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Yadav Y, Dey CS. Ser/Thr phosphatases: One of the key regulators of insulin signaling. Rev Endocr Metab Disord 2022; 23:905-917. [PMID: 35697962 DOI: 10.1007/s11154-022-09727-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/18/2022] [Indexed: 10/18/2022]
Abstract
Protein phosphorylation is an important post-translational modification that regulates several cellular processes including insulin signaling. The evidences so far have already portrayed the importance of balanced actions of kinases and phosphatases in regulating the insulin signaling cascade. Therefore, elucidating the role of both kinases and phosphatases are equally important. Unfortunately, the role of phosphatases is less studied as compared to kinases. Since brain responds to insulin and insulin signaling is reported to be crucial for many neuronal processes, it is important to understand the role of neuronal insulin signaling regulators. Ser/Thr phosphatases seem to play significant roles in regulating neuronal insulin signaling. Therefore, in this review, we discussed the involvement of Ser/Thr phosphatases in regulating insulin signaling and insulin resistance in neuronal system at the backdrop of the same phosphatases in peripheral insulin sensitive tissues.
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Affiliation(s)
- Yamini Yadav
- Kusuma School of Biological Sciences, Indian Institute of Technology, Delhi, New Delhi, 110016, India
| | - Chinmoy Sankar Dey
- Kusuma School of Biological Sciences, Indian Institute of Technology, Delhi, New Delhi, 110016, India.
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2
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Epigenetic Mechanisms in Memory and Cognitive Decline Associated with Aging and Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms222212280. [PMID: 34830163 PMCID: PMC8618067 DOI: 10.3390/ijms222212280] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 12/21/2022] Open
Abstract
Epigenetic mechanisms, which include DNA methylation, a variety of post-translational modifications of histone proteins (acetylation, phosphorylation, methylation, ubiquitination, sumoylation, serotonylation, dopaminylation), chromatin remodeling enzymes, and long non-coding RNAs, are robust regulators of activity-dependent changes in gene transcription. In the brain, many of these epigenetic modifications have been widely implicated in synaptic plasticity and memory formation. Dysregulation of epigenetic mechanisms has been reported in the aged brain and is associated with or contributes to memory decline across the lifespan. Furthermore, alterations in the epigenome have been reported in neurodegenerative disorders, including Alzheimer’s disease. Here, we review the diverse types of epigenetic modifications and their role in activity- and learning-dependent synaptic plasticity. We then discuss how these mechanisms become dysregulated across the lifespan and contribute to memory loss with age and in Alzheimer’s disease. Collectively, the evidence reviewed here strongly supports a role for diverse epigenetic mechanisms in memory formation, aging, and neurodegeneration in the brain.
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Li W, Wu H, Sui S, Wang Q, Xu S, Pang D. Targeting Histone Modifications in Breast Cancer: A Precise Weapon on the Way. Front Cell Dev Biol 2021; 9:736935. [PMID: 34595180 PMCID: PMC8476812 DOI: 10.3389/fcell.2021.736935] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/16/2021] [Indexed: 12/27/2022] Open
Abstract
Histone modifications (HMs) contribute to maintaining genomic stability, transcription, DNA repair, and modulating chromatin in cancer cells. Furthermore, HMs are dynamic and reversible processes that involve interactions between numerous enzymes and molecular components. Aberrant HMs are strongly associated with tumorigenesis and progression of breast cancer (BC), although the specific mechanisms are not completely understood. Moreover, there is no comprehensive overview of abnormal HMs in BC, and BC therapies that target HMs are still in their infancy. Therefore, this review summarizes the existing evidence regarding HMs that are involved in BC and the potential mechanisms that are related to aberrant HMs. Moreover, this review examines the currently available agents and approved drugs that have been tested in pre-clinical and clinical studies to evaluate their effects on HMs. Finally, this review covers the barriers to the clinical application of therapies that target HMs, and possible strategies that could help overcome these barriers and accelerate the use of these therapies to cure patients.
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Affiliation(s)
- Wei Li
- Harbin Medical University Third Hospital: Tumor Hospital of Harbin Medical University, Harbin, China
| | - Hao Wu
- Harbin Medical University Third Hospital: Tumor Hospital of Harbin Medical University, Harbin, China
| | - Shiyao Sui
- Harbin Medical University Third Hospital: Tumor Hospital of Harbin Medical University, Harbin, China
| | - Qin Wang
- Harbin Medical University Third Hospital: Tumor Hospital of Harbin Medical University, Harbin, China
| | - Shouping Xu
- Harbin Medical University Third Hospital: Tumor Hospital of Harbin Medical University, Harbin, China
| | - Da Pang
- Harbin Medical University Third Hospital: Tumor Hospital of Harbin Medical University, Harbin, China.,Heilongjiang Academy of Medical Sciences, Harbin, China
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The role of ALDH2 in tumorigenesis and tumor progression: Targeting ALDH2 as a potential cancer treatment. Acta Pharm Sin B 2021; 11:1400-1411. [PMID: 34221859 PMCID: PMC8245805 DOI: 10.1016/j.apsb.2021.02.008] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/29/2020] [Accepted: 12/01/2020] [Indexed: 12/12/2022] Open
Abstract
A major mitochondrial enzyme for protecting cells from acetaldehyde toxicity is aldehyde dehydrogenase 2 (ALDH2). The correlation between ALDH2 dysfunction and tumorigenesis/growth/metastasis has been widely reported. Either low or high ALDH2 expression contributes to tumor progression and varies among different tumor types. Furthermore, the ALDH2∗2 polymorphism (rs671) is the most common single nucleotide polymorphism (SNP) in Asia. Epidemiological studies associate ALDH2∗2 with tumorigenesis and progression. This study summarizes the essential functions and potential ALDH2 mechanisms in the occurrence, progression, and treatment of tumors in various types of cancer. Our study indicates that ALDH2 is a potential therapeutic target for cancer therapy.
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Key Words
- 4-HNE, 4-hydroxy-2-nonenal
- ALD, alcoholic liver disease
- ALDH2
- ALDH2, aldehyde dehydrogenase 2
- AMPK, AMP-activated protein kinase
- Acetaldehyde
- BCa, bladder cancer
- COUP-TF, chicken ovalbumin upstream promoter-transcription factor
- CRC, colorectal cancer
- CSCs, cancer stem cells
- Cancer
- Cancer therapy
- DFS, disease-free survival
- EC, esophageal cancer
- FA, Fanconi anemia
- FANCD2, Fanconi anemia protein
- GCA, gastric cancer
- HCC, hepatocellular carcinoma
- HDACs, histone deacetylases
- HNC, head and neck cancer
- HNF-4, hepatocyte nuclear factor 4
- HR, homologous recombination
- LCSCs, liver cancer stem cells
- MDA, malondialdehyde
- MDR, multi-drug resistance
- MN, micronuclei
- Metastasis
- NAD, nicotinamide adenine dinucleotide
- NCEs, normochromic erythrocytes
- NER, nucleotide excision repair pathway
- NF-κB, nuclear factor-κB
- NHEJ, non-homologous end-joining
- NRF2, nuclear factor erythroid 2 (NF-E2)-related factor 2
- NRRE, nuclear receptor response element
- NSCLC, non-small-cell lung
- NeG, 1,N2-etheno-dGuo
- OPC, oropharyngeal cancer
- OS, overall survival
- OvCa, ovarian cancer
- PBMC, peripheral blood mononuclear cell
- PC, pancreatic cancer
- PdG, N2-propano-2′-deoxyguanosine
- Polymorphism
- Progression
- REV1, Y-family DNA polymerase
- SCC, squamous cell carcinoma
- TGF-β, transforming growth factor β
- Tumorigenesis
- VHL, von Hippel-Lindau
- ccRCC, clear-cell renal cell carcinomas
- εPKC, epsilon protein kinase C
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Epigenetic-Targeted Treatments for H3K27M-Mutant Midline Gliomas. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1283:73-84. [PMID: 33155139 DOI: 10.1007/978-981-15-8104-5_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Diffuse intrinsic pontine glioma (DIPG) is a lethal midline brainstem tumor that most commonly occurs in children and is genetically defined by substitution of methionine for lysine at site 27 of histone 3 (H3K27M) in the majority of cases. This mutation has since been shown to exert an influence on the posttranslational epigenetic landscape of this disease, with the loss of trimethylation at lysine 27 (H3K27me3) the most common alteration. Based on these findings, a number of drugs targeting these epigenetic changes have been proposed, specifically that alter histone trimethylation, acetylation, or phosphorylation. Various mechanisms have been explored, including inhibition of H327 demethylase and methyltransferase to target trimethylation, inhibition of histone deacetylase (HDAC) and bromodomain and extraterminal (BET) to target acetylation, and inhibition of phosphatase-related enzymes to target phosphorylation. This chapter reviews the current rationales and progress made to date in epigenetically targeting DIPG via these mechanisms.
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Kim LH, Hong ST, Choi KW. Protein phosphatase 2A interacts with Verthandi/Rad21 to regulate mitosis and organ development in Drosophila. Sci Rep 2019; 9:7624. [PMID: 31110215 PMCID: PMC6527568 DOI: 10.1038/s41598-019-44027-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 05/07/2019] [Indexed: 12/20/2022] Open
Abstract
Rad21/Scc1 is a subunit of the cohesin complex implicated in gene regulation as well as sister chromatid cohesion. The level of Rad21/Scc1 must be controlled for proper mitosis and gene expression during development. Here, we identify the PP2A catalytic subunit encoded by microtubule star (mts) as a regulator of Drosophila Rad21/Verthandi (Vtd). Mutations in mts and vtd cause synergistic mitotic defects, including abnormal spindles and loss of nuclei during nuclear division in early embryo. Depletion of Mts and Vtd in developing wing synergistically reduces the Cut protein level, causing severe defects in wing growth. Mts and PP2A subunit Twins (Tws) interact with Vtd protein. Loss of Mts or Tws reduces Vtd protein level. Reduced proteasome function suppresses mitotic defects caused by mutations in mts and vtd. Taken together, this work provides evidence that PP2A is required for mitosis and wing growth by regulating the Vtd level through the proteasomal pathway.
