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Chamberlain AR, Huynh L, Huang W, Taylor DJ, Harris ME. The specificity landscape of bacterial ribonuclease P. J Biol Chem 2024; 300:105498. [PMID: 38013087 PMCID: PMC10731613 DOI: 10.1016/j.jbc.2023.105498] [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: 07/24/2023] [Revised: 11/14/2023] [Accepted: 11/17/2023] [Indexed: 11/29/2023] Open
Abstract
Developing quantitative models of substrate specificity for RNA processing enzymes is a key step toward understanding their biology and guiding applications in biotechnology and biomedicine. Optimally, models to predict relative rate constants for alternative substrates should integrate an understanding of structures of the enzyme bound to "fast" and "slow" substrates, large datasets of rate constants for alternative substrates, and transcriptomic data identifying in vivo processing sites. Such data are either available or emerging for bacterial ribonucleoprotein RNase P a widespread and essential tRNA 5' processing endonuclease, thus making it a valuable model system for investigating principles of biological specificity. Indeed, the well-established structure and kinetics of bacterial RNase P enabled the development of high throughput measurements of rate constants for tRNA variants and provided the necessary framework for quantitative specificity modeling. Several studies document the importance of conformational changes in the precursor tRNA substrate as well as the RNA and protein subunits of bacterial RNase P during binding, although the functional roles and dynamics are still being resolved. Recently, results from cryo-EM studies of E. coli RNase P with alternative precursor tRNAs are revealing prospective mechanistic relationships between conformational changes and substrate specificity. Yet, extensive uncharted territory remains, including leveraging these advances for drug discovery, achieving a complete accounting of RNase P substrates, and understanding how the cellular context contributes to RNA processing specificity in vivo.
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Affiliation(s)
| | - Loc Huynh
- Department of Chemistry, University of Florida, Gainesville, Florida, USA
| | - Wei Huang
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | - Derek J Taylor
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | - Michael E Harris
- Department of Chemistry, University of Florida, Gainesville, Florida, USA.
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Singh A, Batra JK. Insight into the functional role of unique determinants in RNA component of RNase P of Mycobacterium tuberculosis. Int J Biol Macromol 2018; 119:937-944. [PMID: 30086331 DOI: 10.1016/j.ijbiomac.2018.08.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/03/2018] [Accepted: 08/04/2018] [Indexed: 10/28/2022]
Abstract
RNase P, an essential ribonucleoprotein enzyme is involved in processing 5' end of pre-tRNA molecules. All bacterial RNase P holoenzymes, including that of Mycobacterim tuberculosis, an important human pathogen contain a catalytically active RNA subunit and a protein subunit. However, the mycobacterial RNA is larger than typical bacterial RNase P RNAs. It contains the essential core structure and many unique features in the peripheral elements. In the current study, an extensive mutational analysis was performed to analyze the function of the unique features in P12, P15.A, P18 and P19 helices in the mycobacterial RNase P RNA. The study demonstrates that P12 interacts with monovalent and divalent ions and is important for the function of mycobacterial holoenzyme. The helices, P15.A and P18 appear to interact with ammonium and magnesium ions, respectively. P19 is involved in the thermostability of the RNA component as well as interaction with ammonium ions. A homology model of M. tuberculosis RNase P RNA indicates many new inter- and intra-helical interactions. The significance of the unique interactions paves way towards understanding the differential functioning of M. tuberculosis RNase P RNA, for exploring specific inhibition of the same in the pathogen to contain infection.
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Affiliation(s)
- Alla Singh
- Immunochemistry Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Janendra K Batra
- Immunochemistry Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India; Department of Biochemistry, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India.
