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Adams JW, Vinokur A, de Souza JS, Austria C, Guerra BS, Herai RH, Wahlin KJ, Muotri AR. Loss of GTF2I promotes neuronal apoptosis and synaptic reduction in human cellular models of neurodevelopment. Cell Rep 2024; 43:113867. [PMID: 38416640 PMCID: PMC11002531 DOI: 10.1016/j.celrep.2024.113867] [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: 09/05/2023] [Revised: 01/04/2024] [Accepted: 02/09/2024] [Indexed: 03/01/2024] Open
Abstract
Individuals with Williams syndrome (WS), a neurodevelopmental disorder caused by hemizygous loss of 26-28 genes at 7q11.23, characteristically portray a hypersocial phenotype. Copy-number variations and mutations in one of these genes, GTF2I, are associated with altered sociality and are proposed to underlie hypersociality in WS. However, the contribution of GTF2I to human neurodevelopment remains poorly understood. Here, human cellular models of neurodevelopment, including neural progenitors, neurons, and three-dimensional cortical organoids, are differentiated from CRISPR-Cas9-edited GTF2I-knockout (GTF2I-KO) pluripotent stem cells to investigate the role of GTF2I in human neurodevelopment. GTF2I-KO progenitors exhibit increased proliferation and cell-cycle alterations. Cortical organoids and neurons demonstrate increased cell death and synaptic dysregulation, including synaptic structural dysfunction and decreased electrophysiological activity on a multielectrode array. Our findings suggest that changes in synaptic circuit integrity may be a prominent mediator of the link between alterations in GTF2I and variation in the phenotypic expression of human sociality.
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Affiliation(s)
- Jason W Adams
- Department of Pediatrics/Rady Children's Hospital, Department of Cellular & Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92037, USA; Department of Neurosciences, University of California, San Diego School of Medicine, La Jolla, CA 92093, USA; Center for Academic Research and Training in Anthropogeny, University of California, San Diego, La Jolla, CA 92093, USA
| | - Annabelle Vinokur
- Department of Pediatrics/Rady Children's Hospital, Department of Cellular & Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92037, USA
| | - Janaína S de Souza
- Department of Pediatrics/Rady Children's Hospital, Department of Cellular & Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92037, USA
| | - Charles Austria
- Department of Pediatrics/Rady Children's Hospital, Department of Cellular & Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92037, USA
| | - Bruno S Guerra
- Department of Pediatrics/Rady Children's Hospital, Department of Cellular & Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92037, USA; Experimental Multiuser Laboratory, Pontifícia Universidade Católica do Paraná, Curitiba, PR 80215-901, Brazil
| | - Roberto H Herai
- Department of Pediatrics/Rady Children's Hospital, Department of Cellular & Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92037, USA; Experimental Multiuser Laboratory, Pontifícia Universidade Católica do Paraná, Curitiba, PR 80215-901, Brazil
| | - Karl J Wahlin
- Shiley Eye Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Alysson R Muotri
- Department of Pediatrics/Rady Children's Hospital, Department of Cellular & Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92037, USA; Center for Academic Research and Training in Anthropogeny, University of California, San Diego, La Jolla, CA 92093, USA.
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Nir Sade A, Levy G, Schokoroy Trangle S, Elad Sfadia G, Bar E, Ophir O, Fischer I, Rokach M, Atzmon A, Parnas H, Rosenberg T, Marco A, Elroy Stein O, Barak B. Neuronal Gtf2i deletion alters mitochondrial and autophagic properties. Commun Biol 2023; 6:1269. [PMID: 38097729 PMCID: PMC10721858 DOI: 10.1038/s42003-023-05612-5] [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: 01/10/2023] [Accepted: 11/20/2023] [Indexed: 12/17/2023] Open
Abstract
Gtf2i encodes the general transcription factor II-I (TFII-I), with peak expression during pre-natal and early post-natal brain development stages. Because these stages are critical for proper brain development, we studied at the single-cell level the consequences of Gtf2i's deletion from excitatory neurons, specifically on mitochondria. Here we show that Gtf2i's deletion resulted in abnormal morphology, disrupted mRNA related to mitochondrial fission and fusion, and altered autophagy/mitophagy protein expression. These changes align with elevated reactive oxygen species levels, illuminating Gtf2i's importance in neurons mitochondrial function. Similar mitochondrial issues were demonstrated by Gtf2i heterozygous model, mirroring the human condition in Williams syndrome (WS), and by hemizygous neuronal Gtf2i deletion model, indicating Gtf2i's dosage-sensitive role in mitochondrial regulation. Clinically relevant, we observed altered transcript levels related to mitochondria, hypoxia, and autophagy in frontal cortex tissue from WS individuals. Our study reveals mitochondrial and autophagy-related deficits shedding light on WS and other Gtf2i-related disorders.
