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Segev A, Heady L, Crewe M, Madabhushi R. Mapping catalytically engaged TOP2B in neurons reveals the principles of topoisomerase action within the genome. Cell Rep 2024; 43:113809. [PMID: 38377005 DOI: 10.1016/j.celrep.2024.113809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 12/22/2023] [Accepted: 01/31/2024] [Indexed: 02/22/2024] Open
Abstract
We trapped catalytically engaged topoisomerase IIβ (TOP2B) in covalent DNA cleavage complexes (TOP2Bccs) and mapped their positions genome-wide in cultured mouse cortical neurons. We report that TOP2Bcc distribution varies with both nucleosome and compartmental chromosome organization. While TOP2Bccs in gene bodies correlate with their level of transcription, highly expressed genes that lack the usually associated chromatin marks, such as H3K36me3, show reduced TOP2Bccs, suggesting that histone posttranslational modifications regulate TOP2B activity. Promoters with high RNA polymerase II occupancy show elevated TOP2B chromatin immunoprecipitation sequencing signals but low TOP2Bccs, indicating that TOP2B catalytic engagement is curtailed at active promoters. Surprisingly, either poisoning or inhibiting TOP2B increases nascent transcription at most genes and enhancers but reduces transcription within long genes. These effects are independent of transcript length and instead correlate with the presence of intragenic enhancers. Together, these results clarify how cells modulate the catalytic engagement of topoisomerases to affect transcription.
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Affiliation(s)
- Amir Segev
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lance Heady
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Morgan Crewe
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ram Madabhushi
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Peter O' Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Crewe M, Segev A, Rueda R, Madabhushi R. Atypical Modes of CTCF Binding Facilitate Tissue-Specific and Neuronal Activity-Dependent Gene Expression States. Mol Neurobiol 2023:10.1007/s12035-023-03762-5. [PMID: 37979036 DOI: 10.1007/s12035-023-03762-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023]
Abstract
Multivalent binding of CTCF to variable DNA sequences is thought to underlie its ability to mediate diverse cellular functions. CTCF typically binds a 20 base-pair consensus DNA sequence, but the full diversity of CTCF binding sites (CBS) within the genome has not been interrogated. We assessed CTCF occupancy in cultured cortical neurons and observed surprisingly that ~ 22% of CBS lack the consensus CTCF motif. We report here that sequence diversity at most of these atypical CBS involves degeneracy at specific nucleotide positions within the consensus CTCF motif, which likely affect the binding of CTCF zinc fingers 6 and 7. This mode of atypical CTCF binding defines most CBS at gene promoters, as well as CBS that are dynamically altered during neural differentiation and following neuronal stimulation, revealing how atypical CTCF binding could influence gene activity. Dynamic CBS are distributed both within and outside loop anchors and TAD boundaries, suggesting both looping-dependent and independent roles for CTCF. Finally, we describe a second mode of atypical CTCF binding to DNA sequences that are completely unrelated to the consensus CTCF motif, which are enriched within the bodies of tissue-specific genes. These tissue-specific atypical CBS are also enriched in H3K27ac, which marks cis-regulatory elements within chromatin, including enhancers. Overall, these results indicate how atypical CBS could dynamically regulate gene activity patterns during differentiation, development, and in response to environmental cues.
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Affiliation(s)
- Morgan Crewe
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Amir Segev
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Richard Rueda
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ram Madabhushi
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Delint-Ramirez I, Madabhushi R. NPAS4 juggles neuronal activity-dependent transcription and DSB repair with NuA4. Mol Cell 2023; 83:1208-1209. [PMID: 37084713 DOI: 10.1016/j.molcel.2023.03.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 03/20/2023] [Accepted: 03/20/2023] [Indexed: 04/23/2023]
Abstract
In a recent study, Pollina et al.1 discover a new neuron-specific NuA4-TIP60 chromatin remodeling complex that facilitates the repair of activity-induced DNA double-strand breaks (DSBs) in neurons and protects against mutations that accumulate with age and early death.
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Affiliation(s)
- Ilse Delint-Ramirez
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ram Madabhushi
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Delint-Ramirez I, Konada L, Heady L, Rueda R, Jacome ASV, Marlin E, Marchioni C, Segev A, Kritskiy O, Yamakawa S, Reiter AH, Tsai LH, Madabhushi R. Calcineurin dephosphorylates topoisomerase IIβ and regulates the formation of neuronal-activity-induced DNA breaks. Mol Cell 2022; 82:3794-3809.e8. [PMID: 36206766 PMCID: PMC9990814 DOI: 10.1016/j.molcel.2022.09.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 07/27/2022] [Accepted: 09/09/2022] [Indexed: 11/13/2022]
Abstract
Neuronal activity induces topoisomerase IIβ (Top2B) to generate DNA double-strand breaks (DSBs) within the promoters of neuronal early response genes (ERGs) and facilitate their transcription, and yet, the mechanisms that control Top2B-mediated DSB formation are unknown. Here, we report that stimulus-dependent calcium influx through NMDA receptors activates the phosphatase calcineurin to dephosphorylate Top2B at residues S1509 and S1511, which stimulates its DNA cleavage activity and induces it to form DSBs. Exposing mice to a fear conditioning paradigm also triggers Top2B dephosphorylation at S1509 and S1511 in the hippocampus, indicating that calcineurin also regulates Top2B-mediated DSB formation following physiological neuronal activity. Furthermore, calcineurin-Top2B interactions following neuronal activity and sites that incur activity-induced DSBs are preferentially localized at the nuclear periphery in neurons. Together, these results reveal how radial gene positioning and the compartmentalization of activity-dependent signaling govern the position and timing of activity-induced DSBs and regulate gene expression patterns in neurons.
