1
|
Jaiswal LK, Singh RK, Nayak T, Kakkar A, Kandwal G, Singh VS, Gupta A. A comparative analysis of mycobacterial ribonucleases: Towards a therapeutic novel drug target. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2024; 123:105645. [PMID: 39067582 DOI: 10.1016/j.meegid.2024.105645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 06/18/2024] [Accepted: 07/21/2024] [Indexed: 07/30/2024]
Abstract
Bacterial responses to continuously changing environments are addressed through modulation of gene expression at the level of transcription initiation, RNA processing and/or decay. Ribonucleases (RNases) are hydrolytic or phosphorolytic enzymes involved in a majority of RNA metabolism reactions. RNases play a crucial role in RNA degradation, either independently or in collaboration with various trans-acting regulatory factors. The genus Mycobacterium consists of five subgenera: Mycobacteroides, Mycolicibacterium, Mycobacterium, Mycolicibacter and Mycolicibacillus, which include 63 fully sequenced species (pathogenic/non-pathogenic) to date. These include 13 different RNases, among which 5 are exonucleases (RNase PH, PNPase, RNase D, nano-RNases and RNase AS) and 8 are endonucleases (RNase J, RNase H, RNase P, RNase III, RNase BN, RNase Z, RNase G and RNase E), although RNase J and RNase BN were later identified to have exoribonuclease functions also. Here, we provide a detailed comparative insight into the Escherichia coli and mycobacterial RNases with respect to their types, phylogeny, structure, function, regulation and mechanism of action, with the main emphasis on RNase E. Among these 13 different mycobacterial RNases, 10 are essential for cell survival and have diverse structures hence, they are promising drug targets. RNase E is also an essential endonuclease that is abundant in many bacteria, forms an RNA degradosome complex that controls central RNA processing/degradation and has a conserved 5' sensor domain/DNase-I like region in its RNase domain. The essential mycobacterial RNases especially RNase E provide a potential repertoire of drug targets that can be exploited for inhibitor/modulator screening against many deadly mycobacterial diseases.
Collapse
Affiliation(s)
- Lav Kumar Jaiswal
- Molecular Microbiology Laboratory, Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi U.P.-221005, India
| | - Rakesh Kumar Singh
- Molecular Microbiology Laboratory, Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi U.P.-221005, India
| | - Tanmayee Nayak
- Molecular Microbiology Laboratory, Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi U.P.-221005, India
| | - Anuja Kakkar
- Molecular Microbiology Laboratory, Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi U.P.-221005, India
| | - Garima Kandwal
- Molecular Microbiology Laboratory, Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi U.P.-221005, India
| | - Vijay Shankar Singh
- Department of Microbiology, School of life Sciences, Sikkim University, Gangtok 737102, Sikkim, India
| | - Ankush Gupta
- Molecular Microbiology Laboratory, Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi U.P.-221005, India.
| |
Collapse
|
2
|
Laalami S, Cavaiuolo M, Oberto J, Putzer H. Membrane Localization of RNase Y Is Important for Global Gene Expression in Bacillus subtilis. Int J Mol Sci 2024; 25:8537. [PMID: 39126106 PMCID: PMC11313650 DOI: 10.3390/ijms25158537] [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: 07/08/2024] [Revised: 07/27/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024] Open
Abstract
RNase Y is a key endoribonuclease that regulates global mRNA turnover and processing in Bacillus subtilis and likely many other bacteria. This enzyme is anchored to the cell membrane, creating a pseudo-compartmentalization that aligns with its role in initiating the decay of mRNAs primarily translated at the cell periphery. However, the reasons behind and the consequences of RNase Y's membrane attachment remain largely unknown. In our study, we examined a strain expressing wild-type levels of a cytoplasmic form of RNase Y from its chromosomal locus. This strain exhibits a slow-growth phenotype, similar to that of an RNase Y null mutant. Genome-wide data reveal a significant impact on the expression of hundreds of genes. While certain RNA substrates clearly depend on RNase Y's membrane attachment, others do not. We observed no correlation between mRNA stabilization in the mutant strains and the cellular location or function of the encoded proteins. Interestingly, the Y-complex, a specificity factor for RNase Y, also appears also recognize the cytoplasmic form of the enzyme, restoring wild-type levels of the corresponding transcripts. We propose that membrane attachment of RNase Y is crucial for its functional interaction with many coding and non-coding RNAs, limiting the cleavage of specific substrates, and potentially avoiding unfavorable competition with other ribonucleases like RNase J, which shares a similar evolutionarily conserved cleavage specificity.
Collapse
Affiliation(s)
- Soumaya Laalami
- Expression Génétique Microbienne, CNRS, Institut de Biologie Physico-Chimique, Université Paris Cité, 75005 Paris, France; (S.L.)
| | - Marina Cavaiuolo
- Expression Génétique Microbienne, CNRS, Institut de Biologie Physico-Chimique, Université Paris Cité, 75005 Paris, France; (S.L.)
- Laboratory for Food Safety, SBCL Unit, University Paris Est, ANSES, 94701 Maisons-Alfort, France
| | - Jacques Oberto
- Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France;
| | - Harald Putzer
- Expression Génétique Microbienne, CNRS, Institut de Biologie Physico-Chimique, Université Paris Cité, 75005 Paris, France; (S.L.)
| |
Collapse
|
3
|
Garg R, Manhas I, Chaturvedi D. Unveiling the orchestration: mycobacterial small RNAs as key mediators in host-pathogen interactions. Front Microbiol 2024; 15:1399280. [PMID: 38903780 PMCID: PMC11188477 DOI: 10.3389/fmicb.2024.1399280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 05/21/2024] [Indexed: 06/22/2024] Open
Abstract
Small RNA (sRNA) molecules, a class of non-coding RNAs, have emerged as pivotal players in the regulation of gene expression and cellular processes. Mycobacterium tuberculosis and other pathogenic mycobacteria produce diverse small RNA species that modulate bacterial physiology and pathogenesis. Recent advances in RNA sequencing have enabled identification of novel small RNAs and characterization of their regulatory functions. This review discusses the multifaceted roles of bacterial small RNAs, covering their biogenesis, classification, and functional diversity. Small RNAs (sRNAs) play pivotal roles in orchestrating diverse cellular processes, ranging from gene silencing to epigenetic modifications, across a broad spectrum of organisms. While traditionally associated with eukaryotic systems, recent research has unveiled their presence and significance within bacterial domains as well. Unlike their eukaryotic counterparts, which primarily function within the context of RNA interference (RNAi) pathways, bacterial sRNAs predominantly act through base-pairing interactions with target mRNAs, leading to post-transcriptional regulation. This fundamental distinction underscores the necessity of elucidating the unique roles and regulatory mechanisms of bacterial sRNAs in bacterial adaptation and survival. By doing these myriad functions, they regulate bacterial growth, metabolism, virulence, and drug resistance. In Mycobacterium tuberculosis, apart from having various roles in the bacillus itself, small RNA molecules have emerged as key regulators of gene expression and mediators of host-pathogen interactions. Understanding sRNA regulatory networks in mycobacteria can drive our understanding of significant role they play in regulating virulence and adaptation to the host environment. Detailed functional characterization of Mtb sRNAs at the host-pathogen interface is required to fully elucidate the complex sRNA-mediated gene regulatory networks deployed by Mtb, to manipulate the host. A deeper understanding of this aspect could pave the development of novel diagnostic and therapeutic strategies for tuberculosis.
Collapse
Affiliation(s)
- Rajni Garg
- Department of Human Genetics and Molecular Medicine, Amity School of Health Sciences, Amity University, Mohali, Punjab, India
| | - Ishali Manhas
- Department of Biotechnology, Amity School of Biological Sciences, Amity University, Mohali, Punjab, India
| | - Diksha Chaturvedi
- Department of Biotechnology and Medical Engineering, National Institute of Technology, Rourkela, Odisha, India
| |
Collapse
|
4
|
Zhou Y, Sun H, Rapiejko AR, Vargas-Blanco DA, Martini MC, Chase MR, Joubran SR, Davis AB, Dainis JP, Kelly JM, Ioerger TR, Roberts LA, Fortune SM, Shell SS. Mycobacterial RNase E cleaves with a distinct sequence preference and controls the degradation rates of most Mycolicibacterium smegmatis mRNAs. J Biol Chem 2023; 299:105312. [PMID: 37802316 PMCID: PMC10641625 DOI: 10.1016/j.jbc.2023.105312] [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: 03/16/2023] [Revised: 08/29/2023] [Accepted: 09/29/2023] [Indexed: 10/08/2023] Open
Abstract
The mechanisms and regulation of RNA degradation in mycobacteria have been subject to increased interest following the identification of interplay between RNA metabolism and drug resistance. Mycobacteria encode multiple ribonucleases predicted to participate in mRNA degradation and/or processing of stable RNAs. RNase E is hypothesized to play a major role in mRNA degradation because of its essentiality in mycobacteria and its role in mRNA degradation in gram-negative bacteria. Here, we defined the impact of RNase E on mRNA degradation rates transcriptome-wide in the nonpathogenic model Mycolicibacterium smegmatis. RNase E played a rate-limiting role in degradation of the transcripts encoded by at least 89% of protein-coding genes, with leadered transcripts often being more affected by RNase E repression than leaderless transcripts. There was an apparent global slowing of transcription in response to knockdown of RNase E, suggesting that M. smegmatis regulates transcription in responses to changes in mRNA degradation. This compensation was incomplete, as the abundance of most transcripts increased upon RNase E knockdown. We assessed the sequence preferences for cleavage by RNase E transcriptome-wide in M. smegmatis and Mycobacterium tuberculosis and found a consistent bias for cleavage in C-rich regions. Purified RNase E had a clear preference for cleavage immediately upstream of cytidines, distinct from the sequence preferences of RNase E in gram-negative bacteria. We furthermore report a high-resolution map of mRNA cleavage sites in M. tuberculosis, which occur primarily within the RNase E-preferred sequence context, confirming that RNase E has a broad impact on the M. tuberculosis transcriptome.
Collapse
Affiliation(s)
- Ying Zhou
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Huaming Sun
- Program in Bioinformatics and Computational Biology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Abigail R Rapiejko
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Diego A Vargas-Blanco
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Maria Carla Martini
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Michael R Chase
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Samantha R Joubran
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Alexa B Davis
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Joseph P Dainis
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Jessica M Kelly
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Thomas R Ioerger
- Department of Computer Science & Engineering, Texas A&M University, College Station, Texas, USA
| | - Louis A Roberts
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Sarah M Fortune
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Scarlet S Shell
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, USA.
| |
Collapse
|
5
|
Wiegard JC, Damm K, Lechner M, Thölken C, Ngo S, Putzer H, Hartmann RK. Processing and decay of 6S-1 and 6S-2 RNAs in Bacillus subtilis. RNA (NEW YORK, N.Y.) 2023; 29:1481-1499. [PMID: 37369528 PMCID: PMC10578484 DOI: 10.1261/rna.079666.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023]
Abstract
Noncoding 6S RNAs regulate transcription by binding to the active site of bacterial RNA polymerase holoenzymes. Processing and decay of 6S-1 and 6S-2 RNA were investigated in Bacillus subtilis by northern blot and RNA-seq analyses using different RNase knockout strains, as well as by in vitro processing assays. For both 6S RNA paralogs, we identified a key-but mechanistically different-role of RNase J1. RNase J1 catalyzes 5'-end maturation of 6S-1 RNA, yet relatively inefficient and possibly via the enzyme's "sliding endonuclease" activity. 5'-end maturation has no detectable effect on 6S-1 RNA function, but rather regulates its decay: The generated 5'-monophosphate on matured 6S-1 RNA propels endonucleolytic cleavage in its apical loop region. The major 6S-2 RNA degradation pathway is initiated by endonucleolytic cleavage in the 5'-central bubble to trigger 5'-to-3'-exoribonucleolytic degradation of the downstream fragment by RNase J1. The four 3'-exonucleases of B. subtilis-RNase R, PNPase, YhaM, and particularly RNase PH-are involved in 3'-end trimming of both 6S RNAs, degradation of 6S-1 RNA fragments, and decay of abortive transcripts (so-called product RNAs, ∼14 nt in length) synthesized on 6S-1 RNA during outgrowth from stationary phase. In the case of the growth-retarded RNase Y deletion strain, we were unable to infer a specific role of RNase Y in 6S RNA decay. Yet, a participation of RNase Y in 6S RNA decay still remains possible, as evidence for such a function may have been obscured by overlapping substrate specificities of RNase Y, RNase J1, and RNase J2.