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Affiliation(s)
- Ariel Nir Sade
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Gilad Levy
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Sari Schokoroy Trangle
- The School of Psychological Sciences, Faculty of Social Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Galit Elad Sfadia
- The School of Psychological Sciences, Faculty of Social Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Ela Bar
- The School of Psychological Sciences, Faculty of Social Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Omer Ophir
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Inbar Fischer
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - May Rokach
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Andrea Atzmon
- The Shmunis School of Biomedicine & Cancer Research, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Hadar Parnas
- Neuro-Epigenetics Laboratory, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Tali Rosenberg
- Neuro-Epigenetics Laboratory, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Asaf Marco
- Neuro-Epigenetics Laboratory, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Orna Elroy Stein
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- The Shmunis School of Biomedicine & Cancer Research, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Boaz Barak
- The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
- The School of Psychological Sciences, Faculty of Social Sciences, Tel Aviv University, Tel Aviv, Israel.
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Voulgaridou GP, Theologidis V, Xanthis V, Papagiannaki E, Tsochantaridis I, Fadouloglou VE, Pappa A. Identification of a peptide ligand for human ALDH3A1 through peptide phage display: Prediction and characterization of protein interaction sites and inhibition of ALDH3A1 enzymatic activity. Front Mol Biosci 2023; 10:1161111. [PMID: 37021113 PMCID: PMC10067601 DOI: 10.3389/fmolb.2023.1161111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 03/07/2023] [Indexed: 04/07/2023] Open
Abstract
Aldehyde dehydrogenase 3A1 (ALDH3A1) by oxidizing medium chain aldehydes to their corresponding carboxylic acids, is involved in the detoxification of toxic byproducts and is considered to play an important role in antioxidant cellular defense. ALDH3A1 has been implicated in various other functions such as cell proliferation, cell cycle regulation, and DNA damage response. Recently, it has been identified as a putative biomarker of prostate, gastric, and lung cancer stem cell phenotype. Although ALDH3A1 has multifaceted functions in both normal and cancer homeostasis, its modes of action are currently unknown. To this end, we utilized a random 12-mer peptide phage display library to identify efficiently human ALDH3A1-interacting peptides. One prevailing peptide (P1) was systematically demonstrated to interact with the protein of interest, which was further validated in vitro by peptide ELISA. Bioinformatic analysis indicated two putative P1 binding sites on the protein surface implying biomedical potential and potent inhibitory activity of the P1 peptide on hALDH3A1 activity was demonstrated by enzymatic studies. Furthermore, in search of potential hALDH3A1 interacting players, a BLASTp search demonstrated that no protein in the database includes the full-length amino acid sequence of P1, but identified a list of proteins containing parts of the P1 sequence, which may prove potential hALDH3A1 interacting partners. Among them, Protein Kinase C Binding Protein 1 and General Transcription Factor II-I are candidates of high interest due to their cellular localization and function. To conclude, this study identifies a novel peptide with potential biomedical applications and further suggests a list of protein candidates be explored as possible hALDH3A1-interacting partners in future studies.
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Affiliation(s)
| | | | | | | | | | | | - Aglaia Pappa
- *Correspondence: Vasiliki E. Fadouloglou, ; Aglaia Pappa,
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Roy AL. Role of the multifunctional transcription factor TFII-I in DNA damage repair. DNA Repair (Amst) 2021; 106:103175. [PMID: 34280590 DOI: 10.1016/j.dnarep.2021.103175] [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: 05/27/2021] [Accepted: 07/07/2021] [Indexed: 11/27/2022]
Abstract
The multifunctional transcription factor TFII-I, encoded by the GTF2I gene, is implicated in various biological pathways, and associated with multiple human disorders. Evidence is also mounting to suggest that TFII-I is involved in DNA damage repair pathways. Here I bring together these recent observations and suggest a connection between transcriptional and DNA repair functions of TFII-I.
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Affiliation(s)
- Ananda L Roy
- National Institutes of Health, Laboratory of Molecular Biology and Immunology, Biomedical Research Center, National Institute on Aging, Baltimore, MD, United States.
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Kozel BA, Barak B, Ae Kim C, Mervis CB, Osborne LR, Porter M, Pober BR. Williams syndrome. Nat Rev Dis Primers 2021; 7:42. [PMID: 34140529 PMCID: PMC9437774 DOI: 10.1038/s41572-021-00276-z] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/13/2021] [Indexed: 11/09/2022]
Abstract
Williams syndrome (WS) is a relatively rare microdeletion disorder that occurs in as many as 1:7,500 individuals. WS arises due to the mispairing of low-copy DNA repetitive elements at meiosis. The deletion size is similar across most individuals with WS and leads to the loss of one copy of 25-27 genes on chromosome 7q11.23. The resulting unique disorder affects multiple systems, with cardinal features including but not limited to cardiovascular disease (characteristically stenosis of the great arteries and most notably supravalvar aortic stenosis), a distinctive craniofacial appearance, and a specific cognitive and behavioural profile that includes intellectual disability and hypersociability. Genotype-phenotype evidence is strongest for ELN, the gene encoding elastin, which is responsible for the vascular and connective tissue features of WS, and for the transcription factor genes GTF2I and GTF2IRD1, which are known to affect intellectual ability, social functioning and anxiety. Mounting evidence also ascribes phenotypic consequences to the deletion of BAZ1B, LIMK1, STX1A and MLXIPL, but more work is needed to understand the mechanism by which these deletions contribute to clinical outcomes. The age of diagnosis has fallen in regions of the world where technological advances, such as chromosomal microarray, enable clinicians to make the diagnosis of WS without formally suspecting it, allowing earlier intervention by medical and developmental specialists. Phenotypic variability is considerable for all cardinal features of WS but the specific sources of this variability remain unknown. Further investigation to identify the factors responsible for these differences may lead to mechanism-based rather than symptom-based therapies and should therefore be a high research priority.
