1
|
Palomer X, Salvador JM, Griñán-Ferré C, Barroso E, Pallàs M, Vázquez-Carrera M. GADD45A: With or without you. Med Res Rev 2024; 44:1375-1403. [PMID: 38264852 DOI: 10.1002/med.22015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/11/2023] [Accepted: 01/09/2024] [Indexed: 01/25/2024]
Abstract
The growth arrest and DNA damage inducible (GADD)45 family includes three small and ubiquitously distributed proteins (GADD45A, GADD45B, and GADD45G) that regulate numerous cellular processes associated with stress signaling and injury response. Here, we provide a comprehensive review of the current literature investigating GADD45A, the first discovered member of the family. We first depict how its levels are regulated by a myriad of genotoxic and non-genotoxic stressors, and through the combined action of intricate transcriptional, posttranscriptional, and even, posttranslational mechanisms. GADD45A is a recognized tumor suppressor and, for this reason, we next summarize its role in cancer, as well as the different mechanisms by which it regulates cell cycle, DNA repair, and apoptosis. Beyond these most well-known actions, GADD45A may also influence catabolic and anabolic pathways in the liver, adipose tissue and skeletal muscle, among others. Not surprisingly, GADD45A may trigger AMP-activated protein kinase activity, a master regulator of metabolism, and is known to act as a transcriptional coregulator of numerous nuclear receptors. GADD45A has also been reported to display a cytoprotective role by regulating inflammation, fibrosis and oxidative stress in several organs and tissues, and is regarded an important contributor for the development of heart failure. Overall data point to that GADD45A may play an important role in metabolic, neurodegenerative and cardiovascular diseases, and also autoimmune-related disorders. Thus, the potential mechanisms by which dysregulation of GADD45A activity may contribute to the progression of these diseases are also reviewed below.
Collapse
Affiliation(s)
- Xavier Palomer
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona, Barcelona, Spain
- Spanish Biomedical Research Center in Diabetes and Associated Metabolic Diseases (CIBERDEM)-Instituto de Salud Carlos III, Madrid, Spain
- Pediatric Research Institute-Hospital Sant Joan de Déu, Esplugues de Llobregat, Barcelona, Spain
| | - Jesús M Salvador
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Madrid, Spain
| | - Christian Griñán-Ferré
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
- Institut de Neurociències, Universitat de Barcelona (NeuroUB), Barcelona, Spain
- Spanish Biomedical Research Center in Neurodegenerative Diseases (CIBERNED)-Instituto de Salud Carlos III, Madrid, Spain
| | - Emma Barroso
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona, Barcelona, Spain
- Spanish Biomedical Research Center in Diabetes and Associated Metabolic Diseases (CIBERDEM)-Instituto de Salud Carlos III, Madrid, Spain
- Pediatric Research Institute-Hospital Sant Joan de Déu, Esplugues de Llobregat, Barcelona, Spain
| | - Mercè Pallàs
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
- Institut de Neurociències, Universitat de Barcelona (NeuroUB), Barcelona, Spain
- Spanish Biomedical Research Center in Neurodegenerative Diseases (CIBERNED)-Instituto de Salud Carlos III, Madrid, Spain
| | - Manuel Vázquez-Carrera
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona, Barcelona, Spain
- Spanish Biomedical Research Center in Diabetes and Associated Metabolic Diseases (CIBERDEM)-Instituto de Salud Carlos III, Madrid, Spain
- Pediatric Research Institute-Hospital Sant Joan de Déu, Esplugues de Llobregat, Barcelona, Spain
| |
Collapse
|
2
|
Chandramouly G. Gadd45 in DNA Demethylation and DNA Repair. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1360:55-67. [PMID: 35505162 DOI: 10.1007/978-3-030-94804-7_4] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Growth arrest and DNA damage 45 (Gadd45) family genes, Gadd45A, Gadd45B, and GADD45 G are implicated as stress sensors that are rapidly induced upon genotoxic/physiological stress. They are involved in regulation of various cellular functions such as DNA repair, senescence, and cell cycle control. Gadd45 family of genes serve as tumor suppressors in response to different stimuli and defects in Gadd45 pathway can give rise to oncogenesis. More recently, Gadd45 has been shown to promote gene activation by demethylation and this function is important for transcriptional regulation and differentiation during development. Gadd45 serves as an adaptor for DNA repair factors to promote removal of 5-methylcytosine from DNA at gene specific loci. Therefore, Gadd45 serves as a powerful link between DNA repair and epigenetic gene regulation.
Collapse
Affiliation(s)
- Gurushankar Chandramouly
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, USA.
| |
Collapse
|
3
|
Tian J, Locker J. Gadd45 in the Liver: Signal Transduction and Transcriptional Mechanisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1360:87-99. [DOI: 10.1007/978-3-030-94804-7_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
4
|
Feng Y, Wang Z, Wei W, Zhang T, Li Z, Chen J, Liu K. Gadd45α is involved in regulating activity-dependent and exon-specific BDNF expression in postmitotic cortical neurons. Neuroreport 2021; 32:1147-1152. [PMID: 34334778 DOI: 10.1097/wnr.0000000000001705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE This study aimed to explore the epigenetic regulation of activity-dependent and exon-specific brain-derived neurotrophic factor (BDNF) expression under KCl depolarization in primary cortical neurons. METHODS We investigated BDNF exon I, exon IV and the growth arrest and DNA damage-inducible protein 45 alpha (Gadd45α) transcription levels under KCl-induced neuronal activation in postmitotic neurons. Gadd45α occupancy at BDNF I and IV promoter was measured by chromatin immunoprecipitation (ChIP) followed by quantitative PCR; DNA methylation level was checked by methylated DNA immunoprecipitation (MeDIP) followed by qPCR. In addition, lentiviral shRNA targeting Gadd45α was used to knockdown Gadd45α expression. RESULTS BDNF exon I and IV mRNA expressions were both highly induced by KCl depolarization. However, ChIP analysis demonstrated a significantly increased Gadd45α occupancy only at the BDNF P1 promotor, but not P4, which is associated with reducing DNA methylation within BDNF P1 promoter. Furthermore, after the lentiviral-mediated knockdown of Gadd45α, the increased Gadd45α occupancy at the BDNF P1 was inhibited, which was accompanying the complete blocking of the demethylation effect at P1. Nonetheless, the induction of BDNF exon I mRNA by KCl was only partially prevented by Gadd45α shRNA, indicting other mechanisms involved in regulating BDNF exon I expression. CONCLUSIONS DNA demethylation mediated by Gadd45α protein involves promoting the regulation of activity-dependent BDNF exon I expression in neurons.
Collapse
Affiliation(s)
- Yu Feng
- Department of Neurosurgery, Zhongnan Hospital of Wuhan University, Wuhan, China
| | | | | | | | | | | | | |
Collapse
|
5
|
Marques-Magalhães Â, Graça I, Miranda-Gonçalves V, Henrique R, Lopez M, Arimondo PB, Jerónimo C. Anti-neoplastic and demethylating activity of a newly synthetized flavanone-derived compound in Renal Cell Carcinoma cell lines. Biomed Pharmacother 2021; 141:111681. [PMID: 34139552 DOI: 10.1016/j.biopha.2021.111681] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/20/2021] [Accepted: 04/28/2021] [Indexed: 12/24/2022] Open
Abstract
Renal Cell Carcinoma (RCC) is on the top 10 of the most incident cancers worldwide, being a third of patients diagnosed with advanced disease, for which no curative therapies are currently available. Thus, new effective therapeutic strategies are urgently needed. Herein, we tested the antineoplastic effect of newly synthesized 3-nitroflavanones (MLo1302) on RCC cell lines. 786-O, Caki2, and ACHN cell lines were cultured and treated with newly synthesized 3-nitroflavanones. IC50 values were calculated based on the effect on cell viability assessed by MTT assay, after 72 h of exposure. MLo1302 displayed antineoplastic properties in RCC cell lines through marked reduction of cell viability, increased apoptosis and DNA damage, and morphometric alterations indicating a less aggressive phenotype. MLo1302 induced a significant reduction of global DNA methylation and DNMT mRNA levels, increasing global DNA hydroxymethylation and TET expression. Moreover, MLo1302 decreased DNMT3A activity in RCC cell lines, demethylated and re-expressed hypermethylated genes in CAM-generated tumors. A marked in vivo decrease in tumor growth and angiogenesis was also disclosed. MLo1302 disclosed antineoplastic and demethylating activity in RCC cell lines, constituting a potential therapeutic agent for RCC patients.