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Affiliation(s)
- Lee-Hyang Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Sung-Tae Hong
- Department of Anatomy & Cell Biology, College of Medicine, Chungnam National University, Daejeon, Republic of Korea.,Department of Medical Science, College of Medicine, Chungnam National University, Daejeon, Republic of Korea
| | - Kwang-Wook Choi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
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Bennett SA, Tanaz R, Cobos SN, Torrente MP. Epigenetics in amyotrophic lateral sclerosis: a role for histone post-translational modifications in neurodegenerative disease. Transl Res 2019; 204:19-30. [PMID: 30391475 PMCID: PMC6331271 DOI: 10.1016/j.trsl.2018.10.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 09/26/2018] [Accepted: 10/09/2018] [Indexed: 02/06/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is the third most common adult onset neurodegenerative disorder worldwide. It is generally characterized by progressive paralysis starting at the limbs ultimately leading to death caused by respiratory failure. There is no cure and current treatments fail to slow the progression of the disease. As such, new treatment options are desperately needed. Epigenetic targets are an attractive possibility because they are reversible. Epigenetics refers to heritable changes in gene expression unrelated to changes in DNA sequence. Three main epigenetic mechanisms include the methylation of DNA, microRNAs and the post-translational modification of histone proteins. Histone modifications occur in many amino acid residues and include phosphorylation, acetylation, methylation as well as other chemical moieties. Recent evidence points to a possible role for epigenetic mechanisms in the etiology of ALS. Here, we review recent advances linking ALS and epigenetics, with a strong focus on histone modifications. Both local and global changes in histone modification profiles are associated with ALS drawing attention to potential targets for future diagnostic and treatment approaches.
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Affiliation(s)
- Seth A Bennett
- Department of Chemistry, Brooklyn College, Brooklyn, NewYork; Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, New York
| | - Royena Tanaz
- Department of Chemistry, Brooklyn College, Brooklyn, NewYork
| | - Samantha N Cobos
- Department of Chemistry, Brooklyn College, Brooklyn, NewYork; Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, NY 10016
| | - Mariana P Torrente
- Department of Chemistry, Brooklyn College, Brooklyn, NewYork; Ph.D. Programs in Chemistry, Biochemistry, and Biology, The Graduate Center of the City University of New York, New York, New York.
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Chen K, Bennett SA, Rana N, Yousuf H, Said M, Taaseen S, Mendo N, Meltser SM, Torrente MP. Neurodegenerative Disease Proteinopathies Are Connected to Distinct Histone Post-translational Modification Landscapes. ACS Chem Neurosci 2018; 9:838-848. [PMID: 29243911 DOI: 10.1021/acschemneuro.7b00297] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD) are devastating neurodegenerative diseases involving the progressive degeneration of neurons. No cure is available for patients diagnosed with these diseases. A prominent feature of both ALS and PD is the accumulation of protein inclusions in the cytoplasm of degenerating neurons; however, the particular proteins constituting these inclusions vary: the RNA-binding proteins TDP-43 and FUS are most notable in ALS, while α-synuclein aggregates into Lewy bodies in PD. In both diseases, genetic causes fail to explain the occurrence of a large proportion of cases, and thus, both are considered mostly sporadic. Despite mounting evidence for a possible role of epigenetics in the occurrence and progression of ALS and PD, epigenetic mechanisms in the context of these diseases remain mostly unexplored. Here we comprehensively delineate histone post-translational modification (PTM) profiles in ALS and PD yeast proteinopathy models. Remarkably, we find distinct changes in histone modification profiles for each. We detect the most striking changes in the context of FUS aggregation: changes in several histone marks support a global decrease in gene transcription. We also detect more modest changes in histone modifications in cells overexpressing TDP-43 or α-synuclein. Our results highlight a great need for the inclusion of epigenetic mechanisms in the study of neurodegeneration. We hope our work will pave the way for the discovery of more effective therapies to treat patients suffering from ALS, PD, and other neurodegenerative diseases.
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Affiliation(s)
- Karen Chen
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
| | - Seth A. Bennett
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
- Graduate Program in Biochemistry, The Graduate Center of the City University of New York, New York, New York 10016, United States
| | - Navin Rana
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
| | - Huda Yousuf
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
| | - Mohamed Said
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
| | - Sadiqa Taaseen
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
| | - Natalie Mendo
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
| | - Steven M. Meltser
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
| | - Mariana P. Torrente
- Chemistry Department of Brooklyn College, Brooklyn, New York 11210, United States
- Ph.D. Programs in Chemistry, Biochemistry, and Biology, The Graduate Center of the City University of New York, New York, New York 10016, United States
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9
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Li Y, Wang C, Cai W, Sengupta S, Zavortink M, Deng H, Girton J, Johansen J, Johansen KM. H2Av facilitates H3S10 phosphorylation but is not required for heat shock-induced chromatin decondensation or transcriptional elongation. Development 2017; 144:3232-3240. [PMID: 28807902 PMCID: PMC5612252 DOI: 10.1242/dev.151134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 07/19/2017] [Indexed: 01/30/2023]
Abstract
A model has been proposed in which JIL-1 kinase-mediated H3S10 and H2Av phosphorylation is required for transcriptional elongation and heat shock-induced chromatin decondensation. However, here we show that although H3S10 phosphorylation is indeed compromised in the H2Av null mutant, chromatin decondensation at heat shock loci is unaffected in the absence of JIL-1 as well as of H2Av and that there is no discernable decrease in the elongating form of RNA polymerase II in either mutant. Furthermore, mRNA for the major heat shock protein Hsp70 is transcribed at robust levels in both H2Av and JIL-1 null mutants. Using a different chromatin remodeling paradigm that is JIL-1 dependent, we provide evidence that ectopic tethering of JIL-1 and subsequent H3S10 phosphorylation recruits PARP-1 to the remodeling site independently of H2Av phosphorylation. These data strongly suggest that H2Av or H3S10 phosphorylation by JIL-1 is not required for chromatin decondensation or transcriptional elongation in Drosophila.
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Affiliation(s)
- Yeran Li
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Chao Wang
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Weili Cai
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Saheli Sengupta
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Michael Zavortink
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Huai Deng
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Jack Girton
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Jørgen Johansen
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Kristen M Johansen
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
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Hodjat M, Rahmani S, Khan F, Niaz K, Navaei–Nigjeh M, Mohammadi Nejad S, Abdollahi M. Environmental toxicants, incidence of degenerative diseases, and therapies from the epigenetic point of view. Arch Toxicol 2017; 91:2577-2597. [DOI: 10.1007/s00204-017-1979-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 05/04/2017] [Indexed: 01/12/2023]
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Sengupta S, Rath U, Yao C, Zavortink M, Wang C, Girton J, Johansen KM, Johansen J. Digitor/dASCIZ Has Multiple Roles in Drosophila Development. PLoS One 2016; 11:e0166829. [PMID: 27861562 PMCID: PMC5115829 DOI: 10.1371/journal.pone.0166829] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 11/05/2016] [Indexed: 12/02/2022] Open
Abstract
In this study we provide evidence that the spindle matrix protein Skeletor in Drosophila interacts with the human ASCIZ (also known as ATMIN and ZNF822) ortholog, Digitor/dASCIZ. This interaction was first detected in a yeast two-hybrid screen and subsequently confirmed by pull-down assays. We also confirm a previously documented function of Digitor/dASCIZ as a regulator of Dynein light chain/Cut up expression. Using transgenic expression of a mCitrine-labeled Digitor construct, we show that Digitor/dASCIZ is a nuclear protein that is localized to interband and developmental puff chromosomal regions during interphase but redistributes to the spindle region during mitosis. Its mitotic localization and physical interaction with Skeletor suggest the possibility that Digitor/dASCIZ plays a direct role in mitotic progression as a member of the spindle matrix complex. Furthermore, we have characterized a P-element insertion that is likely to be a true null Digitor/dASCIZ allele resulting in complete pupal lethality when homozygous, indicating that Digitor/dASCIZ is an essential gene. Phenotypic analysis of the mutant provided evidence that Digitor/dASCIZ plays critical roles in regulation of metamorphosis and organogenesis as well as in the DNA damage response. In the Digitor/dASCIZ null mutant larvae there was greatly elevated levels of γH2Av, indicating accumulation of DNA double-strand breaks. Furthermore, reduced levels of Digitor/dASCIZ decreased the resistance to paraquat-induced oxidative stress resulting in increased mortality in a stress test paradigm. We show that an early developmental consequence of the absence of Digitor/dASCIZ is reduced third instar larval brain size although overall larval development appeared otherwise normal at this stage. While Digitor/dASCIZ mutant larvae initiate pupation, all mutant pupae failed to eclose and exhibited various defects in metamorphosis such as impaired differentiation, incomplete disc eversion, and faulty apoptosis. Altogether we provide evidence that Digitor/dASCIZ is a nuclear protein that performs multiple roles in Drosophila larval and pupal development.
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Affiliation(s)
- Saheli Sengupta
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Uttama Rath
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Changfu Yao
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Michael Zavortink
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Chao Wang
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Jack Girton
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Kristen M. Johansen
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
- * E-mail: (JJ); (KMJ)
| | - Jørgen Johansen
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
- * E-mail: (JJ); (KMJ)
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Hong ST, Choi KW. Antagonistic roles of Drosophila Tctp and Brahma in chromatin remodelling and stabilizing repeated sequences. Nat Commun 2016; 7:12988. [PMID: 27687497 PMCID: PMC5056459 DOI: 10.1038/ncomms12988] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 08/24/2016] [Indexed: 12/30/2022] Open
Abstract
Genome stability is essential for all organisms. Translationally controlled tumour protein (TCTP) is a conserved protein associated with cancers. TCTP is involved in multiple intracellular functions, but its role in transcription and genome stability is poorly understood. Here, we demonstrate new functions of Drosophila TCTP (Tctp) in transcription and the stability of repeated sequences (rDNA and pericentromeric heterochromatin). Tctp binds Brahma (Brm) chromatin remodeler to negatively modulate its activity. Tctp mutants show abnormally high levels of transcription in a large set of genes and transposons. These defects are ameliorated by brm mutations. Furthermore, Tctp promotes the stability of repeated sequences by opposing the Brm function. Additional regulation of pericentromeric heterochromatin by Tctp is mediated by su(var)3-9 transcriptional regulation. Altogether, Tctp regulates transcription and the stability of repeated sequences by antagonizing excess Brm activity. This study provides insights into broader nuclear TCTP functions for the maintenance of genome stability. Genome stability is important for normal cellular function. Here, Hong and Choi show that translationally controlled tumour protein (TCTP) in Drosophila regulates pericentromeric chromatin remodelling and transcription via negatively regulating a chromatin remodeler Brahma.