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Affiliation(s)
- Beth A. Kozel
- Translational Vascular Medicine Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, USA
| | - Boaz Barak
- The Sagol School of Neuroscience and The School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Chong Ae Kim
- Department of Pediatrics, Universidade de São Paulo, São Paulo, Brazil
| | - Carolyn B. Mervis
- Department of Psychological and Brain Sciences, University of Louisville, Louisville, USA
| | - Lucy R. Osborne
- Department of Medicine, University of Toronto, Ontario, Canada
| | - Melanie Porter
- Department of Psychology, Macquarie University, Sydney, Australia
| | - Barbara R. Pober
- Department of Pediatrics, Massachusetts General Hospital and Harvard Medical School, Boston, USA
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Linzer N, Trumbull A, Nar R, Gibbons MD, Yu DT, Strouboulis J, Bungert J. Regulation of RNA Polymerase II Transcription Initiation and Elongation by Transcription Factor TFII-I. Front Mol Biosci 2021; 8:681550. [PMID: 34055891 PMCID: PMC8155576 DOI: 10.3389/fmolb.2021.681550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 04/20/2021] [Indexed: 11/13/2022] Open
Abstract
Transcription by RNA polymerase II (Pol II) is regulated by different processes, including alterations in chromatin structure, interactions between distal regulatory elements and promoters, formation of transcription domains enriched for Pol II and co-regulators, and mechanisms involved in the initiation, elongation, and termination steps of transcription. Transcription factor TFII-I, originally identified as an initiator (INR)-binding protein, contains multiple protein–protein interaction domains and plays diverse roles in the regulation of transcription. Genome-wide analysis revealed that TFII-I associates with expressed as well as repressed genes. Consistently, TFII-I interacts with co-regulators that either positively or negatively regulate the transcription. Furthermore, TFII-I has been shown to regulate transcription pausing by interacting with proteins that promote or inhibit the elongation step of transcription. Changes in TFII-I expression in humans are associated with neurological and immunological diseases as well as cancer. Furthermore, TFII-I is essential for the development of mice and represents a barrier for the induction of pluripotency. Here, we review the known functions of TFII-I related to the regulation of Pol II transcription at the stages of initiation and elongation.
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Affiliation(s)
- Niko Linzer
- Department of Biochemistry and Molecular Biology, College of Medicine, UF Health Cancer Center, Genetics Institute, Powell Gene Therapy Center, University of Florida, Gainesville, FL, United States
| | - Alexis Trumbull
- Department of Biochemistry and Molecular Biology, College of Medicine, UF Health Cancer Center, Genetics Institute, Powell Gene Therapy Center, University of Florida, Gainesville, FL, United States
| | - Rukiye Nar
- Department of Biochemistry and Molecular Biology, College of Medicine, UF Health Cancer Center, Genetics Institute, Powell Gene Therapy Center, University of Florida, Gainesville, FL, United States
| | - Matthew D Gibbons
- Department of Biochemistry and Molecular Biology, College of Medicine, UF Health Cancer Center, Genetics Institute, Powell Gene Therapy Center, University of Florida, Gainesville, FL, United States
| | - David T Yu
- Department of Biochemistry and Molecular Biology, College of Medicine, UF Health Cancer Center, Genetics Institute, Powell Gene Therapy Center, University of Florida, Gainesville, FL, United States
| | - John Strouboulis
- Comprehensive Cancer Center, School of Cancer and Pharmaceutical Sciences, King's College London, United Kingdom
| | - Jörg Bungert
- Department of Biochemistry and Molecular Biology, College of Medicine, UF Health Cancer Center, Genetics Institute, Powell Gene Therapy Center, University of Florida, Gainesville, FL, United States
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Shen Y, Nar R, Fan AX, Aryan M, Hossain MA, Gurumurthy A, Wassel PC, Tang M, Lu J, Strouboulis J, Bungert J. Functional interrelationship between TFII-I and E2F transcription factors at specific cell cycle gene loci. J Cell Biochem 2017; 119:712-722. [PMID: 28657656 DOI: 10.1002/jcb.26235] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 06/22/2017] [Indexed: 11/10/2022]
Abstract
Transcription factor TFII-I is a multifunctional protein implicated in the regulation of cell cycle and stress-response genes. Previous studies have shown that a subset of TFII-I associated genomic sites contained DNA-binding motifs for E2F family transcription factors. We analyzed the co-association of TFII-I and E2Fs in more detail using bioinformatics, chromatin immunoprecipitation, and co-immunoprecipitation experiments. The data show that TFII-I interacts with E2F transcription factors. Furthermore, TFII-I, E2F4, and E2F6 interact with DNA-regulatory elements of several genes implicated in the regulation of the cell cycle, including DNMT1, HDAC1, CDKN1C, and CDC27. Inhibition of TFII-I expression led to a decrease in gene expression and in the association of E2F4 and E2F6 with these gene loci in human erythroleukemia K562 cells. Finally, TFII-I deficiency reduced the proliferation of K562 cells and increased the sensitivity toward doxorubicin toxicity. The results uncover novel interactions between TFII-I and E2Fs and suggest that TFII-I mediates E2F function at specific cell cycle genes.