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Saito Y, Takeda J, Adachi K, Nobe Y, Kobayashi J, Hirota K, Oliveira DV, Taoka M, Isobe T. RNase MRP cleaves pre-tRNASer-Met in the tRNA maturation pathway. PLoS One 2014; 9:e112488. [PMID: 25401760 PMCID: PMC4234475 DOI: 10.1371/journal.pone.0112488] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 10/17/2014] [Indexed: 01/07/2023] Open
Abstract
Ribonuclease mitochondrial RNA processing (RNase MRP) is a multifunctional ribonucleoprotein (RNP) complex that is involved in the maturation of various types of RNA including ribosomal RNA. RNase MRP consists of a potential catalytic RNA and several protein components, all of which are required for cell viability. We show here that the temperature-sensitive mutant of rmp1, the gene for a unique protein component of RNase MRP, accumulates the dimeric tRNA precursor, pre-tRNASer-Met. To examine whether RNase MRP mediates tRNA maturation, we purified the RNase MRP holoenzyme from the fission yeast Schizosaccharomyces pombe and found that the enzyme directly and selectively cleaves pre-tRNASer-Met, suggesting that RNase MRP participates in the maturation of specific tRNA in vivo. In addition, mass spectrometry–based ribonucleoproteomic analysis demonstrated that this RNase MRP consists of one RNA molecule and 11 protein components, including a previously unknown component Rpl701. Notably, limited nucleolysis of RNase MRP generated an active catalytic core consisting of partial mrp1 RNA fragments, which constitute “Domain 1” in the secondary structure of RNase MRP, and 8 proteins. Thus, the present study provides new insight into the structure and function of RNase MRP.
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Affiliation(s)
- Yuichiro Saito
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Tokyo, Japan
| | - Jun Takeda
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
| | - Kousuke Adachi
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Tokyo, Japan
| | - Yuko Nobe
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
| | - Junya Kobayashi
- Division of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Kouji Hirota
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Tokyo, Japan
| | - Douglas V. Oliveira
- Division of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto, Japan
| | - Masato Taoka
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Tokyo, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
| | - Toshiaki Isobe
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Tokyo, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
- * E-mail:
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Garcia-Martin JA, Clote P, Dotu I. RNAiFOLD: a constraint programming algorithm for RNA inverse folding and molecular design. J Bioinform Comput Biol 2013; 11:1350001. [PMID: 23600819 DOI: 10.1142/s0219720013500017] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Synthetic biology is a rapidly emerging discipline with long-term ramifications that range from single-molecule detection within cells to the creation of synthetic genomes and novel life forms. Truly phenomenal results have been obtained by pioneering groups--for instance, the combinatorial synthesis of genetic networks, genome synthesis using BioBricks, and hybridization chain reaction (HCR), in which stable DNA monomers assemble only upon exposure to a target DNA fragment, biomolecular self-assembly pathways, etc. Such work strongly suggests that nanotechnology and synthetic biology together seem poised to constitute the most transformative development of the 21st century. In this paper, we present a Constraint Programming (CP) approach to solve the RNA inverse folding problem. Given a target RNA secondary structure, we determine an RNA sequence which folds into the target structure; i.e. whose minimum free energy structure is the target structure. Our approach represents a step forward in RNA design--we produce the first complete RNA inverse folding approach which allows for the specification of a wide range of design constraints. We also introduce a Large Neighborhood Search approach which allows us to tackle larger instances at the cost of losing completeness, while retaining the advantages of meeting design constraints (motif, GC-content, etc.). Results demonstrate that our software, RNAiFold, performs as well or better than all state-of-the-art approaches; nevertheless, our approach is unique in terms of completeness, flexibility, and the support of various design constraints. The algorithms presented in this paper are publicly available via the interactive webserver http://bioinformatics.bc.edu/clotelab/RNAiFold; additionally, the source code can be downloaded from that site.
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Abstract
Nuclear ribonuclease (RNase) P is a ubiquitous essential ribonucleoprotein complex, one of only two known RNA-based enzymes found in all three domains of life. The RNA component is the catalytic moiety of RNases P across all phylogenetic domains; it contains a well-conserved core, whereas peripheral structural elements are diverse. RNA components of eukaryotic RNases P tend to be less complex than their bacterial counterparts, a simplification that is accompanied by a dramatic reduction of their catalytic ability in the absence of protein. The size and complexity of the protein moieties increase dramatically from bacterial to archaeal to eukaryotic enzymes, apparently reflecting the delegation of some structural functions from RNA to proteins and, perhaps, in response to the increased complexity of the cellular environment in the more evolutionarily advanced organisms; the reasons for the increased dependence on proteins are not clear. We review current information on RNase P and the closely related universal eukaryotic enzyme RNase MRP, focusing on their functions and structural organization.