Collapse
Affiliation(s)
- Jana Christin Wiegard
- Philipps-Universität Marburg, Institut für Pharmazeutische Chemie, D-35037 Marburg, Germany
| | - Katrin Damm
- Philipps-Universität Marburg, Institut für Pharmazeutische Chemie, D-35037 Marburg, Germany
| | - Marcus Lechner
- Philipps-Universität Marburg, Center for Synthetic Microbiology (SYNMIKRO), Bioinformatics Core Facility, D-35032 Marburg, Germany
| | - Clemens Thölken
- Philipps-Universität Marburg, Center for Synthetic Microbiology (SYNMIKRO), Bioinformatics Core Facility, D-35032 Marburg, Germany
| | - Saravuth Ngo
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France
| | - Harald Putzer
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France
| | - Roland K Hartmann
- Philipps-Universität Marburg, Institut für Pharmazeutische Chemie, D-35037 Marburg, Germany
| |
Collapse
|
6
|
Jia H, Dantuluri S, Margulies S, Smith V, Lever R, Allers T, Koh J, Chen S, Maupin-Furlow JA. RecJ3/4-aRNase J form a Ubl-associated nuclease complex functioning in survival against DNA damage in Haloferax volcanii. mBio 2023; 14:e0085223. [PMID: 37458473 PMCID: PMC10470531 DOI: 10.1128/mbio.00852-23] [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: 04/05/2023] [Accepted: 06/02/2023] [Indexed: 09/02/2023] Open
Abstract
Nucleases are strictly regulated and often localized in the cell to avoid the uncontrolled degradation of DNA and RNA. Here, a new type of nuclease complex, composed of RecJ3, RecJ4, and aRNase J, was identified through its ATP-dependent association with the ubiquitin-like SAMP1 and AAA-ATPase Cdc48a. The complex was discovered in Haloferax volcanii, an archaeon lacking an RNA exosome. Genetic analysis revealed aRNase J to be essential and RecJ3, RecJ4, and Cdc48a to function in the recovery from DNA damage including genotoxic agents that generate double-strand breaks. The RecJ3:RecJ4:aRNase J complex (isolated in 2:2:1 stoichiometry) functioned primarily as a 3'-5' exonuclease in hydrolyzing RNA and ssDNA, with the mechanism non-processive for ssDNA. aRNase J could also be purified as a homodimer that catalyzed endoribonuclease activity and, thus, was not restricted to the 5'-3' exonuclease activity typical of aRNase J homologs. Moreover, RecJ3 and RecJ4 could be purified as a 560-kDa subcomplex in equimolar subunit ratio with nuclease activities mirroring the full RecJ3/4-aRNase J complex. These findings prompted reconstitution assays that suggested RecJ3/4 could suppress, alter, and/or outcompete the nuclease activities of aRNase J. Based on the phenotypic results, this control mechanism of aRNase J by RecJ3/4 is not necessary for cell growth but instead appears important for DNA repair. IMPORTANCE Nucleases are critical for various cellular processes including DNA replication and repair. Here, a dynamic type of nuclease complex is newly identified in the archaeon Haloferax volcanii, which is missing the canonical RNA exosome. The complex, composed of RecJ3, RecJ4, and aRNase J, functions primarily as a 3'-5' exonuclease and was discovered through its ATP-dependent association with the ubiquitin-like SAMP1 and Cdc48a. aRNase J alone forms a homodimer that has endonuclease function and, thus, is not restricted to 5'-3' exonuclease activity typical of other aRNase J enzymes. RecJ3/4 appears to suppress, alter, and/or outcompete the nuclease activities of aRNase J. While aRNase J is essential for growth, RecJ3/4, Cdc48a, and SAMPs are important for recovery against DNA damage. These biological distinctions may correlate with the regulated nuclease activity of aRNase J in the RecJ3/4-aRNaseJ complex.
Collapse
Affiliation(s)
- Huiyong Jia
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Science, University of Florida, Gainesville, Florida, USA
| | - Swathi Dantuluri
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Science, University of Florida, Gainesville, Florida, USA
| | - Shae Margulies
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Science, University of Florida, Gainesville, Florida, USA
| | - Victoria Smith
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Rebecca Lever
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Thorsten Allers
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Jin Koh
- Proteomics and Mass Spectrometry, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida, USA
| | - Sixue Chen
- Proteomics and Mass Spectrometry, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida, USA
- Genetics Institute, University of Florida, Gainesville, Florida, USA
- Department of Biology, College of Liberal Arts and Sciences, University of Florida, Gainesville, Florida, USA
| | - Julie A. Maupin-Furlow
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Science, University of Florida, Gainesville, Florida, USA
- Genetics Institute, University of Florida, Gainesville, Florida, USA
| |
Collapse
|
7
|
Wang N, Li P, Cheng Y, Song H, Xu C. Stem-loop structures control mRNA processing of the cellulosomal cip-cel operon in Ruminiclostridium cellulolyticum. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:106. [PMID: 37386549 DOI: 10.1186/s13068-023-02357-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 06/11/2023] [Indexed: 07/01/2023]
Abstract
BACKGROUND Anaerobic, mesophilic, and cellulolytic Ruminiclostridium cellulolyticum produces an efficient cellulolytic extracellular complex named cellulosome, which consist of a non-catalytic multi-functional integrating subunit, organizing the various catalytic subunits into the complex. Main components of cellulosome were encoded by the cip-cel operon in R. cellulolyticum, and their stoichiometry is controlled by the mechanism of selective RNA processing and stabilization, which allows to confer each processed RNA portion from the cip-cel mRNA on different fates due to their stability and resolve the potential contradiction between the equimolar stoichiometry of transcripts with a within a transcription unit and the non-equimolar stoichiometry of subunits. RESULTS In this work, RNA processing events were found to occur at six intergenic regions (IRs) harboring stem-loop structures in cip-cel operon. These stem-loops not only stabilize processed transcripts at their both ends, but also act as cleavage signals specifically recognized by endoribonucleases. We further demonstrated that cleavage sites were often located downstream or 3' end of their associated stem-loops that could be classified into two types, with distinct GC-rich stems being required for RNA cleavage. However, the cleavage site in IR4 was found to be located upstream of the stem-loop, as determined by the bottom AT-pair region of this stem-loop, together with its upstream structure. Thus, our findings reveal the structural requirements for processing of cip-cel transcripts, which can be potentially used to control the stoichiometry of gene expression in an operon. CONCLUSIONS Our findings reveal that stem-loop structures acting as RNA cleavage signals not only can be recognized by endoribonucleases and determine the location of cleavage sites but also determine the stoichiometry of their flanking processed transcripts by controlling stability in cip-cel operon. These features represent a complexed regulation of cellulosome in the post-transcriptional level, which can be exploited for designing synthetic elements to control gene expression.
Collapse
Affiliation(s)
- Na Wang
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, College of Animal Science and Technology & College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, 030006, Shanxi, China
| | - Ping Li
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, 030006, Shanxi, China
| | - Ying Cheng
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, 030006, Shanxi, China
| | - Houhui Song
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, College of Animal Science and Technology & College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China.
| | - Chenggang Xu
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, College of Animal Science and Technology & College of Veterinary Medicine, Zhejiang A&F University, Hangzhou, 311300, Zhejiang, China.
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, 030006, Shanxi, China.
| |
Collapse
|
8
|
Korobeinikova A, Laalami S, Berthy C, Putzer H. RNase Y Autoregulates Its Synthesis in Bacillus subtilis. Microorganisms 2023; 11:1374. [PMID: 37374876 DOI: 10.3390/microorganisms11061374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/18/2023] [Accepted: 05/22/2023] [Indexed: 06/29/2023] Open
Abstract
The instability of messenger RNA is crucial to the control of gene expression. In Bacillus subtilis, RNase Y is the major decay-initiating endoribonuclease. Here, we show how this key enzyme regulates its own synthesis by modulating the longevity of its mRNA. Autoregulation is achieved through cleavages in two regions of the rny (RNase Y) transcript: (i) within the first ~100 nucleotides of the open reading frame, immediately inactivating the mRNA for further rounds of translation; (ii) cleavages in the rny 5' UTR, primarily within the 5'-terminal 50 nucleotides, creating entry sites for the 5' exonuclease J1 whose progression is blocked around position -15 of the rny mRNA, potentially by initiating ribosomes. This links the functional inactivation of the transcript by RNase J1 to translation efficiency, depending on the ribosome occupancy at the translation initiation site. By these mechanisms, RNase Y can initiate degradation of its own mRNA when the enzyme is not occupied with degradation of other RNAs and thus prevent its overexpression beyond the needs of RNA metabolism.
Collapse
Affiliation(s)
- Anna Korobeinikova
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique, CNRS, Université Paris Cité, 75005 Paris, France
| | - Soumaya Laalami
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique, CNRS, Université Paris Cité, 75005 Paris, France
| | - Clément Berthy
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique, CNRS, Université Paris Cité, 75005 Paris, France
- Inovarion, 75005 Paris, France
| | - Harald Putzer
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique, CNRS, Université Paris Cité, 75005 Paris, France
| |
Collapse
|
9
|
Payá G, Bautista V, Camacho M, Esclapez J, Bonete MJ. Comprehensive Bioinformatics Analysis of the Biodiversity of Lsm Proteins in the Archaea Domain. Microorganisms 2023; 11:1196. [PMID: 37317170 DOI: 10.3390/microorganisms11051196] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/25/2023] [Accepted: 04/27/2023] [Indexed: 06/16/2023] Open
Abstract
The Sm protein superfamily includes Sm, like-Sm (Lsm), and Hfq proteins. Sm and Lsm proteins are found in the Eukarya and Archaea domains, respectively, while Hfq proteins exist in the Bacteria domain. Even though Sm and Hfq proteins have been extensively studied, archaeal Lsm proteins still require further exploration. In this work, different bioinformatics tools are used to understand the diversity and distribution of 168 Lsm proteins in 109 archaeal species to increase the global understanding of these proteins. All 109 archaeal species analyzed encode one to three Lsm proteins in their genome. Lsm proteins can be classified into two groups based on molecular weight. Regarding the gene environment of lsm genes, many of these genes are located adjacent to transcriptional regulators of the Lrp/AsnC and MarR families, RNA-binding proteins, and ribosomal protein L37e. Notably, only proteins from species of the class Halobacteria conserved the internal and external residues of the RNA-binding site identified in Pyrococcus abyssi, despite belonging to different taxonomic orders. In most species, the Lsm genes show associations with 11 genes: rpl7ae, rpl37e, fusA, flpA, purF, rrp4, rrp41, hel308, rpoD, rpoH, and rpoN. We propose that most archaeal Lsm proteins are related to the RNA metabolism, and the larger Lsm proteins could perform different functions and/or act through other mechanisms of action.
Collapse
Affiliation(s)
- Gloria Payá
- Department of Biochemistry and Molecular Biology and Soil Science and Agricultural Chemistry, Faculty of Science, University of Alicante, Ap 99, 03080 Alicante, Spain
| | - Vanesa Bautista
- Department of Biochemistry and Molecular Biology and Soil Science and Agricultural Chemistry, Faculty of Science, University of Alicante, Ap 99, 03080 Alicante, Spain
| | - Mónica Camacho
- Department of Biochemistry and Molecular Biology and Soil Science and Agricultural Chemistry, Faculty of Science, University of Alicante, Ap 99, 03080 Alicante, Spain
| | - Julia Esclapez
- Department of Biochemistry and Molecular Biology and Soil Science and Agricultural Chemistry, Faculty of Science, University of Alicante, Ap 99, 03080 Alicante, Spain
| | - María-José Bonete
- Department of Biochemistry and Molecular Biology and Soil Science and Agricultural Chemistry, Faculty of Science, University of Alicante, Ap 99, 03080 Alicante, Spain
| |
Collapse
|
10
|
Vandanashree M, Singh AK, Gopal B. Characterization of RNase J. Methods Enzymol 2023; 692:177-215. [PMID: 37925179 DOI: 10.1016/bs.mie.2023.03.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2023]
Abstract
RNase J is involved in RNA maturation as well as degradation of RNA to the level of mononucleotides. This enzyme plays a vital role in maintaining intracellular RNA levels and governs different steps of the cellular metabolism in bacteria. RNase J is the first ribonuclease that was shown to have both endonuclease and 5'-3' exonuclease activity. RNase J enzymes can be identified by their characteristic sequence features and domain architecture. The quaternary structure of RNase J plays a role in regulating enzyme activity. The structure of RNase J has been characterized from several homologs. These reveal extensive overall structural similarity alongside a distinct active site topology that coordinates a metal cofactor. The metal cofactor is essential for catalytic activity. The catalytic activity of RNase J is influenced by oligomerization, the choice and stoichiometry of metal cofactors, and the 5' phosphorylation state of the RNA substrate. Here we describe the sequence and structural features of RNase J alongside phylogenetic analysis and reported functional roles in diverse organisms. We also provide a detailed purification strategy to obtain an RNase J enzyme sample with or without a metal cofactor. Different methods to identify the nature of the bound metal cofactor, the binding affinity and stoichiometry are presented. Finally, we describe enzyme assays to characterize RNase J using radioactive and fluorescence-based strategies with diverse RNA substrates.