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Affiliation(s)
- Yong Shen
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Rukiye Nar
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Alex X Fan
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Mahmoud Aryan
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Mir A Hossain
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Aishwarya Gurumurthy
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Paul C Wassel
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Ming Tang
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - Jianrong Lu
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
| | - John Strouboulis
- Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology-Hellas, Heraklion, Crete, Greece
| | - Jörg Bungert
- Department of Biochemistry and Molecular Biology, Center for Epigenetics, Genetics Institute, Health Cancer Center, Powell-Gene Therapy Center, University of Florida, Gainesville, Florida
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Feng Y, Lei Y, Wu X, Huang Y, Rao H, Zhang Y, Wang F. GTF2I mutation frequently occurs in more indolent thymic epithelial tumors and predicts better prognosis. Lung Cancer 2017; 110:48-52. [PMID: 28676218 DOI: 10.1016/j.lungcan.2017.05.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 05/11/2017] [Accepted: 05/23/2017] [Indexed: 01/15/2023]
Abstract
OBJECTIVES A missense mutation in GTF2I was previously identified in thymic epithelioid tumor (TET). However, the clinicopathological relevance of GTF2I mutation has not been illustrated. We studied the prognostic importance of GTF2I mutation as well as its relation to histological subtypes in a large number of TETs. METHODS TET samples from 296 patients with clinical and follow-up data were collected, and histological subtypes were classified. Analysis of the GTF2I (chromosome 7 c.74146970T>A) mutation was undertaken by using quantitative real time polymerase chain reaction (qPCR) and direct sequencing. The association of GTF2I mutation with clinicopathological features as well as prognosis was analyzed. RESULTS One hundred twenty-four out of 296 (41.9%) patients harbored the GTF2I mutation (chromosome 7 c.74146970T>A). GTF2I mutation was observed in 20 (87.0%) cases of type A thymoma, 70 (78.7%) of type AB thymoma, and the frequency decreased with the degree of histological subtype aggressiveness, with the lowest rate in thymic carcinoma (7.7%). The difference of GTF2I mutation distribution in histological subtypes was statistically significant (p<0.001). The GTF2I mutation was found more frequently in patients with early Masaoka stage (I-II, n=112, 90.3%) than in those with advanced stage (III-IV) disease (n=12, 9.6%, p<0.001). However, only histological subtype significantly predicted the presence of the GTF2I mutation in patients with TETs. The presence of the GTF2I mutation correlated with better prognosis (90.0% compared to 72.0% 5-year survival, and 86% compared to 56% 10-year survival, respectively; log-rank p=0.001). Moreover, it was an independent prognostic factor [hazard ratio (HR), 0.35; 95% confidential interval (CI), 0.15-0.81; p=0.014)]. CONCLUSIONS The frequency of the GTF2I mutation is higher in more indolent TETs, and correlates with better prognosis. Further studies are required to elucidate the role of the GTF2I mutation in TETs and its clinical application.
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Affiliation(s)
- Yanfen Feng
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, PR China; Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, PR China.
| | - Yiyan Lei
- Department of Thoracic Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong 510060, PR China.
| | - Xiaoyan Wu
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, PR China; Department of Molecular Diagnostics, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong 510060, PR China.
| | - Yuhua Huang
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, PR China; Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, PR China.
| | - Huilan Rao
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, PR China; Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, PR China.
| | - Yu Zhang
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, PR China; Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, PR China.
| | - Fang Wang
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, PR China; Department of Molecular Diagnostics, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong 510060, PR China.
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9
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Roy AL. Pathophysiology of TFII-I: Old Guard Wearing New Hats. Trends Mol Med 2017; 23:501-511. [PMID: 28461154 DOI: 10.1016/j.molmed.2017.04.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/30/2017] [Accepted: 04/05/2017] [Indexed: 12/23/2022]
Abstract
The biochemical properties of the signal-induced multifunctional transcription factor II-I (TFII-I) indicate that it is involved in a variety of gene regulatory processes. Although gene ablation in murine models and cell-based assays show that it is encoded by an essential gene, GTF2I/Gtf2i, its physiologic role in human disorders was relatively unknown until recently. Novel studies show that it is involved in an array of human diseases including neurocognitive disorders, systemic lupus erythematosus (SLE), and cancer. Here I bring together these diverse observations to illustrate its multiple pathophysiologic functions and further conjecture on how these could be related to its known biochemical properties. I expect that a better understanding of these 'structure-function' relationships would lead to future diagnostic and/or therapeutic potential.
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Affiliation(s)
- Ananda L Roy
- Laboratory of Molecular Biology and Immunology, Biomedical Research Center, National Institutes of Health/National Institute on Aging, 251 Bayview Blvd, Baltimore, MD 21224, USA.
