1
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Miyasaka S, Kitada R, Kokubo T. Taf1 N-terminal domain 2 (TAND2) of TFIID promotes formation of stable and mobile unstable TBP-TATA complexes. Gene 2023; 889:147800. [PMID: 37716588 DOI: 10.1016/j.gene.2023.147800] [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] [Received: 06/16/2023] [Revised: 09/05/2023] [Accepted: 09/12/2023] [Indexed: 09/18/2023]
Abstract
In eukaryotes, TATA-binding protein (TBP) occupancy of the core promoter globally correlates with transcriptional activity of class II genes. Elucidating how TBP is delivered to the TATA box or TATA-like element is crucial to understand the mechanisms of transcriptional regulation. A previous study demonstrated that the inhibitory DNA binding (IDB) surface of human TBP plays an indispensable role during the two-step formation of the TBP-TATA complex, first assuming an unstable and unbent intermediate conformation, and subsequently converting slowly to a stable and bent conformation. The DNA binding property of TBP is altered by physical contact of this surface with TBP regulators. In the present study, we examined whether the interaction between Taf1 N-terminal domain 2 (TAND2) and the IDB surface affected DNA binding property of yeast TBP by exploiting TAND2-fused TBP derivatives. TAND2 promoted formation of two distinct types of TBP-TATA complexes, which we arbitrarily designated as complex I and II. While complex I was stable and similar to the well-characterized original TBP-TATA complex, complex II was unstable and moved along DNA. Removal of TAND2 from TBP after complex formation revealed that continuous contact of TAND2 with the IDB surface was required for formation of complex II but not complex I. Further, TFIIA could be incorporated into the complex of TAND2-fused TBP and the TATA box, which was dependent on the amino-terminal non-conserved region of TBP, implying that this region could facilitate the exchange between TAND2 and TFIIA on the IDB surface. Collectively, these findings provide novel insights into the mechanism by which TBP is relieved from the interaction with TAND to bind the TATA box or TATA-like element within promoter-bound TFIID.
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Affiliation(s)
- Shinji Miyasaka
- Molecular and Cellular Biology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Kanagawa, Japan
| | - Ryota Kitada
- Molecular and Cellular Biology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Kanagawa, Japan
| | - Tetsuro Kokubo
- Molecular and Cellular Biology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Kanagawa, Japan.
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2
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Liao CC, Wang YS, Pi WC, Wang CH, Wu YM, Chen WY, Hsia KC. Structural convergence endows nuclear transport receptor Kap114p with a transcriptional repressor function toward TATA-binding protein. Nat Commun 2023; 14:5518. [PMID: 37684250 PMCID: PMC10491584 DOI: 10.1038/s41467-023-41206-9] [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] [Received: 11/28/2022] [Accepted: 08/24/2023] [Indexed: 09/10/2023] Open
Abstract
The transcription factor TATA-box binding protein (TBP) modulates gene expression in nuclei. This process requires the involvement of nuclear transport receptors, collectively termed karyopherin-β (Kap-β) in yeast, and various regulatory factors. In previous studies we showed that Kap114p, a Kap-β that mediates nuclear import of yeast TBP (yTBP), modulates yTBP-dependent transcription. However, how Kap114p associates with yTBP to exert its multifaceted functions has remained elusive. Here, we employ single-particle cryo-electron microscopy to determine the structure of Kap114p in complex with the core domain of yTBP (yTBPC). Remarkably, Kap114p wraps around the yTBPC N-terminal lobe, revealing a structure resembling transcriptional regulators in complex with TBP, suggesting convergent evolution of the two protein groups for a common function. We further demonstrate that Kap114p sequesters yTBP away from promoters, preventing a collapse of yTBP dynamics required for yeast responses to environmental stress. Hence, we demonstrate that nuclear transport receptors represent critical elements of the transcriptional regulatory network.
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Affiliation(s)
- Chung-Chi Liao
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and National Defense Medical Center, Taipei, 11490, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Yi-Sen Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Wen-Chieh Pi
- Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan
| | - Chun-Hsiung Wang
- Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan
| | - Yi-Min Wu
- Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan
| | - Wei-Yi Chen
- Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan.
- Cancer and Immunology Research Center, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan.
| | - Kuo-Chiang Hsia
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and National Defense Medical Center, Taipei, 11490, Taiwan.
- Institute of Molecular Biology, Academia Sinica, Taipei, 11529, Taiwan.
- Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan.
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3
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Liao CC, Shankar S, Pi WC, Chang CC, Ahmed GR, Chen WY, Hsia KC. Karyopherin Kap114p-mediated trans-repression controls ribosomal gene expression under saline stress. EMBO Rep 2020; 21:e48324. [PMID: 32484313 DOI: 10.15252/embr.201948324] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 04/16/2020] [Accepted: 04/30/2020] [Indexed: 01/01/2023] Open
Abstract
Nuclear accessibility of transcription factors controls gene expression, co-regulated by Ran-dependent nuclear localization and a competitive regulatory network. Here, we reveal that nuclear import factor-facilitated transcriptional repression attenuates ribosome biogenesis under chronic salt stress. Kap114p, one of the karyopherin-βs (Kap-βs) that mediates nuclear import of yeast TATA-binding protein (yTBP), exhibits a yTBP-binding affinity four orders of magnitude greater than its counterparts and suppresses binding of yTBP with DNA. Our crystal structure of Kap114p reveals an extensively negatively charged concave surface, accounting for high-affinity basic-protein binding. KAP114 knockout in yeast leads to a high-salt growth defect, with transcriptomic analyses revealing that Kap114p modulates expression of genes associated with ribosomal biogenesis by suppressing yTBP binding to target promoters, a trans-repression mechanism we attribute to reduced nuclear Ran levels under salinity stress. Our findings reveal that Ran integrates the nuclear transport pathway and transcription regulatory network, allowing yeast to respond to environmental stresses.
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Affiliation(s)
- Chung-Chi Liao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Sahana Shankar
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Wen-Chieh Pi
- Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Chih-Chia Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | | | - Wei-Yi Chen
- Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Kuo-Chiang Hsia
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang-Ming University, Taipei, Taiwan
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4
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Heiss G, Ploetz E, Voith von Voithenberg L, Viswanathan R, Glaser S, Schluesche P, Madhira S, Meisterernst M, Auble DT, Lamb DC. Conformational changes and catalytic inefficiency associated with Mot1-mediated TBP-DNA dissociation. Nucleic Acids Res 2019; 47:2793-2806. [PMID: 30649478 PMCID: PMC6451094 DOI: 10.1093/nar/gky1322] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 12/21/2018] [Accepted: 01/07/2019] [Indexed: 11/12/2022] Open
Abstract
The TATA-box Binding Protein (TBP) plays a central role in regulating gene expression and is the first step in the process of pre-initiation complex (PIC) formation on promoter DNA. The lifetime of TBP at the promoter site is controlled by several cofactors including the Modifier of transcription 1 (Mot1), an essential TBP-associated ATPase. Based on ensemble measurements, Mot1 can use adenosine triphosphate (ATP) hydrolysis to displace TBP from DNA and various models for how this activity is coupled to transcriptional regulation have been proposed. However, the underlying molecular mechanism of Mot1 action is not well understood. In this work, the interaction of Mot1 with the DNA/TBP complex was investigated by single-pair Förster resonance energy transfer (spFRET). Upon Mot1 binding to the DNA/TBP complex, a transition in the DNA/TBP conformation was observed. Hydrolysis of ATP by Mot1 led to a conformational change but was not sufficient to efficiently disrupt the complex. SpFRET measurements of dual-labeled DNA suggest that Mot1's ATPase activity primes incorrectly oriented TBP for dissociation from DNA and additional Mot1 in solution is necessary for TBP unbinding. These findings provide a framework for understanding how the efficiency of Mot1's catalytic activity is tuned to establish a dynamic pool of TBP without interfering with stable and functional TBP-containing complexes.