Collapse
Affiliation(s)
- Ângela Marques-Magalhães
- Cancer Biology and Epigenetics Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto 4200-072, Portugal; Institute of Biomedical Sciences Abel Salazar, University of Porto (ICBAS-UP), Rua Jorge Viterbo Ferreira 228, 4050-513 Porto, Portugal
| | - Inês Graça
- Cancer Biology and Epigenetics Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto 4200-072, Portugal
| | - Vera Miranda-Gonçalves
- Cancer Biology and Epigenetics Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto 4200-072, Portugal
| | - Rui Henrique
- Cancer Biology and Epigenetics Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto 4200-072, Portugal; Department of Pathology, Portuguese Oncology Institute of Porto (IPO Porto), Porto 4200-072, Portugal; Department of Pathology and Molecular Immunology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto 4050-313, Portugal
| | - Marie Lopez
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Université de Montpellier, ENSCM UMR 5247, Montpellier 34296, France
| | - Paola B Arimondo
- Epigenetic Chemical Biology, Institut Pasteur, CNRS UMR3523, Paris 75724, France
| | - Carmen Jerónimo
- Cancer Biology and Epigenetics Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto 4200-072, Portugal; Department of Pathology and Molecular Immunology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto 4050-313, Portugal.
| |
Collapse
|
6
|
Li Y, Coons LA, Houtman R, Carlson KE, Martin TA, Mayne CG, Melchers D, Jefferson TB, Ramsey JT, Katzenellenbogen JA, Korach KS. A mutant form of ERα associated with estrogen insensitivity affects the coupling between ligand binding and coactivator recruitment. Sci Signal 2020; 13:eaaw4653. [PMID: 32963012 PMCID: PMC7597377 DOI: 10.1126/scisignal.aaw4653] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A homozygous missense mutation in the gene encoding the estrogen receptor α (ERα) was previously identified in a female patient with estrogen insensitivity syndrome. We investigated the molecular features underlying the impaired transcriptional response of this mutant (ERα-Q375H) and four other missense mutations at this position designed to query alternative mechanisms. The identity of residue 375 greatly affected the sensitivity of the receptor to agonists without changing the ligand binding affinity. Instead, the mutations caused changes in the affinity of coactivator binding and alterations in the balance of coactivator and corepressor recruitment. Comparisons among the transcriptional regulatory responses of these six ERα genotypes to a set of ER agonists showed that both steric and electrostatic factors contributed to the functional deficits in gene regulatory activity of the mutant ERα proteins. ERα-coregulator peptide binding in vitro and RIME (rapid immunoprecipitation mass spectrometry of endogenous) analysis in cells showed that the degree of functional impairment paralleled changes in receptor-coregulator binding interactions. These findings uncover coupling between ligand binding and coregulator recruitment that affects the potency rather than the efficacy of the receptor response without substantially altering ligand binding affinity. This highlights a molecular mechanism for estrogen insensitivity syndrome involving mutations that perturb a bidirectional allosteric coupling between ligand binding and coregulator binding that determines receptor transcriptional output.
Collapse
Affiliation(s)
- Yin Li
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA.
| | - Laurel A Coons
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA
| | - René Houtman
- Precision Medicine Lab, Kloosterstraat 9, 5349 AB, Oss, Netherlands
| | - Kathryn E Carlson
- Department of Chemistry and Cancer Center, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Teresa A Martin
- Department of Chemistry and Cancer Center, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Christopher G Mayne
- Department of Chemistry and Cancer Center, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Diana Melchers
- Precision Medicine Lab, Kloosterstraat 9, 5349 AB, Oss, Netherlands
| | - Tanner B Jefferson
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA
| | - J Tyler Ramsey
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA
| | - John A Katzenellenbogen
- Department of Chemistry and Cancer Center, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Kenneth S Korach
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA.
| |
Collapse
|
7
|
Xiang Y, Wu C, Wu J, Quan W, Cheng C, Zhou J, Chen L, Xiang L, Li F, Zhang K, Ran Q, Zhang Y, Li Z. In vitro expansion affects the response of human bone marrow stromal cells to irradiation. Stem Cell Res Ther 2019; 10:82. [PMID: 30850008 PMCID: PMC6408817 DOI: 10.1186/s13287-019-1191-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 01/25/2019] [Accepted: 02/25/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Bone marrow stromal cells (BMSCs) are extensively used in regeneration therapy and cytology experiments simulate how BMSCs respond to radiation. Due to the small number and the heterogeneity of primary isolated BMSCs, extensive in vitro expansion is usually required before application, which affects the cellular characteristics and gene expression of BMSCs. However, whether the radiation response of BMSCs changes during in vitro expansion is unclear. METHODS In this study, BMSCs were passaged in vitro and irradiated at passage 6 (P6) and passage 10 (P10). Then, apoptosis, the cell cycle, senescence, the cytokine secretion and the gene expression profile were analysed for the P6, P10, and non-irradiated (control) BMSCs at different post-irradiation time points. RESULTS The P6 BMSCs had a lower percentage of apoptotic cells than the P10 BMSCs at 24 and 48 h post-irradiation but not compared to that of the controls at 2 and 8 h post-irradiation. The P6 BMSCs had a lower percentage of cells in S phase and a higher percentage in G1 phase than the P10 BMSCs at 2 and 8 h post-irradiation. The radiation had similar effects on the senescent cell level and impaired immunomodulation capacity of the P6 and P10 BMSCs. Regardless of whether they were irradiated, the P6 and P10 BMSCs always expressed a distinctive set of genes. The upregulated genes were enriched in pathways including the cell cycle, DNA replication and oocyte meiosis. Then, a subset of conserved irradiation response genes across the BMSCs was identified, comprising 12 differentially upregulated genes and 5 differentially downregulated genes. These genes were especially associated with the p53 signaling pathway, DNA damage and DNA repair. Furthermore, validation experiments revealed that the mRNA and protein levels of these conserved genes were different between the P6 and P10 BMSCs after irradiation. Weighted gene co-expression network analysis supported these findings and further revealed the effects of cell passage on the irradiation response in BMSCs. CONCLUSION The results indicated that cell passage in vitro affected the irradiation response of BMSCs via molecular mechanisms that mediated differences in apoptosis, the cell cycle, senescence and the cytokine secretion. Thus, accurate cell passage information is not only important for transplantation therapy but also for future studies on the radiation response in BMSCs.
Collapse
Affiliation(s)
- Yang Xiang
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Chun Wu
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
- Central Laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Jiang Wu
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Weili Quan
- Center for Genome Analysis, ABLife Inc., Wuhan, 430075 Hubei China
| | - Chao Cheng
- Center for Genome Analysis, ABLife Inc., Wuhan, 430075 Hubei China
| | - Jian Zhou
- Center for Genome Analysis, ABLife Inc., Wuhan, 430075 Hubei China
| | - Li Chen
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Lixin Xiang
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Fengjie Li
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Kebin Zhang
- Central Laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Qian Ran
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| | - Yi Zhang
- Center for Genome Analysis, ABLife Inc., Wuhan, 430075 Hubei China
| | - Zhongjun Li
- Department of Blood Transfusion, Irradiation biology laboratory, The Second Affiliated Hospital, Army Medical University, Xinqiao Road, Shapingba, Chongqing, 400037 China
| |
Collapse
|
8
|
Kazantseva YA, Pustylnyak YA, Pustylnyak VO. Role of Nuclear Constitutive Androstane Receptor in Regulation of Hepatocyte Proliferation and Hepatocarcinogenesis. BIOCHEMISTRY (MOSCOW) 2017; 81:338-47. [PMID: 27293091 DOI: 10.1134/s0006297916040040] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Activation of the constitutive androstane receptor (CAR) in hepatocytes occurs as a body adaptation in response to a number of external influences, and its functional activity is primarily related to induction of enzymes detoxifying xenobiotics. However, special attention was recently given to CAR due to the fact that its key role becomes unveiled in various physiological and pathophysiological processes occurring in the liver: gluconeogenesis, metabolism of fatty acids and bilirubin, hormonal regulation, proliferation of hepatocytes, and hepatocarcinogenesis. Here we review the main pathways and mechanisms that elevate hepatocyte proliferative activity related to CAR and whose disturbance may be a pivotal factor in hepatocarcinogenesis.
Collapse
Affiliation(s)
- Y A Kazantseva
- Institute of Molecular Biology and Biophysics, Novosibirsk, 630117, Russia
| | | | | |
Collapse
|
9
|
Gavin DP, Kusumo H, Sharma RP, Guizzetti M, Guidotti A, Pandey SC. Gadd45b and N-methyl-D-aspartate induced DNA demethylation in postmitotic neurons. Epigenomics 2016; 7:567-79. [PMID: 26111030 DOI: 10.2217/epi.15.12] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
AIM In nondividing neurons examine the role of Gadd45b in active 5-methylcytosine (5MC) and 5-hydroxymethylcytosine (5HMC) removal at a gene promoter highly implicated in mental illnesses and cognition, Bdnf. MATERIALS & METHODS Mouse primary cortical neuronal cultures with and without Gadd45b siRNA transfection were treated with N-methyl-d-aspartate (NMDA). Expression changes of genes reportedly involved in DNA demethylation, Bdnf mRNA and protein and 5MC and 5HMC at Bdnf promoters were measured. RESULTS Gadd45b siRNA transfection in neurons abolishes the NMDA-induced increase in Bdnf IXa mRNA and reductions in 5MC and 5HMC at the Bdnf IXa promoter. CONCLUSION These results contribute to our understanding of DNA demethylation mechanisms in neurons, and its role in regulating NMDA responsive genes implicated in mental illnesses.