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10
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Guenat D, Merla G, Deconinck E, Borg C, Rohrlich PS. DNA damage response defect in Williams-Beuren syndrome. Int J Mol Med 2017; 39:622-628. [PMID: 28098859 PMCID: PMC5360356 DOI: 10.3892/ijmm.2017.2861] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 12/29/2016] [Indexed: 11/19/2022] Open
Abstract
Williams-Beuren syndrome (WBS, no. OMIM 194050) is a rare multisystem genetic disorder caused by a microdeletion on chromosome 7q11.23 and characterized by cardiovascular malformations, mental retardation, and a specific facial dysmorphism. Recently, we reported that a series of non-Hodgkin's lymphoma occurs in children with WBS and thus hypothesized that a predisposition to cancer may be associated with this genetic disorder. The aim of the present study was to ascertain the role played by three genes hemizygously deleted in WBS (RFC2, GTF2I and BAZ1B) in DNA damage response pathways. Cell proliferation, cell cycle analysis, γ-H2A.X induction, and expression of DNA damage response proteins were investigated upon exposure to genotoxic treatments in WBS patient-derived primary fibroblasts and in the 293T cell line treated with specific siRNAs targeting RFC2, GTF2I and BAZ1B. An impaired hydroxyurea-induced phosphorylation of CHK1 was observed in the WBS cells. However, this defective DNA damage response was not associated with an increased sensitivity to genotoxic agents. In addition, depletion of RFC2, GTF2I and BAZ1B using specific siRNAs did not have a significant impact on the DNA damage response in 293T cells. Our results highlight that the ATR-dependent DNA damage response is impaired in WBS patient cells but is also dispensable for viability when these cells undergo a genotoxic stress. The mechanism by which the ATR pathway is impaired in WBS warrants elucidation through further investigation.
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Affiliation(s)
- David Guenat
- Laboratory of Cellular and Molecular Biology, University Hospital of Besançon, F-25000 Besançon, France
| | - Giuseppe Merla
- Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia I‑71013, Italy
| | - Eric Deconinck
- Inserm UMR1098/EFS‑BFC/University of Franche‑Comte, LabEx LipSTIC, F-25000 Besançon, France
| | - Christophe Borg
- Inserm UMR1098/EFS‑BFC/University of Franche‑Comte, LabEx LipSTIC, F-25000 Besançon, France
| | - Pierre-Simon Rohrlich
- Inserm UMR1098/EFS‑BFC/University of Franche‑Comte, LabEx LipSTIC, F-25000 Besançon, France
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The Adenovirus E4-ORF3 Protein Stimulates SUMOylation of General Transcription Factor TFII-I to Direct Proteasomal Degradation. mBio 2016; 7:e02184-15. [PMID: 26814176 PMCID: PMC4742714 DOI: 10.1128/mbio.02184-15] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
UNLABELLED Modulation of host cell transcription, translation, and posttranslational modification processes is critical for the ability of many viruses to replicate efficiently within host cells. The human adenovirus (Ad) early region 4 open reading frame 3 (E4-ORF3) protein forms unique inclusions throughout the nuclei of infected cells and inhibits the antiviral Mre11-Rad50-Nbs1 DNA repair complex through relocalization. E4-ORF3 also induces SUMOylation of Mre11 and Nbs1. We recently identified additional cellular targets of E4-ORF3 and found that E4-ORF3 stimulates ubiquitin-like modification of 41 cellular proteins involved in a wide variety of processes. Among the proteins most abundantly modified in an E4-ORF3-dependent manner was the general transcription factor II-I (TFII-I). Analysis of Ad-infected cells revealed that E4-ORF3 induces TFII-I relocalization and SUMOylation early during infection. In the present study, we explored the relationship between E4-ORF3 and TFII-I. We found that Ad infection or ectopic E4-ORF3 expression leads to SUMOylation of TFII-I that precedes a rapid decline in TFII-I protein levels. We also show that E4-ORF3 is required for ubiquitination of TFII-I and subsequent proteasomal degradation. This is the first evidence that E4-ORF3 regulates ubiquitination. Interestingly, we found that E4-ORF3 modulation of TFII-I occurs in diverse cell types but only E4-ORF3 of Ad species C regulates TFII-I, providing critical insight into the mechanism by which E4-ORF3 targets TFII-I. Finally, we show that E4-ORF3 stimulates the activity of a TFII-I-repressed viral promoter during infection. Our results characterize a novel mechanism of TFII-I regulation by Ad and highlight how a viral protein can modulate a critical cellular transcription factor during infection. IMPORTANCE Adenovirus has evolved a number of mechanisms to target host signaling pathways in order to optimize the cellular environment during infection. E4-ORF3 is a small viral protein made early during infection, and it is critical for inactivating host antiviral responses. In addition to its ability to capture and reorganize cellular proteins, E4-ORF3 also regulates posttranslational modifications of target proteins, but little is known about the functional consequences of these modifications. We recently identified TFII-I as a novel target of E4-ORF3 that is relocalized into dynamic E4-ORF3 nuclear structures and subjected to E4-ORF3-mediated SUMO modification. Here, we show that TFII-I is targeted by E4-ORF3 for ubiquitination and proteasomal degradation and that E4-ORF3 stimulates gene expression from a TFII-I-repressed viral promoter. Our findings suggest that the specific targeting of TFII-I by E4-ORF3 is a mechanism to inactivate its antiviral properties. These studies provide further insight into how E4-ORF3 functions to counteract host antiviral responses.