Collapse
Affiliation(s)
- Muralidharan Vandanashree
- Molecular Biophysics Unit, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Ankur Kumar Singh
- Molecular Biophysics Unit, Division of Biological Sciences, Indian Institute of Science, Bangalore, India
| | - Balasubramanian Gopal
- Molecular Biophysics Unit, Division of Biological Sciences, Indian Institute of Science, Bangalore, India.
| |
Collapse
|
11
|
De Capitani J, Mutschler H. The Long Road to a Synthetic Self-Replicating Central Dogma. Biochemistry 2023; 62:1221-1232. [PMID: 36944355 PMCID: PMC10077596 DOI: 10.1021/acs.biochem.3c00023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
The construction of a biochemical system capable of self-replication is a key objective in bottom-up synthetic biology. Throughout the past two decades, a rapid progression in the design of in vitro cell-free systems has provided valuable insight into the requirements for the development of a minimal system capable of self-replication. The main limitations of current systems can be attributed to their macromolecular composition and how the individual macromolecules use the small molecules necessary to drive RNA and protein synthesis. In this Perspective, we discuss the recent steps that have been taken to generate a minimal cell-free system capable of regenerating its own macromolecular components and maintaining the homeostatic balance between macromolecular biogenesis and consumption of primary building blocks. By following the flow of biological information through the central dogma, we compare the current versions of these systems to date and propose potential alterations aimed at designing a model system for self-replicative synthetic cells.
Collapse
Affiliation(s)
- Jacopo De Capitani
- Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| | - Hannes Mutschler
- Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| |
Collapse
|
12
|
Jones GH. Streptomyces RNases - Function and impact on antibiotic synthesis. Front Microbiol 2023; 14:1096228. [PMID: 37113221 PMCID: PMC10126417 DOI: 10.3389/fmicb.2023.1096228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 03/20/2023] [Indexed: 04/29/2023] Open
Abstract
Streptomyces are soil dwelling bacteria that are notable for their ability to sporulate and to produce antibiotics and other secondary metabolites. Antibiotic biosynthesis is controlled by a variety of complex regulatory networks, involving activators, repressors, signaling molecules and other regulatory elements. One group of enzymes that affects antibiotic synthesis in Streptomyces is the ribonucleases. In this review, the function of five ribonucleases, RNase E, RNase J, polynucleotide phosphorylase, RNase III and oligoribonuclease, and their impact on antibiotic production will be discussed. Mechanisms for the effects of RNase action on antibiotic synthesis are proposed.
Collapse
|
13
|
Martini MC, Hicks ND, Xiao J, Alonso MN, Barbier T, Sixsmith J, Fortune SM, Shell SS. Loss of RNase J leads to multi-drug tolerance and accumulation of highly structured mRNA fragments in Mycobacterium tuberculosis. PLoS Pathog 2022; 18:e1010705. [PMID: 35830479 PMCID: PMC9312406 DOI: 10.1371/journal.ppat.1010705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 07/25/2022] [Accepted: 06/27/2022] [Indexed: 11/24/2022] Open
Abstract
Despite the existence of well-characterized, canonical mutations that confer high-level drug resistance to Mycobacterium tuberculosis (Mtb), there is evidence that drug resistance mechanisms are more complex than simple acquisition of such mutations. Recent studies have shown that Mtb can acquire non-canonical resistance-associated mutations that confer survival advantages in the presence of certain drugs, likely acting as stepping-stones for acquisition of high-level resistance. Rv2752c/rnj, encoding RNase J, is disproportionately mutated in drug-resistant clinical Mtb isolates. Here we show that deletion of rnj confers increased tolerance to lethal concentrations of several drugs. RNAseq revealed that RNase J affects expression of a subset of genes enriched for PE/PPE genes and stable RNAs and is key for proper 23S rRNA maturation. Gene expression differences implicated two sRNAs and ppe50-ppe51 as important contributors to the drug tolerance phenotype. In addition, we found that in the absence of RNase J, many short RNA fragments accumulate because they are degraded at slower rates. We show that the accumulated transcript fragments are targets of RNase J and are characterized by strong secondary structure and high G+C content, indicating that RNase J has a rate-limiting role in degradation of highly structured RNAs. Taken together, our results demonstrate that RNase J indirectly affects drug tolerance, as well as reveal the endogenous roles of RNase J in mycobacterial RNA metabolism.
Collapse
Affiliation(s)
- Maria Carla Martini
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| | - Nathan D. Hicks
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Junpei Xiao
- Program in Bioinformatics and Computational Biology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| | - Maria Natalia Alonso
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| | - Thibault Barbier
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Jaimie Sixsmith
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Sarah M. Fortune
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Scarlet S. Shell
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
- Program in Bioinformatics and Computational Biology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| |
Collapse
|
14
|
Zhang J, Hess WR, Zhang C. "Life is short, and art is long": RNA degradation in cyanobacteria and model bacteria. MLIFE 2022; 1:21-39. [PMID: 38818322 PMCID: PMC10989914 DOI: 10.1002/mlf2.12015] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/03/2022] [Accepted: 03/03/2022] [Indexed: 06/01/2024]
Abstract
RNA turnover plays critical roles in the regulation of gene expression and allows cells to respond rapidly to environmental changes. In bacteria, the mechanisms of RNA turnover have been extensively studied in the models Escherichia coli and Bacillus subtilis, but not much is known in other bacteria. Cyanobacteria are a diverse group of photosynthetic organisms that have great potential for the sustainable production of valuable products using CO2 and solar energy. A better understanding of the regulation of RNA decay is important for both basic and applied studies of cyanobacteria. Genomic analysis shows that cyanobacteria have more than 10 ribonucleases and related proteins in common with E. coli and B. subtilis, and only a limited number of them have been experimentally investigated. In this review, we summarize the current knowledge about these RNA-turnover-related proteins in cyanobacteria. Although many of them are biochemically similar to their counterparts in E. coli and B. subtilis, they appear to have distinct cellular functions, suggesting a different mechanism of RNA turnover regulation in cyanobacteria. The identification of new players involved in the regulation of RNA turnover and the elucidation of their biological functions are among the future challenges in this field.
Collapse
Affiliation(s)
- Ju‐Yuan Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology and Key Laboratory of Algal Biology, Institute of HydrobiologyChinese Academy of SciencesWuhanChina
| | - Wolfgang R. Hess
- Genetics and Experimental Bioinformatics, Faculty of BiologyUniversity of FreiburgFreiburgGermany
| | - Cheng‐Cai Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology and Key Laboratory of Algal Biology, Institute of HydrobiologyChinese Academy of SciencesWuhanChina
- Institut WUT‐AMUAix‐Marseille University and Wuhan University of TechnologyWuhanChina
| |
Collapse
|
15
|
Waters SM, Robles-Martínez JA, Nicholson WL. Growth at 5 kPa Causes Differential Expression of a Number of Signals in a Bacillus subtilis Strain Adapted to Enhanced Growth at Low Pressure. ASTROBIOLOGY 2021; 21:1076-1088. [PMID: 34357782 DOI: 10.1089/ast.2020.2389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
To determine microbial evolutionary strategies to low-pressure (LP; 5 kPa) growth, an environmental condition not experienced on Earth until ∼20 km in altitude, a previously described evolutionary experiment was conducted. The resulting LP evolved strain WN1106, isolated from the terminus of the experiment, was shown to have several genomic mutations absent in the ancestral strain, WN624. Three of the mutations were in regulatory genes: resD, walK, and rnjB. Here we report on transcriptional microarray data from the LP-evolved WN1106 and compare those results with the previously reported ancestral WN624 transcriptional array data at either 5 or 101 kPa. At 5 kPa, WN1106 differentially expresses signals that are under the control of regulators ResD, WalK, and RnjB compared with (1) itself at ∼101 kPa and (2) WN624 at 5 kPa. These results were further confirmed by quantitative reverse transcriptase-polymerase chain reaction of a target transcript from each regulon. This work indicates that the three mutated coding regions had transcriptional control effects on each respective regulon.
Collapse
Affiliation(s)
- Samantha M Waters
- Universities Space Research Association, Washington, DC, USA
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, California, USA
- Space Life Sciences Lab, Department of Microbiology and Cell Science, University of Florida, Kennedy Space Center, Florida, USA
| | - José A Robles-Martínez
- Space Life Sciences Lab, Department of Microbiology and Cell Science, University of Florida, Kennedy Space Center, Florida, USA
| | - Wayne L Nicholson
- Space Life Sciences Lab, Department of Microbiology and Cell Science, University of Florida, Kennedy Space Center, Florida, USA
| |
Collapse
|
16
|
Machado de Amorim A, Chakrabarti S. Assembly of multicomponent machines in RNA metabolism: A common theme in mRNA decay pathways. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 13:e1684. [PMID: 34351053 DOI: 10.1002/wrna.1684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/07/2021] [Accepted: 07/08/2021] [Indexed: 11/05/2022]
Abstract
Multicomponent protein-RNA complexes comprising a ribonuclease and partner RNA helicase facilitate the turnover of mRNA in all domains of life. While these higher-order complexes provide an effective means of physically and functionally coupling the processes of RNA remodeling and decay, most ribonucleases and RNA helicases do not exhibit sequence specificity in RNA binding. This raises the question as to how these assemblies select substrates for processing and how the activities are orchestrated at the precise moment to ensure efficient decay. The answers to these apparent puzzles lie in the auxiliary components of the assemblies that might relay decay-triggering signals. Given their function within the assemblies, these components may be viewed as "sensors." The functions and mechanisms of action of the sensor components in various degradation complexes in bacteria and eukaryotes are highlighted here to discuss their roles in RNA decay processes. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition.
Collapse
Affiliation(s)
| | - Sutapa Chakrabarti
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| |
Collapse
|
17
|
Laalami S, Cavaiuolo M, Roque S, Chagneau C, Putzer H. Escherichia coli RNase E can efficiently replace RNase Y in Bacillus subtilis. Nucleic Acids Res 2021; 49:4643-4654. [PMID: 33788929 PMCID: PMC8096251 DOI: 10.1093/nar/gkab216] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/11/2021] [Accepted: 03/17/2021] [Indexed: 02/06/2023] Open
Abstract
RNase Y and RNase E are disparate endoribonucleases that govern global mRNA turnover/processing in the two evolutionary distant bacteria Bacillus subtilis and Escherichia coli, respectively. The two enzymes share a similar in vitro cleavage specificity and subcellular localization. To evaluate the potential equivalence in biological function between the two enzymes in vivo we analyzed whether and to what extent RNase E is able to replace RNase Y in B. subtilis. Full-length RNase E almost completely restores wild type growth of the rny mutant. This is matched by a surprising reversal of transcript profiles both of individual genes and on a genome-wide scale. The single most important parameter to efficient complementation is the requirement for RNase E to localize to the inner membrane while truncation of the C-terminal sequences corresponding to the degradosome scaffold has only a minor effect. We also compared the in vitro cleavage activity for the major decay initiating ribonucleases Y, E and J and show that no conclusions can be drawn with respect to their activity in vivo. Our data confirm the notion that RNase Y and RNase E have evolved through convergent evolution towards a low specificity endonuclease activity universally important in bacteria.