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Affiliation(s)
- Ilse Delint-Ramirez
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lahiri Konada
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lance Heady
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Richard Rueda
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | - Eric Marlin
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Charlotte Marchioni
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Amir Segev
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Oleg Kritskiy
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Satoko Yamakawa
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Li-Huei Tsai
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA.
| | - Ram Madabhushi
- Departments of Psychiatry, Neuroscience, and Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Abstract
The nervous system is vulnerable to genomic instability and mutations in DNA damage response factors lead to numerous developmental and progressive neurological disorders. Despite this, the sources and mechanisms of DNA damage that are most relevant to the development of neuronal dysfunction are poorly understood. The identification of primarily neurological abnormalities in patients with mutations in TDP1 and TDP2 suggest that topoisomerase-mediated DNA damage could be an important underlying source of neuronal dysfunction. Here we review the potential sources of topoisomerase-induced DNA damage in neurons, describe the cellular mechanisms that have evolved to repair such damage, and discuss the importance of these repair mechanisms for preventing neurological disorders.
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Madabhushi R, Kim TK. Emerging themes in neuronal activity-dependent gene expression. Mol Cell Neurosci 2017; 87:27-34. [PMID: 29254824 DOI: 10.1016/j.mcn.2017.11.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 10/23/2017] [Accepted: 11/08/2017] [Indexed: 12/29/2022] Open
Abstract
In this review, we attempt to discuss emerging themes in the regulation of neuronal activity-regulated genes, focusing primarily on an important subset of immediate-early genes. We first discuss earlier studies that have illuminated the role of cis-acting elements within the promoters of immediate-early genes, the corresponding transcription factors that bind these elements, and the roles of major activity-regulated signaling pathways. However, our emphasis is on new studies that have revealed an important role for epigenetic and topological mechanisms, including enhancer-promoter interactions, enhancer RNAs (eRNAs), and activity-induced DNA breaks, that have emerged as important factors that govern the temporal dynamics of activity-induced gene transcription.
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Affiliation(s)
- Ram Madabhushi
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Tae-Kyung Kim
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Madabhushi R, Gao F, Pfenning A, Pan L, Yamakawa S, Seo J, Rueda R, Phan TX, Yamakawa H, Pao PC, Stott R, Gjoneska E, Nott A, Cho S, Kellis M, Tsai LH. Activity-Induced DNA Breaks Govern the Expression of Neuronal Early-Response Genes. Cell 2015; 161:1592-605. [DOI: 10.1016/j.cell.2015.05.032] [Citation(s) in RCA: 364] [Impact Index Per Article: 40.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 01/19/2015] [Accepted: 04/07/2015] [Indexed: 12/16/2022]
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de Anda FC, Rosario AL, Durak O, Tran T, Gräff J, Meletis K, Rei D, Soda T, Madabhushi R, Ginty DD, Kolodkin AL, Tsai LH. Erratum: Corrigendum: Autism spectrum disorder susceptibility gene TAOK2 affects basal dendrite formation in the neocortex. Nat Neurosci 2014. [DOI: 10.1038/nn1214-1840a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
The integrity of our genetic material is under constant attack from numerous endogenous and exogenous agents. The consequences of a defective DNA damage response are well studied in proliferating cells, especially with regards to the development of cancer, yet its precise roles in the nervous system are relatively poorly understood. Here we attempt to provide a comprehensive overview of the consequences of genomic instability in the nervous system. We highlight the neuropathology of congenital syndromes that result from mutations in DNA repair factors and underscore the importance of the DNA damage response in neural development. In addition, we describe the findings of recent studies, which reveal that a robust DNA damage response is also intimately connected to aging and the manifestation of age-related neurodegenerative disorders such as Alzheimer's disease and amyotrophic lateral sclerosis.