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Cetkovská K, Šustová H, Kosztyu P, Uldrijan S. A Novel Interaction between TFII-I and Mdm2 with a Negative Effect on TFII-I Transcriptional Activity. PLoS One 2015; 10:e0144753. [PMID: 26656605 PMCID: PMC4676684 DOI: 10.1371/journal.pone.0144753] [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: 05/22/2015] [Accepted: 11/23/2015] [Indexed: 11/24/2022] Open
Abstract
Williams-Beuren syndrome-associated transcription factor TFII-I plays a critical regulatory role in bone and neural tissue development and in immunity, in part by regulating cell proliferation in response to mitogens. Mdm2, a cellular oncogene responsible for the loss of p53 tumor suppressor activity in a significant proportion of human cancers, was identified in this study as a new binding partner for TFII-I and a negative regulator of TFII-I-mediated transcription. These findings suggest a new p53-independent mechanism by which increased Mdm2 levels found in human tumors could influence cancer cells. In addition to that, we present data indicating that TFII-I is an important cellular regulator of transcription from the immediate-early promoter of human cytomegalovirus, a promoter sequence frequently used in mammalian expression vectors, including vectors for gene therapy. Our observation that Mdm2 over-expression can decrease the ability of TFII-I to activate the CMV promoter might have implications for the efficiency of experimental gene therapy based on CMV promoter–derived vectors in cancers with Mdm2 gene amplification.
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Affiliation(s)
- Kateřina Cetkovská
- International Clinical Research Center—Center of Biomolecular and Cellular Engineering, St. Anne's University Hospital, Brno, Czech Republic
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Hana Šustová
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Pavlína Kosztyu
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Stjepan Uldrijan
- International Clinical Research Center—Center of Biomolecular and Cellular Engineering, St. Anne's University Hospital, Brno, Czech Republic
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- * E-mail:
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Tu J, Chen Y, Cai L, Xu C, Zhang Y, Chen Y, Zhang C, Zhao J, Cheng J, Xie H, Zhong F, He F. Functional Proteomics Study Reveals SUMOylation of TFII-I is Involved in Liver Cancer Cell Proliferation. J Proteome Res 2015; 14:2385-97. [PMID: 25869096 DOI: 10.1021/acs.jproteome.5b00062] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
SUMOylation has emerged as a new regulatory mechanism for proteins involved in multiple physiological and pathological processes. However, the detailed function of SUMOylation in liver cancer is still elusive. This study reveals that the SUMOylation-activating enzyme UBA2 is highly expressed in liver cancer cells and clinical samples. Silencing of UBA2 expression could to some extent suppress cell proliferation. To elucidate the function of UBA2, we used a large scale proteomics strategy to identify SUMOylation targets in HepG2 cells. We characterized 827 potential SUMO1-modified proteins that were not present in the control samples. These proteins were enriched in gene expression processes. Twelve candidates were validated as SUMO1-modified proteins by immunoprecipitation-Western blotting. We further characterized SUMOylated protein TFII-I that was identified in this study and determined that TFII-I was modified by SUMO1 at K221 and K240. PIAS4 was an E3 ligase for TFII-I SUMOylation, and SENP2 was responsible for deSUMOylating TFII-I in HepG2 cells. SUMOylation reduced TFII-I binding to its repressor HDAC3 and thus promoted its transcriptional activity. We further show that SUMOylation is critical for TFII-I to promote cell proliferation and colony formation. Our findings contribute to understanding the role of SUMOylation in liver cancer development.
