per template. The single-pass transcription was verified in two different scenarios: a short self-cleaving ribozyme and a long mRNA. The results show that a controlled single-pass transcription using T7 RNAP allows precise measurement of cotranscriptional ribozyme activity, and this approach will facilitate the study of other kinetic events.
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Affiliation(s)
- Luiz F M Passalacqua
- Department of Pharmaceutical Sciences, University of California, Irvine, California 92697, USA
| | - Armine I Dingilian
- Department of Pharmaceutical Sciences, University of California, Irvine, California 92697, USA
| | - Andrej Lupták
- Department of Pharmaceutical Sciences, University of California, Irvine, California 92697, USA
- Department of Chemistry, University of California, Irvine, California 92697, USA
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697, USA
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9
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Chizzolini F, Passalacqua LFM, Oumais M, Dingilian AI, Szostak JW, Lupták A. Large Phenotypic Enhancement of Structured Random RNA Pools. J Am Chem Soc 2020; 142:1941-1951. [PMID: 31887027 DOI: 10.1021/jacs.9b11396] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Laboratory evolution of functional RNAs has applications in many areas of chemical and synthetic biology. In vitro selections critically depend on the presence of functional molecules, such as aptamers and ribozymes, in the starting sequence pools. For selection of novel functions the pools are typically transcribed from random-sequence DNA templates, yielding a highly diverse set of RNAs that contain a multitude of folds and biochemical activities. The phenotypic potential, the frequency of functional RNAs, is very low, requiring large complexity of starting pools, surpassing 1015 different sequences, to identify highly active isolates. Furthermore, the majority of random sequences is not structured and has a high propensity for aggregation; the in vitro selection process thus involves not just enrichment of functional RNAs, but also their purification from aggregation-prone "free-riders". We reasoned that purification of the nonaggregating, monomeric subpopulation of a random-sequence RNA pool will yield pools of folded, functional RNAs. We performed six rounds of selection for monomeric sequences and show that the enriched population is compactly folded. In vitro selections originating from various mixtures of the compact pool and a fully random pool showed that sequences from the compact pool always dominate the population once a biochemical activity is detectable. A head-to-head competition of the two pools starting from a low (5 × 1012) sequence diversity revealed that the phenotypic potential of the compact pool is about 1000-times higher than the fully random pool. A selection for folded and monomeric RNA pools thus greatly increases the frequency of functional RNAs from that seen in random-sequence pools, providing a facile experimental approach to isolation of highly active functional RNAs from low-diversity populations.
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Affiliation(s)
- Fabio Chizzolini
- Department of Pharmaceutical Sciences , University of California at Irvine , Irvine , California 92697 , United States
| | - Luiz F M Passalacqua
- Department of Pharmaceutical Sciences , University of California at Irvine , Irvine , California 92697 , United States
| | - Mona Oumais
- Department of Chemistry , University of California at Irvine , Irvine , California 92697 , United States
| | - Armine I Dingilian
- Department of Pharmaceutical Sciences , University of California at Irvine , Irvine , California 92697 , United States
| | - Jack W Szostak
- Howard Hughes Medical Institute, Department of Molecular Biology, and Center for Computational and Integrative Biology , Massachusetts General Hospital , Boston , Massachusetts 02114 , United States.,Department of Chemistry and Chemical Biology , Harvard University , 12 Oxford Street , Cambridge , Massachusetts 02138 , United States
| | - Andrej Lupták
- Department of Pharmaceutical Sciences , University of California at Irvine , Irvine , California 92697 , United States.,Department of Chemistry , University of California at Irvine , Irvine , California 92697 , United States.,Department of Molecular Biology and Biochemistry , University of California at Irvine , Irvine , California 92697 , United States
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10
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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] [What about the content of this article? (0)] [Affiliation(s)] [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.
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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
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