Collapse
Affiliation(s)
- David P Gavin
- Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.,Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, Chicago, IL 60612, USA
| | - Handojo Kusumo
- Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.,Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, Chicago, IL 60612, USA
| | - Rajiv P Sharma
- Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.,Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, Chicago, IL 60612, USA
| | - Marina Guizzetti
- Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.,Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, Chicago, IL 60612, USA.,Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR and VA Portland Health Care System, Portland, OR
| | - Alessandro Guidotti
- Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, Chicago, IL 60612, USA
| | - Subhash C Pandey
- Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.,Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor St, Chicago, IL 60612, USA
| |
Collapse
|
10
|
Khan S, Fagerholm R, Rafiq S, Tapper W, Aittomäki K, Liu J, Blomqvist C, Eccles D, Nevanlinna H. Polymorphism at 19q13.41 Predicts Breast Cancer Survival Specifically after Endocrine Therapy. Clin Cancer Res 2015; 21:4086-4096. [PMID: 25964295 PMCID: PMC4574404 DOI: 10.1158/1078-0432.ccr-15-0296] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 04/30/2015] [Indexed: 02/07/2023]
Abstract
PURPOSE Although most patients with estrogen receptor (ER)-positive breast cancer benefit from endocrine therapies, a significant proportion do not. Our aim was to identify inherited genetic variations that might predict survival among patients receiving adjuvant endocrine therapies. EXPERIMENTAL DESIGN We performed a meta-analysis of two genome-wide studies; Helsinki Breast Cancer Study, 805 patients, with 240 receiving endocrine therapy and Prospective study of Outcomes in Sporadic versus Hereditary breast cancer, 536 patients, with 155 endocrine therapy patients, evaluating 486,478 single-nucleotide polymorphisms (SNP). The top four associations from the endocrine treatment subgroup were further investigated in two independent datasets totaling 5,011 patients, with 3,485 receiving endocrine therapy. RESULTS A meta-analysis identified a common SNP rs8113308, mapped to 19q13.41, associating with reduced survival among endocrine-treated patients [hazard ratio (HR), 1.69; 95% confidence interval (CI), 1.37-2.07; P = 6.34 × 10(-7)] and improved survival among ER-negative patients, with a similar trend in ER-positive cases not receiving endocrine therapy. In a multivariate analysis adjusted for conventional prognostic factors, we found a significant interaction between the rs8113308 and endocrine treatment, indicating a predictive, treatment-specific effect of the SNP rs8113308 on breast cancer survival, with the per-allele HR for interaction 2.16 (95% CI, 1.30-3.60; Pinteraction = 0.003) and HR = 7.77 (95% CI, 0.93-64.71) for the homozygous genotype carriers. A biologic rationale is suggested by in silico functional analyses. CONCLUSIONS Our findings suggest carrying the rs8113308 rare allele may identify patients who will not benefit from adjuvant endocrine treatment.
Collapse
Affiliation(s)
- Sofia Khan
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Rainer Fagerholm
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Sajjad Rafiq
- Faculty of Medicine, University of Southampton, Southampton General Hospital, Hants, UK
| | - William Tapper
- Faculty of Medicine, University of Southampton, Southampton General Hospital, Hants, UK
| | - Kristiina Aittomäki
- Department of Clinical Genetics, Helsinki University Hospital and Genome Scale Biology Research Program, University of Helsinki, Helsinki, Finland
| | - Jianjun Liu
- Human Genetics, Genome Institute of Singapore, 60 Biopolis St, Singapore
| | - Carl Blomqvist
- Department of Oncology, Helsinki University Hospital, Helsinki, Finland
| | - Diana Eccles
- Faculty of Medicine, University of Southampton, Southampton General Hospital, Hants, UK
| | - Heli Nevanlinna
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| |
Collapse
|
11
|
Abstract
The coactivator peroxisome proliferator-activated receptor-gamma coactivator 1 α (PGC-1α) is widely considered a central transcriptional regulator of adaptive thermogenesis in brown adipose tissue (BAT). However, mice lacking PGC-1α specifically in adipose tissue have only mild thermogenic defects, suggesting the presence of additional regulators. Using the activity of estrogen-related receptors (ERRs), downstream effectors of PGC-1α, as read-out in a high-throughput genome-wide cDNA screen, we identify here growth arrest and DNA-damage-inducible protein 45 γ (GADD45γ) as a cold-induced activator of uncoupling protein 1 (UCP1) and oxidative capacity in BAT. Mice lacking Gadd45γ have defects in Ucp1 induction and the thermogenic response to cold. GADD45γ works by activating MAPK p38, which is a potent activator of ERRβ and ERRγ transcriptional function. GADD45γ activates ERRγ independently of PGC-1 coactivators, yet synergizes with PGC-1α to induce the thermogenic program. Our findings elucidate a previously unidentified GADD45γ/p38/ERRγ pathway that regulates BAT thermogenesis and may enable new approaches for the stimulation of energy expenditure. Our study also implicates GADD45 proteins as general metabolic regulators.
Collapse
|
12
|
The role of DNA methylation in stress-related psychiatric disorders. Neuropharmacology 2014; 80:115-32. [DOI: 10.1016/j.neuropharm.2014.01.013] [Citation(s) in RCA: 219] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/19/2013] [Accepted: 01/09/2014] [Indexed: 02/06/2023]
|
13
|
Evans E, Hogarth C, Mitchell D, Griswold M. Riding the spermatogenic wave: profiling gene expression within neonatal germ and sertoli cells during a synchronized initial wave of spermatogenesis in mice. Biol Reprod 2014; 90:108. [PMID: 24719255 DOI: 10.1095/biolreprod.114.118034] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Continual sperm production relies on germ cells undergoing spermatogenesis asynchronously. As a result, the testis always contains a mixed population of germ cells at different stages of their differentiation process. The heterogeneous nature of the testis makes profiling gene expression within Sertoli cells or specific populations of germ cells impossible when a wild-type testis is assessed. We recently reported a unique method for synchronizing spermatogenesis without affecting fertility by manipulating RA levels within the neonatal testis. Using this protocol, combined with the RiboTag transgenic mouse line, we have mapped the Sertoli and germ cell translatome during the initial synchronized wave of spermatogenesis. Using microarray analysis, we identified 392 and 194 germ cell and Sertoli cells transcripts, respectively, that dynamically change during spermatogonial differentiation, division, and the onset of meiosis. Functional annotation clustering revealed that transcripts enriched in germ cells were mostly associated with meiosis (21 transcripts), chromatin organization (12 transcripts), and cell cycle (3 transcripts). In addition, glycoproteins (65 transcripts), cell adhesion (15 transcripts), and cell junction (13 transcripts) transcripts were overrepresented in the Sertoli cell-enriched list. These datasets represent the first transcriptional analysis of spermatogonial differentiation, division, and meiotic onset. These data suggest that several of the genes encoding meiotic proteins are expressed and are actively being translated well before germ cells enter meiosis. In addition, this study provides novel candidate genes, Asf1b and Esyt3, that may be involved in the regulation of spermatogonial chromatin reorganization, germ-Sertoli cell interactions, and/or blood-testis barrier formation.
Collapse
Affiliation(s)
- Elizabeth Evans
- School of Molecular Biosciences and The Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Cathryn Hogarth
- School of Molecular Biosciences and The Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Debra Mitchell
- School of Molecular Biosciences and The Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Michael Griswold
- School of Molecular Biosciences and The Center for Reproductive Biology, Washington State University, Pullman, Washington
| |
Collapse
|
14
|
Gavin DP, Chase KA, Sharma RP. Active DNA demethylation in post-mitotic neurons: a reason for optimism. Neuropharmacology 2013; 75:233-45. [PMID: 23958448 DOI: 10.1016/j.neuropharm.2013.07.036] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 07/22/2013] [Accepted: 07/30/2013] [Indexed: 12/13/2022]
Abstract
Over the last several years proteins involved in base excision repair (BER) have been implicated in active DNA demethylation. We review the literature supporting BER as a means of active DNA demethylation, and explain how the various components function and cooperate to remove the potentially most enduring means of epigenetic gene regulation. Recent evidence indicates that the same pathways implicated during periods of widespread DNA demethylation, such as the erasure of methyl marks in the paternal pronucleus soon after fertilization, are operational in post-mitotic neurons. Neuronal functional identities, defined here as the result of a combination of neuronal subtype, location, and synaptic connections are largely maintained through DNA methylation. Chronic mental illnesses, such as schizophrenia, may be the result of both altered neurotransmitter levels and neurons that have assumed dysfunctional neuronal identities. A limitation of most current psychopharmacological agents is their focus on the former, while not addressing the more profound latter pathophysiological process. Previously, it was believed that active DNA demethylation in post-mitotic neurons was rare if not impossible. If this were the case, then reversing the factors that maintain neuronal identity, would be highly unlikely. The emergence of an active DNA demethylation pathway in the brain is a reason for great optimism in psychiatry as it provides a means by which previously pathological neurons may be reprogrammed to serve a more favorable role. Agents targeting epigenetic processes have shown much promise in this regard, and may lead to substantial gains over traditional pharmacological approaches.