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Affiliation(s)
- Ram Madabhushi
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ling Pan
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Li-Huei Tsai
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Seo J, Giusti-Rodríguez P, Zhou Y, Rudenko A, Cho S, Ota KT, Park C, Patzke H, Madabhushi R, Pan L, Mungenast AE, Guan JS, Delalle I, Tsai LH. Activity-dependent p25 generation regulates synaptic plasticity and Aβ-induced cognitive impairment. Cell 2014; 157:486-498. [PMID: 24725413 DOI: 10.1016/j.cell.2014.01.065] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 11/23/2013] [Accepted: 01/23/2014] [Indexed: 12/18/2022]
Abstract
Cyclin-dependent kinase 5 regulates numerous neuronal functions with its activator, p35. Under neurotoxic conditions, p35 undergoes proteolytic cleavage to liberate p25, which has been implicated in various neurodegenerative diseases. Here, we show that p25 is generated following neuronal activity under physiological conditions in a GluN2B- and CaMKIIα-dependent manner. Moreover, we developed a knockin mouse model in which endogenous p35 is replaced with a calpain-resistant mutant p35 (Δp35KI) to prevent p25 generation. The Δp35KI mice exhibit impaired long-term depression and defective memory extinction, likely mediated through persistent GluA1 phosphorylation at Ser845. Finally, crossing the Δp35KI mice with the 5XFAD mouse model of Alzheimer's disease (AD) resulted in an amelioration of β-amyloid (Aβ)-induced synaptic depression and cognitive impairment. Together, these results reveal a physiological role of p25 production in synaptic plasticity and memory and provide new insights into the function of p25 in Aβ-associated neurotoxicity and AD-like pathology.
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Affiliation(s)
- Jinsoo Seo
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Paola Giusti-Rodríguez
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ying Zhou
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Andrii Rudenko
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sukhee Cho
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Kristie T Ota
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Christine Park
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Holger Patzke
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ram Madabhushi
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ling Pan
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alison E Mungenast
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ji-Song Guan
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ivana Delalle
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Li-Huei Tsai
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Broad Institute of Harvard University and Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
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Affiliation(s)
- Li-Huei Tsai
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Ram Madabhushi
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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12
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Madabhushi R, Marians KJ. Actin homolog MreB affects chromosome segregation by regulating topoisomerase IV in Escherichia coli. Mol Cell 2009; 33:171-80. [PMID: 19187760 DOI: 10.1016/j.molcel.2009.01.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Revised: 07/26/2008] [Accepted: 01/09/2009] [Indexed: 10/21/2022]
Abstract
In Escherichia coli, topoisomerase IV, a type II topoisomerase, mediates the resolution of topological linkages between replicated daughter chromosomes and is essential for chromosome segregation. Topo IV activity is restricted to only a short interval late in the cell cycle. However, the mechanism that confers this temporal regulation is unknown. Here we report that the bacterial actin homolog MreB participates in the temporal oscillation of Topo IV activity. We show that mreB mutant strains are deficient in Topo IV activity. In addition, we demonstrate that, depending upon whether it is in a monomeric or polymerized state, MreB affects Topo IV activity differentially. In addition, MreB physically interacts with the ParC subunit of Topo IV. Together, these results may explain how dynamics of the bacterial cytoskeleton are coordinated with the timing of chromosome segregation.
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Affiliation(s)
- Ram Madabhushi
- Program in Molecular Biology, Weill Graduate School of Cornell University, New York, NY 10065, USA
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Lee KM, Miklos I, Du H, Watt S, Szilagyi Z, Saiz JE, Madabhushi R, Penkett CJ, Sipiczki M, Bähler J, Fisher RP. Impairment of the TFIIH-associated CDK-activating kinase selectively affects cell cycle-regulated gene expression in fission yeast. Mol Biol Cell 2005; 16:2734-45. [PMID: 15829570 PMCID: PMC1142420 DOI: 10.1091/mbc.e04-11-0982] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The fission yeast Mcs6-Mcs2-Pmh1 complex, homologous to metazoan Cdk7-cyclin H-Mat1, has dual functions in cell division and transcription: as a partially redundant cyclin-dependent kinase (CDK)-activating kinase (CAK) that phosphorylates the major cell cycle CDK, Cdc2, on Thr-167; and as the RNA polymerase (Pol) II carboxyl-terminal domain (CTD) kinase associated with transcription factor (TF) IIH. We analyzed conditional mutants of mcs6 and pmh1, which activate Cdc2 normally but cannot complete cell division at restrictive temperature and arrest with decreased CTD phosphorylation. Transcriptional profiling by microarray hybridization revealed only modest effects on global gene expression: a one-third reduction in a severe mcs6 mutant after prolonged incubation at 36 degrees C. In contrast, a small subset of transcripts ( approximately 5%) decreased by more than twofold after Mcs6 complex function was compromised. The signature of repressed genes overlapped significantly with those of cell separation mutants sep10 and sep15. Sep10, a component of the Pol II Mediator complex, becomes essential in mcs6 or pmh1 mutant backgrounds. Moreover, transcripts dependent on the forkhead transcription factor Sep1, which are expressed coordinately during mitosis, were repressed in Mcs6 complex mutants, and Mcs6 also interacts genetically with Sep1. Thus, the Mcs6 complex, a direct activator of Cdc2, also influences the cell cycle transcriptional program, possibly through its TFIIH-associated kinase function.
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Affiliation(s)
- Karen M Lee
- Molecular Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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Madabhushi R. DNA sequencing in noncovalently coated capillaries using low viscosity polymer solutions. Methods Mol Biol 2001; 163:309-15. [PMID: 11242955 DOI: 10.1385/1-59259-116-7:309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- R Madabhushi
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, CA, USA
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