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Affiliation(s)
- Olga Esakova
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Sun FJ, Caetano-Anollés G. The ancient history of the structure of ribonuclease P and the early origins of Archaea. BMC Bioinformatics 2010; 11:153. [PMID: 20334683 PMCID: PMC2858038 DOI: 10.1186/1471-2105-11-153] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Accepted: 03/24/2010] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Ribonuclease P is an ancient endonuclease that cleaves precursor tRNA and generally consists of a catalytic RNA subunit (RPR) and one or more proteins (RPPs). It represents an important macromolecular complex and model system that is universally distributed in life. Its putative origins have inspired fundamental hypotheses, including the proposal of an ancient RNA world. RESULTS To study the evolution of this complex, we constructed rooted phylogenetic trees of RPR molecules and substructures and estimated RPP age using a cladistic method that embeds structure directly into phylogenetic analysis. The general approach was used previously to study the evolution of tRNA, SINE RNA and 5S rRNA, the origins of metabolism, and the evolution and complexity of the protein world, and revealed here remarkable evolutionary patterns. Trees of molecules uncovered the tripartite nature of life and the early origin of archaeal RPRs. Trees of substructures showed molecules originated in stem P12 and were accessorized with a catalytic P1-P4 core structure before the first substructure was lost in Archaea. This core currently interacts with RPPs and ancient segments of the tRNA molecule. Finally, a census of protein domain structure in hundreds of genomes established RPPs appeared after the rise of metabolic enzymes at the onset of the protein world. CONCLUSIONS The study provides a detailed account of the history and early diversification of a fundamental ribonucleoprotein and offers further evidence in support of the existence of a tripartite organismal world that originated by the segregation of archaeal lineages from an ancient community of primordial organisms.
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Affiliation(s)
- Feng-Jie Sun
- Evolutionary Bioinformatics Laboratory, Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Laboratory of Molecular Epigenetics of the Ministry of Education, School of Life Sciences, Northeast Normal University, Changchun 130024, Jilin Province, PR China
- W.M. Keck Center for Comparative and Functional Genomics, Roy J. Carver Biotechnology Center, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Gustavo Caetano-Anollés
- Evolutionary Bioinformatics Laboratory, Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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Abstract
MOTIVATION The structure of RNA molecules is often crucial for their function. Therefore, secondary structure prediction has gained much interest. Here, we consider the inverse RNA folding problem, which means designing RNA sequences that fold into a given structure. RESULTS We introduce a new algorithm for the inverse folding problem (INFO-RNA) that consists of two parts; a dynamic programming method for good initial sequences and a following improved stochastic local search that uses an effective neighbor selection method. During the initialization, we design a sequence that among all sequences adopts the given structure with the lowest possible energy. For the selection of neighbors during the search, we use a kind of look-ahead of one selection step applying an additional energy-based criterion. Afterwards, the pre-ordered neighbors are tested using the actual optimization criterion of minimizing the structure distance between the target structure and the mfe structure of the considered neighbor. We compared our algorithm to RNAinverse and RNA-SSD for artificial and biological test sets. Using INFO-RNA, we performed better than RNAinverse and in most cases, we gained better results than RNA-SSD, the probably best inverse RNA folding tool on the market. AVAILABILITY www.bioinf.uni-freiburg.de?Subpages/software.html.
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Affiliation(s)
- Anke Busch
- Albert-Ludwigs-University Freiburg, Institute of Computer Science, Chair of Bioinformatics Georges-Koehler-Allee 106, 79110 Freiburg, Germany
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Piccinelli P, Rosenblad MA, Samuelsson T. Identification and analysis of ribonuclease P and MRP RNA in a broad range of eukaryotes. Nucleic Acids Res 2005; 33:4485-95. [PMID: 16087735 PMCID: PMC1183490 DOI: 10.1093/nar/gki756] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
RNases P and MRP are ribonucleoprotein complexes involved in tRNA and rRNA processing, respectively. The RNA subunits of these two enzymes are structurally related to each other and play an essential role in the enzymatic reaction. Both of the RNAs have a highly conserved helical region, P4, which is important in the catalytic reaction. We have used a bioinformatics approach based on conserved elements to computationally analyze available genomic sequences of eukaryotic organisms and have identified a large number of novel nuclear RNase P and MRP RNA genes. For MRP RNA for instance, this investigation increases the number of known sequences by a factor of three. We present secondary structure models of many of the predicted RNAs. Although all sequences are able to fold into the consensus secondary structure of P and MRP RNAs, a striking variation in size is observed, ranging from a Nosema locustae MRP RNA of 160 nt to much larger RNAs, e.g. a Plasmodium knowlesi P RNA of 696 nt. The P and MRP RNA genes appear in tandem in some protists, further emphasizing the close evolutionary relationship of these RNAs.