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Affiliation(s)
- Sung-Tae Hong
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Korea
| | - Kwang-Wook Choi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Korea
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13
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Rodriguez P, Rojas J. cAMP-Induced Histones H3 Dephosphorylation Is Independent of PKA and MAP Kinase Activations and Correlates With mTOR Inactivation. J Cell Biochem 2015; 117:741-50. [PMID: 26335579 DOI: 10.1002/jcb.25359] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 09/01/2015] [Indexed: 01/28/2023]
Abstract
cAMP is a second messenger well documented to be involved in the phosphorylation of PKA, MAP kinase, and histone H3 (H3). Early, we reported that cAMP also induced H3 dephosphorylation in a variety of proliferating cell lines. Herein, it is shown that cAMP elicits a biphasic H3 dephosphorylation independent of PKA activation in cycling cells. H89, a potent inhibitor of PKA catalytic sub-unite, could not abolish this effect. Additionally, H89 induces a rapid and biphasic H3 serine 10 dephosphorylation, while a decline in the basal phosphorylation of CREB/ATF-1 is observed. Rp-cAMPS, an analog of cAMP and specific inhibitor of PKA, is unable to suppress cAMP-mediated H3 dephosphorylation, whereas Rp-cAMPS effectively blocks CREB/ATF-1 hyper-phosphorylation by cAMP and its inducers. Interestingly, cAMP exerts a rapid and profound H3 dephosphorylation at much lower concentration (50-fold lower, 0.125 mM) than the concentration required for maximal CREB/ATF-1 phosphorylation (5 mM). Much higher cAMP concentration is required to fully induce CREB/ATF-1 gain in phosphate (5 mM), which correlates with the inhibition of H3 dephosphorylation. Also, the dephosphorylation of H3 does not overlap at onset of MAP kinase phosphorylation pathways, p38 and ERK. Surprisingly, rapamycin (an mTOR inhibitor), cAMP, and its natural inducer isoproterenol, elicit identical dephosphorylation kinetics on both S6K1 ribosomal kinase (a downstream mTOR target) and H3. Finally, cAMP-induced H3 dephosphorylation is PP1/2-dependent. The results suggest that a pathway, requiring much lower cAMP concentration to that required for CREB/ATF-1 hyper-phosphorylation, is responsible for histone H3 dephosphorylation and may be linked to mTOR down regulation.
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Affiliation(s)
- Pedro Rodriguez
- Facultad de Ciencias M, é, dicas, Escuela de Medicina, Universidad de Santiago de Chile (USACH), el Belloto 3530, segundo piso. Avenida Libertador Bernardo O'Higgins n°3363, Estación Central, Santiago, Chile
| | - Juan Rojas
- Facultad de Ciencias M, é, dicas, Escuela de Medicina, Universidad de Santiago de Chile (USACH), el Belloto 3530, segundo piso. Avenida Libertador Bernardo O'Higgins n°3363, Estación Central, Santiago, Chile
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Zhang Q, Giebler HA, Isaacson MK, Nyborg JK. Eviction of linker histone H1 by NAP-family histone chaperones enhances activated transcription. Epigenetics Chromatin 2015; 8:30. [PMID: 26339295 PMCID: PMC4558729 DOI: 10.1186/s13072-015-0022-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 08/13/2015] [Indexed: 12/31/2022] Open
Abstract
Background In the Metazoan nucleus, core histones assemble the genomic DNA to form nucleosome arrays, which are further compacted into dense chromatin structures by the linker histone H1. The extraordinary density of chromatin creates an obstacle for accessing the genetic information. Regulation of chromatin dynamics is therefore critical to cellular homeostasis, and histone chaperones serve as prominent players in these processes. In the current study, we examined the role of specific histone chaperones in negotiating the inherently repressive chromatin structure during transcriptional activation. Results Using a model promoter, we demonstrate that the human nucleosome assembly protein family members hNap1 and SET/Taf1β stimulate transcription in vitro during pre-initiation complex formation, prior to elongation. This stimulatory effect is dependent upon the presence of activators, p300, and Acetyl-CoA. We show that transcription from our chromatin template is strongly repressed by H1, and that both histone chaperones enhance RNA synthesis by overcoming H1-induced repression. Importantly, both hNap1 and SET/Taf1β directly bind H1, and function to enhance transcription by evicting the linker histone from chromatin reconstituted with H1. In vivo studies demonstrate that SET/Taf1β, but not hNap1, strongly stimulates activated transcription from the chromosomally-integrated model promoter, consistent with the observation that SET/Taf1β is nuclear, whereas hNap1 is primarily cytoplasmic. Together, these observations indicate that SET/Taf1β may serve as a critical regulator of H1 dynamics and gene activation in vivo. Conclusions These studies uncover a novel function for SET that mechanistically couples transcriptional derepression with H1 dynamics. Furthermore, they underscore the significance of chaperone-dependent H1 displacement as an essential early step in the transition of a promoter from a dense chromatin state into one that is permissive to transcription factor binding and robust activation.
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Affiliation(s)
- Qian Zhang
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870 USA
| | - Holli A Giebler
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870 USA
| | - Marisa K Isaacson
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870 USA ; Pace University, 1 Pace Plaza, New York, NY 10038 USA
| | - Jennifer K Nyborg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870 USA
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Park CS, Valomon A, Welzl H. Integrative Transcriptome Profiling of Cognitive Aging and Its Preservation through Ser/Thr Protein Phosphatase Regulation. PLoS One 2015; 10:e0130891. [PMID: 26102285 PMCID: PMC4478024 DOI: 10.1371/journal.pone.0130891] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 05/26/2015] [Indexed: 01/28/2023] Open
Abstract
Environmental enrichment has been reported to delay or restore age-related cognitive deficits, however, a mechanism to account for the cause and progression of normal cognitive decline and its preservation by environmental enrichment is lacking. Using genome-wide SAGE-Seq, we provide a global assessment of differentially expressed genes altered with age and environmental enrichment in the hippocampus. Qualitative and quantitative proteomics in naïve young and aged mice was used to further identify phosphorylated proteins differentially expressed with age. We found that increased expression of endogenous protein phosphatase-1 inhibitors in aged mice may be characteristic of long-term environmental enrichment and improved cognitive status. As such, hippocampus-dependent performances in spatial, recognition, and associative memories, which are sensitive to aging, were preserved by environmental enrichment and accompanied by decreased protein phosphatase activity. Age-associated phosphorylated proteins were also found to correspond to the functional categories of age-associated genes identified through transcriptome analysis. Together, this study provides a comprehensive map of the transcriptome and proteome in the aging brain, and elucidates endogenous protein phosphatase-1 inhibition as a potential means through which environmental enrichment may ameliorate age-related cognitive deficits.
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Affiliation(s)
- C. Sehwan Park
- Brain Research Institute, Medical Faculty of the University of Zürich and Department of Health Science and Technology ETH Zürich, Zürich, Switzerland
| | - Amandine Valomon
- Brain Research Institute, Medical Faculty of the University of Zürich and Department of Health Science and Technology ETH Zürich, Zürich, Switzerland
- Institute of Pharmacology and Toxicology, Human Sleep Psychopharmacology, University of Zürich, Zürich, Switzerland
| | - Hans Welzl
- Institute of Anatomy, Neuroanatomy and Behavior, University of Zürich, Zürich, Switzerland
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16
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Chemical “Diversity” of Chromatin Through Histone Variants and Histone Modifications. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/s40610-015-0005-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Hu X, Lu X, Liu R, Ai N, Cao Z, Li Y, Liu J, Yu B, Liu K, Wang H, Zhou C, Wang Y, Han A, Ding F, Chen R. Histone cross-talk connects protein phosphatase 1α (PP1α) and histone deacetylase (HDAC) pathways to regulate the functional transition of bromodomain-containing 4 (BRD4) for inducible gene expression. J Biol Chem 2014; 289:23154-23167. [PMID: 24939842 PMCID: PMC4132813 DOI: 10.1074/jbc.m114.570812] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Transcription elongation has been recognized as a rate-limiting step for the expression of signal-inducible genes. Through recruitment of positive transcription elongation factor P-TEFb, the bromodomain-containing protein BRD4 plays critical roles in regulating the transcription elongation of a vast array of inducible genes that are important for multiple cellular processes. The diverse biological roles of BRD4 have been proposed to rely on its functional transition between chromatin targeting and transcription regulation. The signaling pathways and the molecular mechanism for regulating this transition process, however, are largely unknown. Here, we report a novel role of phosphorylated Ser(10) of histone H3 (H3S10ph) in governing the functional transition of BRD4. We identified that the acetylated lysines 5 and 8 of nucleosomal histone H4 (H4K5ac/K8ac) is the BRD4 binding site, and the protein phosphatase PP1α and class I histone deacetylase (HDAC1/2/3) signaling pathways are essential for the stress-induced BRD4 release from chromatin. In the unstressed state, phosphorylated H3S10 prevents the deacetylation of nucleosomal H4K5ac/K8ac by HDAC1/2/3, thereby locking up the majority of BRD4 onto chromatin. Upon stress, PP1α-mediated dephosphorylation of H3S10ph allows the deacetylation of nucleosomal H4K5ac/K8ac by HDAC1/2/3, thereby leading to the release of chromatin-bound BRD4 for subsequent recruitment of P-TEFb to enhance the expression of inducible genes. Therefore, our study revealed a novel mechanism that the histone cross-talk between H3S10ph and H4K5ac/K8ac connects PP1α and HDACs to govern the functional transition of BRD4. Combined with previous studies on the regulation of P-TEFb activation, the intricate signaling network for the tight control of transcription elongation is established.