Collapse
Affiliation(s)
- Soumaya Laalami
- CNRS, UMR8261, Institut de Biologie Physico-Chimique, Université de Paris, 75005 Paris, France
| | - Marina Cavaiuolo
- CNRS, UMR8261, Institut de Biologie Physico-Chimique, Université de Paris, 75005 Paris, France
| | - Sylvain Roque
- CNRS, UMR8261, Institut de Biologie Physico-Chimique, Université de Paris, 75005 Paris, France
| | - Carine Chagneau
- CNRS, UMR8261, Institut de Biologie Physico-Chimique, Université de Paris, 75005 Paris, France
| | - Harald Putzer
- CNRS, UMR8261, Institut de Biologie Physico-Chimique, Université de Paris, 75005 Paris, France
| |
Collapse
|
18
|
Moonlighting in Bacillus subtilis: The Small Proteins SR1P and SR7P Regulate the Moonlighting Activity of Glyceraldehyde 3-Phosphate Dehydrogenase A (GapA) and Enolase in RNA Degradation. Microorganisms 2021; 9:microorganisms9051046. [PMID: 34066298 PMCID: PMC8152036 DOI: 10.3390/microorganisms9051046] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 12/21/2022] Open
Abstract
Moonlighting proteins are proteins with more than one function. During the past 25 years, they have been found to be rather widespread in bacteria. In Bacillus subtilis, moonlighting has been disclosed to occur via DNA, protein or RNA binding or protein phosphorylation. In addition, two metabolic enzymes, enolase and phosphofructokinase, were localized in the degradosome-like network (DLN) where they were thought to be scaffolding components. The DLN comprises the major endoribonuclease RNase Y, 3'-5' exoribonuclease PnpA, endo/5'-3' exoribonucleases J1/J2 and helicase CshA. We have ascertained that the metabolic enzyme GapA is an additional component of the DLN. In addition, we identified two small proteins that bind scaffolding components of the degradosome: SR1P encoded by the dual-function sRNA SR1 binds GapA, promotes the GapA-RNase J1 interaction and increases the RNase J1 activity. SR7P encoded by the dual-function antisense RNA SR7 binds to enolase thereby enhancing the enzymatic activity of enolase bound RNase Y. We discuss the role of small proteins in modulating the activity of two moonlighting proteins.
Collapse
|
19
|
Liu TY, Tsai SH, Chen JW, Wang YC, Hu ST, Chen YY. Mab_3083c Is a Homologue of RNase J and Plays a Role in Colony Morphotype, Aggregation, and Sliding Motility of Mycobacterium abscessus. Microorganisms 2021; 9:microorganisms9040676. [PMID: 33805851 PMCID: PMC8064342 DOI: 10.3390/microorganisms9040676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/14/2021] [Accepted: 03/19/2021] [Indexed: 12/17/2022] Open
Abstract
Mycobacterium abscessus is an opportunistic pathogen causing human diseases, especially in immunocompromised patients. M. abscessus strains with a rough morphotype are more virulent than those with a smooth morphotype. Morphotype switch may occur during a clinical infection. To investigate the genes involved in colony morphotype switching, we performed transposon mutagenesis in a rough clinical strain of M. abscessus. A morphotype switching mutant (smooth) named mab_3083c::Tn was obtained. This mutant was found to have a lower aggregative ability and a higher sliding motility than the wild type strain. However, its glycopeptidolipid (GPL) content remained the same as those of the wild type. Complementation of the mutant with a functional mab_3083c gene reverted its morphotype back to rough, indicating that mab_3083c is associated with colony morphology of M. abscessus. Bioinformatic analyses showed that mab_3083c has a 75.4% identity in amino acid sequence with the well-characterized ribonuclease J (RNase J) of M. smegmatis (RNase JMsmeg). Complementation of the mutant with the RNase J gene of M. smegmatis also switched its colony morphology from smooth back to rough. These results suggest that Mab_3083c is a homologue of RNase J and involved in regulating M. abscessus colony morphotype switching.
Collapse
Affiliation(s)
- Ting-Yu Liu
- Institute of Microbiology and Immunology, School of Life Science, National Yang-Ming University, Taipei 112, Taiwan; (T.-Y.L.); (S.-H.T.)
| | - Sheng-Hui Tsai
- Institute of Microbiology and Immunology, School of Life Science, National Yang-Ming University, Taipei 112, Taiwan; (T.-Y.L.); (S.-H.T.)
| | - Jenn-Wei Chen
- Department of Microbiology and Immunology, College of Medicine, National Cheng-Kung University, Tainan 701, Taiwan;
- Institute of Basic Medical Sciences, College of Medicine, National Cheng-Kung University, Tainan 701, Taiwan
| | - Yu-Ching Wang
- Department of Biochemical Science and Technology, National Chiayi Univeristy, Chiayi City 600, Taiwan;
| | - Shiau-Ting Hu
- Institute of Microbiology and Immunology, School of Life Science, National Yang-Ming University, Taipei 112, Taiwan; (T.-Y.L.); (S.-H.T.)
- Correspondence: (S.-T.H.); (Y.-Y.C.)
| | - Yih-Yuan Chen
- Department of Biochemical Science and Technology, National Chiayi Univeristy, Chiayi City 600, Taiwan;
- Correspondence: (S.-T.H.); (Y.-Y.C.)
| |
Collapse
|
20
|
Aroonsri A, Kongsee J, Gunawan JD, Aubry DA, Shaw PJ. A cell-based ribozyme reporter system employing a chromosomally-integrated 5' exonuclease gene. BMC Mol Cell Biol 2021; 22:20. [PMID: 33726662 PMCID: PMC7967978 DOI: 10.1186/s12860-021-00357-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 02/28/2021] [Indexed: 11/10/2022] Open
Abstract
Background Bioinformatic genome surveys indicate that self-cleaving ribonucleic acids (ribozymes) appear to be widespread among all domains of life, although the functions of only a small number have been validated by biochemical methods. Alternatively, cell-based reporter gene assays can be used to validate ribozyme function. However, reporter activity can be confounded by phenomena unrelated to ribozyme-mediated cleavage of RNA. Results We established a ribozyme reporter system in Escherichia coli in which a significant reduction of reporter activity is manifest when an active ribozyme sequence is fused to the reporter gene and the expression of a foreign Bacillus subtilis RNaseJ1 5′ exonuclease is induced from a chromosomally-integrated gene in the same cell. Conclusions The reporter system could be useful for validating ribozyme function in candidate sequences identified from bioinformatics. Supplementary Information The online version contains supplementary material available at 10.1186/s12860-021-00357-7.
Collapse
Affiliation(s)
- Aiyada Aroonsri
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand.
| | - Jindaporn Kongsee
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand
| | - Jeremy David Gunawan
- School of Life Science, Indonesia International Institute for Life Sciences (i3L), Jakarta, 13210, Indonesia
| | - Daniel Abidin Aubry
- School of Life Science, Indonesia International Institute for Life Sciences (i3L), Jakarta, 13210, Indonesia
| | - Philip James Shaw
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand
| |
Collapse
|
21
|
Ribonuclease J-Mediated mRNA Turnover Modulates Cell Shape, Metabolism and Virulence in Corynebacterium diphtheriae. Microorganisms 2021; 9:microorganisms9020389. [PMID: 33672886 PMCID: PMC7917786 DOI: 10.3390/microorganisms9020389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 01/16/2023] Open
Abstract
Controlled RNA degradation is a crucial process in bacterial cell biology for maintaining proper transcriptome homeostasis and adaptation to changing environments. mRNA turnover in many Gram-positive bacteria involves a specialized ribonuclease called RNase J (RnJ). To date, however, nothing is known about this process in the diphtheria-causative pathogen Corynebacterium diphtheriae, nor is known the identity of this ribonuclease in this organism. Here, we report that C. diphtheriae DIP1463 encodes a predicted RnJ homolog, comprised of a conserved N-terminal β-lactamase domain, followed by β-CASP and C-terminal domains. A recombinant protein encompassing the β-lactamase domain alone displays 5'-exoribonuclease activity, which is abolished by alanine-substitution of the conserved catalytic residues His186 and His188. Intriguingly, deletion of DIP1463/rnj in C. diphtheriae reduces bacterial growth and generates cell shape abnormality with markedly augmented cell width. Comparative RNA-seq analysis revealed that RnJ controls a large regulon encoding many factors predicted to be involved in biosynthesis, regulation, transport, and iron acquisition. One upregulated gene in the ∆rnj mutant is ftsH, coding for a membrane protease (FtsH) involved in cell division, whose overexpression in the wild-type strain also caused cell-width augmentation. Critically, the ∆rnj mutant is severely attenuated in virulence in a Caenorhabditis elegans model of infection, while the FtsH-overexpressing and toxin-less strains exhibit full virulence as the wild-type strain. Evidently, RNase J is a key ribonuclease in C. diphtheriae that post-transcriptionally influences the expression of numerous factors vital to corynebacterial cell physiology and virulence. Our findings have significant implications for basic biological processes and mechanisms of corynebacterial pathogenesis.
Collapse
|
22
|
Corsi ID, Dutta S, van Hoof A, Koehler TM. AtxA-Controlled Small RNAs of Bacillus anthracis Virulence Plasmid pXO1 Regulate Gene Expression in trans. Front Microbiol 2021; 11:610036. [PMID: 33519762 PMCID: PMC7843513 DOI: 10.3389/fmicb.2020.610036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/11/2020] [Indexed: 11/13/2022] Open
Abstract
Small regulatory RNAs (sRNAs) are short transcripts that base-pair to mRNA targets or interact with regulatory proteins. sRNA function has been studied extensively in Gram-negative bacteria; comparatively less is known about sRNAs in Firmicutes. Here we investigate two sRNAs encoded by virulence plasmid pXO1 of Bacillus anthracis, the causative agent of anthrax. The sRNAs, named “XrrA and XrrB” (for pXO1-encoded regulatory RNA) are abundant and highly stable primary transcripts, whose expression is dependent upon AtxA, the master virulence regulator of B. anthracis. sRNA levels are highest during culture conditions that promote AtxA expression and activity, and sRNA levels are unaltered in Hfq RNA chaperone null-mutants. Comparison of the transcriptome of a virulent Ames-derived strain to the transcriptome of isogenic sRNA-null mutants revealed multiple 4.0- to >100-fold differences in gene expression. Most regulatory effects were associated with XrrA, although regulation of some transcripts suggests functional overlap between the XrrA and XrrB. Many sRNA-regulated targets were chromosome genes associated with branched-chain amino acid metabolism, proteolysis, and transmembrane transport. Finally, in a mouse model for systemic anthrax, the lungs and livers of animals infected with xrrA-null mutants had a small reduction in bacterial burden, suggesting a role for XrrA in B. anthracis pathogenesis.
Collapse
Affiliation(s)
- Ileana D Corsi
- Department of Microbiology and Molecular Genetics, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States.,MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, The University of Texas, Houston, TX, United States
| | - Soumita Dutta
- Department of Microbiology and Molecular Genetics, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Ambro van Hoof
- Department of Microbiology and Molecular Genetics, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States.,MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, The University of Texas, Houston, TX, United States
| | - Theresa M Koehler
- Department of Microbiology and Molecular Genetics, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States.,MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, The University of Texas, Houston, TX, United States
| |
Collapse
|
23
|
Raj R, Nadig S, Patel T, Gopal B. Structural and biochemical characteristics of two Staphylococcus epidermidis RNase J paralogs RNase J1 and RNase J2. J Biol Chem 2020; 295:16863-16876. [PMID: 32994223 PMCID: PMC7864078 DOI: 10.1074/jbc.ra120.014876] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 09/21/2020] [Indexed: 11/06/2022] Open
Abstract
RNase J enzymes are metallohydrolases that are involved in RNA maturation and RNA recycling, govern gene expression in bacteria, and catalyze both exonuclease and endonuclease activity. The catalytic activity of RNase J is regulated by multiple mechanisms which include oligomerization, conformational changes to aid substrate recognition, and the metal cofactor at the active site. However, little is known of how RNase J paralogs differ in expression and activity. Here we describe structural and biochemical features of two Staphylococcus epidermidis RNase J paralogs, RNase J1 and RNase J2. RNase J1 is a homodimer with exonuclease activity aided by two metal cofactors at the active site. RNase J2, on the other hand, has endonuclease activity and one metal ion at the active site and is predominantly a monomer. We note that the expression levels of these enzymes vary across Staphylococcal strains. Together, these observations suggest that multiple interacting RNase J paralogs could provide a strategy for functional improvisation utilizing differences in intracellular concentration, quaternary structure, and distinct active site architecture despite overall structural similarity.
Collapse
Affiliation(s)
- Rishi Raj
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Savitha Nadig
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Twinkal Patel
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | | |
Collapse
|
24
|
Vargas-Blanco DA, Shell SS. Regulation of mRNA Stability During Bacterial Stress Responses. Front Microbiol 2020; 11:2111. [PMID: 33013770 PMCID: PMC7509114 DOI: 10.3389/fmicb.2020.02111] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/11/2020] [Indexed: 12/12/2022] Open
Abstract
Bacteria have a remarkable ability to sense environmental changes, swiftly regulating their transcriptional and posttranscriptional machinery as a response. Under conditions that cause growth to slow or stop, bacteria typically stabilize their transcriptomes in what has been shown to be a conserved stress response. In recent years, diverse studies have elucidated many of the mechanisms underlying mRNA degradation, yet an understanding of the regulation of mRNA degradation under stress conditions remains elusive. In this review we discuss the diverse mechanisms that have been shown to affect mRNA stability in bacteria. While many of these mechanisms are transcript-specific, they provide insight into possible mechanisms of global mRNA stabilization. To that end, we have compiled information on how mRNA fate is affected by RNA secondary structures; interaction with ribosomes, RNA binding proteins, and small RNAs; RNA base modifications; the chemical nature of 5' ends; activity and concentration of RNases and other degradation proteins; mRNA and RNase localization; and the stringent response. We also provide an analysis of reported relationships between mRNA abundance and mRNA stability, and discuss the importance of stress-associated mRNA stabilization as a potential target for therapeutic development.
