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Asadiatouei P, Salem CB, Wanninger S, Ploetz E, Lamb DC. Deep-LASI, single-molecule data analysis software. Biophys J 2024:S0006-3495(24)00133-4. [PMID: 38384132 DOI: 10.1016/j.bpj.2024.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/15/2024] [Accepted: 02/19/2024] [Indexed: 02/23/2024] Open
Abstract
By avoiding ensemble averaging, single-molecule methods provide novel means of extracting mechanistic insights into function of material and molecules at the nanoscale. However, one of the big limitations is the vast amount of data required for analyzing and extracting the desired information, which is time-consuming and user dependent. Here, we introduce Deep-LASI, a software suite for the manual and automatic analysis of single-molecule traces, interactions, and the underlying kinetics. The software can handle data from one-, two- and three-color fluorescence data, and was particularly designed for the analysis of two- and three-color single-molecule fluorescence resonance energy transfer experiments. The functionalities of the software include: the registration of multiple-channels, trace sorting and categorization, determination of the photobleaching steps, calculation of fluorescence resonance energy transfer correction factors, and kinetic analyses based on hidden Markov modeling or deep neural networks. After a kinetic analysis, the ensuing transition density plots are generated, which can be used for further quantification of the kinetic parameters of the system. Each step in the workflow can be performed manually or with the support of machine learning algorithms. Upon reading in the initial data set, it is also possible to perform the remaining analysis steps automatically without additional supervision. Hence, the time dedicated to the analysis of single-molecule experiments can be reduced from days/weeks to minutes. After a thorough description of the functionalities of the software, we also demonstrate the capabilities of the software via the analysis of a previously published dynamic three-color DNA origami structure fluctuating between three states. With the drastic time reduction in data analysis, new types of experiments become realistically possible that complement our currently available palette of methodologies for investigating the nanoworld.
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Affiliation(s)
- Pooyeh Asadiatouei
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Munich, Germany
| | - Clemens-Bässem Salem
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Munich, Germany
| | - Simon Wanninger
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Munich, Germany
| | - Evelyn Ploetz
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Munich, Germany.
| | - Don C Lamb
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Munich, Germany.
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2
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Brouwer I, Kerklingh E, van Leeuwen F, Lenstra TL. Dynamic epistasis analysis reveals how chromatin remodeling regulates transcriptional bursting. Nat Struct Mol Biol 2023; 30:692-702. [PMID: 37127821 DOI: 10.1038/s41594-023-00981-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 03/30/2023] [Indexed: 05/03/2023]
Abstract
Transcriptional bursting has been linked to the stochastic positioning of nucleosomes. However, how bursting is regulated by the remodeling of promoter nucleosomes is unknown. Here, we use single-molecule live-cell imaging of GAL10 transcription in Saccharomyces cerevisiae to measure how bursting changes upon combined perturbations of chromatin remodelers, the transcription factor Gal4 and preinitiation complex components. Using dynamic epistasis analysis, we reveal how the remodeling of different nucleosomes regulates transcriptional bursting parameters. At the nucleosome covering the Gal4 binding sites, RSC and Gal4 binding synergistically facilitate each burst. Conversely, nucleosome remodeling at the TATA box controls only the first burst upon galactose induction. At canonical TATA boxes, the nucleosomes are displaced by TBP binding to allow for transcription activation even in the absence of remodelers. Overall, our results reveal how promoter nucleosome remodeling together with Gal4 and preinitiation complex binding regulates transcriptional bursting.
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Affiliation(s)
- Ineke Brouwer
- Division of Gene Regulation, the Netherlands Cancer Institute, Oncode Institute, Amsterdam, the Netherlands
| | - Emma Kerklingh
- Division of Gene Regulation, the Netherlands Cancer Institute, Oncode Institute, Amsterdam, the Netherlands
| | - Fred van Leeuwen
- Division of Gene Regulation, the Netherlands Cancer Institute, Amsterdam, the Netherlands
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Tineke L Lenstra
- Division of Gene Regulation, the Netherlands Cancer Institute, Oncode Institute, Amsterdam, the Netherlands.