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Affiliation(s)
- Xiangming Hu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Xiaodong Lu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Runzhong Liu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Nanping Ai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Zhenhua Cao
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Yannan Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Jiangfang Liu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Bin Yu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Kai Liu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Huiping Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Chao Zhou
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Yu Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Aidong Han
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Feng Ding
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China.
| | - Ruichuan Chen
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China.
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Mohan RD, Abmayr SM, Workman JL. The expanding role for chromatin and transcription in polyglutamine disease. Curr Opin Genet Dev 2014; 26:96-104. [PMID: 25108806 DOI: 10.1016/j.gde.2014.06.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 06/22/2014] [Accepted: 06/25/2014] [Indexed: 11/28/2022]
Abstract
Nine genetic diseases arise from expansion of CAG repeats in seemingly unrelated genes. They are referred to as polyglutamine (polyQ) diseases due to the presence of elongated glutamine tracts in the corresponding proteins. The pathologic consequences of polyQ expansion include progressive spinal, cerebellar, and neural degeneration. These pathologies are not identical, however, suggesting that disruption of protein-specific functions is crucial to establish and maintain each disease. A closer examination of protein function reveals that several act as regulators of gene expression. Here we examine the roles these proteins play in regulating gene expression, discuss how polyQ expansion may disrupt these functions to cause disease, and speculate on the neural specificity of perturbing ubiquitous gene regulators.
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Affiliation(s)
- Ryan D Mohan
- Stowers Institute for Medical Research, 1000 E 50th St., Kansas City, MO 64110, USA
| | - Susan M Abmayr
- Stowers Institute for Medical Research, 1000 E 50th St., Kansas City, MO 64110, USA.
| | - Jerry L Workman
- Stowers Institute for Medical Research, 1000 E 50th St., Kansas City, MO 64110, USA.
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19
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20
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Cha TL, Chuang MJ, Tang SH, Wu ST, Sun KH, Chen TT, Sun GH, Chang SY, Yu CP, Ho JY, Liu SY, Huang SM, Yu DS. Emodin modulates epigenetic modifications and suppresses bladder carcinoma cell growth. Mol Carcinog 2013; 54:167-77. [PMID: 24115089 DOI: 10.1002/mc.22084] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 07/19/2013] [Accepted: 08/07/2013] [Indexed: 11/09/2022]
Abstract
The deregulation of epigenetics was involved in early and subsequent carcinogenic events. Reversing cancer epigenetics to restore a normal epigenetic condition could be a rational approach for cancer treatment and specialized prevention. In the present study, we found that the expression levels of two epigenetic markers, histone H3K27 trimethylation (H3K27me3), was low but histone H3S10 phosphorylation (pH3Ser10) was high in human bladder cancer tissues, which showed opposite expression patterns in their normal counterparts. Thus, we investigated whether a natural product, emodin, has the ability to reverse these two epigenetic modifications and inhibit bladder cancer cell growth. Emodin significantly inhibited the cell growth of four bladder cancer cell lines in a dose- and time-dependent manner. Emodin treatment did not induce specific cell cycle arrest, but it altered epigenetic modifications. Emodin treatment resulted in the suppression of pH3Ser10 and increased H3K27me3, contributing to gene silencing in bladder cancer cells. Microarray analysis demonstrated that oncogenic genes including fatty acid binding protein 4 (FABP4) and fibroblast growth factor binding protein 1 (HBP17), RGS4, tissue inhibitor of metalloproteinase 3 (TIMP3), WNT5b, URB, and collagen, type VIII, alpha 1 (COL8A1) responsible for proliferation, survival, inflammation, and carcinogenesis were significantly repressed by emodin. The ChIP assays also showed that emodin increased H3K27me3 but decreased pH3Ser10 modifications on the promoters of repressed genes, which indicate that emodin reverses the cancer epigenetics towards normal epigenetic situations. In conclusion, our work demonstrates the significant anti-neoplastic activity of emodin on bladder cancer cells and elucidates the novel mechanisms of emodin-mediated epigenetic modulation of target genes. Our study warrants further investigation of emodin as an effective therapeutic or preventive agent for bladder cancer.
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Affiliation(s)
- Tai-Lung Cha
- Division of Urology, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC; Department of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan, ROC; Graduate Institutes of Life Sciences, National Defense Medical Center, Taipei, Taiwan, ROC; Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan, ROC
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Apostolidis SA, Rauen T, Hedrich CM, Tsokos GC, Crispín JC. Protein phosphatase 2A enables expression of interleukin 17 (IL-17) through chromatin remodeling. J Biol Chem 2013; 288:26775-84. [PMID: 23918926 DOI: 10.1074/jbc.m113.483743] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Protein phosphatase 2A (PP2A) is a heterotrimeric serine/threonine phosphatase involved in essential cellular functions. T cells from patients with systemic lupus erythematosus (SLE) express high levels of the catalytic subunit of PP2A (PP2Ac). A mouse overexpressing PP2Ac in T cells develops glomerulonephritis in an IL-17-dependent manner. Here, using microarray analyses, we demonstrate that increased expression of PP2Ac grants T cells the capacity to produce an array of proinflammatory effector molecules. Because IL-17 is important in the expression of glomerulonephritis, we studied the mechanism through which PP2Ac dysregulation facilitates its production. We report that PP2Ac is involved in the regulation of the Il17 locus by enhancing histone 3 acetylation through a mechanism that involves activation of interferon regulatory factor 4. Increased histone 3 acetylation of the Il17 locus is shared between T cells of PP2Ac transgenic mice and patients with SLE. We propose that, by promoting the inflammatory capacity of T cells, PP2Ac dysregulation contributes to the pathogenesis of SLE.
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Affiliation(s)
- Sokratis A Apostolidis
- From the Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215
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22
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Peptidylarginine deiminases in citrullination, gene regulation, health and pathogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2013; 1829:1126-35. [PMID: 23860259 DOI: 10.1016/j.bbagrm.2013.07.003] [Citation(s) in RCA: 225] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 07/03/2013] [Accepted: 07/08/2013] [Indexed: 01/17/2023]
Abstract
Peptidylarginine deiminases are a family of enzymes that mediate post-translational modifications of protein arginine residues by deimination or demethylimination to produce citrulline. In vitro, the activity of PADs is dependent on calcium and reductive reagents carrying a free sulfhydryl group. The discovery that PAD4 can target both arginine and methyl-arginine for citrullination about 10years ago renewed our interest in studying this family of enzymes in gene regulation and their physiological functions. The deregulation of PADs is involved in the etiology of multiple human diseases, including cancers and autoimmune disorders. There is a growing effort to develop isoform specific PAD inhibitors for disease treatment. However, the regulation of the activity of PADs in vivo remains largely elusive, and we expect that much will be learned about the role of these enzymes in a normal life cycle and under pathology conditions.
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Wang C, Yao C, Li Y, Cai W, Bao X, Girton J, Johansen J, Johansen KM. Evidence against a role for the JIL-1 kinase in H3S28 phosphorylation and 14-3-3 recruitment to active genes in Drosophila. PLoS One 2013; 8:e62484. [PMID: 23638096 PMCID: PMC3640051 DOI: 10.1371/journal.pone.0062484] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 03/21/2013] [Indexed: 01/19/2023] Open
Abstract
JIL-1 is the major kinase controlling phosphorylation of histone H3S10 and has been demonstrated to function to counteract heterochromatization and gene silencing. However, an alternative model has been proposed in which JIL-1 is required for transcription to occur, additionally phosphorylates H3S28, and recruits 14-3-3 to active genes. Since these findings are incompatible with our previous demonstration that there are robust levels of transcription in the complete absence of JIL-1 and that JIL-1 is not present at developmental or heat shock-induced polytene chromosome puffs, we have reexamined JIL-1’s possible role in H3S28 phosphorylation and 14-3-3 recruitment. Using two different H3S28ph antibodies we show by immunocytochemistry and immunoblotting that in Drosophila the H3S28ph mark is not present at detectable levels above background on polytene chromosomes at interphase but only on chromosomes at pro-, meta-, and anaphase during cell division in S2 cells and third instar larval neuroblasts. Moreover, this mitotic H3S28ph signal is also present in a JIL-1 null mutant background at undiminished levels suggesting that JIL-1 is not the mitotic H3S28ph kinase. We also demonstrate that H3S28ph is not enriched at heat shock puffs. Using two different pan-specific 14-3-3 antibodies as well as an enhancer trap 14-3-3ε-GFP line we show that 14-3-3, while present in salivary gland nuclei, does not localize to chromosomes but only to the nuclear matrix surrounding the chromosomes. In our hands 14-3-3 is not recruited to developmental or heat shock puffs. Furthermore, using a lacO repeat tethering system to target LacI-JIL-1 to ectopic sites on polytene chromosomes we show that only H3S10ph is present and upregulated at such sites, not H3S28ph or 14-3-3. Thus, our results argue strongly against a model where JIL-1 is required for H3S28 phosphorylation and 14-3-3 recruitment at active genes.