Collapse
Affiliation(s)
- Diego A Vargas-Blanco
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, United States
| | - Scarlet S Shell
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, United States.,Program in Bioinformatics and Computational Biology, Worcester Polytechnic Institute, Worcester, MA, United States
| |
Collapse
|
25
|
MacIntosh GC, Castandet B. Organellar and Secretory Ribonucleases: Major Players in Plant RNA Homeostasis. PLANT PHYSIOLOGY 2020; 183:1438-1452. [PMID: 32513833 PMCID: PMC7401137 DOI: 10.1104/pp.20.00076] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 05/31/2020] [Indexed: 05/05/2023]
Abstract
Organellar and secretory RNases, associated with different cellular compartments, are essential to maintain cellular homeostasis during development and in stress responses.
Collapse
Affiliation(s)
- Gustavo C MacIntosh
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Benoît Castandet
- Université Paris-Saclay, Centre National de la Recherche Scientifique, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
- Université de Paris, Centre National de la Recherche Scientifique, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Institute of Plant Sciences Paris-Saclay (IPS2), 91405, Orsay, France
| |
Collapse
|
26
|
Muchaamba F, Eshwar AK, von Ah U, Stevens MJA, Tasara T. Evolution of Listeria monocytogenes During a Persistent Human Prosthetic Hip Joint Infection. Front Microbiol 2020; 11:1726. [PMID: 32849369 PMCID: PMC7399150 DOI: 10.3389/fmicb.2020.01726] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 07/01/2020] [Indexed: 11/23/2022] Open
Abstract
Listeria monocytogenes associated prosthetic joint infections (PJI) are a rare but increasing clinical problem of listeriosis. We characterized two isolates of the same L. monocytogenes strain isolated within five years of each other from a recurrent human prosthetic joint infection. The two isolates although clonally identical were phenotypically distinct confirming that the original infection strain had evolved within the human host PJI environment giving rise to a phenotypically distinct variant. The recurrent PJI isolate displayed various phenotypic differences compared to the parental original PJI isolate including diminished growth and carbon source metabolism, as well as altered morphology and increased stress sensitivity. The PJI isolates were both diminished in virulence due to an identical truncation mutation in the major virulence regulator PrfA. Genome wide sequence comparison provided conclusive evidence that the two isolates were identical clonal descendants of the same L. monocytogenes strain that had evolved through acquisition of various single nucleotide polymorphisms (SNPs) as well as insertion and deletion events (InDels) during a persistent human PJI. Acquired genetic changes included a specific mutation causing premature stop codon (PMSC) and truncation of RNAse J1 protein. Based on analysis of this naturally truncated as well as other complete RNAse J1 deletion mutants we show that the long-term survival of this specific L. monocytogenes strain within the prosthetic joint might in part be explained by the rnjA PMSC mutation that diminishes virulence and activation of the host immune system in a zebrafish embryo localized infection model. Overall our analysis of this special natural case provides insights into random mutation events and molecular mechanisms that might be associated with the adaptation and short-term evolution of this specific L. monocytogenes strain within a persistent human PJI environment.
Collapse
Affiliation(s)
- Francis Muchaamba
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Athmanya K. Eshwar
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | | | - Marc J. A. Stevens
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Taurai Tasara
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| |
Collapse
|
27
|
Li J, Hou Y, Gu X, Yue L, Guo L, Li D, Dong X. A newly identified duplex RNA unwinding activity of archaeal RNase J depends on processive exoribonucleolysis coupled steric occlusion by its structural archaeal loops. RNA Biol 2020; 17:1480-1491. [PMID: 32552320 DOI: 10.1080/15476286.2020.1777379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
RNase J is a prokaryotic 5'-3' exo/endoribonuclease that functions in mRNA decay and rRNA maturation. Here, we report a novel duplex unwinding activity of mpy-RNase J, an archaeal RNase J from Methanolobus psychrophilus, which enables it to degrade duplex RNAs with hairpins up to 40 bp when linking a 5' single-stranded overhangs of ≥ 7 nt, corresponding to the RNA channel length. A 6-nt RNA-mpy-RNase J-S247A structure reveals the RNA-interacting residues and a steric barrier at the RNA channel entrance comprising two archaeal loops and two helices. Mutagenesis of the residues key to either exoribonucleolysis or RNA translocation diminished the duplex unwinding activity. Substitution of the residues in the steric barrier yielded stalled degradation intermediates at the duplex RNA regions. Thus, an exoribonucleolysis-driven and steric occlusion-based duplex unwinding mechanism was identified. The duplex unwinding activity confers mpy-RNase J the capability of degrading highly structured RNAs, including the bacterial REP RNA, and archaeal mRNAs, rRNAs, tRNAs, SRPs, RNase P and CD-box RNAs, providing an indicative of the potential key roles of mpy-RNase J in pleiotropic RNA metabolisms. Hydrolysis-coupled duplex unwinding activity was also detected in a bacterial RNase J, which may use a shared but slightly different unwinding mechanism from archaeal RNase Js, indicating that duplex unwinding is a common property of the prokaryotic RNase Js.
Collapse
Affiliation(s)
- Jie Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing, PR China.,Colleges of Life Sciences, University of Chinese Academy of Sciences , Beijing, China
| | - Yanjie Hou
- Institute of Biophysics, Chinese Academy of Sciences , Beijing, PR China
| | - Xien Gu
- School of Basic Medical Sciences, Hubei University of Medicine , Shiyan, China
| | - Lei Yue
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing, PR China.,Colleges of Life Sciences, University of Chinese Academy of Sciences , Beijing, China
| | - Lu Guo
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing, PR China
| | - Defeng Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing, PR China.,Colleges of Life Sciences, University of Chinese Academy of Sciences , Beijing, China
| | - Xiuzhu Dong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing, PR China.,Colleges of Life Sciences, University of Chinese Academy of Sciences , Beijing, China
| |
Collapse
|
28
|
Cavaiuolo M, Chagneau C, Laalami S, Putzer H. Impact of RNase E and RNase J on Global mRNA Metabolism in the Cyanobacterium Synechocystis PCC6803. Front Microbiol 2020; 11:1055. [PMID: 32582060 PMCID: PMC7283877 DOI: 10.3389/fmicb.2020.01055] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 04/29/2020] [Indexed: 01/18/2023] Open
Abstract
mRNA levels result from an equilibrium between transcription and degradation. Ribonucleases (RNases) facilitate the turnover of mRNA, which is an important way of controlling gene expression, allowing the cells to adjust transcript levels to a changing environment. In contrast to the heterotrophic model bacteria Escherichia coli and Bacillus subtilis, RNA decay has not been studied in detail in cyanobacteria. Synechocystis sp. PCC6803 encodes orthologs of both E. coli and B. subtilis RNases, including RNase E and RNase J, respectively. We show that in vitro Sy RNases E and J have an endonucleolytic cleavage specificity that is very similar between them and also compared to orthologous enzymes from E. coli, B. subtilis, and Chlamydomonas. Moreover, Sy RNase J displays a robust 5′-exoribonuclease activity similar to B. subtilis RNase J1, but unlike the evolutionarily related RNase J in chloroplasts. Both nucleases are essential and gene deletions could not be fully segregated in Synechocystis. We generated partially disrupted strains of Sy RNase E and J that were stable enough to allow for their growth and characterization. A transcriptome analysis of these strains partially depleted for RNases E and J, respectively, allowed to observe effects on specific transcripts. RNase E altered the expression of a larger number of chromosomal genes and antisense RNAs compared to RNase J, which rather affects endogenous plasmid encoded transcripts. Our results provide the first description of the main transcriptomic changes induced by the partial depletion of two essential ribonucleases in cyanobacteria.
Collapse
Affiliation(s)
- Marina Cavaiuolo
- UMR 8261, CNRS, Institut de Biologie Physico-Chimique, Université de Paris, Paris, France
| | - Carine Chagneau
- UMR 8261, CNRS, Institut de Biologie Physico-Chimique, Université de Paris, Paris, France
| | - Soumaya Laalami
- UMR 8261, CNRS, Institut de Biologie Physico-Chimique, Université de Paris, Paris, France
| | - Harald Putzer
- UMR 8261, CNRS, Institut de Biologie Physico-Chimique, Université de Paris, Paris, France
| |
Collapse
|
29
|
Wang R, Kong F, Wu H, Hou B, Kang Y, Cao Y, Duan S, Ye J, Zhang H. Complete genome sequence of high-yield strain S. lincolnensis B48 and identification of crucial mutations contributing to lincomycin overproduction. Synth Syst Biotechnol 2020; 5:37-48. [DOI: doi.org/10.1016/j.synbio.2020.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/09/2023] Open
|
30
|
Xiao J, Peng B, Su Z, Liu A, Hu Y, Nomura CT, Chen S, Wang Q. Facilitating Protein Expression with Portable 5'-UTR Secondary Structures in Bacillus licheniformis. ACS Synth Biol 2020; 9:1051-1058. [PMID: 32302094 DOI: 10.1021/acssynbio.9b00355] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The 5'-untranslated region (5'-UTR) of prokaryotic mRNAs plays an essential role in post-transcriptional regulation. Bacillus species, such as Bacillus subtilis and Bacillus licheniformis, have gained considerable attention as microbial cell factories for the production of various valuable chemicals and industrial proteins. In this work, we developed a portable 5'-UTR sequence for enhanced protein output in the industrial strain B. licheniformis DW2. This sequence contains only ∼30 nt and forms a hairpin structure located right before the open reading frame. The optimized Shine-Dalgarno (SD) sequence was presented as a single strand on the loop of the hairpin for better ribosome recognition and recruitment. By optimizing the free energy of folding, this 5'-element could effectively enhance the expression of eGFP by ∼50-fold and showed good adaptability for other target proteins, including RFP, nattokinase, and keratinase. This 5'-UTR could promote the accessibility of both the SD sequence and start codon, leading to improved efficiency of translation initiation. Furthermore, the hairpin structure protected mRNA against 5'-exonucleases, resulting in enhanced mRNA stability. It is well-known that the stable structure at a ribosome binding site (RBS) impedes initiation in Escherichia coli. In this study, we presented a unique structure at a RBS that can effectively enhance protein production, which is an exception of this prevailing concept. By adjusting a single thermodynamic parameter and holding the other factors affecting protein output constant, a series of 5'-UTR elements with different expression strengths could be rationally designed for wide use in Bacillus sp.
Collapse
Affiliation(s)
- Jun Xiao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Bing Peng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Zhaowei Su
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Ankun Liu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Yajing Hu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Christopher T. Nomura
- Department of Chemistry, The State University of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, New York 13210, United States
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Qin Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| |
Collapse
|
31
|
Zhou C, Zhang J, Hu X, Li C, Wang L, Huang Q, Chen W. RNase II binds to RNase E and modulates its endoribonucleolytic activity in the cyanobacterium Anabaena PCC 7120. Nucleic Acids Res 2020; 48:3922-3934. [PMID: 32055835 PMCID: PMC7144899 DOI: 10.1093/nar/gkaa092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 02/03/2020] [Accepted: 02/10/2020] [Indexed: 11/16/2022] Open
Abstract
In Escherichia coli, the endoribonuclease E (RNase E) can recruit several other ribonucleases and regulatory proteins via its noncatalytic domain to form an RNA degradosome that controls cellular RNA turnover. Similar RNA degradation complexes have been found in other bacteria; however, their compositions are varied among different bacterial species. In cyanobacteria, only the exoribonuclease PNPase was shown to bind to the noncatalytic domain of RNase E. Here, we showed that Alr1240, a member of the RNB family of exoribonucleases, could be co-isolated with RNase E from the lysate of the cyanobacterium Anabaena PCC 7120. Enzymatic analysis revealed that Alr1240 is an exoribonuclease II (RNase II), as it only degrades non-structured single-stranded RNA substrates. In contrast to known RNase E-interacting ribonucleases, which bind to the noncatalytic domain of RNase E, the Anabaena RNase II was shown to associate with the catalytic domain of RNase E. Using a strain in which RNase E and RNase II were tagged in situ with GFP and BFP, respectively, we showed that RNase E and RNase II form a compact complex in vivo by a fluorescence resonance energy transfer (FRET) assay. RNase E activity on several synthetic substrates was boosted in the presence of RNase II, suggesting that the activity of RNase E could be regulated by RNase II-RNase E interaction. To our knowledge, Anabaena RNase II is an unusual ribonuclease that interacts with the catalytic domain of RNase E, and it may represent a new type of RNA degradosome and a novel mechanism for regulating the activity of the RNA degradosome. As Anabaena RNase E interacts with RNase II and PNPase via different regions, it is very likely that the three ribonucleases form a large complex and cooperatively regulate RNA metabolism in the cell.