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Affiliation(s)
- Jun Tu
- †Department of Chemistry, Fudan University, Shanghai 200433, China.,‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Yalan Chen
- ∥Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Lili Cai
- ‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Changming Xu
- #College of Mechatronics and Automation, National University of Defense Technology, Changsha 410073, China
| | - Yang Zhang
- ‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.,§Department of Systems Biology for Medicine, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yanmei Chen
- ‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Chen Zhang
- ‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Jian Zhao
- ‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Jinke Cheng
- ∥Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hongwei Xie
- #College of Mechatronics and Automation, National University of Defense Technology, Changsha 410073, China
| | - Fan Zhong
- ‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.,§Department of Systems Biology for Medicine, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Fuchu He
- †Department of Chemistry, Fudan University, Shanghai 200433, China.,‡Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.,⊥State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences Beijing, Beijing Institute of Radiation Medicine, Beijing 102206, China
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Genome-wide targeting of the epigenetic regulatory protein CTCF to gene promoters by the transcription factor TFII-I. Proc Natl Acad Sci U S A 2015; 112:E677-86. [PMID: 25646466 DOI: 10.1073/pnas.1416674112] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
CCCTC-binding factor (CTCF) is a key regulator of nuclear chromatin structure and gene regulation. The impact of CTCF on transcriptional output is highly varied, ranging from repression to transcriptional pausing and transactivation. The multifunctional nature of CTCF may be directed solely through remodeling chromatin architecture. However, another hypothesis is that the multifunctional nature of CTCF is mediated, in part, through differential association with protein partners having unique functions. Consistent with this hypothesis, our mass spectrometry analyses of CTCF interacting partners reveal a previously undefined association with the transcription factor general transcription factor II-I (TFII-I). Biochemical fractionation of CTCF indicates that a distinct CTCF complex incorporating TFII-I is assembled on DNA. Unexpectedly, we found that the interaction between CTCF and TFII-I is essential for directing CTCF to the promoter proximal regulatory regions of target genes across the genome, particularly at genes involved in metabolism. At genes coregulated by CTCF and TFII-I, we find knockdown of TFII-I results in diminished CTCF binding, lack of cyclin-dependent kinase 8 (CDK8) recruitment, and an attenuation of RNA polymerase II phosphorylation at serine 5. Phenotypically, knockdown of TFII-I alters the cellular response to metabolic stress. Our data indicate that TFII-I directs CTCF binding to target genes, and in turn the two proteins cooperate to recruit CDK8 and enhance transcription initiation.
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Petrini I, Meltzer PS, Kim IK, Lucchi M, Park KS, Fontanini G, Gao J, Zucali PA, Calabrese F, Favaretto A, Rea F, Rodriguez-Canales J, Walker RL, Pineda M, Zhu YJ, Lau C, Killian KJ, Bilke S, Voeller D, Dakshanamurthy S, Wang Y, Giaccone G. A specific missense mutation in GTF2I occurs at high frequency in thymic epithelial tumors. Nat Genet 2014; 46:844-9. [PMID: 24974848 DOI: 10.1038/ng.3016] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 06/02/2014] [Indexed: 12/15/2022]
Abstract
We analyzed 28 thymic epithelial tumors (TETs) using next-generation sequencing and identified a missense mutation (chromosome 7 c.74146970T>A) in GTF2I at high frequency in type A thymomas, a relatively indolent subtype. In a series of 274 TETs, we detected the GTF2I mutation in 82% of type A and 74% of type AB thymomas but rarely in the aggressive subtypes, where recurrent mutations of known cancer genes have been identified. Therefore, GTF2I mutation correlated with better survival. GTF2I β and δ isoforms were expressed in TETs, and both mutant isoforms were able to stimulate cell proliferation in vitro. Thymic carcinomas carried a higher number of mutations than thymomas (average of 43.5 and 18.4, respectively). Notably, we identified recurrent mutations of known cancer genes, including TP53, CYLD, CDKN2A, BAP1 and PBRM1, in thymic carcinomas. These findings will complement the diagnostic assessment of these tumors and also facilitate development of a molecular classification and assessment of prognosis and treatment strategies.
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Affiliation(s)
- Iacopo Petrini
- Medical Oncology Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Paul S Meltzer
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - In-Kyu Kim
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
| | - Marco Lucchi
- Thoracic Surgery, Pisa University Hospital, Pisa, Italy
| | - Kang-Seo Park
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
| | | | - James Gao
- Medical Oncology Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Paolo A Zucali
- Medical Oncology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | | | | | - Federico Rea
- Thoracic Surgery, Padua University Hospital, Padua, Italy
| | | | - Robert L Walker
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Marbin Pineda
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Yuelin J Zhu
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Christopher Lau
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Keith J Killian
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Sven Bilke
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Donna Voeller
- Medical Oncology Branch, National Cancer Institute, Bethesda, Maryland, USA
| | | | - Yisong Wang
- 1] Medical Oncology Branch, National Cancer Institute, Bethesda, Maryland, USA. [2] Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
| | - Giuseppe Giaccone
- 1] Medical Oncology Branch, National Cancer Institute, Bethesda, Maryland, USA. [2] Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
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Role of multifunctional transcription factor TFII-I and putative tumour suppressor DBC1 in cell cycle and DNA double strand damage repair. Br J Cancer 2013; 109:3042-8. [PMID: 24231951 PMCID: PMC3859932 DOI: 10.1038/bjc.2013.532] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 08/09/2013] [Accepted: 08/13/2013] [Indexed: 01/01/2023] Open
Abstract
Background: In multicellular organisms, precise control of cell cycle and the maintenance of genomic stability are crucial to prevent chromosomal alterations. The accurate function of the DNA damage pathway is maintained by DNA repair mechanisms including homologous recombination (HR). Herein, we show that both TFII-I and DBC1 mediate cellular mechanisms of cell-cycle regulation and DNA double strand damage repair. Methods: Regulation of cell cycle by TFII-I and DBC1 was investigated using Trypan blue dye exclusion test, luciferase assay, and flow cytometry analysis. We also analysed the role of TFII-I and DBC1 in DNA double strand damage repair after irradiation by immunofluorescence study, clonogenicity assay, and HR assay. Results: Flow cytometry analysis revealed a novel function that siRNA-mediated knockdown of endogenous DBC1 resulted in G2/M phase arrest. We also have shown that both endogenous TFII-I and DBC1 activate DNA repair mechanisms after irradiation because irradiation-induced foci formation of TFII-I-γH2AX was observed, and the depletion of endogenous TFII-I or DBC1 resulted in the inhibition of normal HR efficiency. Conclusion: These results reveal novel mechanisms by which TFII-I and DBC1 can modulate cellular fate by affecting cell-cycle control as well as HR pathway.