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Affiliation(s)
- Chao Wang
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Changfu Yao
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Yeran Li
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Weili Cai
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Xiaomin Bao
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Jack Girton
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
| | - Jørgen Johansen
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
- * E-mail: (KMJ); (JJ)
| | - Kristen M. Johansen
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America
- * E-mail: (KMJ); (JJ)
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Identification and characterization of proteins involved in nuclear organization using Drosophila GFP protein trap lines. PLoS One 2013; 8:e53091. [PMID: 23341925 PMCID: PMC3547006 DOI: 10.1371/journal.pone.0053091] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 11/23/2012] [Indexed: 12/22/2022] Open
Abstract
Background Strains from a collection of Drosophila GFP protein trap lines express GFP in the normal tissues where the endogenous protein is present. This collection can be used to screen for proteins distributed in the nucleus in a non-uniform pattern. Methodology/Principal Findings We analyzed four lines that show peripheral or punctate nuclear staining. One of these lines affects an uncharacterized gene named CG11138. The CG11138 protein shows a punctate distribution in the nuclear periphery similar to that of Drosophila insulator proteins but does not co-localize with known insulators. Interestingly, mutations in Lamin proteins result in alterations in CG11138 localization, suggesting that this protein may be a novel component of the nuclear lamina. A second line affects the Decondensation factor 31 (Df31) gene, which encodes a protein with a unique nuclear distribution that appears to segment the nucleus into four different compartments. The X-chromosome of males is confined to one of these compartments. We also find that Drosophila Nucleoplasmin (dNlp) is present in regions of active transcription. Heat shock leads to loss of dNlp from previously transcribed regions of polytene chromosome without redistribution to the heat shock genes. Analysis of Stonewall (Stwl), a protein previously found to be necessary for the maintenance of germline stem cells, shows that Stwl is present in a punctate pattern in the nucleus that partially overlaps with that of known insulator proteins. Finally we show that Stwl, dNlp, and Df31 form part of a highly interactive network. The properties of other components of this network may help understand the role of these proteins in nuclear biology. Conclusions/Significance These results establish screening of GFP protein trap alleles as a strategy to identify factors with novel cellular functions. Information gained from the analysis of CG11138 Stwl, dNlp, and Df31 sets the stage for future studies of these proteins.
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Abstract
Protein phosphatases of the type 2A family (PP2A) represent a major fraction of cellular Ser/Thr phosphatase activity in any given human tissue. In this review, we describe how the holoenzymic nature of PP2A and the existence of several distinct PP2A composing subunits allow for the generation of multiple structurally and functionally different PP2A complexes, explaining why PP2A is involved in the regulation of so many diverse cell biological and physiological processes. Moreover, in human disease, most notably in several cancers and Alzheimer's Disease, PP2A expression and/or activity have been found significantly decreased, underscoring its important functions as a major tumor suppressor and tau phosphatase. Hence, several recent preclinical studies have demonstrated that pharmacological restoration of PP2A activity, as well as pharmacological PP2A inhibition, under certain conditions, may be of significant future therapeutic value.
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Almeida LO, Goto RN, Pestana CR, Uyemura SA, Gutkind S, Curti C, Leopoldino AM. SET overexpression decreases cell detoxification efficiency: ALDH2 and GSTP1 are downregulated, DDR is impaired and DNA damage accumulates. FEBS J 2012; 279:4615-28. [PMID: 23106910 DOI: 10.1111/febs.12047] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 10/01/2012] [Accepted: 10/25/2012] [Indexed: 11/26/2022]
Abstract
Alcohol and tobacco consumption are risk factors for head and neck squamous cell carcinoma (HNSCC). Aldehyde dehydrogenase 2 (ALDH2) and glutathione S-transferase pi 1 (GSTP1) are important enzymes for cellular detoxification and low efficiencies are implicated in cancer. We assessed the potential role of SET protein overexpression, a histone acetylation modulator accumulated in HNSCC, in gene regulation and protein activity of ALDH2 and GSTP1. SET was knocked down in HN13, HN12 and Cal27, and overexpressed in HEK293 cells; ethanol and cisplatin were the chemical agents. Cells with SET overexpression (HEK293/SET, HN13 and HN12) showed lower ALDH2 and GSTP1 mRNA levels and trichostatin A increased them (real-time PCR). Ethanol upregulated GSTP1 and ALDH2 mRNAs, whereas cisplatin upregulated GSTP1 in HEK293 cells. SET-chromatin binding revealed SET interaction with ALDH2 and GSTP1 promoters, specifically via SET NAP domain; ethanol and cisplatin abolished SET binding. ALDH2 and GSTP1 efficiency was assessed by enzymatic and comet assay. A lower ALDH2 activity was associated with greater DNA damage (tail intensity) in HEK293/SET compared with HEK293 cells, whereas HN13/siSET showed ALDH2 activity higher than HN13 cells. HN13/siSET cells showed increased tail intensity. Cisplatin-induced DNA damage response showed negative relationship between SET overexpression and BRCA2 recruitment. SET downregulated repair genes ATM, BRCA1 and CHEK2 and upregulated TP53. Cisplatin-induced cell-cycle arrest occurred in G(0) /G(1) and S in HEK293 cells, whereas HEK293/SET showed G(2) /M stalling. Overall, cisplatin was more cytotoxic for HN13 than HN13/siSET cells. Our data suggest a role for SET in cellular detoxification, DNA damage response and genome integrity.
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Affiliation(s)
- Luciana O Almeida
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, 14040-903 Ribeirão Preto, SP, Brazil
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Smolle M, Workman JL. Transcription-associated histone modifications and cryptic transcription. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2012; 1829:84-97. [PMID: 22982198 DOI: 10.1016/j.bbagrm.2012.08.008] [Citation(s) in RCA: 151] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 08/14/2012] [Accepted: 08/29/2012] [Indexed: 12/21/2022]
Abstract
Eukaryotic genomes are packaged into chromatin, a highly organized structure consisting of DNA and histone proteins. All nuclear processes take place in the context of chromatin. Modifications of either DNA or histone proteins have fundamental effects on chromatin structure and function, and thus influence processes such as transcription, replication or recombination. In this review we highlight histone modifications specifically associated with gene transcription by RNA polymerase II and summarize their genomic distributions. Finally, we discuss how (mis-)regulation of these histone modifications perturbs chromatin organization over coding regions and results in the appearance of aberrant, intragenic transcription. This article is part of a Special Issue entitled: RNA polymerase II Transcript Elongation.
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Affiliation(s)
- Michaela Smolle
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
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Tadmouri A, Kiyonaka S, Barbado M, Rousset M, Fablet K, Sawamura S, Bahembera E, Pernet-Gallay K, Arnoult C, Miki T, Sadoul K, Gory-Faure S, Lambrecht C, Lesage F, Akiyama S, Khochbin S, Baulande S, Janssens V, Andrieux A, Dolmetsch R, Ronjat M, Mori Y, De Waard M. Cacnb4 directly couples electrical activity to gene expression, a process defective in juvenile epilepsy. EMBO J 2012; 31:3730-44. [PMID: 22892567 DOI: 10.1038/emboj.2012.226] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 07/17/2012] [Indexed: 12/11/2022] Open
Abstract
Calcium current through voltage-gated calcium channels (VGCC) controls gene expression. Here, we describe a novel signalling pathway in which the VGCC Cacnb4 subunit directly couples neuronal excitability to transcription. Electrical activity induces Cacnb4 association to Ppp2r5d, a regulatory subunit of PP2A phosphatase, followed by (i) nuclear translocation of Cacnb4/Ppp2r5d/PP2A, (ii) association with the tyrosine hydroxylase (TH) gene promoter through the nuclear transcription factor thyroid hormone receptor alpha (TRα), and (iii) histone binding through association of Cacnb4 with HP1γ concomitantly with Ser(10) histone H3 dephosphorylation by PP2A. This signalling cascade leads to TH gene repression by Cacnb4 and is controlled by the state of interaction between the SH3 and guanylate kinase (GK) modules of Cacnb4. The human R482X CACNB4 mutation, responsible for a form of juvenile myoclonic epilepsy, prevents association with Ppp2r5 and nuclear targeting of the complex by altering Cacnb4 conformation. These findings demonstrate that an intact VGCC subunit acts as a repressor recruiting platform to control neuronal gene expression.
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Affiliation(s)
- Abir Tadmouri
- Unité Inserm U, Grenoble Institute of Neuroscience, Université Joseph Fourier, La Tronche, France
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The BEAF insulator regulates genes involved in cell polarity and neoplastic growth. Dev Biol 2012; 369:124-32. [PMID: 22743648 DOI: 10.1016/j.ydbio.2012.06.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/01/2012] [Accepted: 06/20/2012] [Indexed: 01/05/2023]
Abstract
Boundary Element Associated Factor-32 (BEAF-32) is an insulator protein predominantly found near gene promoters and thought to play a role in gene expression. We find that mutations in BEAF-32 are lethal, show loss of epithelial morphology in imaginal discs and cause neoplastic growth defects. To investigate the molecular mechanisms underlying this phenotype, we carried out a genome-wide analysis of BEAF-32 localization in wing imaginal disc cells. Mutation of BEAF-32 results in miss-regulation of 3850 genes by at least 1.5-fold, 794 of which are bound by this protein in wing imaginal cells. Up-regulated genes encode proteins involved in cell polarity, cell proliferation and cell differentiation. Among the down-regulated genes are those encoding components of the wingless pathway, which is required for cell differentiation. Miss-regulation of these genes explains the unregulated cell growth and neoplastic phenotypes observed in imaginal tissues of BEAF-32 mutants.
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Kellner WA, Ramos E, Van Bortle K, Takenaka N, Corces VG. Genome-wide phosphoacetylation of histone H3 at Drosophila enhancers and promoters. Genome Res 2012; 22:1081-8. [PMID: 22508764 PMCID: PMC3371715 DOI: 10.1101/gr.136929.111] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Transcription regulation is mediated by enhancers that bind sequence-specific transcription factors, which in turn interact with the promoters of the genes they control. Here, we show that the JIL-1 kinase is present at both enhancers and promoters of ecdysone-induced Drosophila genes, where it phosphorylates the Ser10 and Ser28 residues of histone H3. JIL-1 is also required for CREB binding protein (CBP)-mediated acetylation of Lys27, a well-characterized mark of active enhancers. The presence of these proteins at enhancers and promoters of ecdysone-induced genes results in the establishment of the H3K9acS10ph and H3K27acS28ph marks at both regulatory sequences. These modifications are necessary for the recruitment of 14-3-3, a scaffolding protein capable of facilitating interactions between two simultaneously bound proteins. Chromatin conformation capture assays indicate that interaction between the enhancer and the promoter is dependent on the presence of JIL-1, 14-3-3, and CBP. Genome-wide analyses extend these conclusions to most Drosophila genes, showing that the presence of JIL-1, H3K9acS10ph, and H3K27acS28ph is a general feature of enhancers and promoters in this organism.