Collapse
Affiliation(s)
- Cong Zhou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Juyuan Zhang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China
| | - Xinyu Hu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Changchang Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Li Wang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Qiaoyun Huang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Wenli Chen
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| |
Collapse
|
32
|
Complete genome sequence of high-yield strain S. lincolnensis B48 and identification of crucial mutations contributing to lincomycin overproduction. Synth Syst Biotechnol 2020; 5:37-48. [PMID: 32322696 PMCID: PMC7160387 DOI: 10.1016/j.synbio.2020.03.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 03/09/2020] [Accepted: 03/13/2020] [Indexed: 02/08/2023] Open
Abstract
The lincosamide family antibiotic lincomycin is a widely used antibacterial pharmaceutical generated by Streptomyces lincolnensis, and the high-yield strain B48 produces 2.5 g/L lincomycin, approximately 30-fold as the wild-type strain NRRL 2936. Here, the genome of S. lincolnensis B48 was completely sequenced, revealing a ~10.0 Mb single chromosome with 71.03% G + C content. Based on the genomic information, lincomycin-related primary metabolism network was constructed and the secondary metabolic potential was analyzed. In order to dissect the overproduction mechanism, a comparative genomic analysis with NRRL 2936 was performed. Three large deletions (LDI-III), one large inverted duplication (LID), one long inversion and 80 small variations (including 50 single nucleotide variations, 13 insertions and 17 deletions) were found in B48 genome. Then several crucial mutants contributing to higher production phenotype were validated. Deleting of a MarR-type regulator-encoding gene slinc377 from LDI, and the whole 24.7 kb LDII in NRRL 2936 enhanced lincomycin titer by 244% and 284%, respectively. Besides, lincomycin production of NRRL 2936 was increased to 7.7-fold when a 71 kb supercluster BGC33 from LDIII was eliminated. As for the duplication region, overexpression of the cluster situated genes lmbB2 and lmbU, as well as two novel transcriptional regulator-encoding genes (slinc191 and slinc348) elevated lincomycin titer by 77%, 75%, 114% and 702%, respectively. Furthermore, three negative correlation genes (slinc6156, slinc4481 and slinc6011) on lincomycin biosynthesis, participating in regulation were found out. And surprisingly, inactivation of RNase J-encoding gene slinc6156 and TPR (tetratricopeptide repeat) domain-containing protein-encoding gene slinc4481 achieved lincomycin titer equivalent to 83% and 68% of B48, respectively, to 22.4 and 18.4-fold compared to NRRL 2936. Therefore, the comparative genomics approach combined with confirmatory experiments identified that large fragment deletion, long sequence duplication, along with several mutations of genes, especially regulator genes, are crucial for lincomycin overproduction.
Collapse
|
33
|
Rosana ARR, Whitford DS, Migur A, Steglich C, Kujat-Choy SL, Hess WR, Owttrim GW. RNA helicase-regulated processing of the Synechocystis rimO-crhR operon results in differential cistron expression and accumulation of two sRNAs. J Biol Chem 2020; 295:6372-6386. [PMID: 32209657 DOI: 10.1074/jbc.ra120.013148] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/19/2020] [Indexed: 12/21/2022] Open
Abstract
The arrangement of functionally-related genes in operons is a fundamental element of how genetic information is organized in prokaryotes. This organization ensures coordinated gene expression by co-transcription. Often, however, alternative genetic responses to specific stress conditions demand the discoordination of operon expression. During cold temperature stress, accumulation of the gene encoding the sole Asp-Glu-Ala-Asp (DEAD)-box RNA helicase in Synechocystis sp. PCC 6803, crhR (slr0083), increases 15-fold. Here, we show that crhR is expressed from a dicistronic operon with the methylthiotransferase rimO/miaB (slr0082) gene, followed by rapid processing of the operon transcript into two monocistronic mRNAs. This cleavage event is required for and results in destabilization of the rimO transcript. Results from secondary structure modeling and analysis of RNase E cleavage of the rimO-crhR transcript in vitro suggested that CrhR plays a role in enhancing the rate of the processing in an auto-regulatory manner. Moreover, two putative small RNAs are generated from additional processing, degradation, or both of the rimO transcript. These results suggest a role for the bacterial RNA helicase CrhR in RNase E-dependent mRNA processing in Synechocystis and expand the known range of organisms possessing small RNAs derived from processing of mRNA transcripts.
Collapse
Affiliation(s)
- Albert Remus R Rosana
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Denise S Whitford
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Anzhela Migur
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
| | - Claudia Steglich
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
| | - Sonya L Kujat-Choy
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Wolfgang R Hess
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany.,Freiburg Institute for Advanced Studies, University of Freiburg, Albertstrasse 19, D-79104 Freiburg, Germany
| | - George W Owttrim
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| |
Collapse
|
34
|
Plant Ribonuclease J: An Essential Player in Maintaining Chloroplast RNA Quality Control for Gene Expression. PLANTS 2020; 9:plants9030334. [PMID: 32151111 PMCID: PMC7154860 DOI: 10.3390/plants9030334] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 12/27/2022]
Abstract
RNA quality control is an indispensable but poorly understood process that enables organisms to distinguish functional RNAs from nonfunctional or inhibitory ones. In chloroplasts, whose gene expression activities are required for photosynthesis, retrograde signaling, and plant development, RNA quality control is of paramount importance, as transcription is relatively unregulated. The functional RNA population is distilled from this initial transcriptome by a combination of RNA-binding proteins and ribonucleases. One of the key enzymes is RNase J, a 5′→3′ exoribonuclease and an endoribonuclease that has been shown to trim 5′ RNA termini and eliminate deleterious antisense RNA. In the absence of RNase J, embryo development cannot be completed. Land plant RNase J contains a highly conserved C-terminal domain that is found in GT-1 DNA-binding transcription factors and is not present in its bacterial, archaeal, and algal counterparts. The GT-1 domain may confer specificity through DNA and/or RNA binding and/or protein–protein interactions and thus be an element in the mechanisms that identify target transcripts among diverse RNA populations. Further understanding of chloroplast RNA quality control relies on discovering how RNase J is regulated and how its specificity is imparted.
Collapse
|
35
|
Šiková M, Wiedermannová J, Převorovský M, Barvík I, Sudzinová P, Kofroňová O, Benada O, Šanderová H, Condon C, Krásný L. The torpedo effect in Bacillus subtilis: RNase J1 resolves stalled transcription complexes. EMBO J 2020; 39:e102500. [PMID: 31840842 PMCID: PMC6996504 DOI: 10.15252/embj.2019102500] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 11/26/2019] [Accepted: 11/27/2019] [Indexed: 12/17/2022] Open
Abstract
RNase J1 is the major 5'-to-3' bacterial exoribonuclease. We demonstrate that in its absence, RNA polymerases (RNAPs) are redistributed on DNA, with increased RNAP occupancy on some genes without a parallel increase in transcriptional output. This suggests that some of these RNAPs represent stalled, non-transcribing complexes. We show that RNase J1 is able to resolve these stalled RNAP complexes by a "torpedo" mechanism, whereby RNase J1 degrades the nascent RNA and causes the transcription complex to disassemble upon collision with RNAP. A heterologous enzyme, yeast Xrn1 (5'-to-3' exonuclease), is less efficient than RNase J1 in resolving stalled Bacillus subtilis RNAP, suggesting that the effect is RNase-specific. Our results thus reveal a novel general principle, whereby an RNase can participate in genome-wide surveillance of stalled RNAP complexes, preventing potentially deleterious transcription-replication collisions.
Collapse
Affiliation(s)
- Michaela Šiková
- Institute of Microbiology of the Czech Academy of SciencesPrague 4Czech Republic
| | - Jana Wiedermannová
- Institute of Microbiology of the Czech Academy of SciencesPrague 4Czech Republic
| | - Martin Převorovský
- Department of Cell BiologyFaculty of ScienceCharles UniversityPragueCzech Republic
| | - Ivan Barvík
- Division of Biomolecular PhysicsInstitute of PhysicsCharles UniversityPrague 2Czech Republic
| | - Petra Sudzinová
- Institute of Microbiology of the Czech Academy of SciencesPrague 4Czech Republic
| | - Olga Kofroňová
- Institute of Microbiology of the Czech Academy of SciencesPrague 4Czech Republic
| | - Oldřich Benada
- Institute of Microbiology of the Czech Academy of SciencesPrague 4Czech Republic
| | - Hana Šanderová
- Institute of Microbiology of the Czech Academy of SciencesPrague 4Czech Republic
| | - Ciarán Condon
- UMR8261CNRSUniversité de ParisInstitut de Biologie Physico‐ChimiqueParisFrance
| | - Libor Krásný
- Institute of Microbiology of the Czech Academy of SciencesPrague 4Czech Republic
| |
Collapse
|
36
|
Mu R, Shinde P, Zou Z, Kreth J, Merritt J. Examining the Protein Interactome and Subcellular Localization of RNase J2 Complexes in Streptococcus mutans. Front Microbiol 2019; 10:2150. [PMID: 31620106 PMCID: PMC6759994 DOI: 10.3389/fmicb.2019.02150] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 09/02/2019] [Indexed: 12/18/2022] Open
Abstract
Regulated RNA turnover is vital for the control of gene expression in all cellular life. In Escherichia coli, this process is largely controlled by a stable degradosome complex containing RNase E and a variety of additional enzymes. In the Firmicutes phylum, species lack RNase E and often encode the paralogous enzymes RNase J1 and RNase J2. Unlike RNase J1, surprisingly little is known about the regulatory function and protein interactions of RNase J2, despite being a central pleiotropic regulator for the streptococci and other closely related organisms. Using crosslink coimmunoprecipitation in Streptococcus mutans, we have identified the major proteins found within RNase J2 protein complexes located in the cytoplasm and at the cell membrane. In both subcellular fractions, RNase J2 exhibited the most robust interactions with RNase J1, while additional transient and/or weaker "degradosome-like" interactions were also detected. In addition, RNase J2 exhibits multiple novel interactions that have not been previously reported for any RNase J proteins, some of which were highly biased for either the cytoplasmic or membrane fractions. We also determined that the RNase J2 C-terminal domain (CTD) encodes a structure that is likely conserved among RNase J enzymes and may have an analogous function to the C-terminal portion of RNase E. While we did observe a number of parallels between the RNase J2 interactome and the E. coli degradosome paradigm, our results suggest that S. mutans degradosomes are either unlikely to exist or are quite distinct from those of E. coli.
Collapse
Affiliation(s)
- Rong Mu
- Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University, Portland, OR, United States
| | - Pushkar Shinde
- Emory College of Arts and Sciences, Atlanta, GA, United States
| | - Zhengzhong Zou
- Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University, Portland, OR, United States
| | - Jens Kreth
- Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University, Portland, OR, United States.,Department of Molecular Microbiology and Immunology, School of Medicine, Oregon Health and Science University, Portland, OR, United States
| | - Justin Merritt
- Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University, Portland, OR, United States.,Department of Molecular Microbiology and Immunology, School of Medicine, Oregon Health and Science University, Portland, OR, United States
| |
Collapse
|
37
|
Bechhofer DH, Deutscher MP. Bacterial ribonucleases and their roles in RNA metabolism. Crit Rev Biochem Mol Biol 2019; 54:242-300. [PMID: 31464530 PMCID: PMC6776250 DOI: 10.1080/10409238.2019.1651816] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/22/2019] [Accepted: 07/31/2019] [Indexed: 12/16/2022]
Abstract
Ribonucleases (RNases) are mediators in most reactions of RNA metabolism. In recent years, there has been a surge of new information about RNases and the roles they play in cell physiology. In this review, a detailed description of bacterial RNases is presented, focusing primarily on those from Escherichia coli and Bacillus subtilis, the model Gram-negative and Gram-positive organisms, from which most of our current knowledge has been derived. Information from other organisms is also included, where relevant. In an extensive catalog of the known bacterial RNases, their structure, mechanism of action, physiological roles, genetics, and possible regulation are described. The RNase complement of E. coli and B. subtilis is compared, emphasizing the similarities, but especially the differences, between the two. Included are figures showing the three major RNA metabolic pathways in E. coli and B. subtilis and highlighting specific steps in each of the pathways catalyzed by the different RNases. This compilation of the currently available knowledge about bacterial RNases will be a useful tool for workers in the RNA field and for others interested in learning about this area.