Collapse
Affiliation(s)
- David P Gavin
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL 60612, USA; Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA.
| | - Kayla A Chase
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL 60612, USA
| | - Rajiv P Sharma
- The Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL 60612, USA; Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL 60612, USA
| |
Collapse
|
15
|
Schäfer A, Karaulanov E, Stapf U, Döderlein G, Niehrs C. Ing1 functions in DNA demethylation by directing Gadd45a to H3K4me3. Genes Dev 2013; 27:261-73. [PMID: 23388825 DOI: 10.1101/gad.186916.112] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Active DNA demethylation regulates epigenetic gene activation in numerous processes, but how the target site specificity of DNA demethylation is determined and what factors are involved are still poorly understood. Here we show that the tumor suppressor inhibitor of growth protein 1 (Ing1) is required for targeting active DNA demethylation. Ing1 functions by recruiting the regulator of DNA demethylation growth arrest and DNA damage protein 45a (Gadd45a) to histone H3 trimethylated at Lys 4 (H3K4me3). We show that reduced H3K4 methylation impairs recruitment of Gadd45a/Ing1 and gene-specific DNA demethylation. Our results indicate that histone methylation directs DNA demethylation.
Collapse
|
16
|
Schäfer A. Gadd45 proteins: key players of repair-mediated DNA demethylation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 793:35-50. [PMID: 24104472 DOI: 10.1007/978-1-4614-8289-5_3] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The three growth arrest and DNA damage 45 (Gadd45) family genes encode for stress-response proteins that are rapidly induced upon cellular stress or differentiation cues. They are well-characterized regulators of cell cycle, senescence, survival, and apoptosis. More recently, it has become clear that Gadd45 proteins promote active DNA demethylation thereby mediating gene activation. This epigenetic function of Gadd45 is important for differentiation and transcriptional regulation during development. Mechanistically, Gadd45 acts as an adapter for DNA repair factors at gene-specific loci to promote removal of 5-methylcytosine from DNA. Hence, Gadd45 is a nexus between DNA repair and epigenetic gene regulation.
Collapse
|
17
|
Grayson DR, Guidotti A. The dynamics of DNA methylation in schizophrenia and related psychiatric disorders. Neuropsychopharmacology 2013; 38:138-66. [PMID: 22948975 PMCID: PMC3521968 DOI: 10.1038/npp.2012.125] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 05/08/2012] [Accepted: 05/09/2012] [Indexed: 02/06/2023]
Abstract
Major psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BP) with psychosis (BP+) express a complex symptomatology characterized by positive symptoms, negative symptoms, and cognitive impairment. Postmortem studies of human SZ and BP+ brains show considerable alterations in the transcriptome of a variety of cortical structures, including multiple mRNAs that are downregulated in both inhibitory GABAergic and excitatory pyramidal neurons compared with non-psychiatric subjects (NPS). Several reports show increased expression of DNA methyltransferases in telencephalic GABAergic neurons. Accumulating evidence suggests a critical role for altered DNA methylation processes in the pathogenesis of SZ and related psychiatric disorders. The establishment and maintenance of CpG site methylation is essential during central nervous system differentiation and this methylation has been implicated in synaptic plasticity, learning, and memory. Atypical hypermethylation of candidate gene promoters expressed in GABAergic neurons is associated with transcriptional downregulation of the corresponding mRNAs, including glutamic acid decarboxylase 67 (GAD67) and reelin (RELN). Recent reports indicate that the methylation status of promoter proximal CpG dinucleotides is in a dynamic balance between DNA methylation and DNA hydroxymethylation. Hydroxymethylation and subsequent DNA demethylation is more complex and involves additional proteins downstream of 5-hydroxymethylcytosine, including members of the base excision repair (BER) pathway. Recent advances in our understanding of altered CpG methylation, hydroxymethylation, and active DNA demethylation provide a framework for the identification of new targets, which may be exploited for the pharmacological intervention of the psychosis associated with SZ and possibly BP+.
Collapse
Affiliation(s)
- Dennis R Grayson
- The Psychiatric Institute, Department of Psychiatry, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
| | | |
Collapse
|
18
|
Gadd45 in the Liver: Signal Transduction and Transcriptional Mechanisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 793:69-80. [DOI: 10.1007/978-1-4614-8289-5_5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
19
|
Moskalev A, Plyusnina E, Shaposhnikov M, Shilova L, Kazachenok A, Zhavoronkov A. The role of D-GADD45 in oxidative, thermal and genotoxic stress resistance. Cell Cycle 2012; 11:4222-41. [PMID: 23095639 PMCID: PMC3524218 DOI: 10.4161/cc.22545] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
There is a relationship between various cellular stress factors and aging. In earlier studies, we demonstrated that overexpression of the D-GADD45 gene increases the life span of Drosophila melanogaster. In this study, we investigate the relationship between D-GADD45 activity and resistance to oxidative, genotoxic and thermal stresses as well as starvation. In most cases, flies with constitutive and conditional D-GADD45 overexpression in the nervous system were more stress-resistant than ones without overexpression. At the same time, most of the studied stress factors increased D-GADD45 expression in the wild-type strain. The lifespan-extending effect of D-GADD45 overexpression was also retained after exposure to chronic and acute gamma-irradiation, with doses of 40 сGy and 30 Gy, respectively. However, knocking out D-GADD45 resulted in a significant reduction in lifespan, lack of radiation hormesis and radioadaptive response. A dramatic decrease in the spontaneous level of D-GADD45 expression was observed in the nervous system as age progressed, which may be one of the causes of the age-related deterioration of organismal stress resistance. Thus, D-GADD45 expression is activated by most of the studied stress factors, and D-GADD45 overexpression resulted in an increase of stress resistance.
Collapse
Affiliation(s)
- Alexey Moskalev
- Laboratory of Molecular Radiobiology and Gerontology, Institute of Biology, Komi Science Center of Russian Academy of Sciences, Syktyvkar, Russia.
| | | | | | | | | | | |
Collapse
|
20
|
Ebert SM, Dyle MC, Kunkel SD, Bullard SA, Bongers KS, Fox DK, Dierdorff JM, Foster ED, Adams CM. Stress-induced skeletal muscle Gadd45a expression reprograms myonuclei and causes muscle atrophy. J Biol Chem 2012; 287:27290-301. [PMID: 22692209 DOI: 10.1074/jbc.m112.374777] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Diverse stresses including starvation and muscle disuse cause skeletal muscle atrophy. However, the molecular mechanisms of muscle atrophy are complex and not well understood. Here, we demonstrate that growth arrest and DNA damage-inducible 45a protein (Gadd45a) is a critical mediator of muscle atrophy. We identified Gadd45a through an unbiased search for potential downstream mediators of the stress-inducible, pro-atrophy transcription factor ATF4. We show that Gadd45a is required for skeletal muscle atrophy induced by three distinct skeletal muscle stresses: fasting, muscle immobilization, and muscle denervation. Conversely, forced expression of Gadd45a in muscle or cultured myotubes induces atrophy in the absence of upstream stress. We show that muscle-specific ATF4 knock-out mice have a reduced capacity to induce Gadd45a mRNA in response to stress, and as a result, they undergo less atrophy in response to fasting or muscle immobilization. Interestingly, Gadd45a is a myonuclear protein that induces myonuclear remodeling and a comprehensive program for muscle atrophy. Gadd45a represses genes involved in anabolic signaling and energy production, and it induces pro-atrophy genes. As a result, Gadd45a reduces multiple barriers to muscle atrophy (including PGC-1α, Akt activity, and protein synthesis) and stimulates pro-atrophy mechanisms (including autophagy and caspase-mediated proteolysis). These results elucidate a critical stress-induced pathway that reprograms muscle gene expression to cause atrophy.
Collapse
Affiliation(s)
- Scott M Ebert
- Department of and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa, Iowa City, Iowa 52242, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Niehrs C, Schäfer A. Active DNA demethylation by Gadd45 and DNA repair. Trends Cell Biol 2012; 22:220-7. [PMID: 22341196 DOI: 10.1016/j.tcb.2012.01.002] [Citation(s) in RCA: 178] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 12/23/2011] [Accepted: 01/05/2012] [Indexed: 11/13/2022]
Abstract
How DNA methylation patterns are established, maintained and remodeled is incompletely understood, however, it has become clear that DNA methylation is reversible and dynamic as a result of enzymatic DNA demethylation. Several different mechanisms that may account for demethylation have recently been put forward and all seem to involve DNA repair. Here, we review DNA demethylation mediated by multifunctional growth arrest and DNA damage 45 (Gadd45) protein family members which mediate DNA demethylation during cell differentiation and stress response. Gadd45 recruits nucleotide and/or base excision repair factors to gene-specific loci and acts as an adapter between repair factors and chromatin, thereby creating a nexus between epigenetics and DNA repair.
Collapse
|
22
|
Currie RA. Toxicogenomics: the challenges and opportunities to identify biomarkers, signatures and thresholds to support mode-of-action. Mutat Res 2012; 746:97-103. [PMID: 22445948 DOI: 10.1016/j.mrgentox.2012.03.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 03/05/2012] [Indexed: 12/20/2022]
Abstract
Toxicogenomics (TGx) can be defined as the application of "omics" techniques to toxicology and risk assessment. By identifying molecular changes associated with toxicity, TGx data might assist hazard identification and investigate causes. Early technical challenges were evaluated and addressed by consortia (e.g. ISLI/HESI and the Microarray Quality Control consortium), which demonstrated that TGx gave reliable and reproducible information. The MAQC also produced "best practice on signature generation" after conducting an extensive evaluation of different methods on common datasets. Two findings of note were the need for methods that control batch variability, and that the predictive ability of a signature changes in concert with the variability of the endpoint. The key challenge remaining is data interpretation, because TGx can identify molecular changes that are causal, associated with or incidental to toxicity. Application of Bradford Hill's tests for causation, which are used to build mode of action (MOA) arguments, can produce reasonable hypotheses linking altered pathways to phenotypic changes. However, challenges in interpretation still remain: are all pathway changes equal, which are most important and plausibly linked to toxicity? Therefore the expert judgement of the toxicologist is still needed. There are theoretical reasons why consistent alterations across a metabolic pathway are important, but similar changes in signalling pathways may not alter information flow. At the molecular level thresholds may be due to the inherent properties of the regulatory network, for example switch-like behaviours from some network motifs (e.g. positive feedback) in the perturbed pathway leading to the toxicity. The application of systems biology methods to TGx data can generate hypotheses that explain why a threshold response exists. However, are we adequately trained to make these judgments? There is a need for collaborative efforts between regulators, industry and academia to properly define how these technologies can be applied using appropriate case-studies.