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Affiliation(s)
- Wendy A Kellner
- Department of Biology, Emory University, Atlanta, Georgia 30322, USA
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Nowak SJ, Aihara H, Gonzalez K, Nibu Y, Baylies MK. Akirin links twist-regulated transcription with the Brahma chromatin remodeling complex during embryogenesis. PLoS Genet 2012; 8:e1002547. [PMID: 22396663 PMCID: PMC3291577 DOI: 10.1371/journal.pgen.1002547] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 01/04/2012] [Indexed: 11/19/2022] Open
Abstract
The activities of developmentally critical transcription factors are regulated via interactions with cofactors. Such interactions influence transcription factor activity either directly through protein–protein interactions or indirectly by altering the local chromatin environment. Using a yeast double-interaction screen, we identified a highly conserved nuclear protein, Akirin, as a novel cofactor of the key Drosophila melanogaster mesoderm and muscle transcription factor Twist. We find that Akirin interacts genetically and physically with Twist to facilitate expression of some, but not all, Twist-regulated genes during embryonic myogenesis. akirin mutant embryos have muscle defects consistent with altered regulation of a subset of Twist-regulated genes. To regulate transcription, Akirin colocalizes and genetically interacts with subunits of the Brahma SWI/SNF-class chromatin remodeling complex. Our results suggest that, mechanistically, Akirin mediates a novel connection between Twist and a chromatin remodeling complex to facilitate changes in the chromatin environment, leading to the optimal expression of some Twist-regulated genes during Drosophila myogenesis. We propose that this Akirin-mediated link between transcription factors and the Brahma complex represents a novel paradigm for providing tissue and target specificity for transcription factor interactions with the chromatin remodeling machinery. The proper development of the diverse array of cell types in an organism depends upon the induction and repression of specific genes at particular times and places. This gene regulation requires both the activity of tissue-specific transcriptional regulators and the modulation of the chromatin environment. To date, a complete picture of the interplay between these two processes remains unclear. To address this, we examined the activity of the evolutionarily conserved transcription factor Twist during embryogenesis of Drosophila melanogaster. While Twist has multiple activities and roles during development, a direct link between Twist and chromatin remodeling is unknown. We identified a highly conserved protein, Akirin, as a link between Twist and chromatin remodeling factors. Akirin is required for optimal expression of a Twist-dependent target during muscle development via interactions with the Drosophila SWI/SNF chromatin remodeling complex. Interestingly, Akirin is not required for activation of all Twist-dependent enhancers, suggesting that Akirin refines Twist activity outputs and that different Twist-dependent targets have different requirements for chromatin remodeling during development. Our data further suggests that Akirin similarly links the SWI/SNF chromatin remodeling complex with other transcription factors during development. This work has important ramifications for understanding both normal development and diseases such as cancer.
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Affiliation(s)
- Scott J. Nowak
- Program in Developmental Biology, Sloan Kettering Institute, New York, New York, United States of America
| | - Hitoshi Aihara
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, United States of America
| | - Katie Gonzalez
- Weill Cornell Graduate School of Biomedical Sciences, Cornell University, New York, New York, United States of America
| | - Yutaka Nibu
- Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, United States of America
- Weill Cornell Graduate School of Biomedical Sciences, Cornell University, New York, New York, United States of America
| | - Mary K. Baylies
- Program in Developmental Biology, Sloan Kettering Institute, New York, New York, United States of America
- Weill Cornell Graduate School of Biomedical Sciences, Cornell University, New York, New York, United States of America
- * E-mail:
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Bíró J, Farkas I, Domoki M, Otvös K, Bottka S, Dombrádi V, Fehér A. The histone phosphatase inhibitory property of plant nucleosome assembly protein-related proteins (NRPs). PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2012; 52:162-168. [PMID: 22285370 DOI: 10.1016/j.plaphy.2011.12.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 12/31/2011] [Indexed: 05/31/2023]
Abstract
SET/I(2)(PP2A), a member of the family of nucleosome assembly proteins (NAPs), has been previously described as a multifunctional protein inhibiting protein phosphatase 2A (PP2A)-mediated histone H3((pSer10)) dephosphorylation during the heat shock response in animal cells. In the present work we demonstrate that its plant orthologs, designated as NAP-related proteins (NRPs), have a similar in vitro biochemical activity and interact with PP2A and histone H3((pSer10))in vivo. Although heat shock gene promoters were found to be associated with histone H3((pSer10))-marked chromatin following a high temperature treatment, heat shock gene expression was not affected in NRP-deficient mutant Arabidopsis thaliana (L.) plantlets. These observations indicate that NRPs are potential regulators of histone dephosphorylation in plants, but they are dispensable for gene expression reorganization in response to heat shock.
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Affiliation(s)
- Judit Bíró
- Institute of Plant Biology, Biological Research Center, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary
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Methods for analyzing histone citrullination in chromatin structure and gene regulation. Methods Mol Biol 2012; 809:473-88. [PMID: 22113295 DOI: 10.1007/978-1-61779-376-9_31] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Histone posttranslational modifications play significant roles in regulating chromatin structure and gene expression. One of the histone modifications, histone citrullination, is catalyzed by an enzyme called peptidylarginine deiminase 4 (PAD4, also called PADI4), which converts both histone arginine (Arg) and mono-methyl arginine residues to citrulline. Recent studies have found that histone citrullination counteracts the effect of histone arginine methylation and functions as a repressive marker to turn off gene expression. Here, we describe assays to study histone citrullination by PAD4 in vitro and in vivo. We also describe approaches to measure histone citrullination levels at gene promoters using chromatin immunoprecipitation assay and analyze the effects of PAD4 inhibitor on cell cycle and apoptosis by flow cytometry. These methods would be useful techniques to study this unique histone modification.
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The chromodomain-containing NH(2)-terminus of Chromator interacts with histone H1 and is required for correct targeting to chromatin. Chromosoma 2011; 121:209-20. [PMID: 22203189 DOI: 10.1007/s00412-011-0355-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 11/22/2011] [Accepted: 12/09/2011] [Indexed: 01/13/2023]
Abstract
The chromodomain protein, Chromator, can be divided into two main domains, a NH(2)-terminal domain (NTD) containing the chromodomain (ChD) and a COOH-terminal domain (CTD) containing a nuclear localization signal. During interphase Chromator is localized to chromosomes; however, during cell division Chromator redistributes to form a macro molecular spindle matrix complex together with other nuclear proteins that contribute to microtubule spindle dynamics and proper chromosome segregation during mitosis. It has previously been demonstrated that the CTD is sufficient for targeting Chromator to the spindle matrix. In this study, we show that the NTD domain of Chromator is required for proper localization to chromatin during interphase and that chromosome morphology defects observed in Chromator hypomorphic mutant backgrounds can be largely rescued by expression of this domain. Furthermore, we show that the ChD domain can interact with histone H1 and that this interaction is necessary for correct chromatin targeting. Nonetheless, that localization to chromatin still occurs in the absence of the ChD indicates that Chromator possesses a second mechanism for chromatin association and we provide evidence that this association is mediated by other sequences residing in the NTD. Taken together these findings suggest that Chromator's chromatin functions are largely governed by the NH(2)-terminal domain whereas functions related to mitosis are mediated mainly by COOH-terminal sequences.
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Montes de Oca R, Andreassen PR, Wilson KL. Barrier-to-Autointegration Factor influences specific histone modifications. Nucleus 2011; 2:580-90. [PMID: 22127260 DOI: 10.4161/nucl.2.6.17960] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Defects in the nuclear envelope or nuclear 'lamina' networks cause disease and can perturb histone posttranslational (epigenetic) regulation. Barrier-to-Autointegration Factor (BAF) is an essential but enigmatic lamina component that binds lamins, LEM-domain proteins, DNA and histone H3 directly. We report that BAF copurified with nuclease-digested mononucleosomes and associated with modified histones in vivo. BAF overexpression significantly reduced global histone H3 acetylation by 18%. In cells that stably overexpressed BAF 3-fold, silencing mark H3-K27-Me1/3 and active marks H4-K16-Ac and H4-Ac5 decreased significantly. Significant increases were also seen for silencing mark H3-K9-Me3, active marks H3-K4-Me2, H3-K9/K14-Ac and H4-K5-Ac and a mark (H3-K79-Me2) associated with both active and silent chromatin. Other increases (H3-S10-P, H3-S28-P and silencing mark H3-K9-Me2) did not reach statistical significance. BAF overexpression also significantly influenced cell cycle distribution. Moreover, BAF associated in vivo with SET/I2PP2A (protein phosphatase 2A inhibitor; blocks H3 dephosphorylation) and G9a (H3-K9 methyltransferase), but showed no detectable association with HDAC1 or HATs. These findings reveal BAF as a novel epigenetic regulator and are discussed in relation to BAF deficiency phenotypes, which include a hereditary progeria syndrome and loss of pluripotency in embryonic stem cells.
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Affiliation(s)
- Rocío Montes de Oca
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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36
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Abstract
Post-translational modifications of histone proteins in conjunction with DNA methylation represent important events in the regulation of local and global genome functions. Advances in the study of these chromatin modifications established temporal and spatial co-localization of several distinct 'marks' on the same histone and/or the same nucleosome. Such complex modification patterns suggest the possibility of combinatorial effects. This idea was originally proposed to establish a code of histone modifications that regulates the interpretation of the genetic code of DNA. Indeed, interdependency of different modifications is now well documented in the literature. Our current understanding is that the function of a given histone modification is influenced by neighbouring or additional modifications. Such context sensitivity of the readout of a modification provides more flexible translation than would be possible if distinct modifications function as isolated units. The mechanistic principles for modification cross-talk can originate in the modulation of the activity of histone-modifying enzymes or may be due to selective recognition of these marks via modification of specific binding proteins. In the present chapter, we discuss fundamental biochemical principles of modification cross-talk and reflect on the interplay of chromatin marks in cellular signalling, cell-cycle progression and cell-fate determination.