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Affiliation(s)
- Gregor Heiss
- Department für Chemie, Center for Nanoscience (CeNS), Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Evelyn Ploetz
- Department für Chemie, Center for Nanoscience (CeNS), Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Lena Voith von Voithenberg
- Department für Chemie, Center for Nanoscience (CeNS), Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Ramya Viswanathan
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Samson Glaser
- Department für Chemie, Center for Nanoscience (CeNS), Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Peter Schluesche
- Department für Chemie, Center for Nanoscience (CeNS), Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Sushi Madhira
- Department für Chemie, Center for Nanoscience (CeNS), Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Michael Meisterernst
- Institut für Molekulare Tumorbiologie, Westfälische Wilhelms-Universität, Münster 48149, Germany
| | - David T Auble
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Don C Lamb
- Department für Chemie, Center for Nanoscience (CeNS), Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM), Ludwig-Maximilians-Universität, München 81377, Germany
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5
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Zarrabi N, Schluesche P, Meisterernst M, Börsch M, Lamb DC. Analyzing the Dynamics of Single TBP-DNA-NC2 Complexes Using Hidden Markov Models. Biophys J 2018; 115:2310-2326. [PMID: 30527334 DOI: 10.1016/j.bpj.2018.11.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 11/12/2018] [Accepted: 11/12/2018] [Indexed: 10/27/2022] Open
Abstract
Single-pair Förster resonance energy transfer (spFRET) has become an important tool for investigating conformational dynamics in biological systems. To extract dynamic information from the spFRET traces measured with total internal reflection fluorescence microscopy, we extended the hidden Markov model (HMM) approach. In our extended HMM analysis, we incorporated the photon-shot noise from camera-based systems into the HMM. Thus, the variance in Förster resonance energy transfer (FRET) efficiency of the various states, which is typically a fitted parameter, is explicitly included in the analysis estimated from the number of detected photons. It is also possible to include an additional broadening of the FRET state, which would then only reflect the inherent flexibility of the dynamic biological systems. This approach is useful when comparing the dynamics of individual molecules for which the total intensities vary significantly. We used spFRET with the extended HMM analysis to investigate the dynamics of TATA-box-binding protein (TBP) on promoter DNA in the presence of negative cofactor 2 (NC2). We compared the dynamics of two promoters as well as DNAs of different length and labeling location. For the adenovirus major late promoter, four FRET states were observed; three states correspond to different conformations of the DNA in the TBP-DNA-NC2 complex and a four-state model in which the complex has shifted along the DNA. The HMM analysis revealed that the states are connected via a linear, four-well model. For the H2B promoter, more complex dynamics were observed. By clustering the FRET states detected with the HMM analysis, we could compare the general dynamics observed for the two promoter sequences. We observed that the dynamics from a stretched DNA conformation to a bent conformation for the two promoters were similar, whereas the bent conformation of the TBP-DNA-NC2 complex for the H2B promoter is approximately three times more stable than for the adenovirus major late promoter.
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Affiliation(s)
- Nawid Zarrabi
- Physikalisches Institut, University of Stuttgart, Stuttgart, Baden-Württemberg, Germany; Single-Molecule Microscopy Group, Jena University Hospital, Jena, Thuringia, Germany
| | - Peter Schluesche
- Department Chemie, Center for Nano Science, Center for Integrated Protein Science, and Nanosystems Initiative München, Ludwig-Maximilians-Universität Munich, Munich, Bavaria, Germany
| | - Michael Meisterernst
- GSF-National Research Center for Environment and Health, Gene Expression, Munich, Bavaria, Germany; Institute of Molecular Tumor Biology, Faculty of Medicine, University of Muenster, Muenster, North Rhine-Westphalia, Germany
| | - Michael Börsch
- Physikalisches Institut, University of Stuttgart, Stuttgart, Baden-Württemberg, Germany; Single-Molecule Microscopy Group, Jena University Hospital, Jena, Thuringia, Germany
| | - Don C Lamb
- Department Chemie, Center for Nano Science, Center for Integrated Protein Science, and Nanosystems Initiative München, Ludwig-Maximilians-Universität Munich, Munich, Bavaria, Germany.
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6
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Viswanathan R, True JD, Auble DT. Molecular Mechanism of Mot1, a TATA-binding Protein (TBP)-DNA Dissociating Enzyme. J Biol Chem 2016; 291:15714-26. [PMID: 27255709 DOI: 10.1074/jbc.m116.730366] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Indexed: 11/06/2022] Open
Abstract
The essential Saccharomyces cerevisiae ATPase Mot1 globally regulates transcription by impacting the genomic distribution and activity of the TATA-binding protein (TBP). In vitro, Mot1 forms a ternary complex with TBP and DNA and can use ATP hydrolysis to dissociate the TBP-DNA complex. Prior work suggested an interaction between the ATPase domain and a functionally important segment of DNA flanking the TATA sequence. However, how ATP hydrolysis facilitates removal of TBP from DNA is not well understood, and several models have been proposed. To gain insight into the Mot1 mechanism, we dissected the role of the flanking DNA segment by biochemical analysis of complexes formed using DNAs with short single-stranded gaps. In parallel, we used a DNA tethered cleavage approach to map regions of Mot1 in proximity to the DNA under different conditions. Our results define non-equivalent roles for bases within a broad segment of flanking DNA required for Mot1 action. Moreover, we present biochemical evidence for two distinct conformations of the Mot1 ATPase, the detection of which can be modulated by ATP analogs as well as DNA sequence flanking the TATA sequence. We also show using purified complexes that Mot1 dissociation of a stable, high affinity TBP-DNA interaction is surprisingly inefficient, suggesting how other transcription factors that bind to TBP may compete with Mot1. Taken together, these results suggest that TBP-DNA affinity as well as other aspects of promoter sequence influence Mot1 function in vivo.
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Affiliation(s)
- Ramya Viswanathan
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Jason D True
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - David T Auble
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
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7
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True JD, Muldoon JJ, Carver MN, Poorey K, Shetty SJ, Bekiranov S, Auble DT. The Modifier of Transcription 1 (Mot1) ATPase and Spt16 Histone Chaperone Co-regulate Transcription through Preinitiation Complex Assembly and Nucleosome Organization. J Biol Chem 2016; 291:15307-19. [PMID: 27226635 DOI: 10.1074/jbc.m116.735134] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Indexed: 11/06/2022] Open
Abstract
Modifier of transcription 1 (Mot1) is a conserved and essential Swi2/Snf2 ATPase that can remove TATA-binding protein (TBP) from DNA using ATP hydrolysis and in so doing exerts global effects on transcription. Spt16 is also essential and functions globally in transcriptional regulation as a component of the facilitates chromatin transcription (FACT) histone chaperone complex. Here we demonstrate that Mot1 and Spt16 regulate a largely overlapping set of genes in Saccharomyces cerevisiae. As expected, Mot1 was found to control TBP levels at co-regulated promoters. In contrast, Spt16 did not affect TBP recruitment. On a global scale, Spt16 was required for Mot1 promoter localization, and Mot1 also affected Spt16 localization to genes. Interestingly, we found that Mot1 has an unanticipated role in establishing or maintaining the occupancy and positioning of nucleosomes at the 5' ends of genes. Spt16 has a broad role in regulating chromatin organization in gene bodies, including those nucleosomes affected by Mot1. These results suggest that the large scale overlap in Mot1 and Spt16 function arises from a combination of both their unique and shared functions in transcription complex assembly and chromatin structure regulation.