Collapse
Affiliation(s)
- David H. Bechhofer
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Murray P. Deutscher
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, USA
| |
Collapse
|
38
|
Vasilyev N, Gao A, Serganov A. Noncanonical features and modifications on the 5'-end of bacterial sRNAs and mRNAs. WILEY INTERDISCIPLINARY REVIEWS. RNA 2019; 10:e1509. [PMID: 30276982 PMCID: PMC6657780 DOI: 10.1002/wrna.1509] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/05/2018] [Accepted: 09/17/2018] [Indexed: 12/20/2022]
Abstract
Although many eukaryotic transcripts contain cap structures, it has been long thought that bacterial RNAs do not carry any special modifications on their 5'-ends. In bacteria, primary transcripts are produced by transcription initiated with a nucleoside triphosphate and are therefore triphosphorylated on 5'-ends. Some transcripts are then processed by nucleases that yield monophosphorylated RNAs for specific cellular activities. Many primary transcripts are also converted to monophosphorylated species by removal of the terminal pyrophosphate for 5'-end-dependent degradation. Recent studies surprisingly revealed an expanded repertoire of chemical groups on 5'-ends of bacterial RNAs. In addition to mono- and triphosphorylated moieties, some mRNAs and sRNAs contain cap-like structures and diphosphates on their 5'-ends. Although incorporation and removal of these groups have become better understood in recent years, the physiological significance of these modifications remain obscure. This review highlights recent studies aimed at identification and elucidation of novel modifications on the 5'-ends of bacterial RNAs and discusses possible physiological applications of the modified RNAs. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNA Structure and Dynamics > RNA Structure, Dynamics, and Chemistry RNA Processing > Capping and 5' End Modifications.
Collapse
Affiliation(s)
- Nikita Vasilyev
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Ang Gao
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Alexander Serganov
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| |
Collapse
|
39
|
Halpert M, Liveanu V, Glaser F, Schuster G. The Arabidopsis chloroplast RNase J displays both exo- and robust endonucleolytic activities. PLANT MOLECULAR BIOLOGY 2019; 99:17-29. [PMID: 30511330 DOI: 10.1007/s11103-018-0799-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 11/22/2018] [Indexed: 05/17/2023]
Abstract
Arabidopsis chloroplast RNase J displaces both exo- and endo-ribonucleolytic activities and contains a unique GT-1 DNA binding domain. Control of chloroplast gene expression is predominantly at the post-transcriptional level via the coordinated action of nuclear encoded ribonucleases and RNA-binding proteins. The 5' end maturation of mRNAs ascribed to the combined action of 5'→3' exoribonuclease and gene-specific RNA-binding proteins of the pentatricopeptide repeat family and others that impede the progression of this nuclease. The exo- and endoribonuclease RNase J, the only prokaryotic 5'→3' ribonuclease that is commonly present in bacteria, Archaea, as well as in the chloroplasts of higher plants and green algae, has been implicated in this process. Interestingly, in addition to the metalo-β-lactamase and β-CASP domains, RNase J of plants contains a conserved GT-1 domain that was previously characterized in transcription factors that function in light and stress responding genes. Here, we show that the Arabidopsis RNase J (AtRNase J), when analyzed in vitro with synthetic RNAs, displays both 5'→3' exonucleolytic activity, as well as robust endonucleolytic activity as compared to its bacterial homolog RNase J1 of Bacillus subtilis. AtRNase J degraded single-stranded RNA and DNA molecules but displays limited activity on double stranded RNA. The addition of three guanosines at the 5' end of the substrate significantly inhibited the degradation activity, indicating that the sequence and structure of the RNA substrate modulate the ribonucleolytic activity. Mutation of three amino acid in the catalytic reaction center significantly inhibited both the endonucleolytic and exonucleolytic degradation activities, while deletion of the carboxyl GT-1 domain that is unique to the plant RNAse J proteins, had a little or no significant effect. The robust endonucleolytic activity of AtRNase J suggests its involvement in the processing and degradation of RNA in the chloroplast.
Collapse
Affiliation(s)
- Michal Halpert
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Varda Liveanu
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Fabian Glaser
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
- Bioinformatics Knowledge Unit, The Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Gadi Schuster
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel.
| |
Collapse
|
40
|
Clouet-d'Orval B, Batista M, Bouvier M, Quentin Y, Fichant G, Marchfelder A, Maier LK. Insights into RNA-processing pathways and associated RNA-degrading enzymes in Archaea. FEMS Microbiol Rev 2018; 42:579-613. [PMID: 29684129 DOI: 10.1093/femsre/fuy016] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 04/17/2018] [Indexed: 12/20/2022] Open
Abstract
RNA-processing pathways are at the centre of regulation of gene expression. All RNA transcripts undergo multiple maturation steps in addition to covalent chemical modifications to become functional in the cell. This includes destroying unnecessary or defective cellular RNAs. In Archaea, information on mechanisms by which RNA species reach their mature forms and associated RNA-modifying enzymes are still fragmentary. To date, most archaeal actors and pathways have been proposed in light of information gathered from Bacteria and Eukarya. In this context, this review provides a state of the art overview of archaeal endoribonucleases and exoribonucleases that cleave and trim RNA species and also of the key small archaeal proteins that bind RNAs. Furthermore, synthetic up-to-date views of processing and biogenesis pathways of archaeal transfer and ribosomal RNAs as well as of maturation of stable small non-coding RNAs such as CRISPR RNAs, small C/D and H/ACA box guide RNAs, and other emerging classes of small RNAs are described. Finally, prospective post-transcriptional mechanisms to control archaeal messenger RNA quality and quantity are discussed.
Collapse
Affiliation(s)
- Béatrice Clouet-d'Orval
- Laboratoire de Microbiologie et de Génétique Moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 31062 Toulouse, France
| | - Manon Batista
- Laboratoire de Microbiologie et de Génétique Moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 31062 Toulouse, France
| | - Marie Bouvier
- Laboratoire de Microbiologie et de Génétique Moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 31062 Toulouse, France
| | - Yves Quentin
- Laboratoire de Microbiologie et de Génétique Moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 31062 Toulouse, France
| | - Gwennaele Fichant
- Laboratoire de Microbiologie et de Génétique Moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 31062 Toulouse, France
| | | | | |
Collapse
|
41
|
Abstract
RNases are key enzymes involved in RNA maturation and degradation. Although they play a crucial role in all domains of life, bacteria, archaea, and eukaryotes have evolved with their own sets of RNases and proteins modulating their activities. In bacteria, these enzymes allow modulation of gene expression to adapt to rapidly changing environments. Today, >20 RNases have been identified in both Escherichia coli and Bacillus subtilis, the paradigms of the Gram-negative and Gram-positive bacteria, respectively. However, only a handful of these enzymes are common to these two organisms and some of them are essential to only one. Moreover, although sets of RNases can be very similar in closely related bacteria such as the Firmicutes Staphylococcus aureus and B. subtilis, the relative importance of individual enzymes in posttranscriptional regulation in these organisms varies. In this review, we detail the role of the main RNases involved in RNA maturation and degradation in Gram-positive bacteria, with an emphasis on the roles of RNase J1, RNase III, and RNase Y. We also discuss how other proteins such as helicases can modulate the RNA-degradation activities of these enzymes.
Collapse
|
42
|
Abstract
The bacterial endoribonuclease RNase E occupies a pivotal position in the control of gene expression, as its actions either commit transcripts to an irreversible fate of rapid destruction or unveil their hidden functions through specific processing. Moreover, the enzyme contributes to quality control of rRNAs. The activity of RNase E can be directed and modulated by signals provided through regulatory RNAs that guide the enzyme to specific transcripts that are to be silenced. Early in its evolutionary history, RNase E acquired a natively unfolded appendage that recruits accessory proteins and RNA. These accessory factors facilitate the activity of RNase E and include helicases that remodel RNA and RNA-protein complexes, and polynucleotide phosphorylase, a relative of the archaeal and eukaryotic exosomes. RNase E also associates with enzymes from central metabolism, such as enolase and aconitase. RNase E-based complexes are diverse in composition, but generally bear mechanistic parallels with eukaryotic machinery involved in RNA-induced gene regulation and transcript quality control. That these similar processes arose independently underscores the universality of RNA-based regulation in life. Here we provide a synopsis and perspective of the contributions made by RNase E to sustain robust gene regulation with speed and accuracy.
Collapse
|
43
|
Jardine JL, Stoychev S, Mavumengwana V, Ubomba-Jaswa E. Screening of potential bioremediation enzymes from hot spring bacteria using conventional plate assays and liquid chromatography - Tandem mass spectrometry (Lc-Ms/Ms). JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 223:787-796. [PMID: 29986326 DOI: 10.1016/j.jenvman.2018.06.089] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Revised: 06/15/2018] [Accepted: 06/28/2018] [Indexed: 06/08/2023]
Abstract
The search for an eco-friendly, non-toxic, economical and efficient means of cleaning water through bioremediation is not only more favourable but critical to maintaining water quality globally especially in water-scarce countries. Thermophilic bacteria including Bacillus species are an important source of novel enzymes for biotechnology applications. In this study, 56 bacterial isolates which were cultured from five hot springs in South Africa were identified predominantly as Bacillus sp. or Bacillus-related spp by 16S rDNA gene sequencing. These isolates were screened for potentially useful enzymes for water bioremediation. Using conventional agar plate assays, 56% (n = 43), 68% (n = 38) and 16% (n = 31) were positive for amylase, protease and bromothymol blue decolorisation respectively. In liquid starch culture, three amylase-positive isolates differentially degraded starch by 34% (isolate 20S) to 98% (isolate 9T). Phenol degradation revealed that five out of thirty reduced phenol up to 42% by colorimetric assay. A thermophilic strain of Anoxybacillus rupiensis 19S (optimal growth temperature of 50 °C), which degraded starch, protein and phenol, was selected for further analysis by tandem LC-MS/MS. This newer technique identified potential enzymes for water bioremediation relating to pollutants from the food industry (amylase, proteases), polyaromatic hydrocarbons and dye pollutants (catalase peroxidase, superoxide dismutase, azoreductase, quinone oxidoreductase), antibiotic residues (ribonucleases), solubilisation of phosphates (inorganic pyrophosphatase) and reduction of chromate and lead. In addition, potential enzymes for biomonitoring of environmental pollutants were also identified. Specifically, dehydrogenases were found to decrease as the level of inorganic heavy metals and petroleum increased in soil samples. This study concludes that bacteria found in South African hot springs are a potential source of novel enzymes with tandem LC-MS/MS revealing substantially more information compared with conventional assays, which can be used for various applications of water bioremediation.
Collapse
Affiliation(s)
- J L Jardine
- Department of Biotechnology, University of Johannesburg, 37 Nind Street, Doornfontein, Gauteng, South Africa
| | - S Stoychev
- Council for Scientific and Industrial Research, Biosciences, Box 395, Pretoria 0001, South Africa
| | - V Mavumengwana
- Department of Biotechnology, University of Johannesburg, 37 Nind Street, Doornfontein, Gauteng, South Africa
| | - E Ubomba-Jaswa
- Department of Biotechnology, University of Johannesburg, 37 Nind Street, Doornfontein, Gauteng, South Africa; Water Research Commission, Lynnwood Bridge Office Park, Bloukrans Building, 4 Daventry Street, Lynnwood Manor, Pretoria, South Africa.
| |
Collapse
|
44
|
Mora L, Ngo S, Laalami S, Putzer H. In Vitro Study of the Major Bacillus subtilis Ribonucleases Y and J. Methods Enzymol 2018; 612:343-359. [PMID: 30502948 DOI: 10.1016/bs.mie.2018.08.004] [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] [Indexed: 12/24/2022]
Abstract
The metabolic instability of mRNA is fundamental to the adaptation of gene expression. In bacteria, mRNA decay follows first-order kinetics and is primarily controlled at the steps initiating degradation. In the model Gram-positive organism Bacillus subtilis, the major mRNA decay pathway initiates with an endonucleolytic cleavage by the membrane-associated RNase Y. High-throughput sequencing has identified a large number of potential mRNA substrates but our understanding of what parameters affect cleavage in vivo is still quite limited. In vitro reconstitution of the cleavage event is thus instrumental in defining the mechanistic details, substrate recognition, the role of auxiliary factors, and of membrane localization in cleavage. In this chapter, we describe not only the purification and assay of RNase Y but also RNase J1/J2 which shares a similar low-specificity endoribonucleolytic activity with RNase Y. We highlight potential problems in the set-up of these assays and include methods that allow purification of full-length RNase Y and its incorporation in multilamellar vesicles created from native B. subtilis lipids that might best mimic in vivo conditions.