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Affiliation(s)
- Paul Piccinelli
- Department of Medical Biochemistry, Goteborg UniversityBox 440, SE-405 30 Göteborg, Sweden
| | - Magnus Alm Rosenblad
- Department of Medical Biochemistry, Goteborg UniversityBox 440, SE-405 30 Göteborg, Sweden
- SWEGENE Bioinformatics, Goteborg UniversityBox 413, SE-405 30 Goteborg, Sweden
| | - Tore Samuelsson
- Department of Medical Biochemistry, Goteborg UniversityBox 440, SE-405 30 Göteborg, Sweden
- To whom correspondence should be addressed. Tel: +46 31 773 34 68; Fax +46 31 41 61 08;
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Andronescu M, Fejes AP, Hutter F, Hoos HH, Condon A. A new algorithm for RNA secondary structure design. J Mol Biol 2004; 336:607-24. [PMID: 15095976 DOI: 10.1016/j.jmb.2003.12.041] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2003] [Revised: 12/12/2003] [Accepted: 12/12/2003] [Indexed: 11/27/2022]
Abstract
The function of many RNAs depends crucially on their structure. Therefore, the design of RNA molecules with specific structural properties has many potential applications, e.g. in the context of investigating the function of biological RNAs, of creating new ribozymes, or of designing artificial RNA nanostructures. Here, we present a new algorithm for solving the following RNA secondary structure design problem: given a secondary structure, find an RNA sequence (if any) that is predicted to fold to that structure. Unlike the (pseudoknot-free) secondary structure prediction problem, this problem appears to be hard computationally. Our new algorithm, "RNA Secondary Structure Designer (RNA-SSD)", is based on stochastic local search, a prominent general approach for solving hard combinatorial problems. A thorough empirical evaluation on computationally predicted structures of biological sequences and artificially generated RNA structures as well as on empirically modelled structures from the biological literature shows that RNA-SSD substantially out-performs the best known algorithm for this problem, RNAinverse from the Vienna RNA Package. In particular, the new algorithm is able to solve structures, consistently, for which RNAinverse is unable to find solutions. The RNA-SSD software is publically available under the name of RNA Designer at the RNASoft website (www.rnasoft.ca).
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Affiliation(s)
- Mirela Andronescu
- Department of Computer Science, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
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Harris ME, Christian EL. Recent insights into the structure and function of the ribonucleoprotein enzyme ribonuclease P. Curr Opin Struct Biol 2003; 13:325-33. [PMID: 12831883 DOI: 10.1016/s0959-440x(03)00069-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In bacteria, the tRNA-processing endonuclease ribonuclease P is composed of a large ( approximately 400 nucleotide) catalytic RNA and a smaller ( approximately 100 amino acid) protein subunit that is essential for substrate recognition. Current biochemical and biophysical investigations are providing fresh insights into the modular architecture of the ribozyme, the mechanisms of substrate specificity and the role of essential metal ions in catalysis. Together with recent high-resolution structures of portions of the ribozyme, these findings are beginning to reveal how the functions of RNA and protein are coordinated in this ribonucleoprotein enzyme.
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Affiliation(s)
- Michael E Harris
- Center for RNA Molecular Biology, Case Western Reserve University, School of Medicine, 44106, Cleveland, OH 44106, USA.