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Affiliation(s)
- Jason D True
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Joseph J Muldoon
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Melissa N Carver
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Kunal Poorey
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Savera J Shetty
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - Stefan Bekiranov
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
| | - David T Auble
- From the Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, Virginia 22908
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8
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Butryn A, Schuller JM, Stoehr G, Runge-Wollmann P, Förster F, Auble DT, Hopfner KP. Structural basis for recognition and remodeling of the TBP:DNA:NC2 complex by Mot1. eLife 2015; 4. [PMID: 26258880 PMCID: PMC4565979 DOI: 10.7554/elife.07432] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 08/08/2015] [Indexed: 12/28/2022] Open
Abstract
Swi2/Snf2 ATPases remodel substrates such as nucleosomes and transcription complexes to control a wide range of DNA-associated processes, but detailed structural information on the ATP-dependent remodeling reactions is largely absent. The single subunit remodeler Mot1 (modifier of transcription 1) dissociates TATA box-binding protein (TBP):DNA complexes, offering a useful system to address the structural mechanisms of Swi2/Snf2 ATPases. Here, we report the crystal structure of the N-terminal domain of Mot1 in complex with TBP, DNA, and the transcription regulator negative cofactor 2 (NC2). Our data show that Mot1 reduces DNA:NC2 interactions and unbends DNA as compared to the TBP:DNA:NC2 state, suggesting that Mot1 primes TBP:NC2 displacement in an ATP-independent manner. Electron microscopy and cross-linking data suggest that the Swi2/Snf2 domain of Mot1 associates with the upstream DNA and the histone fold of NC2, thereby revealing parallels to some nucleosome remodelers. This study provides a structural framework for how a Swi2/Snf2 ATPase interacts with its substrate DNA:protein complex. DOI:http://dx.doi.org/10.7554/eLife.07432.001 An organism’s DNA contains thousands of genes, not all of which are active at the same time. Cells use a number of methods to carefully control when particular genes are switched on or off. For example, proteins called transcription factors can activate a gene by binding to particular regions of DNA called promoters. One such transcription factor is called the TATA-binding protein (TBP for short). Mot1 is a remodeling enzyme that can form a “complex” with TBP by binding to it, and in doing so remove TBP from DNA. This silences the genes at those sites. The freed TBP can then bind to other promoters that lack Mot1 and activate the genes found there. In 2011, researchers revealed the structure of the complex formed between TBP and Mot1 after TBP has been detached from DNA. However, the structure of the complex that forms while TBP is still bound to the DNA molecule was not known. Butryn et al. – including several of the researchers involved in the 2011 work – have now described the structure of this complex using X-ray crystallography and electron microscopy. Another protein called negative cofactor 2 is also part of the complex, and helps to stabilize it. Butryn et al. found that Mot1 reduces the strength of the interactions between DNA and both TBP and negative cofactor 2. Binding to TBP and negative cofactor 2 causes the DNA molecule to bend; however, if Mot1 is also in the complex, the DNA becomes less bent. By making these changes, Mot1 is likely to prime TBP to detach from the DNA. Since the current structures do not yet reveal the atomic structure of Mot1’s ATP dependent DNA motor domain, the next challenge is to visualize the entire complex at atomic resolution. DOI:http://dx.doi.org/10.7554/eLife.07432.002
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Affiliation(s)
- Agata Butryn
- Gene Center, Department of Biochemistry, Ludwig Maximilian University, Munich, Germany
| | - Jan M Schuller
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, , Germany
| | - Gabriele Stoehr
- Gene Center, Department of Biochemistry, Ludwig Maximilian University, Munich, Germany
| | - Petra Runge-Wollmann
- Gene Center, Department of Biochemistry, Ludwig Maximilian University, Munich, Germany
| | - Friedrich Förster
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, , Germany
| | - David T Auble
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, United States
| | - Karl-Peter Hopfner
- Gene Center, Department of Biochemistry, Ludwig Maximilian University, Munich, Germany
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9
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Koster M, Snel B, Timmers H. Genesis of Chromatin and Transcription Dynamics in the Origin of Species. Cell 2015; 161:724-36. [DOI: 10.1016/j.cell.2015.04.033] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Indexed: 11/15/2022]
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10
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Koster MJE, Timmers HTM. Regulation of anti-sense transcription by Mot1p and NC2 via removal of TATA-binding protein (TBP) from the 3'-end of genes. Nucleic Acids Res 2014; 43:143-52. [PMID: 25432956 PMCID: PMC4288163 DOI: 10.1093/nar/gku1263] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The activity and dynamic nature of TATA-binding protein (TBP) crucial to RNA polymerase II-mediated transcription is under control of the Mot1p and NC2 complexes. Here we show that both TBP regulatory factors play ‘hidden’ roles in ensuring transcription fidelity by restricting anti-sense non-coding RNA (ncRNA) synthesis. Production of anti-sense ncRNA transcripts is suppressed by Mot1p- and NC2-mediated release of TBP from binding sites at the 3′-end of genes. In this, Mot1p and NC2 collaborate with the Nrd1p–Nab3p–Sen1p (NNS) complex that terminates the synthesis of anti-sense ncRNAs. In several cases anti-sense ncRNA expression interferes with expression of the cognate sense transcript. Our data reveal a novel regulatory mechanism to suppress anti-sense ncRNA expression and pre-initiation complex (PIC) formation at spurious sites.
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Affiliation(s)
- Maria J E Koster
- Department of Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, 3584 CG, Utrecht, The Netherlands
| | - H Th Marc Timmers
- Department of Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, 3584 CG, Utrecht, The Netherlands
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11
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Layer JH, Weil PA. Direct TFIIA-TFIID protein contacts drive budding yeast ribosomal protein gene transcription. J Biol Chem 2013; 288:23273-94. [PMID: 23814059 DOI: 10.1074/jbc.m113.486829] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
We have previously shown that yeast TFIID provides coactivator function on the promoters of ribosomal protein-encoding genes (RPGs) by making direct contact with the transactivator repressor activator protein 1 (Rap1). Further, our structural studies of assemblies generated with purified Rap1, TFIID, and TFIIA on RPG enhancer-promoter DNA indicate that Rap1-TFIID interaction induces dramatic conformational rearrangements of enhancer-promoter DNA and TFIID-bound TFIIA. These data indicate a previously unknown yet critical role for yeast TFIIA in the integration of activator-TFIID contacts with promoter conformation and downstream preinitiation complex formation and/or function. Here we describe the use of systematic mutagenesis to define how specific TFIIA contacts contribute to these processes. We have verified that TFIIA is required for RPG transcription in vivo and in vitro, consistent with the existence of a critical Rap1-TFIIA-TFIID interaction network. We also identified essential points of contact for TFIIA and Rap1 within the Rap1 binding domain of the Taf4 subunit of TFIID. These data suggest a mechanism for how interactions between TFIID, TFIIA, and Rap1 contribute to the high rate of transcription initiation seen on RPGs in vivo.