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Shimada M, Haruta M, Niida H, Sawamoto K, Nakanishi M. Protein phosphatase 1γ is responsible for dephosphorylation of histone H3 at Thr 11 after DNA damage. EMBO Rep 2010; 11:883-9. [PMID: 20948546 DOI: 10.1038/embor.2010.152] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 08/31/2010] [Accepted: 08/31/2010] [Indexed: 01/03/2023] Open
Abstract
The DNA-damage-induced transcriptional suppression of cell cycle regulatory genes correlates with a reduction in histone H3-Thr 11 phosphorylation (H3-pThr 11) on their promoters that is partly mediated by the dissociation of Chk1 from chromatin. In this study, we identify protein phosphatase 1γ (PP1γ) as a phosphatase responsible for DNA-damage-induced H3-pThr 11 dephosphorylation. PP1γ is activated after DNA damage, which is mainly mediated by a reduction in Cdk-dependent phosphorylation of PP1γ at Thr 311. The depletion of PP1γ sensitizes HCT116 cells to DNA damage. Our results suggest that the ataxia telangiectasia, mutated and Rad3-related-Chk1 axis regulates H3-pThr 11 dephosphorylation on DNA damage, at least in part by the activation of PP1γ through Chk1-dependent inhibition of Cdks.
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Affiliation(s)
- Midori Shimada
- Department of Cell Biology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
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38
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Simboeck E, Sawicka A, Zupkovitz G, Senese S, Winter S, Dequiedt F, Ogris E, Di Croce L, Chiocca S, Seiser C. A phosphorylation switch regulates the transcriptional activation of cell cycle regulator p21 by histone deacetylase inhibitors. J Biol Chem 2010; 285:41062-73. [PMID: 20952396 DOI: 10.1074/jbc.m110.184481] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Histone deacetylase inhibitors induce cell cycle arrest and apoptosis in tumor cells and are, therefore, promising anti-cancer drugs. The cyclin-dependent kinase inhibitor p21 is activated in histone deacetylase (HDAC) inhibitor-treated tumor cells, and its growth-inhibitory function contributes to the anti-tumorigenic effect of HDAC inhibitors. We show here that induction of p21 by trichostatin A involves MAP kinase signaling. Activation of the MAP kinase signaling pathway by growth factors or stress signals results in histone H3 serine 10 phosphorylation at the p21 promoter and is crucial for acetylation of the neighboring lysine 14 and recruitment of activated RNA polymerase II in response to trichostatin A treatment. In non-induced cells, the protein phosphatase PP2A is associated with the p21 gene and counteracts its activation. Induction of p21 is linked to simultaneous acetylation and phosphorylation of histone H3. The dual modification mark H3S10phK14ac at the activated p21 promoter is recognized by the phospho-binding protein 14-3-3ζ, which protects the phosphoacetylation mark from being processed by PP2A. Taken together we have revealed a cross-talk of reversible phosphorylation and acetylation signals that controls the activation of p21 by HDAC inhibitors and identify the phosphatase PP2A as chromatin-associated transcriptional repressor in mammalian cells.
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Affiliation(s)
- Elisabeth Simboeck
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter, A-1030 Vienna, Austria
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Beck IME, Vanden Berghe W, Vermeulen L, Yamamoto KR, Haegeman G, De Bosscher K. Crosstalk in inflammation: the interplay of glucocorticoid receptor-based mechanisms and kinases and phosphatases. Endocr Rev 2009; 30:830-82. [PMID: 19890091 PMCID: PMC2818158 DOI: 10.1210/er.2009-0013] [Citation(s) in RCA: 214] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 08/18/2009] [Indexed: 12/20/2022]
Abstract
Glucocorticoids (GCs) are steroidal ligands for the GC receptor (GR), which can function as a ligand-activated transcription factor. These steroidal ligands and derivatives thereof are the first line of treatment in a vast array of inflammatory diseases. However, due to the general surge of side effects associated with long-term use of GCs and the potential problem of GC resistance in some patients, the scientific world continues to search for a better understanding of the GC-mediated antiinflammatory mechanisms. The reversible phosphomodification of various mediators in the inflammatory process plays a key role in modulating and fine-tuning the sensitivity, longevity, and intensity of the inflammatory response. As such, the antiinflammatory GCs can modulate the activity and/or expression of various kinases and phosphatases, thus affecting the signaling efficacy toward the propagation of proinflammatory gene expression and proinflammatory gene mRNA stability. Conversely, phosphorylation of GR can affect GR ligand- and DNA-binding affinity, mobility, and cofactor recruitment, culminating in altered transactivation and transrepression capabilities of GR, and consequently leading to a modified antiinflammatory potential. Recently, new roles for kinases and phosphatases have been described in GR-based antiinflammatory mechanisms. Moreover, kinase inhibitors have become increasingly important as antiinflammatory tools, not only for research but also for therapeutic purposes. In light of these developments, we aim to illuminate the integrated interplay between GR signaling and its correlating kinases and phosphatases in the context of the clinically important combat of inflammation, giving attention to implications on GC-mediated side effects and therapy resistance.
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Affiliation(s)
- Ilse M E Beck
- Laboratory of Eukaryotic Gene Expression and Signal Transduction, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium
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40
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Xu S, Powers MA. Nuclear pore proteins and cancer. Semin Cell Dev Biol 2009; 20:620-30. [PMID: 19577736 PMCID: PMC2706781 DOI: 10.1016/j.semcdb.2009.03.003] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 03/05/2009] [Accepted: 03/09/2009] [Indexed: 12/28/2022]
Abstract
Nucleocytoplasmic trafficking of macromolecules, a highly specific and tightly regulated process, occurs exclusively through the nuclear pore complex. This immense structure is assembled from approximately 30 proteins, termed nucleoporins. Here we discuss the four nucleoporins that have been linked to cancers, either through elevated expression in tumors (Nup88) or through involvement in chromosomal translocations that encode chimeric fusion proteins (Tpr, Nup98, Nup214). In each case we consider the normal function of the nucleoporin and its translocation partners, as well as what is known about their mechanistic contributions to carcinogenesis, particularly in leukemias. Studies of nucleoporin-linked cancers have revealed novel mechanisms of oncogenesis and in the future, should continue to expand our understanding of cancer biology.
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Affiliation(s)
- Songli Xu
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | - Maureen A. Powers
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
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41
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Kabra DG, Gupta J, Tikoo K. Insulin induced alteration in post-translational modifications of histone H3 under a hyperglycemic condition in L6 skeletal muscle myoblasts. Biochim Biophys Acta Mol Basis Dis 2009; 1792:574-83. [PMID: 19327396 DOI: 10.1016/j.bbadis.2009.03.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2009] [Revised: 03/08/2009] [Accepted: 03/10/2009] [Indexed: 01/18/2023]
Abstract
Chromatin remodelling events, especially histone modifications are proposed to form the mainstay for most of the biological processes. However, the role of these histone modifications in the progression of diabetes is still unknown. Hyperglycemia plays a major role in diabetes and its complications. The present study was undertaken to check the effect of insulin on alterations in post-translational modifications of histone H3 in L6 myoblasts under a hyperglycemic condition. We provide first evidence that insulin under hyperglycemic condition alters multiple histone modifications by enhanced production of reactive oxygen species. Insulin induces dose dependent changes in Lysine 4 and 9 methylation, Ser 10 phosphorylation and acetylation of histone H3. Interestingly, insulin induced generation of reactive oxygen species induces dephosphorylation and deacetylation of histone H3. Preincubation with catalase and DPI prevents these changes in post-translational modifications of histone H3. Furthermore, changes in histone H3 phosphorylation was found to be independent of ERK, p38, RSK2 and MSK1. Moreover, serine/threonine phosphatase inhibitor, okadaic acid attenuates insulin induced dephosphorylation and deacetylation of histone H3, suggesting a role of serine/threonine phosphatases in altering modifications of histone H3. These changes in epigenetic modifications can provide new insights into pathogenesis of diabetes.
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Affiliation(s)
- Dhiraj G Kabra
- Laboratory of Chromatin Biology, Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar - 160 062 (Punjab), India
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42
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Barbado M, Fablet K, Ronjat M, De Waard M. Gene regulation by voltage-dependent calcium channels. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1793:1096-104. [PMID: 19250948 DOI: 10.1016/j.bbamcr.2009.02.004] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Revised: 02/13/2009] [Accepted: 02/16/2009] [Indexed: 12/11/2022]
Abstract
Ca2+ is the most widely used second messenger in cell biology and fulfills a plethora of essential cell functions. One of the most exciting findings of the last decades was the involvement of Ca2+ in the regulation of long-term cell adaptation through its ability to control gene expression. This finding provided a link between cell excitation and gene expression. In this review, we chose to focus on the role of voltage-dependent calcium channels in mediating gene expression in response to membrane depolarization. We illustrate the different pathways by which these channels are involved in excitation-transcription coupling, including the most recent Ca2+ ion-independent strategies that highlight the transcription factor role of calcium channels.