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3
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Woike S, Eustermann S, Jung J, Wenzl SJ, Hagemann G, Bartho J, Lammens K, Butryn A, Herzog F, Hopfner KP. Structural basis for TBP displacement from TATA box DNA by the Swi2/Snf2 ATPase Mot1. Nat Struct Mol Biol 2023; 30:640-649. [PMID: 37106137 PMCID: PMC7615866 DOI: 10.1038/s41594-023-00966-0] [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: 03/22/2022] [Accepted: 03/13/2023] [Indexed: 04/29/2023]
Abstract
The Swi2/Snf2 family transcription regulator Modifier of Transcription 1 (Mot1) uses adenosine triphosphate (ATP) to dissociate and reallocate the TATA box-binding protein (TBP) from and between promoters. To reveal how Mot1 removes TBP from TATA box DNA, we determined cryogenic electron microscopy structures that capture different states of the remodeling reaction. The resulting molecular video reveals how Mot1 dissociates TBP in a process that, intriguingly, does not require DNA groove tracking. Instead, the motor grips DNA in the presence of ATP and swings back after ATP hydrolysis, moving TBP to a thermodynamically less stable position on DNA. Dislodged TBP is trapped by a chaperone element that blocks TBP's DNA binding site. Our results show how Swi2/Snf2 proteins can remodel protein-DNA complexes through DNA bending without processive DNA tracking and reveal mechanistic similarities to RNA gripping DEAD box helicases and RIG-I-like immune sensors.
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Affiliation(s)
- Stephan Woike
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
| | - Sebastian Eustermann
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Heidelberg, Germany
| | - James Jung
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Simon Josef Wenzl
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
| | - Götz Hagemann
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
| | - Joseph Bartho
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
| | - Katja Lammens
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
| | - Agata Butryn
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK
| | - Franz Herzog
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany
- Institute Krems Bioanalytics, IMC University of Applied Sciences, Krems, Austria
| | - Karl-Peter Hopfner
- Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany.
- Gene Center, Ludwig-Maximilians-Universität, Munich, Germany.
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4
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Savinkova LK, Sharypova EB, Kolchanov NA. On the Role of TATA Boxes and TATA-Binding Protein in Arabidopsis thaliana. PLANTS (BASEL, SWITZERLAND) 2023; 12:1000. [PMID: 36903861 PMCID: PMC10005294 DOI: 10.3390/plants12051000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/13/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
For transcription initiation by RNA polymerase II (Pol II), all eukaryotes require assembly of basal transcription machinery on the core promoter, a region located approximately in the locus spanning a transcription start site (-50; +50 bp). Although Pol II is a complex multi-subunit enzyme conserved among all eukaryotes, it cannot initiate transcription without the participation of many other proteins. Transcription initiation on TATA-containing promoters requires the assembly of the preinitiation complex; this process is triggered by an interaction of TATA-binding protein (TBP, a component of the general transcription factor TFIID (transcription factor II D)) with a TATA box. The interaction of TBP with various TATA boxes in plants, in particular Arabidopsis thaliana, has hardly been investigated, except for a few early studies that addressed the role of a TATA box and substitutions in it in plant transcription systems. This is despite the fact that the interaction of TBP with TATA boxes and their variants can be used to regulate transcription. In this review, we examine the roles of some general transcription factors in the assembly of the basal transcription complex, as well as functions of TATA boxes of the model plant A. thaliana. We review examples showing not only the involvement of TATA boxes in the initiation of transcription machinery assembly but also their indirect participation in plant adaptation to environmental conditions in responses to light and other phenomena. Examples of an influence of the expression levels of A. thaliana TBP1 and TBP2 on morphological traits of the plants are also examined. We summarize available functional data on these two early players that trigger the assembly of transcription machinery. This information will deepen the understanding of the mechanisms underlying transcription by Pol II in plants and will help to utilize the functions of the interaction of TBP with TATA boxes in practice.
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Barth A, Opanasyuk O, Peulen TO, Felekyan S, Kalinin S, Sanabria H, Seidel CAM. Unraveling multi-state molecular dynamics in single-molecule FRET experiments. I. Theory of FRET-lines. J Chem Phys 2022; 156:141501. [PMID: 35428384 PMCID: PMC9014241 DOI: 10.1063/5.0089134] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Conformational dynamics of biomolecules are of fundamental importance for their function. Single-molecule studies of Förster Resonance Energy Transfer (smFRET) between a tethered donor and acceptor dye pair are a powerful tool to investigate the structure and dynamics of labeled molecules. However, capturing and quantifying conformational dynamics in intensity-based smFRET experiments remains challenging when the dynamics occur on the sub-millisecond timescale. The method of multiparameter fluorescence detection addresses this challenge by simultaneously registering fluorescence intensities and lifetimes of the donor and acceptor. Together, two FRET observables, the donor fluorescence lifetime τD and the intensity-based FRET efficiency E, inform on the width of the FRET efficiency distribution as a characteristic fingerprint for conformational dynamics. We present a general framework for analyzing dynamics that relates average fluorescence lifetimes and intensities in two-dimensional burst frequency histograms. We present parametric relations of these observables for interpreting the location of FRET populations in E–τD diagrams, called FRET-lines. To facilitate the analysis of complex exchange equilibria, FRET-lines serve as reference curves for a graphical interpretation of experimental data to (i) identify conformational states, (ii) resolve their dynamic connectivity, (iii) compare different kinetic models, and (iv) infer polymer properties of unfolded or intrinsically disordered proteins. For a simplified graphical analysis of complex kinetic networks, we derive a moment-based representation of the experimental data that decouples the motion of the fluorescence labels from the conformational dynamics of the biomolecule. Importantly, FRET-lines facilitate exploring complex dynamic models via easily computed experimental observables. We provide extensive computational tools to facilitate applying FRET-lines.