Collapse
|
23
|
Kaufmann LT, Gierl MS, Niehrs C. Gadd45a, Gadd45b and Gadd45g expression during mouse embryonic development. Gene Expr Patterns 2011; 11:465-70. [DOI: 10.1016/j.gep.2011.07.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Revised: 07/28/2011] [Accepted: 07/29/2011] [Indexed: 11/29/2022]
|
24
|
Tian J, Huang H, Hoffman B, Liebermann DA, Ledda-Columbano GM, Columbano A, Locker J. Gadd45β is an inducible coactivator of transcription that facilitates rapid liver growth in mice. J Clin Invest 2011; 121:4491-502. [PMID: 21965327 DOI: 10.1172/jci38760] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 08/24/2011] [Indexed: 12/16/2022] Open
Abstract
The growth arrest and DNA damage-inducible 45 (Gadd45) proteins act in many cellular processes. In the liver, Gadd45b (encoding Gadd45β) is the gene most strongly induced early during both compensatory regeneration and drug-induced hyperplasia. The latter response is associated with the dramatic and rapid hepatocyte growth that follows administration of the xenobiotic TCPOBOP (1,4-bis[2-(3,5)-dichoropyridyloxy] benzene), a ligand of the nuclear receptor constitutive androstane receptor (CAR). Here, we have shown that Gadd45b-/- mice have intact proliferative responses following administration of a single dose of TCPOBOP, but marked growth delays. Moreover, early transcriptional stimulation of CAR target genes was weaker in Gadd45b-/- mice than in wild-type animals, and more genes were downregulated. Gadd45β was then found to have a direct role in transcription by physically binding to CAR, and TCPOBOP treatment caused both proteins to localize to a regulatory element for the CAR target gene cytochrome P450 2b10 (Cyp2b10). Further analysis defined separate Gadd45β domains that mediated binding to CAR and transcriptional activation. Although baseline hepatic expression of Gadd45b was broadly comparable to that of other coactivators, its 140-fold stimulation by TCPOBOP was striking and unique. The induction of Gadd45β is therefore a response that facilitates increased transcription, allowing rapid expansion of liver mass for protection against xenobiotic insults.
Collapse
Affiliation(s)
- Jianmin Tian
- Department of Pathology and Marion Bessin Liver Center, Albert Einstein College of Medicine, New York, New York, USA
| | | | | | | | | | | | | |
Collapse
|
25
|
Kaufmann LT, Niehrs C. Gadd45a and Gadd45g regulate neural development and exit from pluripotency in Xenopus. Mech Dev 2011; 128:401-11. [PMID: 21854844 DOI: 10.1016/j.mod.2011.08.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 08/01/2011] [Accepted: 08/03/2011] [Indexed: 01/07/2023]
Abstract
Gadd45 genes encode a small family of multifunctional stress response proteins, mediating cell proliferation, apoptosis, DNA repair and DNA demethylation. Their role during embryonic development is incompletely understood. Here we identified Xenopus Gadd45b, compared Gadd45a, Gadd45b and Gadd45g expression during Xenopus embryogenesis, and characterized their gain and loss of function phenotypes. Gadd45a and Gadd45g act redundantly and double Morpholino knock down leads to pleiotropic phenotypes, including shortened axes, head defects and misgastrulation. In contrast, Gadd45b, which is expressed at very low levels, shows little effect upon knock down or overexpression. Gadd45ag double Morphants show reduced neural cell proliferation and downregulation of pan-neural and neural crest markers. In contrast, Gadd45ag Morphants display increased expression of multipotency marker genes including Xenopus oct4 homologs as well as gastrula markers, while mesodermal markers are downregulated. The results indicate that Gadd45ag are required for early embryonic cells to exit pluripotency and enter differentiation.
Collapse
Affiliation(s)
- Lilian T Kaufmann
- Division of Molecular Embryology, DKFZ-ZMBH Alliance, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 581, Heidelberg, Germany
| | | |
Collapse
|
26
|
Park EJ, Kondratyuk TP, Morrell A, Kiselev E, Conda-Sheridan M, Cushman M, Ahn S, Choi Y, White JJ, van Breemen RB, Pezzuto JM. Induction of retinoid X receptor activity and consequent upregulation of p21WAF1/CIP1 by indenoisoquinolines in MCF7 cells. Cancer Prev Res (Phila) 2011; 4:592-607. [PMID: 21464033 DOI: 10.1158/1940-6207.capr-10-0004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Retinoid X receptor (RXR) has been targeted for the chemoprevention and treatment of cancer. To discover potential agents acting through RXRs, we utilized an RXR response element (RXRE)-luciferase reporter gene assay. Following extensive screening, 3-amino-6-(3-aminopropyl)-5,6-dihydro-5,11-dioxo-11H-indeno[1,2-c]isoquinoline dihydrochloride (AM6-36) was found to induce RXRE-luciferase activities. AM6-36 inhibited COX-2 expression and anchorage-independent growth with 12-O-tetradecanoylphorbol 13-acetate-stimulated JB6 Cl41 cells, induced the expression of CD38 in HL-60 cells, and attenuated the growth of N-methyl-N-nitrosourea-induced mammary tumors in rats. Consistent with other reports describing the antiproliferative effects of RXR agonists in breast cancers, AM6-36 showed growth inhibition with cultured MCF7 breast cancer cells, accompanied by G(2)/M-phase arrest at lower concentrations and enhanced S-phase arrest at higher concentrations. On the basis of DNA microarray analysis, AM6-36 upregulated the expression of CDKN1A, a target gene of RXR, by 35-fold. In accord with this response, the expression of the corresponding protein, p21(WAF1/CIP1), was increased in the presence of AM6-36. Induction of p21 by AM6-36 was abrogated following transient knockdown of RXRα, demonstrating that the effect of AM6-36 on the expression of p21 is closely related to modulation of RXRα transcriptional activity. Intestinal permeability was suggested with Caco-2 cells and limited metabolism resulted when AM6-36 was incubated with human liver microsomes. Oral administration with rats resulted in 0.8 μg/mL, 4.3 μg/g, and 0.3 μg/g in serum, liver, and mammary gland, respectively. In sum, these data suggest that AM6-36 is a promising lead for the treatment or prevention of breast cancer and provide a strong rationale for testing in more advanced antitumor systems.
Collapse
Affiliation(s)
- Eun-Jung Park
- College of Pharmacy, University of Hawaii at Hilo, 34 Rainbow Drive, Hilo, HI 96720, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Cortellino S, Xu J, Sannai M, Moore R, Caretti E, Cigliano A, Le Coz M, Devarajan K, Wessels A, Soprano D, Abramowitz LK, Bartolomei MS, Rambow F, Bassi MR, Bruno T, Fanciulli M, Renner C, Klein-Szanto AJ, Matsumoto Y, Kobi D, Davidson I, Alberti C, Larue L, Bellacosa A. Thymine DNA glycosylase is essential for active DNA demethylation by linked deamination-base excision repair. Cell 2011; 146:67-79. [PMID: 21722948 DOI: 10.1016/j.cell.2011.06.020] [Citation(s) in RCA: 595] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 05/17/2011] [Accepted: 06/12/2011] [Indexed: 01/19/2023]
Abstract
DNA methylation is a major epigenetic mechanism for gene silencing. Whereas methyltransferases mediate cytosine methylation, it is less clear how unmethylated regions in mammalian genomes are protected from de novo methylation and whether an active demethylating activity is involved. Here, we show that either knockout or catalytic inactivation of the DNA repair enzyme thymine DNA glycosylase (TDG) leads to embryonic lethality in mice. TDG is necessary for recruiting p300 to retinoic acid (RA)-regulated promoters, protection of CpG islands from hypermethylation, and active demethylation of tissue-specific developmentally and hormonally regulated promoters and enhancers. TDG interacts with the deaminase AID and the damage response protein GADD45a. These findings highlight a dual role for TDG in promoting proper epigenetic states during development and suggest a two-step mechanism for DNA demethylation in mammals, whereby 5-methylcytosine and 5-hydroxymethylcytosine are first deaminated by AID to thymine and 5-hydroxymethyluracil, respectively, followed by TDG-mediated thymine and 5-hydroxymethyluracil excision repair.