Collapse
Affiliation(s)
- Liliana Mora
- CNRS UMR8261-Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
| | - Saravuth Ngo
- CNRS UMR8261-Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
| | - Soumaya Laalami
- CNRS UMR8261-Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
| | - Harald Putzer
- CNRS UMR8261-Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, Paris, France.
| |
Collapse
|
45
|
Förstner KU, Reuscher CM, Haberzettl K, Weber L, Klug G. RNase E cleavage shapes the transcriptome ofRhodobacter sphaeroidesand strongly impacts phototrophic growth. Life Sci Alliance 2018; 1:e201800080. [PMID: 30456366 PMCID: PMC6238624 DOI: 10.26508/lsa.201800080] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/13/2018] [Accepted: 07/13/2018] [Indexed: 11/24/2022] Open
Abstract
This study identifies the cleavage sites of the endoribonuclease RNase E in the Rhodobacter sphaeroides transcriptome and demonstrates its effect on oxidative stress resistance and phototrophic growth. Bacteria adapt to changing environmental conditions by rapid changes in their transcriptome. This is achieved not only by adjusting rates of transcription but also by processing and degradation of RNAs. We applied TIER-Seq (transiently inactivating an endoribonuclease followed by RNA-Seq) for the transcriptome-wide identification of RNase E cleavage sites and of 5′ RNA ends, which are enriched when RNase E activity is reduced in Rhodobacter sphaeroides. These results reveal the importance of RNase E for the maturation and turnover of mRNAs, rRNAs, and sRNAs in this guanine-cytosine-rich α-proteobacterium, some of the latter have well-described functions in the oxidative stress response. In agreement with this, a role of RNase E in the oxidative stress response is demonstrated. A remarkably strong phenotype of a mutant with reduced RNase E activity was observed regarding the formation of photosynthetic complexes and phototrophic growth, whereas there was no effect on chemotrophic growth.
Collapse
Affiliation(s)
- Konrad U Förstner
- German National Library of Medicine—Information Center for Life Sciences, Cologne, Germany
- Technical University of Cologne, Faculty for Information and Communication Sciences, Cologne, Germany
- Core Unit Systems Medicine, Institutes of Molecular Infection Biology, University of Würzburg, Würzburg, Germany
- Correspondence:
| | - Carina M Reuscher
- Institut für Mikrobiologie und Molekularbiologie, Interdisciplinary Research Center for Biosystems, Universität Giessen, Giessen, Germany
| | - Kerstin Haberzettl
- Institut für Mikrobiologie und Molekularbiologie, Interdisciplinary Research Center for Biosystems, Universität Giessen, Giessen, Germany
| | - Lennart Weber
- Institut für Mikrobiologie und Molekularbiologie, Interdisciplinary Research Center for Biosystems, Universität Giessen, Giessen, Germany
| | - Gabriele Klug
- Institut für Mikrobiologie und Molekularbiologie, Interdisciplinary Research Center for Biosystems, Universität Giessen, Giessen, Germany
| |
Collapse
|
46
|
Schwenk S, Arnvig KB. Regulatory RNA in Mycobacterium tuberculosis, back to basics. Pathog Dis 2018; 76:4966984. [PMID: 29796669 PMCID: PMC7615687 DOI: 10.1093/femspd/fty035] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/09/2018] [Indexed: 01/17/2023] Open
Abstract
Since the turn of the millenium, RNA-based control of gene expression has added an extra dimension to the central dogma of molecular biology. Still, the roles of Mycobacterium tuberculosis regulatory RNAs and the proteins that facilitate their functions remain elusive, although there can be no doubt that RNA biology plays a central role in the baterium's adaptation to its many host environments. In this review, we have presented examples from model organisms and from M. tuberculosis to showcase the abundance and versatility of regulatory RNA, in order to emphasise the importance of these 'fine-tuners' of gene expression.
Collapse
MESH Headings
- Aconitate Hydratase/genetics
- Aconitate Hydratase/metabolism
- Bacterial Proteins/genetics
- Bacterial Proteins/metabolism
- Gene Expression Regulation, Bacterial
- Host-Pathogen Interactions
- Humans
- Mycobacterium tuberculosis/genetics
- Mycobacterium tuberculosis/metabolism
- Mycobacterium tuberculosis/pathogenicity
- Nucleic Acid Conformation
- RNA Stability
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- RNA, Small Cytoplasmic/genetics
- RNA, Small Cytoplasmic/metabolism
- RNA, Small Nuclear/genetics
- RNA, Small Nuclear/metabolism
- RNA, Small Untranslated/genetics
- RNA, Small Untranslated/metabolism
- Regulatory Sequences, Ribonucleic Acid
- Riboswitch
- Tuberculosis/microbiology
Collapse
Affiliation(s)
- Stefan Schwenk
- Institute for Structural and Molecular Biology, University College London, London WC1E 6BT, UK
| | - Kristine B Arnvig
- Institute for Structural and Molecular Biology, University College London, London WC1E 6BT, UK
| |
Collapse
|
47
|
Liponska A, Jamalli A, Kuras R, Suay L, Garbe E, Wollman FA, Laalami S, Putzer H. Tracking the elusive 5' exonuclease activity of Chlamydomonas reinhardtii RNase J. PLANT MOLECULAR BIOLOGY 2018; 96:641-653. [PMID: 29600502 DOI: 10.1007/s11103-018-0720-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 03/14/2018] [Indexed: 06/08/2023]
Abstract
Chlamydomonas RNase J is the first member of this enzyme family that has endo- but no intrinsic 5' exoribonucleolytic activity. This questions its proposed role in chloroplast mRNA maturation. RNA maturation and stability in the chloroplast are controlled by nuclear-encoded ribonucleases and RNA binding proteins. Notably, mRNA 5' end maturation is thought to be achieved by the combined action of a 5' exoribonuclease and specific pentatricopeptide repeat proteins (PPR) that block the progression of the nuclease. In Arabidopsis the 5' exo- and endoribonuclease RNase J has been implicated in this process. Here, we verified the chloroplast localization of the orthologous Chlamydomonas (Cr) RNase J and studied its activity, both in vitro and in vivo in a heterologous B. subtilis system. Our data show that Cr RNase J has endo- but no significant intrinsic 5' exonuclease activity that would be compatible with its proposed role in mRNA maturation. This is the first example of an RNase J ortholog that does not possess a 5' exonuclease activity. A yeast two-hybrid screen revealed a number of potential interaction partners but three of the most promising candidates tested, failed to induce the latent exonuclease activity of Cr RNase J. We still favor the hypothesis that Cr RNase J plays an important role in RNA metabolism, but our findings suggest that it rather acts as an endoribonuclease in the chloroplast.
Collapse
Affiliation(s)
- Anna Liponska
- CNRS UMR8261 - Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Ailar Jamalli
- CNRS UMR8261 - Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
- Laboratory Science Research Center, Golestan University of Medical Sciences, Gorgan, Iran
| | - Richard Kuras
- CNRS UMR7141 (Associated with Université Pierre et Marie Curie), Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Loreto Suay
- CNRS UMR7141 (Associated with Université Pierre et Marie Curie), Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Enrico Garbe
- CNRS UMR8261 - Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Francis-André Wollman
- CNRS UMR7141 (Associated with Université Pierre et Marie Curie), Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Soumaya Laalami
- CNRS UMR8261 - Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Harald Putzer
- CNRS UMR8261 - Université Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France.
| |
Collapse
|
48
|
The Sole DEAD-Box RNA Helicase of the Gastric Pathogen Helicobacter pylori Is Essential for Colonization. mBio 2018; 9:mBio.02071-17. [PMID: 29588407 PMCID: PMC5874925 DOI: 10.1128/mbio.02071-17] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Present in every kingdom of life, generally in multiple copies, DEAD-box RNA helicases are specialized enzymes that unwind RNA secondary structures. They play major roles in mRNA decay, ribosome biogenesis, and adaptation to cold temperatures. Most bacteria have multiple DEAD-box helicases that present both specialized and partially redundant functions. By using phylogenomics, we revealed that the Helicobacter genus, including the major gastric pathogen H. pylori, is among the exceptions, as it encodes a sole DEAD-box RNA helicase. In H. pylori, this helicase, designated RhpA, forms a minimal RNA degradosome together with the essential RNase, RNase J, a major player in the control of RNA decay. Here, we used H. pylori as a model organism with a sole DEAD-box helicase and investigated the role of this helicase in H. pylori physiology, ribosome assembly, and during in vivo colonization. Our data showed that RhpA is dispensable for growth at 37°C but crucial at 33°C, suggesting an essential role of the helicase in cold adaptation. Moreover, we found that a ΔrhpA mutant was impaired in motility and deficient in colonization of the mouse model. RhpA is involved in the maturation of 16S rRNA at 37°C and is associated with translating ribosomes. At 33°C, RhpA is, in addition, recruited to individual ribosomal subunits. Finally, via its role in the RNA degradosome, RhpA directs the regulation of the expression of its partner, RNase J. RhpA is thus a multifunctional enzyme that, in H. pylori, plays a central role in gene regulation and in the control of virulence.IMPORTANCE We present the results of our study on the role of RhpA, the sole DEAD-box RNA helicase encoded by the major gastric pathogen Helicobacter pylori We observed that all the Helicobacter species possess such a sole helicase, in contrast to most free-living bacteria. RhpA is not essential for growth of H. pylori under normal conditions. However, deletion of rhpA leads to a motility defect and to total inhibition of the ability of H. pylori to colonize a mouse model. We also demonstrated that this helicase encompasses most of the functions of its specialized orthologs described so far. We found that RhpA is a key element of the bacterial adaptation to colder temperatures and plays a minor role in ribosome biogenesis. Finally, RhpA regulates transcription of the rnj gene encoding RNase J, its essential partner in the minimal H. pylori RNA degradosome, and thus plays a crucial role in the control of RNA decay.
Collapse
|
49
|
Abstract
RNA molecules have the tendency to fold into complex structures or to associate with complementary RNAs that exoribonucleases have difficulties processing or degrading. Therefore, degradosomes in bacteria and organelles as well as exosomes in eukaryotes have teamed-up with RNA helicases. Whereas bacterial degradosomes are associated with RNA helicases from the DEAD-box family, the exosomes and mitochondrial degradosome use the help of Ski2-like and Suv3 RNA helicases.
Collapse
|
50
|
Redder P. Molecular and genetic interactions of the RNA degradation machineries in Firmicute bacteria. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9. [PMID: 29314657 DOI: 10.1002/wrna.1460] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 09/10/2017] [Accepted: 11/10/2017] [Indexed: 12/12/2022]
Abstract
Correct balance between bacterial RNA degradation and synthesis is essential for controlling expression level of all RNAs. The RNA polymerase, which performs the RNA synthesis, is highly conserved across the bacterial domain. However, this is surprisingly not the case for the RNA degradation machinery, which is composed of different subunits and performs different enzymatic reactions, depending on the organism. In Escherichia coli, the RNA decay is performed by the degradosome complex, which forms around the membrane-associated endoribonuclease RNase E, and is stable enough to be purified without falling apart. In contrast, many Firmicutes, for example, Bacillus subtilis, Staphylococcus aureus, and Streptococcus pneumoniae, do not encode an RNase E homolog, but instead have the endoribonuclease RNase Y and the exo- and endo-ribonuclease RNase J complex. A wide range of experiments have been performed, mainly with B. subtilis and S. aureus, to determine which interactions exist between the various RNA decay enzymes in the Firmicutes, with the goal of understanding how RNA degradation (and thus gene expression homeostasis and regulation) is organized in these organisms. The in vivo and in vitro data is diverse, and does not always concur. This overview gathers the data on interactions between Firmicute RNA degradation factors, to highlight the similarities and differences between experimental data from different experiments and from different organisms. WIREs RNA 2018, 9:e1460. doi: 10.1002/wrna.1460 This article is categorized under: RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Turnover and Surveillance > Regulation of RNA Stability.
Collapse
Affiliation(s)
- Peter Redder
- Laboratoire de Microbiologie et Génétique Moléculaires, UMR5100, Centre de Biologie Integrative, Paul Sabatier University, Toulouse, France
| |
Collapse
|