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Affiliation(s)
- Anders Barth
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Oleg Opanasyuk
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Thomas-Otavio Peulen
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Suren Felekyan
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Stanislav Kalinin
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Hugo Sanabria
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29631, USA
| | - Claus A. M. Seidel
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, Düsseldorf, Germany
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6
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Medina E, R Latham D, Sanabria H. Unraveling protein's structural dynamics: from configurational dynamics to ensemble switching guides functional mesoscale assemblies. Curr Opin Struct Biol 2021; 66:129-138. [PMID: 33246199 PMCID: PMC7965259 DOI: 10.1016/j.sbi.2020.10.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 12/18/2022]
Abstract
Evidence regarding protein structure and function manifest the imperative role that dynamics play in proteins, underlining reconsideration of the unanimated sequence-to-structure-to-function paradigm. Structural dynamics portray a heterogeneous energy landscape described by conformational ensembles where each structural representation can be responsible for unique functions or enable macromolecular assemblies. Using the human p27/Cdk2/Cyclin A ternary complex as an example, we highlight the vital role of intramolecular and intermolecular dynamics for target recognition, binding, and inhibition as a critical modulator of cell division. Rapidly sampling configurations is critical for the population of different conformational ensembles encoding functional roles. To garner this knowledge, we present how the integration of (sub)ensemble and single-molecule fluorescence spectroscopy with molecular dynamic simulations can characterize structural dynamics linking the heterogeneous ensembles to function. The incorporation of dynamics into the sequence-to-structure-to-function paradigm promises to assist in tackling various challenges, including understanding the formation and regulation of mesoscale assemblies inside cells.
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Affiliation(s)
- Exequiel Medina
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago 7800003, Chile; Department of Physics and Astronomy, Clemson University, Clemson 29634, United States
| | - Danielle R Latham
- Department of Physics and Astronomy, Clemson University, Clemson 29634, United States
| | - Hugo Sanabria
- Department of Physics and Astronomy, Clemson University, Clemson 29634, United States.
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7
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Wang L, Song F, Zhu W, Fu J, Dong Z, Xu P. The stage-specific long non-coding RNAs and mRNAs identification and analysis during early development of common carp, Cyprinus carpio. Genomics 2020; 113:20-28. [PMID: 33271329 DOI: 10.1016/j.ygeno.2020.11.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 11/23/2020] [Accepted: 11/29/2020] [Indexed: 10/22/2022]
Abstract
Cyprinus carpio is considered an alternative vertebrate fish model to zebrafish. However, systemic times-series research on the lncRNAs and mRNAs during early development of C. carpio has not been reported yet. This study provides the first long non-coding RNA (lncRNA)-mRNA expression profiles during six main early development stages (2 h post-fertilization hpf, 6 hpf, 12 hpf, 20 hpf, 64 hpf and 1 day post-hatching). A total of 51,979 lncRNAs were identified. We screened the top 10 abundance lncRNAs and mRNAs and stage-specific lncRNAs and mRNAs (specificity measure SPM > 0.9). We identified significant differentially expressed lncRNAs and mRNAs (|log2 (fold change)| ≥ 1 and false discovery rate FDR of <0.05). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified numerous signaling pathways. Additionally, the lncRNA-mRNA co-regulated network analysis of two lncRNAs (lncrps25 and malat1) and two mRNAs (mitf and troponin T) were investigated. Our results provide new insight into the role of lncRNAs and mRNAs, and would advance the understanding of lncRNA-mediated mechanisms in early development of fish.
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Affiliation(s)
- Lanmei Wang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
| | - Feibiao Song
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Wenbin Zhu
- Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
| | - Jianjun Fu
- Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
| | - Zaijie Dong
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China.
| | - Pao Xu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China.