Collapse
Affiliation(s)
- Salvatore Cortellino
- Cancer Biology Program and Epigenetics and Progenitor Cells Keystone Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Berger MJ, Minnerath SR, Adams SD, Tigges BM, Sprague SL, McKenna DH. Gene expression changes with differentiation of cord blood stem cells to respiratory epithelial cells: a preliminary observation. Stem Cell Res Ther 2011; 2:19. [PMID: 21489244 PMCID: PMC3226290 DOI: 10.1186/scrt60] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 03/17/2011] [Accepted: 04/13/2011] [Indexed: 12/12/2022] Open
Abstract
Introduction Owing to wide availability, low cost and avoidance of ethical concerns, umbilical cord blood (UCB) provides an attractive source of stem cells for investigational and therapeutic uses. In this study, we sought to characterize the gene expression changes as stem cells from UCB differentiate toward alveolar type II pneumocytes (ATII). Methods Control and experimental cells were cultured in maintenance medium (mesenchymal stem cell growth medium) or differentiation medium (small airway growth medium (SAGM)), respectively, for 8 days. Total RNA was isolated from control and experimental groups for gene expression profiling and real-time polymerase chain reaction assay. Results Analysis of only mixed cell lines (n = 2) with parameters including a P value of 0.01 and an intergroup gap of 2.0 yielded a set of 373 differentially expressed genes. Prominently upregulated genes included several genes associated with ATII cells and also lung cancers: ALDH3A1, VDR and CHKA. Several upregulated genes have been shown to be integral or related to ATII functioning: SGK1, HSD17B11 and LEPR. Finally, several upregulated genes appear to play a role in lung cancers, including FDXR and GP96. Downregulated genes appear to be associated with bone, muscle and central nervous system tissues as well as other widespread tissues. Conclusions To the best of our knowledge, this accounting of the gene expression changes associated with the differentiation of a human UCB-derived stem cell toward an ATII cell represents the first such effort. Dissecting which components of SAGM affect specific gene regulation events is warranted.
Collapse
Affiliation(s)
- Michael J Berger
- Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware Street SE, MMC609, Minneapolis, MN 5545, USA.
| | | | | | | | | | | |
Collapse
|
29
|
Sytnikova YA, Kubarenko AV, Schäfer A, Weber ANR, Niehrs C. Gadd45a is an RNA binding protein and is localized in nuclear speckles. PLoS One 2011; 6:e14500. [PMID: 21249130 PMCID: PMC3017548 DOI: 10.1371/journal.pone.0014500] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 12/09/2010] [Indexed: 01/06/2023] Open
Abstract
Background The Gadd45 proteins play important roles in growth control, maintenance of genomic stability, DNA repair, and apoptosis. Recently, Gadd45 proteins have also been implicated in epigenetic gene regulation by promoting active DNA demethylation. Gadd45 proteins have sequence homology with the L7Ae/L30e/S12e RNA binding superfamily of ribosomal proteins, which raises the question if they may interact directly with nucleic acids. Principal Findings Here we show that Gadd45a binds RNA but not single- or double stranded DNA or methylated DNA in vitro. Sucrose density gradient centrifugation experiments demonstrate that Gadd45a is present in high molecular weight particles, which are RNase sensitive. Gadd45a displays RNase-sensitive colocalization in nuclear speckles with the RNA helicase p68 and the RNA binding protein SC35. A K45A point mutation defective in RNA binding was still active in DNA demethylation. This suggests that RNA binding is not absolutely essential for demethylation of an artificial substrate. A point mutation at G39 impared RNA binding, nuclear speckle localization and DNA demethylation, emphasizing its relevance for Gadd45a function. Significance The results implicate RNA in Gadd45a function and suggest that Gadd45a is associated with a ribonucleoprotein particle.
Collapse
Affiliation(s)
- Yuliya A. Sytnikova
- Division of Molecular Embryology, DKFZ-ZMBH Alliance, Krebsforschungszentrum, Heidelberg, Germany
| | - Andriy V. Kubarenko
- Division of Toll-like Receptors and Cancer, Deutsches Krebsforschungszentrum, Heidelberg, Germany
| | - Andrea Schäfer
- Division of Molecular Embryology, DKFZ-ZMBH Alliance, Krebsforschungszentrum, Heidelberg, Germany
| | - Alexander N. R. Weber
- Division of Toll-like Receptors and Cancer, Deutsches Krebsforschungszentrum, Heidelberg, Germany
| | - Christof Niehrs
- Division of Molecular Embryology, DKFZ-ZMBH Alliance, Krebsforschungszentrum, Heidelberg, Germany
- Institute of Molecular Biology (IMB), Mainz, Germany
- * E-mail:
| |
Collapse
|
30
|
Kodama S, Negishi M. Pregnane X receptor PXR activates the GADD45beta gene, eliciting the p38 MAPK signal and cell migration. J Biol Chem 2010; 286:3570-8. [PMID: 21127053 DOI: 10.1074/jbc.m110.179812] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pregnane X receptor (PXR) was originally characterized as a transcription factor that induces hepatic drug metabolism by activating cytochrome P450 genes. Here we have now demonstrated a novel function of PXR, that of eliciting p38 mitogen-activated protein kinase (MAPK) phosphorylation for cell migration. Upon xenobiotic activation of ectopic human PXR, human hepatocellular carcinoma HepG2 cells were found to exhibit increased phosphorylation of p38 MAPK and to subsequently change morphology and migrate. p38 MAPK was responsible for the regulation of these morphological changes and cell migration because the p38 MAPK inhibitor SB239063 repressed both. Prior to this phosphorylation, PXR directly activated the early response GADD45β gene by binding to a distal direct repeat 4 site of the GADD45β promoter. Ectopic expression of GADD45β increased p38 MAPK phosphorylation, whereas siRNA knockdown of GADD45β decreased the PXR-induced p38 MAPK phosphorylation, confirming that GADD45β can regulate PXR-induced p38 MAPK phosphorylation in HepG2 cells. These results indicate that PXR activates the GADD45β gene, increasing p38 MAPK phosphorylation, and leading HepG2 cells to change morphology and migrate. The GADD45β gene is a direct target for PXR, eliciting cell signals to regulate various cellular functions.
Collapse
Affiliation(s)
- Susumu Kodama
- Pharmacogenetics Section, Laboratory of Reproductive and Developmental Toxicology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA
| | | |
Collapse
|
31
|
Kang HJ, Hong YB, Kim HJ, Bae I. CR6-interacting factor 1 (CRIF1) regulates NF-E2-related factor 2 (NRF2) protein stability by proteasome-mediated degradation. J Biol Chem 2010; 285:21258-68. [PMID: 20427290 PMCID: PMC2898415 DOI: 10.1074/jbc.m109.084590] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Free radicals generated by oxidative stress cause damage that can contribute to numerous chronic diseases. Mammalian cells respond to this damage by increased transcription of cytoprotective phase II genes, which are regulated by NRF2. Previously, it has been shown that NRF2 protein levels increase after oxidative stress because its negative regulator, KEAP1, loses its ability to bind NRF2 and cause its proteasome-mediated degradation during oxidative stress. Here, we show that CRIF1, a protein previously known as cell cycle regulator and transcription cofactor, is also able to negatively regulate NRF2 protein stability. However, in contrast to KEAP1, which regulates NRF2 stability only under normal reducing conditions, CRIF1 regulates NRF2 stability and its target gene expression under both reducing and oxidative stress conditions. Thus, CRIF1-NRF2 interactions and their consequences are redox-independent. In addition, we found that CRIF1, unlike KEAP1 (which only interacts with N-terminal region of NRF2), physically interacts with both N- and C-terminal regions of NRF2 and promotes NRF2 ubiquitination and subsequent proteasome-mediated NRF2 protein degradation.
Collapse
Affiliation(s)
- Hyo Jin Kang
- Departments of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057, USA
| | | | | | | |
Collapse
|
32
|
Nuclear receptor-induced chromosomal proximity and DNA breaks underlie specific translocations in cancer. Cell 2010; 139:1069-83. [PMID: 19962179 DOI: 10.1016/j.cell.2009.11.030] [Citation(s) in RCA: 447] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2008] [Revised: 04/20/2009] [Accepted: 11/11/2009] [Indexed: 01/26/2023]
Abstract
Chromosomal translocations are a hallmark of leukemia/lymphoma and also appear in solid tumors, but the underlying mechanism remains elusive. By establishing a cellular model that mimics the relative frequency of authentic translocation events without proliferation selection, we report mechanisms of nuclear receptor-dependent tumor translocations. Intronic binding of liganded androgen receptor (AR) first juxtaposes translocation loci by triggering intra- and interchromosomal interactions. AR then promotes site-specific DNA double-stranded breaks (DSBs) at translocation loci by recruiting two types of enzymatic activities induced by genotoxic stress and liganded AR, including activation-induced cytidine deaminase and the LINE-1 repeat-encoded ORF2 endonuclease. These enzymes synergistically generate site-selective DSBs at juxtaposed translocation loci that are ligated by nonhomologous end joining pathway for specific translocations. Our data suggest that the confluence of two parallel pathways initiated by liganded nuclear receptor and genotoxic stress underlies nonrandom tumor translocations, which may function in many types of tumors and pathological processes.
