1
|
How to Shut Down Transcription in Archaea during Virus Infection. Microorganisms 2022; 10:microorganisms10091824. [PMID: 36144426 PMCID: PMC9501531 DOI: 10.3390/microorganisms10091824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/09/2022] [Accepted: 09/10/2022] [Indexed: 11/16/2022] Open
Abstract
Multisubunit RNA polymerases (RNAPs) carry out transcription in all domains of life; during virus infection, RNAPs are targeted by transcription factors encoded by either the cell or the virus, resulting in the global repression of transcription with distinct outcomes for different host–virus combinations. These repressors serve as versatile molecular probes to study RNAP mechanisms, as well as aid the exploration of druggable sites for the development of new antibiotics. Here, we review the mechanisms and structural basis of RNAP inhibition by the viral repressor RIP and the crenarchaeal negative regulator TFS4, which follow distinct strategies. RIP operates by occluding the DNA-binding channel and mimicking the initiation factor TFB/TFIIB. RIP binds tightly to the clamp and locks it into one fixed position, thereby preventing conformational oscillations that are critical for RNAP function as it progresses through the transcription cycle. TFS4 engages with RNAP in a similar manner to transcript cleavage factors such as TFS/TFIIS through the NTP-entry channel; TFS4 interferes with the trigger loop and bridge helix within the active site by occlusion and allosteric mechanisms, respectively. The conformational changes in RNAP described above are universally conserved and are also seen in inactive dimers of eukaryotic RNAPI and several inhibited RNAP complexes of both bacterial and eukaryotic RNA polymerases, including inactive states that precede transcription termination. A comparison of target sites and inhibitory mechanisms reveals that proteinaceous repressors and RNAP-specific antibiotics use surprisingly common ways to inhibit RNAP function.
Collapse
|
2
|
Phung DK, Etienne C, Batista M, Langendijk-Genevaux P, Moalic Y, Laurent S, Liuu S, Morales V, Jebbar M, Fichant G, Bouvier M, Flament D, Clouet-d’Orval B. RNA processing machineries in Archaea: the 5'-3' exoribonuclease aRNase J of the β-CASP family is engaged specifically with the helicase ASH-Ski2 and the 3'-5' exoribonucleolytic RNA exosome machinery. Nucleic Acids Res 2020; 48:3832-3847. [PMID: 32030412 PMCID: PMC7144898 DOI: 10.1093/nar/gkaa052] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/14/2020] [Accepted: 01/23/2020] [Indexed: 01/22/2023] Open
Abstract
A network of RNA helicases, endoribonucleases and exoribonucleases regulates the quantity and quality of cellular RNAs. To date, mechanistic studies focussed on bacterial and eukaryal systems due to the challenge of identifying the main drivers of RNA decay and processing in Archaea. Here, our data support that aRNase J, a 5'-3' exoribonuclease of the β-CASP family conserved in Euryarchaeota, engages specifically with a Ski2-like helicase and the RNA exosome to potentially exert control over RNA surveillance, at the vicinity of the ribosome. Proteomic landscapes and direct protein-protein interaction analyses, strengthened by comprehensive phylogenomic studies demonstrated that aRNase J interplay with ASH-Ski2 and a cap exosome subunit. Finally, Thermococcus barophilus whole-cell extract fractionation experiments provide evidences that an aRNase J/ASH-Ski2 complex might exist in vivo and hint at an association of aRNase J with the ribosome that is emphasised in absence of ASH-Ski2. Whilst aRNase J homologues are found among bacteria, the RNA exosome and the Ski2-like RNA helicase have eukaryotic homologues, underlining the mosaic aspect of archaeal RNA machines. Altogether, these results suggest a fundamental role of β-CASP RNase/helicase complex in archaeal RNA metabolism.
Collapse
Affiliation(s)
- Duy Khanh Phung
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
| | - Clarisse Etienne
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
| | - Manon Batista
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
| | - Petra Langendijk-Genevaux
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
| | - Yann Moalic
- Ifremer, Univ Brest, CNRS, Laboratoire de Microbiologie des Environnements Extrêmes, F-29280 Plouzané, France
| | - Sébastien Laurent
- Ifremer, Univ Brest, CNRS, Laboratoire de Microbiologie des Environnements Extrêmes, F-29280 Plouzané, France
| | - Sophie Liuu
- Micalis Institute, PAPPSO, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Violette Morales
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
| | - Mohamed Jebbar
- Ifremer, Univ Brest, CNRS, Laboratoire de Microbiologie des Environnements Extrêmes, F-29280 Plouzané, France
| | - Gwennaele Fichant
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
| | - Marie Bouvier
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
| | - Didier Flament
- Ifremer, Univ Brest, CNRS, Laboratoire de Microbiologie des Environnements Extrêmes, F-29280 Plouzané, France
| | - Béatrice Clouet-d’Orval
- Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Paul Sabatier, F-31062 Toulouse, France
- To whom correspondence should be addressed. Tel: +33 561 335 875; Fax: +33 561 335 886;
| |
Collapse
|
3
|
Blombach F, Matelska D, Fouqueau T, Cackett G, Werner F. Key Concepts and Challenges in Archaeal Transcription. J Mol Biol 2019; 431:4184-4201. [PMID: 31260691 DOI: 10.1016/j.jmb.2019.06.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/18/2019] [Accepted: 06/20/2019] [Indexed: 12/17/2022]
Abstract
Transcription is enabled by RNA polymerase and general factors that allow its progress through the transcription cycle by facilitating initiation, elongation and termination. The transitions between specific stages of the transcription cycle provide opportunities for the global and gene-specific regulation of gene expression. The exact mechanisms and the extent to which the different steps of transcription are exploited for regulation vary between the domains of life, individual species and transcription units. However, a surprising degree of conservation is apparent. Similar key steps in the transcription cycle can be targeted by homologous or unrelated factors providing insights into the mechanisms of RNAP and the evolution of the transcription machinery. Archaea are bona fide prokaryotes but employ a eukaryote-like transcription system to express the information of bacteria-like genomes. Thus, archaea provide the means not only to study transcription mechanisms of interesting model systems but also to test key concepts of regulation in this arena. In this review, we discuss key principles of archaeal transcription, new questions that still await experimental investigation, and how novel integrative approaches hold great promise to fill this gap in our knowledge.
Collapse
Affiliation(s)
- Fabian Blombach
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom.
| | - Dorota Matelska
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Thomas Fouqueau
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Gwenny Cackett
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom
| | - Finn Werner
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, United Kingdom.
| |
Collapse
|