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Affiliation(s)
- Justin H Layer
- Department of Molecular Physiology and Biophysics, School of Medicine, Vanderbilt University, Nashville, Tennessee 37232-0615, USA
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12
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Moyle-Heyrman G, Viswanathan R, Widom J, Auble DT. Two-step mechanism for modifier of transcription 1 (Mot1) enzyme-catalyzed displacement of TATA-binding protein (TBP) from DNA. J Biol Chem 2012; 287:9002-12. [PMID: 22298788 DOI: 10.1074/jbc.m111.333484] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The TATA box binding protein (TBP) is a central component of the transcription preinitiation complex, and its occupancy at a promoter is correlated with transcription levels. The TBP-promoter DNA complex contains sharply bent DNA and its interaction lifetime is limited by the ATP-dependent TBP displacement activity of the Snf2/Swi2 ATPase Mot1. Several mechanisms for Mot1 action have been proposed, but how it catalyzes TBP removal from DNA is unknown. To better understand the Mot1 mechanism, native gel electrophoresis and FRET were used to determine how Mot1 affects the trajectory of DNA in the TBP-DNA complex. Strikingly, in the absence of ATP, Mot1 acts to unbend DNA, whereas TBP remains closely associated with the DNA in a stable Mot1-TBP-DNA ternary complex. Interestingly, and in contrast to full-length Mot1, the isolated Mot1 ATPase domain binds DNA, and its affinity for DNA is nucleotide-dependent, suggesting parallels between the Mot1 mechanism and DNA translocation-based mechanisms of chromatin remodeling enzymes. Based on these findings, a model is presented for Mot1 that links a DNA conformational change with ATP-induced DNA translocation.
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13
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Spedale G, Meddens CA, Koster MJE, Ko CW, van Hooff SR, Holstege FCP, Timmers HTM, Pijnappel WWMP. Tight cooperation between Mot1p and NC2β in regulating genome-wide transcription, repression of transcription following heat shock induction and genetic interaction with SAGA. Nucleic Acids Res 2011; 40:996-1008. [PMID: 21976730 PMCID: PMC3273795 DOI: 10.1093/nar/gkr784] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
TATA-binding protein (TBP) is central to the regulation of eukaryotic transcription initiation. Recruitment of TBP to target genes can be positively regulated by one of two basal transcription factor complexes: SAGA or TFIID. Negative regulation of TBP promoter association can be performed by Mot1p or the NC2 complex. Recent evidence suggests that Mot1p, NC2 and TBP form a DNA-dependent protein complex. Here, we compare the functions of Mot1p and NC2βduring basal and activated transcription using the anchor-away technique for conditional nuclear depletion. Genome-wide expression analysis indicates that both proteins regulate a highly similar set of genes. Upregulated genes were enriched for SAGA occupancy, while downregulated genes preferred TFIID binding. Mot1p and NC2β depletion during heat shock resulted in failure to downregulate gene expression after initial activation, which was accompanied by increased TBP and RNA pol II promoter occupancies. Depletion of Mot1p or NC2β displayed preferential synthetic lethality with the TBP-interaction module of SAGA. Our results support the model that Mot1p and NC2β directly cooperate in vivo to regulate TBP function, and that they are involved in maintaining basal expression levels as well as in resetting gene expression after induction by stress.
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Affiliation(s)
- Gianpiero Spedale
- Molecular Cancer Research, Netherlands Proteomics Centre, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG, Utrecht, The Netherlands
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14
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Abstract
Chromatin remodelling is the ATP-dependent change in nucleosome organisation driven by Snf2 family ATPases. The biochemistry of this process depends on the behaviours of ATP-dependent motor proteins and their dynamic nucleosome substrates, which brings significant technical and conceptual challenges. Steady progress has been made in characterising the polypeptides of which these enzymes are comprised. Divergence in the sequences of different subfamilies of Snf2-related proteins suggests that the motors are adapted for different functions. Recently, structural insights have suggested that the Snf2 ATPase acts as a context-sensitive DNA translocase. This may have arisen as a means to enable efficient access to DNA in the high density of the eukaryotic nucleus. How the enzymes engage nucleosomes and how the network of noncovalent interactions within the nucleosome respond to the force applied remains unclear, and it remains prudent to recognise the potential for both DNA distortions and dynamics within the underlying histone octamer structure.
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Affiliation(s)
- Andrew Flaus
- Centre for Chromosome Biology, Biochemistry, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland.
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15
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Viswanathan R, Auble DT. One small step for Mot1; one giant leap for other Swi2/Snf2 enzymes? BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2011; 1809:488-96. [PMID: 21658482 DOI: 10.1016/j.bbagrm.2011.05.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 05/14/2011] [Accepted: 05/20/2011] [Indexed: 12/13/2022]
Abstract
The TATA-binding protein (TBP) is a major target for transcriptional regulation. Mot1, a Swi2/Snf2-related ATPase, dissociates TBP from DNA in an ATP dependent process. The experimental advantages of this relatively simple reaction have been exploited to learn more about how Swi2/Snf2 ATPases function biochemically. However, many unanswered questions remain and fundamental aspects of the Mot1 mechanism are still under debate. Here, we review the available data and integrate the results with structural and biochemical studies of related enzymes to derive a model for Mot1's catalytic action consistent with the broad literature on enzymes in this family. We propose that the Mot1 ATPase domain is tethered to TBP by a flexible, spring-like linker of alpha helical hairpins. The linker juxtaposes the ATPase domain such that it can engage duplex DNA on one side of the TBP-DNA complex. This allows the ATPase to employ short-range, nonprocessive ATP-driven DNA tracking to pull or push TBP off its DNA site. DNA translocation is a conserved property of ATPases in the broader enzyme family. As such, the model explains how a structurally and functionally conserved ATPase domain has been put to use in a very different context than other enzymes in the Swi2/Snf2 family. This article is part of a Special Issue entitled:Snf2/Swi2 ATPase structure and function.
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Affiliation(s)
- Ramya Viswanathan
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, VA 22908, USA
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16
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Abstract
TATA binding protein (TBP) plays a central role in transcription complex assembly and is regulated by a variety of transcription factors, including Mot1. Mot1 is an essential protein in Saccharomyces cerevisiae that exerts both negative and positive effects on transcription via interactions with TBP. It contains two conserved regions important for TBP interactions, another conserved region that hydrolyzes ATP to remove TBP from DNA, and a fourth conserved region with unknown function. Whether these regions contribute equally to transcriptional regulation genome-wide is unknown. Here, we employ a transient-replacement assay using deletion derivatives in the conserved regions of Mot1 to investigate their contributions to gene regulation throughout the S. cerevisiae genome. These four regions of Mot1 are essential for growth and are generally required for all Mot1-regulated genes. Loss of the ATPase region, but not other conserved regions, caused TBP to redistribute away from a subset of Mot1-inhibited genes, leading to decreased expression of those genes. A corresponding increase in TBP occupancy and expression occurred at another set of genes that are normally Mot1 independent. The data suggest that Mot1 uses ATP hydrolysis to redistribute accessible TBP away from intrinsically preferred sites to other sites of intrinsically low preference.