Collapse
|
33
|
Ma DK, Guo JU, Ming GL, Song H. DNA excision repair proteins and Gadd45 as molecular players for active DNA demethylation. Cell Cycle 2009; 8:1526-31. [PMID: 19377292 PMCID: PMC2738863 DOI: 10.4161/cc.8.10.8500] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
DNA cytosine methylation represents an intrinsic modification signal of the genome that plays important roles in heritable gene silencing, heterochromatin formation and certain transgenerational epigenetic inheritance. In contrast to the process of DNA methylation that is catalyzed by specific classes of methyltransferases, molecular players underlying active DNA demethylation have long been elusive. Emerging biochemical and functional evidence suggests that active DNA demethylation in vertebrates can be mediated through DNA excision repair enzymes, similar to the well-known repair-based DNA demethylation mechanism in Arabidopsis. As key regulators, non-enzymatic Gadd45 proteins function to recruit enzymatic machineries and promote coupling of deamination, base and nucleotide-excision repair in the process of DNA demethylation. In this article, we review recent findings and discuss functional and evolutionary implications of such mechanisms underlying active DNA demethylation.
Collapse
Affiliation(s)
- Dengke K. Ma
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Junjie U. Guo
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- The Solomon Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Guo-li Ming
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- The Solomon Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Hongjun Song
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- The Solomon Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| |
Collapse
|
34
|
Active DNA demethylation and DNA repair. Differentiation 2008; 77:1-11. [PMID: 19281759 DOI: 10.1016/j.diff.2008.09.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 06/19/2008] [Accepted: 07/07/2008] [Indexed: 12/17/2022]
Abstract
DNA methylation on cytosine is an epigenetic modification and is essential for gene regulation and genome stability in vertebrates. Traditionally DNA methylation was considered as the most stable of all heritable epigenetic marks. However, it has become clear that DNA methylation is reversible by enzymatic "active" DNA demethylation, with examples in plant cells, animal development and immune cells. It emerges that "pruning" of methylated cytosines by active DNA demethylation is an important determinant for the DNA methylation signature of a cell. Work in plants and animals shows that demethylation occurs by base excision and nucleotide excision repair. Far from merely protecting genomic integrity from environmental insult, DNA repair is therefore at the heart of an epigenetic activation process.
Collapse
|
35
|
Wang Z, Liu BC, Lin GT, Lin CS, Lue TF, Willingham E, Baskin LS. Up-Regulation of Estrogen Responsive Genes in Hypospadias: Microarray Analysis. J Urol 2007; 177:1939-46. [PMID: 17437852 DOI: 10.1016/j.juro.2007.01.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Indexed: 11/24/2022]
Abstract
PURPOSE An unexplained increase in the incidence of hypospadias has been reported, and yet to our knowledge the molecular events and their regulation leading to hypospadias remain unknown, although environmental compounds capable of endocrine activity are suspected. We screened on a global scale abnormalities in gene expression in human hypospadiac tissue compared to those in nonhypospadiac tissue. Additionally, microarray analysis of tissue from a pair of fraternal twins, including 1 with and 1 without hypospadias, served as a control for genetic variability. We hypothesized that gene expression would differ between hypospadiac vs nonhypospadiac tissue and fraternal twin data would show patterns similar to those of group data on hypospadiac and nonhypospadiac tissue. MATERIALS AND METHODS Microarray analysis was performed on tissue from patients with and without hypospadias, and from a pair of fraternal twins, including 1 with and 1 without hypospadias. Analysis incorporated the expression of 22,000 genes. RESULTS We found significant differences in gene expression, specifically with a group of genes, including CYR61, CTGF, ATF3 and GADD45beta, known to be responsive to estrogen or to interact with estrogen receptor. CONCLUSIONS Our findings provide support for the hypothesis that endocrine active environmental compounds may contribute to the development of hypospadias. Additionally, regulation of these genes may have a role in formation of the urethra.
Collapse
Affiliation(s)
- Zhong Wang
- Departments of Urology, Ninth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
36
|
Barreto G, Schäfer A, Marhold J, Stach D, Swaminathan SK, Handa V, Döderlein G, Maltry N, Wu W, Lyko F, Niehrs C. Gadd45a promotes epigenetic gene activation by repair-mediated DNA demethylation. Nature 2007; 445:671-5. [PMID: 17268471 DOI: 10.1038/nature05515] [Citation(s) in RCA: 553] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Accepted: 12/04/2006] [Indexed: 12/21/2022]
Abstract
DNA methylation is an epigenetic modification that is essential for gene silencing and genome stability in many organisms. Although methyltransferases that promote DNA methylation are well characterized, the molecular mechanism underlying active DNA demethylation is poorly understood and controversial. Here we show that Gadd45a (growth arrest and DNA-damage-inducible protein 45 alpha), a nuclear protein involved in maintenance of genomic stability, DNA repair and suppression of cell growth, has a key role in active DNA demethylation. Gadd45a overexpression activates methylation-silenced reporter plasmids and promotes global DNA demethylation. Gadd45a knockdown silences gene expression and leads to DNA hypermethylation. During active demethylation of oct4 in Xenopus laevis oocytes, Gadd45a is specifically recruited to the site of demethylation. Active demethylation occurs by DNA repair and Gadd45a interacts with and requires the DNA repair endonuclease XPG. We conclude that Gadd45a relieves epigenetic gene silencing by promoting DNA repair, which erases methylation marks.
Collapse
Affiliation(s)
- Guillermo Barreto
- Division of Molecular Embryology, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Kang HJ, Kim HJ, Kim SK, Barouki R, Cho CH, Khanna KK, Rosen EM, Bae I. BRCA1 Modulates Xenobiotic Stress-inducible Gene Expression by Interacting with ARNT in Human Breast Cancer Cells. J Biol Chem 2006; 281:14654-62. [PMID: 16567799 DOI: 10.1074/jbc.m601613200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Previously, we have reported that BRCA1 regulates the expression of various classes of genes, including genes involved in xenobiotic stress responses (Bae, I., Fan, S., Meng, Q., Rih, J. K., Kim, H. J., Kang, H. J., Xu, J., Goldberg, I. D., Jaiswal, A. K., and Rosen, E. M. (2004) Cancer Res. 64, 7893-7909). In the present study, we have investigated the effects of BRCA1 on xenobiotic stress-inducible gene expression. In response to aryl hydrocarbon receptor (AhR) ligands, cytoplasmic AhR becomes activated and then translocates to the nucleus where it forms a complex with the aryl hydrocarbon receptor nuclear translocator (ARNT). Subsequently, the AhR.ARNT complex binds to the enhancer or promoter of genes containing a xenobiotic stress-responsive element and regulates the expression of multiple target genes including cytochrome P450 subfamily polypeptide 1 (CYP1A1). In this study, we have found that endogenous and overexpressed exogenous wild-type BRCA1 affect xenobiotic stress-induced CYP1A1 gene expression. Using a standard chromatin immunoprecipitation assay, we have demonstrated that BRCA1 is recruited to the promoter regions of CYP1A1 and CYP1B1 along with ARNT and/or AhR following xenobiotic exposure. Our findings suggest that BRCA1 may be physiologically important for mounting a normal response to xenobiotic insults and that it may function as a coactivator for ARNT activity. Using immunoprecipitation, Western blotting, and glutathione S-transferase capture assays, a xenobiotic-independent interaction between BRCA1 and ARNT has been identified, although it is not yet known whether this is a direct or indirect interaction. We have also found that the inducibility of CYP1A1 and CYP1B1 transcripts following xenobiotic stress was significantly attenuated in BRCA1 knockdown cells. This reduced inducibility is associated with an altered stability of ARNT and was almost completely reversed in cells transfected with an ARNT expression vector. Finally, we have found that xenobiotic (TCDD) treatments of breast cancer cells containing reduced levels of BRCA1 cause the transcription factor ARNT to become unstable.
Collapse
Affiliation(s)
- Hyo Jin Kang
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, Washington, DC 20057, USA
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Chi H, Lu B, Takekawa M, Davis RJ, Flavell RA. GADD45beta/GADD45gamma and MEKK4 comprise a genetic pathway mediating STAT4-independent IFNgamma production in T cells. EMBO J 2004; 23:1576-86. [PMID: 15044949 PMCID: PMC391077 DOI: 10.1038/sj.emboj.7600173] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2003] [Accepted: 02/23/2004] [Indexed: 02/08/2023] Open
Abstract
The stress-inducible molecules GADD45beta and GADD45gamma have been implicated in regulating IFNgamma production in CD4 T cells. However, how GADD45 proteins function has been controversial. MEKK4 is a MAP kinase kinase kinase that interacts with GADD45 in vitro. Here we generated MEKK4-deficient mice to define the function and regulation of this pathway. CD4 T cells from MEKK4-/- mice have reduced p38 activity and defective IFNgamma synthesis. Expression of GADD45beta or GADD45gamma promotes IFNgamma production in MEKK4+/+ T cells, but not in MEKK4-/- cells or in cells treated with a p38 inhibitor. Thus, MEKK4 mediates the action of GADD45beta and GADD45gamma on p38 activation and IFNgamma production. During Th1 differentiation, the GADD45beta/GADD45gamma/MEKK4 pathway appears to integrate upstream signals transduced by both T cell receptor and IL12/STAT4, leading to augmented IFNgamma production in a process independent of STAT4.