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Affiliation(s)
- Maud Barbado
- Grenoble Institute of Neuroscience, Inserm U 836-Team 3 Calcium Channels, Functions and Pathologies, Bâtiment Edmond Safra, Université Joseph Fourier, Site santé de la Tronche, BP 170, 38042 Grenoble cedex 9, France
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43
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Pagès G. MAP kinase phosphatase-1: a link between cell signaling and histone phosphorylation. Focus on “Histone H3 as a novel substrate for MAP kinase phosphatase-1”. Am J Physiol Cell Physiol 2009; 296:C233-4. [DOI: 10.1152/ajpcell.00637.2008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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44
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Brami-Cherrier K, Roze E, Girault JA, Betuing S, Caboche J. Role of the ERK/MSK1 signalling pathway in chromatin remodelling and brain responses to drugs of abuse. J Neurochem 2009; 108:1323-35. [PMID: 19183268 DOI: 10.1111/j.1471-4159.2009.05879.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Drugs of abuse induce neuroadaptations through regulation of gene expression. Although much attention has focused on transcription factor activities, new concepts have recently emerged on the role of chromatin remodelling as a prerequisite for regulation of gene expression in neurons. Thus, for transcription to occur, chromatin must be decondensed, a dynamic process that depends on post-translational modifications of histones. We review here these modifications with a particular emphasis on the role of histone H3 phosphorylation at the promoter of specific genes, including c-fos and c-jun. We trace the signalling pathways involved in H3 phosphorylation and provide evidence for a role of mitogen and stress-activated protein kinase-1 (MSK1) downstream from the MAPK/extracellular-signal regulated kinase (ERK) cascade. In response to cocaine, MSK1 controls an early phase of histone H3 phosphorylation at the c-fos promoter in striatal neurons. MSK1 action may be potentiated by the concomitant inhibition of protein phosphatase 1 by nuclear translocation of dopamine- and cAMP-regulated phosphoprotein Mr = 32 000. H3 phosphorylation by MSK1 is critically involved in c-fos transcription, and cocaine-induced locomotor sensitization. Thus, ERK plays a dual role in gene regulation and drug addiction by direct activation of transcription factors and by chromatin remodelling.
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Affiliation(s)
- Karen Brami-Cherrier
- UMR 7102, CNRS, Laboratoire de Neurobiologie des Processus Adaptatifs, [corrected] Université Pierre et Marie Curie-Paris-6, Paris, France
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45
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Plata MP, Kang HJ, Zhang S, Kuruganti S, Hsu SJ, Labrador M. Changes in chromatin structure correlate with transcriptional activity of nucleolar rDNA in polytene chromosomes. Chromosoma 2008; 118:303-22. [PMID: 19066928 DOI: 10.1007/s00412-008-0198-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 11/14/2008] [Accepted: 11/19/2008] [Indexed: 12/30/2022]
Abstract
Ribosomal DNA genes (rDNA) are found in tandem arrays of hundreds of repeated genes, but only a fraction of these genes are actively transcribed. The regulatory mechanism controlling the transition between active and inactive rDNA in higher eukaryotes is vital for cell survival. Here, we show that the nucleolus from Drosophila salivary gland cells contains two levels of chromatin organization reflecting differences in transcriptional activity: Decondensed chromatin is highly occupied with TATA-box-binding protein (TBP), phosphorylated H3S10, and acetylated H3K14, suggesting that rDNA in decondensed nucleolar areas is actively transcribed. Condensed chromatin lacks TBP, phosphorylated H3S10, or acetylated H3K14 and is enriched in the rDNA retrotransposons R1 and R2. The data show that R1 and R2 retrotransposons are not actively transcribed in salivary glands and may lead to the epigenetic silencing of flanking rDNA genes and that the silencing mechanisms of these sequences might be partially independent of heterochromatin formation by methylation of histone H3 at lysine 9 and binding of heterochromatin protein 1.
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Affiliation(s)
- Maria Piedad Plata
- Department of Biochemistry, Cellular and Molecular Biology, M407 Walters Life Sciences, The University of Tennessee, 1414 Cumberland Avenue, Knoxville, TN 37996, USA
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46
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Kinney CM, Chandrasekharan UM, Yang L, Shen J, Kinter M, McDermott MS, DiCorleto PE. Histone H3 as a novel substrate for MAP kinase phosphatase-1. Am J Physiol Cell Physiol 2008; 296:C242-9. [PMID: 19020052 DOI: 10.1152/ajpcell.00492.2008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Mitogen-activated protein (MAP) kinase phosphatase-1 (MKP-1) is a nuclear, dual-specificity phosphatase that has been shown to dephosphorylate MAP kinases. We used a "substrate-trap" technique involving a mutation in MKP-1 of the catalytically critical cysteine to a serine residue ("CS" mutant) to capture novel MKP-1 substrates. We transfected the MKP-1 (CS) mutant and control (wild-type, WT) constructs into phorbol 12-myristate 13-acetate (PMA)-activated COS-1 cells. MKP-1-substrate complexes were immunoprecipitated, which yielded four bands of 17, 15, 14, and 10 kDa with the CS MKP-1 mutant but not the WT MKP-1. The bands were identified by mass spectrometry as histones H3, H2B, H2A, and H4, respectively. Histone H3 was phosphorylated, and purified MKP-1 dephosphorylated histone H3 (phospho-Ser-10) in vitro; whereas, histone H3 (phospho-Thr-3) was unaffected. We have previously shown that thrombin and vascular endothelial growth factor (VEGF) upregulated MKP-1 in human endothelial cells (EC). We now show that both thrombin and VEGF caused dephosphorylation of histone H3 (phospho-Ser-10) and histone H3 (phospho-Thr-3) in EC with kinetics consistent with MKP-1 induction. Furthermore, MKP-1-specific small interfering RNA (siRNA) prevented VEGF- and thrombin-induced H3 (phospho-Ser-10) dephosphorylation but had no effect on H3 (phospho-Thr-3 or Thr-11) dephosphorylation. In summary, histone H3 is a novel substrate of MKP-1, and VEGF- and thrombin-induced H3 (phospho-Ser-10) dephosphorylation requires MKP-1. We propose that MKP-1-mediated H3 (phospho-Ser-10) dephosphorylation is a key regulatory step in EC activation by VEGF and thrombin.
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Affiliation(s)
- Corttrell M Kinney
- Dept. of Cell Biology, Lerner Research Institute and Cleveland Clinic Lerner College of Medicine of Case Western Reserve Univ., Cleveland Clinic, NB-21, 9500 Euclid Ave., Cleveland, OH 44195, USA
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Zheng YG, Wu J, Chen Z, Goodman M. Chemical regulation of epigenetic modifications: opportunities for new cancer therapy. Med Res Rev 2008; 28:645-87. [PMID: 18271058 DOI: 10.1002/med.20120] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Epigenetics is concerned about heritable changes in gene expression without alteration of the coding sequence. Epigenetic modification of chromatin includes methylation of genomic DNA as well as post-translational modification of chromatin-associated proteins, in particular, histones. The spectrum of histone and non-histone modifications ranges from the addition of relatively small groups such as methyl, acetyl and phosphoryl groups to the attachment of larger moieties such as poly(ADP-ribose) and small proteins ubiquitin or small ubiquitin-like modifier (SUMO). The combinatorial nature of DNA methylation and histone modifications constitutes a significant pathway of epigenetic regulation and considerably extends the information potential of the genetic code. Chromatin modification has emerged as a new fundamental mechanism for gene transcriptional activity control associated with many cellular processes like proliferation, growth, and differentiation. Also it is increasingly recognized that epigenetic modifications constitute important regulatory mechanisms for the pathogenesis of malignant transformations. We review here the recent progress in the development of chemical inhibitors/activators that target different chromatin modifying enzymes. Such potent natural or synthetic modulators can be utilized to establish the quantitative contributions of epigenetic modifications in DNA regulated pathways including transcription, replication, recombination and repair, as well as provide leads for developing new cancer therapeutics.
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Affiliation(s)
- Yujun George Zheng
- Department of Chemistry, Georgia State University, PO Box 4098, Atlanta, Georgia 30302-4098, USA.
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Cai W, Bao X, Deng H, Jin Y, Girton J, Johansen J, Johansen KM. RNA polymerase II-mediated transcription at active loci does not require histone H3S10 phosphorylation in Drosophila. Development 2008; 135:2917-25. [PMID: 18667461 PMCID: PMC2586995 DOI: 10.1242/dev.024927] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
JIL-1 is the major kinase controlling the phosphorylation state of histone H3S10 at interphase in Drosophila. In this study, we used three different commercially available histone H3S10 phosphorylation antibodies, as well as an acid-free polytene chromosome squash protocol that preserves the antigenicity of the histone H3S10 phospho-epitope, to examine the role of histone H3S10 phosphorylation in transcription under both heat shock and non-heat shock conditions. We show that there is no redistribution or upregulation of JIL-1 or histone H3S10 phosphorylation at transcriptionally active puffs in such polytene squash preparations after heat shock treatment. Furthermore, we provide evidence that heat shock-induced puffs in JIL-1 null mutant backgrounds are strongly labeled by antibody to the elongating form of RNA polymerase II (Pol IIoser2), indicating that Pol IIoser2 is actively involved in heat shock-induced transcription in the absence of histone H3S10 phosphorylation. This is supported by the finding that there is no change in the levels of Pol IIoser2 in JIL-1 null mutant backgrounds compared with wild type. mRNA from the six genes that encode the major heat shock protein in Drosophila, Hsp70, is transcribed at robust levels in JIL-1 null mutants, as directly demonstrated by qRT-PCR. Taken together, these data are inconsistent with the model that Pol II-dependent transcription at active loci requires JIL-1-mediated histone H3S10 phosphorylation, and instead support a model in which transcriptional defects in the absence of histone H3S10 phosphorylation are a result of structural alterations of chromatin.
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Affiliation(s)
- Weili Cai
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
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Krajewski WA. Evidence for the nucleosome-disruption process regulated by phosphorylation of 120 kDa protein complex in Drosophila embryo cell-free system. Biochimie 2008; 90:534-41. [PMID: 18054339 DOI: 10.1016/j.biochi.2007.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Accepted: 11/06/2007] [Indexed: 11/18/2022]
Abstract
Using cell-free system derived from Drosophila embryos, we found evidence for a regulated nucleosome disruption process, which depends on the phosphorylation status of 120 kDa protein (complex). Dephosphorylation enables the remodeling activity to destabilize nucleosomes, which assume a more accessible structure, possessing increased DNase I sensitivity and high conformational flexibility of DNA; remodeling was more efficient on highly acetylated chromatin templates. This phosphorylation-regulated nucleosome destabilization, acting synergistically with histone acetylation, is discussed as a possible mechanism to provide regulated disrupt of histone-DNA interaction.
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Hartzog GA, Tamkun JW. A new role for histone tail modifications in transcription elongation. Genes Dev 2007; 21:3209-13. [DOI: 10.1101/gad.1628707] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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