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Ohuchi SJ, Ikawa Y, Shiraishi H, Inoue T. Modular engineering of a Group I intron ribozyme. Nucleic Acids Res 2002; 30:3473-80. [PMID: 12140333 PMCID: PMC137077 DOI: 10.1093/nar/gkf453] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
All Group I intron ribozymes contain a conserved core region consisting of two helical domains, P4-P6 and P3-P7. Recent studies have demonstrated that the elements required for catalysis are concentrated in the P3-P7 domain. We carried out in vitro selection experiments by using three newly constructed libraries on a variant of the T4 td Group I ribozyme containing only a P3-P7 domain in its core. Selected variants with new peripheral elements at L7.1, L8 or L9 after nine cycles efficiently catalyzed the reversal reaction of the first step of self-splicing. The variants from this selection contained a short sequence complementary to the substrate RNA without exception. The most active variant, which was 3-fold more active than the parental wild-type ribozyme, was developed from the second selection by employing a clone from the first selection. The results show that the P3-P7 domain can stand as an independent catalytic module to which a variety of new domains for enhancing the activity of the ribozyme can be added.
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Affiliation(s)
- Shoji J Ohuchi
- Graduate School of Science and. Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
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Affiliation(s)
- T A Hall
- Department of Microbiology, North Carolina State University, Raleigh, North Carolina 27695, USA
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Abstract
Ribonuclease P (RNase P) is an essential endonuclease that acts early in the tRNA biogenesis pathway. This enzyme catalyzes cleavage of the leader sequence of precursor tRNAs (pre-tRNAs), generating the mature 5' end of tRNAs. RNase P activities have been identified in Bacteria, Archaea, and Eucarya, as well as organelles. Most forms of RNase P are ribonucleoproteins, i.e., they consist of an essential RNA subunit and protein subunits, although the composition of the enzyme in mitochondria and chloroplasts is still under debate. The recent purification of the eukaryotic nuclear RNase P has demonstrated a significantly larger protein content compared to the bacterial enzyme. Moreover, emerging evidence suggests that the eukaryotic RNase P has evolved into at least two related nuclear enzymes with distinct functions, RNase P and RNase MRP. Here we review current information on RNase P, with emphasis on the composition, structure, and functions of the eukaryotic nuclear holoenzyme, and its relationship with RNase MRP.
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Affiliation(s)
- Shaohua Xiao
- Department of Biological Chemistry, 3200 MSRB III, 1150 W. Medical Center Drive, University of Michigan, Ann Arbor, Michigan 48109-0606
| | - Felicia Scott
- Department of Biological Chemistry, 3200 MSRB III, 1150 W. Medical Center Drive, University of Michigan, Ann Arbor, Michigan 48109-0606
| | - Carol A. Fierke
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606
| | - David R. Engelke
- Department of Biological Chemistry, 3200 MSRB III, 1150 W. Medical Center Drive, University of Michigan, Ann Arbor, Michigan 48109-0606
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Loria A, Pan T. Modular construction for function of a ribonucleoprotein enzyme: the catalytic domain of Bacillus subtilis RNase P complexed with B. subtilis RNase P protein. Nucleic Acids Res 2001; 29:1892-7. [PMID: 11328872 PMCID: PMC37254 DOI: 10.1093/nar/29.9.1892] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The bacterial RNase P holoenzyme catalyzes the formation of the mature 5'-end of tRNAs and is composed of an RNA and a protein subunit. Among the two folding domains of the RNase P RNA, the catalytic domain (C-domain) contains the active site of this ribozyme. We investigated specific binding of the Bacillus subtilis C-domain with the B.subtilis RNase P protein and examined the catalytic activity of this C-domain-P protein complex. The C-domain forms a specific complex with the P protein with a binding constant of approximately 0.1 microM. The C-domain-P protein complex and the holoenzyme are equally efficient in cleaving single-stranded RNA (approximately 0.9 min(-1) at pH 7.8) and substrates with a hairpin-loop 3' to the cleavage site (approximately 40 min(-1)). The holoenzyme reaction is much more efficient with a pre-tRNA substrate, binding at least 100-fold better and cleaving 10-500 times more efficiently. These results demonstrate that the RNase P holoenzyme is functionally constructed in three parts. The catalytic domain alone contains the active site, but has little specificity and affinity for most substrates. The specificity and affinity for the substrate is generated by either the specificity domain of RNase P RNA binding to a T stem-loop-like hairpin or RNase P protein binding to a single-stranded RNA. This modular construction may be exploited to obtain RNase P-based ribonucleoprotein complexes with altered substrate specificity.
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Affiliation(s)
- A Loria
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
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