Collapse
Affiliation(s)
- Hongbo Chi
- Section of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Binfeng Lu
- Section of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Mutsuhiro Takekawa
- Division of Molecular Cell Signaling, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- PRESTO, Japan Science and Technology Corporation (JST), Saitama, Japan
| | - Roger J Davis
- Howard Hughes Medical Institute and Program in Molecular Medicine, Department of Biochemistry & Molecular Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Richard A Flavell
- Section of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
- Howard Hughes Medical Institute, New Haven, CT, USA
| |
Collapse
|
39
|
Lu B, Ferrandino AF, Flavell RA. Gadd45beta is important for perpetuating cognate and inflammatory signals in T cells. Nat Immunol 2003; 5:38-44. [PMID: 14691480 DOI: 10.1038/ni1020] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Accepted: 11/05/2003] [Indexed: 12/22/2022]
Abstract
Gadd45beta (growth arrest and DNA damage-inducible, beta) is involved in cell cycle arrest, apoptosis, signal transduction and cell survival. In T cells, Gadd45b was rapidly induced by T cell receptor (TCR) and inflammatory signals. Deficiency of Gadd45beta in CD4+ T cells impaired their responses to TCR stimulation or inflammatory cytokines. ERK, p38 and JNK activation were all substantially suppressed in Gadd45beta-deficient CD4+ T cells. Cytokine production by Gadd45beta-deficient CD4+ T cells was also impaired. Furthermore, Gadd45beta mediated inflammatory cytokine production by dendritic cells, and Gadd45beta-deficient mice showed an impaired T helper type 1 response during Listeria monocytogenes infection. Gadd45beta is therefore a critical feedback regulator that perpetuates both cognate and inflammatory signals.
Collapse
Affiliation(s)
- Binfeng Lu
- Section of Immunobiology, Yale University School of Medicine, 310 Cedar Street, New Haven, Connecticut 06520-8011, USA
| | | | | |
Collapse
|
40
|
Chung HK, Yi YW, Jung NC, Kim D, Suh JM, Kim H, Park KC, Song JH, Kim DW, Hwang ES, Yoon SH, Bae YS, Kim JM, Bae I, Shong M. CR6-interacting factor 1 interacts with Gadd45 family proteins and modulates the cell cycle. J Biol Chem 2003; 278:28079-88. [PMID: 12716909 DOI: 10.1074/jbc.m212835200] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The Gadd45 family of proteins includes Gadd45alpha, MyD118/Gadd45beta, and CR6/OIG37/Gadd45gamma. These proteins play important roles in maintaining genomic stability and in regulating the cell cycle. This study reports the cloning of a novel protein called CR6-interacting factor 1 (CRIF1) which interacts with Gadd45alpha, MyD118/Gadd45beta, and CR6/OIG37/Gadd45gamma. CRIF1 binds specifically to the Gadd45 family proteins, as determined by an in vitro glutathione S-transferase pull-down assay and an in vivo mammalian cell two-hybrid assay along with coimmunoprecipitation assays. CRIF1 mRNA is highly expressed in the thyroid gland, heart, lymph nodes, trachea, and adrenal tissues. CRIF1 localizes exclusively to the nucleus and colocalizes with Gadd45gamma. Recombinant CRIF1 inhibits the histone H1 kinase activity of immunoprecipitated Cdc2-cyclin B1 and Cdk2-cyclin E, and the inhibitory effects were additive with Gadd45 proteins. Overexpression of CRIF1 increases the percentage of cells in G1, decreases the percentage of cells in S phase, and suppresses growth in NIH3T3 cells. The down-regulation of endogenous CRIF1 by the transfection of the small interfering RNA duplexes resulted in the inactivation of Rb by phosphorylation and decreased the G1 phase cell populations. Expression of CRIF1 is barely detectable in adrenal adenoma and papillary thyroid cancer and much lower than in adjacent normal tissue. The results presented here suggest that CRIF1 is a novel nuclear protein that interacts with Gadd45 and may play a role in negative regulation of cell cycle progression and cell growth.
Collapse
Affiliation(s)
- Hyo Kyun Chung
- Laboratory of Endocrine Cell Biology, National Research Laboratory Program, Chungnam National University School of Medicine, Daejeon 301-721 Korea
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Han C, Demetris AJ, Michalopoulos GK, Zhan Q, Shelhamer JH, Wu T. PPARgamma ligands inhibit cholangiocarcinoma cell growth through p53-dependent GADD45 and p21 pathway. Hepatology 2003; 38:167-77. [PMID: 12829999 DOI: 10.1053/jhep.2003.50296] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ligands of peroxisome proliferator-activated receptor-gamma (PPARgamma) induce differentiation and growth inhibition in several human cancers. However, the role of PPARgamma ligands in the growth control of human cholangiocarcinoma cells remains unknown. This study was designed to investigate the biological functions and molecular mechanisms of PPARgamma ligands in the growth regulation of human cholangiocarcinoma cells. Western blot analysis showed that PPARgamma is expressed in all of the three human cholangiocarcinoma cell lines used in this study (SG231, CC-LP-1, and HuCCT1). Transient transfection assays using a peroxisome proliferator response element (PPRE) reporter construct showed that the PPARgamma expressed in human cholangiocarcinoma cells is functional as a transcription activator. Exposure of SG231, CC-LP-1, and HuCCT1 cells to PPARgamma ligands 15-deoxy-delta12, 14-prostaglandin J(2) (15d-PGJ(2)) and troglitazone for 24 to 96 hours resulted in a dose-dependent inhibition of cell growth. Flow cytometry analysis showed that 15d-PGJ(2) and troglitazone-induced cell cycle arrest at the G2/M checkpoint. Consistent with these findings, both 15d-PGJ(2) and troglitazone significantly inhibited the G2/M cyclin-dependent kinase (CDK) Cdc2 activity. Furthermore, cells treated with 15d-PGJ(2) and troglitazone showed elevated expression of p53 and two p53-controlled downstream genes, GADD45 and p21(WAF1/Cip1). Dominant negative inhibition of p53 in SG231 cells significantly blocked the 15d-PGJ(2) and troglitazone-induced growth inhibition, G2/M arrest, and GADD45/p21 induction. 15d-PGJ(2) and troglitazone failed to directly inhibit Cdc2 activity in a cell-free system in spite of direct association between GADD45 and PPARgamma proteins. In conclusion, these results show a novel p53-dependent mechanism in the PPARgamma ligand-mediated inhibition of cholangiocarcinoma growth and suggest a potential therapeutic role of PPARgamma ligands in the treatment of human cholangiocarcinoma.
Collapse
Affiliation(s)
- Chang Han
- Department of Pathology, Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | | | | | | | | | | |
Collapse
|
42
|
Abstract
Cutaneous malignant melanoma (CMM) is a life-threatening cancer that can have a poor prognosis with high metastatic potential. Its incidence is rapidly increasing worldwide. Its molecular alterations involve multiple pathways, including those related to p53. Since 1981, more than 380 papers containing the terms 'p53 and melanoma' as key words in the Abstract have been published in the literature. However, in spite of these extensive investigations, a review of p53 and associated genes in CMM is still lacking. To remedy this issue, this review seeks to provide a brief overview of p53 and discuss the genes targeted along its related pathways.
Collapse
Affiliation(s)
- M R Hussein
- Department of Pathology, Faculty of Medicine, Assuit Univeristy, Assuit, Egypt
| | | | | |
Collapse
|
43
|
Abstract
Lipids and lipid metabolism have well-documented regulatory effects on inflammatory processes. Recent work has highlighted the role of the peroxisome proliferator-activated receptors (PPARs)--a subset of the nuclear-hormone-receptor superfamily that are activated by various lipid species--in regulating inflammatory responses. Here, we describe how the PPARs, through their interactions with transcription factors and other cell-signalling systems, have important regulatory roles in innate and adaptive immunity.
Collapse
Affiliation(s)
- Raymond A Daynes
- Department of Pathology, University of Utah School of Medicine, 30 North 1900 East, Salt Lake City, Utah 84132-2501, USA.
| | | |
Collapse
|
44
|
Lu B, Yu H, Chow C, Li B, Zheng W, Davis RJ, Flavell RA. GADD45gamma mediates the activation of the p38 and JNK MAP kinase pathways and cytokine production in effector TH1 cells. Immunity 2001; 14:583-90. [PMID: 11371360 DOI: 10.1016/s1074-7613(01)00141-8] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The p38 and JNK stress-activated MAPK signal transduction pathways are activated by T cell receptor (TCR) signaling and are required for IFN-gamma production by TH1 effector cells. Here, we show that the expression of GADD45gamma is induced during T cell activation and that the level of expression is higher in TH1 cells than in TH2 cells. TH1 cells from GADD45gamma(-/-) mice are severely compromised in their abilities to activate p38 and JNK in response to TCR signaling, produce much less IFN-gamma upon restimulation, and are deficient in activation-induced cell death (AICD). Additionally, GADD45gamma deficiencies caused reduced contact hypersensitivity in mice. Thus, GADD45gamma mediates activation of the p38 and JNK pathways and effector function of TH1 cells.
Collapse
Affiliation(s)
- B Lu
- Section of Immunobiology and, Yale University School of Medicine, 310 Cedar Street, New Haven, CT 06520, USA
| | | | | | | | | | | | | |
Collapse
|