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17
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The TATA box regulates TATA-binding protein (TBP) dynamics in vivo. Trends Biochem Sci 2010; 35:309-14. [DOI: 10.1016/j.tibs.2010.01.007] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Revised: 01/25/2010] [Accepted: 01/26/2010] [Indexed: 11/22/2022]
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18
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Azmy YY, Gupta A, Pugh BF. Computational modelling of genome-wide [corrected] transcription assembly networks using a fluidics analogy. PLoS One 2008; 3:e3095. [PMID: 18769485 PMCID: PMC2518210 DOI: 10.1371/journal.pone.0003095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Accepted: 08/04/2008] [Indexed: 11/29/2022] Open
Abstract
Understanding how a myriad of transcription regulators work to modulate mRNA output at thousands of genes remains a fundamental challenge in molecular biology. Here we develop a computational tool to aid in assessing the plausibility of gene regulatory models derived from genome-wide expression profiling of cells mutant for transcription regulators. mRNA output is modelled as fluid flow in a pipe lattice, with assembly of the transcription machinery represented by the effect of valves. Transcriptional regulators are represented as external pressure heads that determine flow rate. Modelling mutations in regulatory proteins is achieved by adjusting valves' on/off settings. The topology of the lattice is designed by the experimentalist to resemble the expected interconnection between the modelled agents and their influence on mRNA expression. Users can compare multiple lattice configurations so as to find the one that minimizes the error with experimental data. This computational model provides a means to test the plausibility of transcription regulation models derived from large genomic data sets.
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Affiliation(s)
- Yousry Y. Azmy
- Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Anshuman Gupta
- Department of Academic Services & Emerging Technologies, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - B. Franklin Pugh
- Center for Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail:
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19
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van Werven FJ, van Bakel H, van Teeffelen HAAM, Altelaar AFM, Koerkamp MG, Heck AJR, Holstege FCP, Timmers HTM. Cooperative action of NC2 and Mot1p to regulate TATA-binding protein function across the genome. Genes Dev 2008; 22:2359-69. [PMID: 18703679 DOI: 10.1101/gad.1682308] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Promoter recognition by TATA-binding protein (TBP) is an essential step in the initiation of RNA polymerase II (pol II) mediated transcription. Genetic and biochemical studies in yeast have shown that Mot1p and NC2 play important roles in inhibiting TBP activity. To understand how TBP activity is regulated in a genome-wide manner, we profiled the binding of TBP, NC2, Mot1p, TFIID, SAGA, and pol II across the yeast genome using chromatin immunoprecipitation (ChIP)-chip for cells in exponential growth and during reprogramming of transcription. We find that TBP, NC2, and Mot1p colocalize at transcriptionally active pol II core promoters. Relative binding of NC2alpha and Mot1p is higher at TATA promoters, whereas NC2beta has a preference for TATA-less promoters. In line with the ChIP-chip data, we isolated a stable TBP-NC2-Mot1p-DNA complex from chromatin extracts. ATP hydrolysis releases NC2 and DNA from the Mot1p-TBP complex. In vivo experiments indicate that promoter dissociation of TBP and NC2 is highly dynamic, which is dependent on Mot1p function. Based on these results, we propose that NC2 and Mot1p cooperate to dynamically restrict TBP activity on transcribed promoters.
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Affiliation(s)
- Folkert J van Werven
- Department of Physiological Chemistry, University Medical Center Utrecht, 3584 CG Utrecht, The Netherlands
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20
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Arnett DR, Jennings JL, Tabb DL, Link AJ, Weil PA. A proteomics analysis of yeast Mot1p protein-protein associations: insights into mechanism. Mol Cell Proteomics 2008; 7:2090-106. [PMID: 18596064 DOI: 10.1074/mcp.m800221-mcp200] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Yeast Mot1p, a member of the Snf2 ATPase family of proteins, is a transcriptional regulator that has the unusual ability to both repress and activate mRNA gene transcription. To identify interactions with other proteins that may assist Mot1p in its regulatory processes, Mot1p was purified from replicate yeast cell extracts, and Mot1p-associated proteins were identified by coupled multidimensional liquid chromatography and tandem mass spectrometry. Using this approach we generated a catalog of Mot1p-interacting proteins. Mot1p interacts with a range of transcriptional co-regulators as well as proteins involved in chromatin remodeling. We propose that interaction with such a wide range of proteins may be one mechanism through which Mot1p subserves its roles as a transcriptional activator and repressor.
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Affiliation(s)
- Diana R Arnett
- Department of Molecular Physiology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0615, USA
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21
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Bendjennat M, Weil PA. The transcriptional repressor activator protein Rap1p is a direct regulator of TATA-binding protein. J Biol Chem 2008; 283:8699-710. [PMID: 18195009 DOI: 10.1074/jbc.m709436200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Essentially all nuclear eukaryotic gene transcription depends upon the function of the transcription factor TATA-binding protein (TBP). Here we show that the abundant, multifunctional DNA binding transcription factor repressor activator protein Rap1p interacts directly with TBP. TBP-Rap1p binding occurs efficiently in vivo at physiological expression levels, and in vitro analyses confirm that this is a direct interaction. The DNA binding domains of the two proteins mediate interaction between TBP and Rap1p. TBP-Rap1p complex formation inhibits TBP binding to TATA promoter DNA. Alterations in either Rap1p or TBP levels modulate mRNA gene transcription in vivo. We propose that Rap1p represents a heretofore unrecognized regulator of TBP.
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Affiliation(s)
- Mourad Bendjennat
- Department of Molecular Physiology and Biophysics, Vanderbilt University, School of Medicine, Nashville, TN 37232-0615, USA
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22
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Mousson F, Kolkman A, Pijnappel WWMP, Timmers HTM, Heck AJR. Quantitative proteomics reveals regulation of dynamic components within TATA-binding protein (TBP) transcription complexes. Mol Cell Proteomics 2007; 7:845-52. [PMID: 18087068 DOI: 10.1074/mcp.m700306-mcp200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Affinity purification in combination with isotope labeling of proteins has proven to be a powerful method to discriminate specific from nonspecific interactors. However, in the standard SILAC (stable isotope labeling by amino acids in cell culture) approach dynamic components may easily be assigned as nonspecific. We compared two affinity purification protocols, which in combination revealed information on the dynamics of protein complexes. We focused on the central component in eukaryotic transcription, the human TATA-binding protein, which is involved in different complexes. All known TATA-binding protein-associated factors (TAFs) were detected as specific interactors. Interestingly one of them, BTAF1, exchanged significantly in cell extracts during the affinity purification. The other TAFs did not display this behavior. Cell cycle synchronization showed that BTAF1 exchange was regulated during mitosis. The combination of the two affinity purification protocols allows a quantitative approach to identify transient components in any protein complex.
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Affiliation(s)
- Florence Mousson
- Department of Physiological Chemistry, University Medical Centre Utrecht, Universiteitsweg 100, 3584CG Utrecht, The Netherlands
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23
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Huisinga KL, Pugh BF. A TATA binding protein regulatory network that governs transcription complex assembly. Genome Biol 2007; 8:R46. [PMID: 17407552 PMCID: PMC1896006 DOI: 10.1186/gb-2007-8-4-r46] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Revised: 12/22/2006] [Accepted: 04/02/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Eukaryotic genes are controlled by proteins that assemble stepwise into a transcription complex. How the individual biochemically defined assembly steps are coordinated and applied throughout a genome is largely unknown. Here, we model and experimentally test a portion of the assembly process involving the regulation of the TATA binding protein (TBP) throughout the yeast genome. RESULTS Biochemical knowledge was used to formulate a series of coupled TBP regulatory reactions involving TFIID, SAGA, NC2, Mot1, and promoter DNA. The reactions were then linked to basic segments of the transcription cycle and modeled computationally. A single framework was employed, allowing the contribution of specific steps to vary from gene to gene. Promoter binding and transcriptional output were measured genome-wide using ChIP-chip and expression microarray assays. Mutagenesis was used to test the framework by shutting down specific parts of the network. CONCLUSION The model accounts for the regulation of TBP at most transcriptionally active promoters and provides a conceptual tool for interpreting genome-wide data sets. The findings further demonstrate the interconnections of TBP regulation on a genome-wide scale.