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8
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Kramm K, Schröder T, Gouge J, Vera AM, Gupta K, Heiss FB, Liedl T, Engel C, Berger I, Vannini A, Tinnefeld P, Grohmann D. DNA origami-based single-molecule force spectroscopy elucidates RNA Polymerase III pre-initiation complex stability. Nat Commun 2020; 11:2828. [PMID: 32504003 PMCID: PMC7275037 DOI: 10.1038/s41467-020-16702-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 05/13/2020] [Indexed: 01/03/2023] Open
Abstract
The TATA-binding protein (TBP) and a transcription factor (TF) IIB-like factor are important constituents of all eukaryotic initiation complexes. The reason for the emergence and strict requirement of the additional initiation factor Bdp1 in the RNA polymerase (RNAP) III system, however, remained elusive. A poorly studied aspect in this context is the effect of DNA strain arising from DNA compaction and transcriptional activity on initiation complex formation. We made use of a DNA origami-based force clamp to follow the assembly of human initiation complexes in the RNAP II and RNAP III systems at the single-molecule level under piconewton forces. We demonstrate that TBP-DNA complexes are force-sensitive and TFIIB is sufficient to stabilise TBP on a strained promoter. In contrast, Bdp1 is the pivotal component that ensures stable anchoring of initiation factors, and thus the polymerase itself, in the RNAP III system. Thereby, we offer an explanation for the crucial role of Bdp1 for the high transcriptional output of RNAP III.
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Affiliation(s)
- Kevin Kramm
- Single-Molecule Biochemistry Lab, Institute of Microbiology and Archaea Centre, University of Regensburg, 93053, Regensburg, Germany
| | - Tim Schröder
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, 80539, München, Germany
| | - Jerome Gouge
- Division of Structural Biology, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Andrés Manuel Vera
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, 80539, München, Germany
| | - Kapil Gupta
- Bristol Synthetic Biology Centre BrisSynBio, Biomedical Sciences, University of Bristol, 1 Tankard's Close, Clifton, BS8 1TD, UK
| | - Florian B Heiss
- Regensburg Center of Biochemistry (RCB), University of Regensburg, 93053, Regensburg, Germany
| | - Tim Liedl
- Faculty of Physics and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München, 80539, Munich, Germany
| | - Christoph Engel
- Regensburg Center of Biochemistry (RCB), University of Regensburg, 93053, Regensburg, Germany
| | - Imre Berger
- Bristol Synthetic Biology Centre BrisSynBio, Biomedical Sciences, University of Bristol, 1 Tankard's Close, Clifton, BS8 1TD, UK
| | - Alessandro Vannini
- Division of Structural Biology, The Institute of Cancer Research, London, SW7 3RP, UK
- Human Technopole Foundation, Centre of Structural Biology, 20157, Milan, Italy
| | - Philip Tinnefeld
- Department of Chemistry and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, 80539, München, Germany
| | - Dina Grohmann
- Single-Molecule Biochemistry Lab, Institute of Microbiology and Archaea Centre, University of Regensburg, 93053, Regensburg, Germany.
- Regensburg Center of Biochemistry (RCB), University of Regensburg, 93053, Regensburg, Germany.
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9
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Kramm K, Endesfelder U, Grohmann D. A Single-Molecule View of Archaeal Transcription. J Mol Biol 2019; 431:4116-4131. [PMID: 31207238 DOI: 10.1016/j.jmb.2019.06.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 05/27/2019] [Accepted: 06/06/2019] [Indexed: 01/03/2023]
Abstract
The discovery of the archaeal domain of life is tightly connected to an in-depth analysis of the prokaryotic RNA world. In addition to Carl Woese's approach to use the sequence of the 16S rRNA gene as phylogenetic marker, the finding of Karl Stetter and Wolfram Zillig that archaeal RNA polymerases (RNAPs) were nothing like the bacterial RNAP but are more complex enzymes that resemble the eukaryotic RNAPII was one of the key findings supporting the idea that archaea constitute the third major branch on the tree of life. This breakthrough in transcriptional research 40years ago paved the way for in-depth studies of the transcription machinery in archaea. However, although the archaeal RNAP and the basal transcription factors that fine-tune the activity of the RNAP during the transcription cycle are long known, we still lack information concerning the architecture and dynamics of archaeal transcription complexes. In this context, single-molecule measurements were instrumental as they provided crucial insights into the process of transcription initiation, the architecture of the initiation complex and the dynamics of mobile elements of the RNAP. In this review, we discuss single-molecule approaches suitable to examine molecular mechanisms of transcription and highlight findings that shaped our understanding of the archaeal transcription apparatus. We furthermore explore the possibilities and challenges of next-generation single-molecule techniques, for example, super-resolution microscopy and single-molecule tracking, and ask whether these approaches will ultimately allow us to investigate archaeal transcription in vivo.
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Affiliation(s)
- Kevin Kramm
- Institute of Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Ulrike Endesfelder
- Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiology and LOEWE Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch-Str. 16, 35043 Marburg, Germany
| | - Dina Grohmann
- Institute of Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
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