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Affiliation(s)
- Kathryn L Huisinga
- Center for Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Department of Biology, Washington University, Saint Louis, MO 63130, USA
| | - B Franklin Pugh
- Center for Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
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24
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Abstract
In eukaryotes, the core promoter serves as a platform for the assembly of transcription preinitiation complex (PIC) that includes TFIIA, TFIIB, TFIID, TFIIE, TFIIF, TFIIH, and RNA polymerase II (pol II), which function collectively to specify the transcription start site. PIC formation usually begins with TFIID binding to the TATA box, initiator, and/or downstream promoter element (DPE) found in most core promoters, followed by the entry of other general transcription factors (GTFs) and pol II through either a sequential assembly or a preassembled pol II holoenzyme pathway. Formation of this promoter-bound complex is sufficient for a basal level of transcription. However, for activator-dependent (or regulated) transcription, general cofactors are often required to transmit regulatory signals between gene-specific activators and the general transcription machinery. Three classes of general cofactors, including TBP-associated factors (TAFs), Mediator, and upstream stimulatory activity (USA)-derived positive cofactors (PC1/PARP-1, PC2, PC3/DNA topoisomerase I, and PC4) and negative cofactor 1 (NC1/HMGB1), normally function independently or in combination to fine-tune the promoter activity in a gene-specific or cell-type-specific manner. In addition, other cofactors, such as TAF1, BTAF1, and negative cofactor 2 (NC2), can also modulate TBP or TFIID binding to the core promoter. In general, these cofactors are capable of repressing basal transcription when activators are absent and stimulating transcription in the presence of activators. Here we review the roles of these cofactors and GTFs, as well as TBP-related factors (TRFs), TAF-containing complexes (TFTC, SAGA, SLIK/SALSA, STAGA, and PRC1) and TAF variants, in pol II-mediated transcription, with emphasis on the events occurring after the chromatin has been remodeled but prior to the formation of the first phosphodiester bond.
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Affiliation(s)
- Mary C Thomas
- Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4935, USA
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25
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Gumbs OH, Padgett RA, Dayie KT. Fluorescence and solution NMR study of the active site of a 160-kDa group II intron ribozyme. RNA (NEW YORK, N.Y.) 2006; 12:1693-707. [PMID: 16894219 PMCID: PMC1557703 DOI: 10.1261/rna.137006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Accepted: 06/29/2006] [Indexed: 05/11/2023]
Abstract
We have reconstructed the group II intron from Pylaiella littoralis (PL) into a hydrolytic ribozyme, comprising domains 1-3 (D123) connected in cis plus domain 5 (D5) supplied in trans that efficiently cleaves spliced exon substrates. Using a novel gel-based fluorescence assay and nuclear magnetic resonance (NMR) spectroscopy, we monitored the direct binding of D5 to D123, characterized the kinetics of the spliced exon hydrolysis reaction (which is mechanistically analogous to the reverse of the second catalytic step of splicing), and identified the binding surface of D123 on D5. This PL ribozyme acts as an RNA endonuclease even at low monovalent (100 mM KCl) and divalent ion concentrations (1-10 mM MgCl(2)). This is in contrast to other group II intron ribozyme systems that require high levels of salt, making NMR analysis problematic. D5 binds tightly to D123 with a K(d) of 650 +/- 250 nM, a K(m) of approximately 300 nM, and a K(cat) of 0.02 min(-1) under single turnover conditions. Within the approximately 160-kDa D123-D5 binary complex, site-specific binding to D123 leads to dramatic chemical shift perturbation of residues localized to the tetraloop and internal bulge within D5, suggesting a structural switch model for D5-assisted splicing. This minimal ribozyme thus recapitulates the essential features of the reverse of the second catalytic step and represents a well-behaved system for ongoing high-resolution structural work to complement folding and catalytic functional studies.
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Affiliation(s)
- Orlando H Gumbs
- Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195, USA
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26
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Sprouse RO, Brenowitz M, Auble DT. Snf2/Swi2-related ATPase Mot1 drives displacement of TATA-binding protein by gripping DNA. EMBO J 2006; 25:1492-504. [PMID: 16541100 PMCID: PMC1440317 DOI: 10.1038/sj.emboj.7601050] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2005] [Accepted: 02/20/2006] [Indexed: 11/09/2022] Open
Abstract
Mot1 is a conserved Snf2/Swi2-related transcriptional regulator that uses ATP hydrolysis to displace TATA-binding protein (TBP) from DNA. Several models of the enzymatic mechanism have been proposed, including Mot1-catalyzed distortion of TBP structure, competition between Mot1 and DNA for the TBP DNA-binding surface, and ATP-driven translocation of Mot1 along DNA. Here, DNase I footprinting studies provide strong support for a 'DNA-based' mechanism of Mot1, which we propose involves ATP-driven DNA translocation. Mot1 forms an asymmetric complex with the TBP core domain (TBPc)-DNA complex, contacting DNA both upstream and within the major groove of the TATA Box. Contact with upstream DNA is required for Mot1-mediated displacement of TBPc from DNA. Using the SsoRad54-DNA complex as a model, DNA-binding residues in Mot1 were identified that are critical for Mot1-TBPc-DNA complex formation and catalytic activity, thus placing Mot1 mechanistically within the helicase superfamily. We also report a novel ATP-independent TBPc displacement activity for Mot1 and describe conformational heterogeneity in the Mot1 ATPase, which is likely a general feature of other enzymes in this class.
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Affiliation(s)
- Rebekka O Sprouse
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, VA, USA
| | - Michael Brenowitz
- Department of Biochemistry, The Albert Einstein College of Medicine, Bronx, NY, USA
| | - David T Auble
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, VA, USA
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, 1300 Jefferson Park Avenue, Room 6213, Charlottesville, VA 22908-0733, USA. Tel.: +1 434 243 2629; Fax: +1 434 924 5069; E-mail:
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27
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Biswas D, Yu Y, Mitra D, Stillman DJ. Genetic interactions between Nhp6 and Gcn5 with Mot1 and the Ccr4-Not complex that regulate binding of TATA-binding protein in Saccharomyces cerevisiae. Genetics 2005; 172:837-49. [PMID: 16272410 PMCID: PMC1456248 DOI: 10.1534/genetics.105.050245] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Our previous work suggests that the Nhp6 HMGB protein stimulates RNA polymerase II transcription via the TATA-binding protein TBP and that Nhp6 functions in the same functional pathway as the Gcn5 histone acetyltransferase. In this report we examine the genetic relationship between Nhp6 and Gcn5 with the Mot1 and Ccr4-Not complexes, both of which have been implicated in regulating DNA binding by TBP. We find that combining either a nhp6ab or a gcn5 mutation with mot1, ccr4, not4, or not5 mutations results in lethality. Combining spt15 point mutations (in TBP) with either mot1 or ccr4 also results in either a growth defect or lethality. Several of these synthetic lethalities can be suppressed by overexpression of TFIIA, TBP, or Nhp6, suggesting that these genes facilitate formation of the TBP-TFIIA-DNA complex. The growth defect of a not5 mutant can be suppressed by a mot1 mutant. HO gene expression is reduced by nhp6ab, gcn5, or mot1 mutations, and the additive decreases in HO mRNA levels in nhp6ab mot1 and gcn5 mot1 strains suggest different modes of action. Chromatin immunoprecipitation experiments show decreased binding of TBP to promoters in mot1 mutants and a further decrease when combined with either nhp6ab or gcn5 mutations.
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Affiliation(s)
- Debabrata Biswas
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA
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28
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Dürr H, Körner C, Müller M, Hickmann V, Hopfner KP. X-ray structures of the Sulfolobus solfataricus SWI2/SNF2 ATPase core and its complex with DNA. Cell 2005; 121:363-73. [PMID: 15882619 DOI: 10.1016/j.cell.2005.03.026] [Citation(s) in RCA: 210] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2004] [Revised: 02/28/2005] [Accepted: 03/17/2005] [Indexed: 11/22/2022]
Abstract
SWI2/SNF2 ATPases remodel chromatin or other DNA:protein complexes by a poorly understood mechanism that involves ATP-dependent DNA translocation and generation of superhelical torsion. Crystal structures of a dsDNA-translocating SWI2/SNF2 ATPase core from Sulfolobus solfataricus reveal two helical SWI2/SNF2 specific subdomains, fused to a DExx box helicase-related ATPase core. Fully base paired duplex DNA binds along a central cleft via both minor groove strands, indicating that SWI2/SNF2 ATPases travel along the dsDNA minor groove without strand separation. A structural switch, linking DNA binding and the active site DExx motif, may account for the stimulation of ATPase activity by dsDNA. Our results suggest that torque in remodeling processes is generated by an ATP-driven screw motion of DNA along the active site cleft. The structures also redefine SWI2/SNF2 functional motifs and uncover unexpected structural correlation of mutations in Cockayne and X-linked mental retardation syndromes.
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Affiliation(s)
- Harald Dürr
- Gene Center and Department of Chemistry and Biochemistry, University of Munich, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
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29
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Yagi Y, Ip YT. Helicase89B is a Mot1p/BTAF1 homologue that mediates an antimicrobial response in Drosophila. EMBO Rep 2005; 6:1088-94. [PMID: 16200050 PMCID: PMC1371033 DOI: 10.1038/sj.embor.7400542] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2004] [Revised: 08/11/2005] [Accepted: 08/17/2005] [Indexed: 11/09/2022] Open
Abstract
We have identified a novel component, Helicase89B, that is required for the inducible antimicrobial response in Drosophila larvae by means of a P-element insertional genetic screen. Helicase89B belongs to the Mot1p/BTAF1 subfamily of SNF2-like ATPases. This subfamily can interact with TATA-binding proteins, but whether the interaction leads to gene activation or repression is being debated. We found that Helicase89B is required for the inducible expression of antimicrobial peptide genes but not for the inducible expression of heat-shock genes. The antimicrobial peptide genes are activated by the Toll and immune deficiency (IMD) signalling pathways. Genetic experiments show that Helicase89B acts downstream of DIF and Relish, the two nuclear factor-kappaB (NF-kappaB)-related transcription factors that mediate Toll- and IMD-stimulated antimicrobial response. Thus, Helicase89B positively regulates gene expression during innate immune response and may act as a link between NF-kappaB-related transcription factors and the basal transcription machinery.
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Affiliation(s)
- Yoshimasa Yagi
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, Massachusetts 01605, USA
| | - Y Tony Ip
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, Massachusetts 01605, USA
- Tel: +1 508 856 5136; Fax: +1 508 856 4289; E-mail:
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30
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Klejman MP, Zhao X, van Schaik FMA, Herr W, Timmers HTM. Mutational analysis of BTAF1-TBP interaction: BTAF1 can rescue DNA-binding defective TBP mutants. Nucleic Acids Res 2005; 33:5426-36. [PMID: 16179647 PMCID: PMC1236718 DOI: 10.1093/nar/gki850] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The BTAF1 transcription factor interacts with TATA-binding protein (TBP) to form the B–TFIID complex, which is involved in RNA polymerase II transcription. Here, we present an extensive mapping study of TBP residues involved in BTAF1 interaction. This shows that residues in the concave, DNA-binding surface of TBP are important for BTAF1 binding. In addition, BTAF1 interacts with residues in helix 2 on the convex side of TBP as assayed in protein–protein and in DNA-binding assays. BTAF1 drastically changes the TATA-box binding specificity of TBP, as it is able to recruit DNA-binding defective TBP mutants to both TATA-containing and TATA-less DNA. Interestingly, other helix 2 interacting factors, such as TFIIA and NC2, can also stabilize mutant TBP binding to DNA. In contrast, TFIIB which interacts with a distinct surface of TBP does not display this activity. Since many proteins contact helix 2 of TBP, this provides a molecular basis for mutually exclusive TBP interactions and stresses the importance of this structural element for eukaryotic transcription.
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Affiliation(s)
| | - Xuemei Zhao
- Cold Spring Harbor LaboratoryCold Spring Harbor, NY 11724, USA
| | | | - Winship Herr
- Cold Spring Harbor LaboratoryCold Spring Harbor, NY 11724, USA
| | - H. Th. Marc Timmers
- To whom correspondence should be addressed. Tel: +31 30 253 8981; Fax: + 31 30 253 9035;
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31
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van Oevelen CJC, van Teeffelen HAAM, Timmers HTM. Differential requirement of SAGA subunits for Mot1p and Taf1p recruitment in gene activation. Mol Cell Biol 2005; 25:4863-72. [PMID: 15923605 PMCID: PMC1140607 DOI: 10.1128/mcb.25.12.4863-4872.2005] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transcription activation in yeast (Saccharomyces cerevisiae) involves ordered recruitment of transcription factor complexes, such as TFIID, SAGA, and Mot1p. Previously, we showed that both Mot1p and Taf1p are recruited to the HXT2 and HXT4 genes, which encode hexose transporter proteins. Here, we show that SAGA also binds to the HXT2 and HXT4 promoters and plays a pivotal role in the recruitment of Mot1p and Taf1p. The deletion of either SPT3 or SPT8 reduces Mot1p binding to HXT2 and HXT4. Surprisingly, the deletion of GCN5 reduces Taf1p binding to both promoters. When GCN5 is deleted in spt3Delta or spt8Delta strains, neither Mot1p nor Taf1p binds, and this results in a diminished recruitment of TATA binding protein and polymerase II to the HXT4 but not the HXT2 promoter. This is reflected by the SAGA-dependent expression of HXT4. In contrast, SAGA-independent induction of HXT2 suggests a functional redundancy with other factors. A functional interplay of different SAGA subunits with Mot1p and Taf1p was supported by phenotypic analysis of MOT1 SAGA or TAF1/SAGA double mutant strains, which revealed novel genetic interactions between MOT1 and SPT8 and between TAF1 and GCN5. In conclusion, our data demonstrate functional links between SAGA, Mot1p, and TFIID in HXT gene regulation.
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Affiliation(s)
- Chris J C van Oevelen
- Department of Physiological Chemistry, Division of Biomedical Genetics, University Medical Centre Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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32
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Gilfillan S, Stelzer G, Piaia E, Hofmann MG, Meisterernst M. Efficient Binding of NC2·TATA-binding Protein to DNA in the Absence of TATA. J Biol Chem 2005; 280:6222-30. [PMID: 15574413 DOI: 10.1074/jbc.m406343200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Negative cofactor 2 (NC2) forms a stable complex with TATA-binding protein (TBP) on promoters. This prevents the assembly of transcription factor (TF) IIA and TFIIB and leads to repression of RNA polymerase II transcription. Here we have revisited the interactions of NC2.TBP with DNA. We show that NC2.TBP complexes exhibit a significantly reduced preference for TATA box sequences compared with TBP and TBP.TFIIA complexes. In chromatin immunoprecipitations, NC2 is found on a variety of human TATA-containing and TATA-less promoters. Substantial amounts of NC2 are present in a complex with TBP in bulk chromatin. A complex of NC2.TBP displays a K(D) for DNA of approximately 2 x 10(-9) m for a 35-bp major late promoter oligonucleotide. While preferentially recognizing promoter-bound TBP, NC2 also accelerates TBP binding to promoters and stabilizes TBP.DNA complexes. Our data suggest that NC2 controls TBP binding and maintenance on DNA that is largely independent of a canonical TATA sequence.
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Affiliation(s)
- Siv Gilfillan
- Gene Expression, Institute of Molecular Immunology, GSF-National Research Center for Environment and Health, Marchionini-Strasse 25, D-81377 Munich, Germany
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33
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Klejman MP, Pereira LA, van Zeeburg HJT, Gilfillan S, Meisterernst M, Timmers HTM. NC2alpha interacts with BTAF1 and stimulates its ATP-dependent association with TATA-binding protein. Mol Cell Biol 2004; 24:10072-82. [PMID: 15509807 PMCID: PMC525489 DOI: 10.1128/mcb.24.22.10072-10082.2004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transcriptional activity of the TATA-binding protein (TBP) is controlled by a variety of proteins. The BTAF1 protein (formerly known as TAF(II)170/TAF-172 and the human ortholog of Saccharomyces cerevisiae Mot1p) and the NC2 complex composed of NC2alpha (DRAP1) and NC2beta (Dr1) are able to bind to TBP directly and regulate RNA polymerase II transcription both positively and negatively. Here, we present evidence that the NC2alpha subunit interacts with BTAF1. In contrast, the NC2beta subunit is not able to associate with BTAF1 and seems to interfere with the BTAF1-TBP interaction. Addition of NC2alpha or the NC2 complex can stimulate the ability of BTAF1 to interact with TBP. This function is dependent on the presence of ATP in cell extracts but does not involve the ATPase activity of BTAF1 nor phosphorylation of NC2alpha. Together, our results constitute the first evidence of the physical cooperation between BTAF1 and NC2alpha in TBP regulation and provide a framework to understand transcription functions of NC2alpha and NC2beta in vivo.
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Affiliation(s)
- Marcin P Klejman
- Department of Physiological Chemistry, Division of Biomedical Genetics, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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34
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Flaus A, Owen-Hughes T. Mechanisms for ATP-dependent chromatin remodelling: farewell to the tuna-can octamer? Curr Opin Genet Dev 2004; 14:165-73. [PMID: 15196463 DOI: 10.1016/j.gde.2004.01.007] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
ATP-dependent chromatin remodelling enzymes act to alter chromatin structure during gene regulation. Studies of the ATPase motors that drive these enzymes support the notion that they function as ATP-dependent DNA translocases with limited processivity. The action of these enzymes on nucleosomes results in the alteration of nucleosome positioning and structure. Recent studies have shown that ATP-dependent chromatin remodelling can also either remove or exchange histone dimers between nucleosomes. This provides a new means by which the incorporation of histone variants can be directed. Additional observations support roles for ATP-dependent remodelling enzymes throughout the transcription cycle.
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Affiliation(s)
- Andrew Flaus
- Division of Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
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35
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Geisberg JV, Struhl K. Cellular Stress Alters the Transcriptional Properties of Promoter-Bound Mot1-TBP Complexes. Mol Cell 2004; 14:479-89. [PMID: 15149597 DOI: 10.1016/j.molcel.2004.05.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Revised: 03/16/2004] [Accepted: 03/30/2004] [Indexed: 11/28/2022]
Abstract
Mot1 associates with transcriptionally active promoters, and it directly affects transcriptional activity in a positive or negative manner, depending on the gene. As determined by sequential chromatin immunoprecipitation, Mot1 co-occupies promoters with TBP, but not with TFIIB, TFIIA, or Pol II when cells are grown in normal conditions. This strongly suggests that the Mot1-TBP complex is transcriptionally inactive, and hence is in dynamic equilibrium with transcriptionally active forms of TBP. Surprisingly, in response to heat shock and other forms of environmental stress, Mot1 co-occupies promoters with TFIIB and elongation-competent Pol II, but not with TFIIA. This suggests that functional preinitiation complexes can contain Mot1 instead of TFIIA in vivo. Thus, Mot1-TBP complexes can exist in active and inactive forms that are regulated by environmental stress.
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Affiliation(s)
- Joseph V Geisberg
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
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36
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Pereira LA, Klejman MP, Ruhlmann C, Kavelaars F, Oulad-Abdelghani M, Timmers HTM, Schultz P. Molecular architecture of the basal transcription factor B-TFIID. J Biol Chem 2004; 279:21802-7. [PMID: 14988402 DOI: 10.1074/jbc.m313519200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BTAF1 (formerly named TAF(II)170/TAF-172) is an essential, evolutionarily conserved member of the SNF2-like family of ATPase proteins and together with TATA-binding protein (TBP) forms the B-TFIID complex. BTAF1 has been proposed to play a key role in the dynamic regulation of TBP function in RNA polymerase II transcription. We have determined the structure of native B-TFIID purified from human cells by electron microscopy and by image analysis of single particles at a resolution of 28 A. B-TFIID is 15 x 9 nm in size and is organized into a large domain of about 170 kDa, which can be subdivided into two domains. Extending from this domain is a long thumb, which in turn is divided into subdomains of about 25, 15, and 35 kDa, the largest of which is located at the end of the thumb. Immunolabeling experiments localize the extreme carboxyl terminus of BTAF1 within the 170-kDa domain, whereas the amino terminus and TBP co-localize to the end of the protruding thumb. The central portion of BTAF1 localizes to the base of the thumb. Comparison of the native B-TFIID with its recombinant form shows that both share a similar domain organization. Collectively, these data provide the first structural model of the B-TFIID complex and map its key functional domains.
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Affiliation(s)
- Lloyd A Pereira
- Department of Physiological Chemistry, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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37
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Pereira LA, Klejman MP, Timmers HTM. Roles for BTAF1 and Mot1p in dynamics of TATA-binding protein and regulation of RNA polymerase II transcription. Gene 2003; 315:1-13. [PMID: 14557059 DOI: 10.1016/s0378-1119(03)00714-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Regulation of RNA polymerase II (pol II) transcription is a highly dynamic process requiring the coordinated interaction of an array of regulatory proteins. Central to this process is the TATA-binding protein (TBP), the key component of the multiprotein complex TFIID. Interaction of TBP with core promoters nucleates the assembly of the preinitiation complex and subsequent recruitment of pol II. Despite recent advances in our understanding of the dynamic nature of the pol II transcription apparatus, the dynamics of TBP function on pol II promoters has remained largely unexplored. Human BTAF1 (TAF(II)170/TAF-172) and its yeast ortholog, Mot1p, are evolutionarily conserved members of the SNF2-like family of ATPase proteins. Genetic identification of Mot1p as a repressor of pol II transcription was supported by findings that Mot1p and BTAF1 could dissociate TBP from TATA DNA complexes using the energy of ATP hydrolysis. Recent data have revealed new aspects of BTAF1 and Mot1p as positive regulators of TBP function in the pol II system and have described new observations relating to their molecular mechanism of action. We review these data in the context of previous findings with particular attention paid to how human BTAF1 and Mot1p may dynamically regulate TBP function on pol II promoters in cells.
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Affiliation(s)
- Lloyd A Pereira
- Laboratory for Physiological Chemistry, Division of Biomedical Genetics, UMC-U, Universiteitsweg 100, 3584 Utrecht CG, The Netherlands
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