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Roy AL. Biochemistry and biology of the inducible multifunctional transcription factor TFII-I: 10 years later. Gene 2011; 492:32-41. [PMID: 22037610 DOI: 10.1016/j.gene.2011.10.030] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 10/08/2011] [Accepted: 10/11/2011] [Indexed: 12/12/2022]
Abstract
Exactly twenty years ago TFII-I was discovered as a biochemical entity that was able to bind to and function via a core promoter element called the Initiator (Inr). Since then several different properties of this signal-induced multifunctional factor were discovered. Here I update these ever expanding functions of TFII-I--focusing primarily on the last ten years since the first review appeared in this journal.
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Affiliation(s)
- Ananda L Roy
- Department of Pathology, Sackler School of Biomedical Sciences, Tufts University School of Medicine, 150 Harrison Avenue, Boston, MA 02111, USA.
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Misra UK, Mowery YM, Gawdi G, Pizzo SV. Loss of cell surface TFII-I promotes apoptosis in prostate cancer cells stimulated with activated α₂ -macroglobulin. J Cell Biochem 2011; 112:1685-95. [PMID: 21503958 DOI: 10.1002/jcb.23083] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Receptor-recognized forms of α₂ -macroglobulin (α₂ M) bind to cell surface-associated GRP78 and initiate pro-proliferative and anti-apoptotic signaling. Ligation of GRP78 with α₂ M also upregulates TFII-I, which binds to the GRP78 promoter and enhances GRP78 synthesis. In addition to its transcriptional functions, cytosolic TFII-I regulates agonist-induced Ca(2+) entry. In this study we show that down regulation of TFII-I gene expression by RNAi profoundly impairs its cell surface expression and anti-apoptotic signaling as measured by significant reduction of GRP78, Bcl-2, and cyclin D1 in 1-Ln and DU-145 human prostate cancer cells stimulated with α₂ M. In contrast, this treatment significantly increases levels of the pro-apoptotic proteins p53, p27, Bax, and Bak and causes DNA fragmentation. Furthermore, down regulation of TFII-I expression activates agonist-induced Ca(2+) entry. In plasma membrane lysates p-PLCγ1, TRPC3, GRP78, MTJ1, and caveolin co-immunoprecipitate with TFII-I suggesting multimeric complexes of these proteins. Consistent with this hypothesis, down regulating TFII-I, MTJ1, or GRP78 expression by RNAi greatly attenuates cell surface expression of TFII-I. In conclusion, we demonstrate that not only does cell surface GRP78 regulate apoptosis, but it also regulates Ca(2+) homeostasis by controlling cell surface localization of TFII-I.
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Affiliation(s)
- U K Misra
- Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Fijalkowska I, Sharma D, Bult CJ, Danoff SK. Expression of the transcription factor, TFII-I, during post-implantation mouse embryonic development. BMC Res Notes 2010; 3:203. [PMID: 20642858 PMCID: PMC2921380 DOI: 10.1186/1756-0500-3-203] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Accepted: 07/20/2010] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND General transcription factor (TFII-I) is a multi-functional transcription factor encoded by the Gtf2i gene, that has been demonstrated to regulate transcription of genes critical for development. Because of the broad range of genes regulated by TFII-I as well as its potential role in a significant neuro-developmental disorder, developing a comprehensive expression profile is critical to the study of this transcription factor. We sought to define the timing and pattern of expression of TFII-I in post-implantation embryos at a time during which many putative TFII-I target genes are expressed. FINDINGS Antibodies to the N-terminus of TFII-I were used to probe embryonic mouse sections. TFII-I protein is widely expressed in the developing embryo. TFII-I is expressed throughout the period from E8-E16. However, within this period there are striking shifts in localization from cytoplasmic predominant to nuclear. TFII-I expression varies in both a spatial and temporal fashion. There is extensive expression in neural precursors at E8. This expression persists at later stages. TFII-I is expressed in developing lung, heart and gut structures. There is no evidence of isoform specific expression. Available data regarding expression patterns at both an RNA and protein level throughout development are also comprehensively reviewed. CONCLUSIONS Our immunohistochemical studies of the temporal and spatial expression patterns of TFII-I in mouse embryonic sections are consistent with the hypothesis that hemizygous deletion of GTF2I in individuals with Williams-Beuren Syndrome contributes to the distinct cognitive and physiological symptoms associated with the disorder.
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Affiliation(s)
- Iwona Fijalkowska
- Johns Hopkins University School of Medicine, Department of Medicine, Cardiopulmonary and Critical Care Division, 1830 E, Monument Street, Baltimore, MD 21205, USA.
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Lucena J, Pezzi S, Aso E, Valero MC, Carreiro C, Dubus P, Sampaio A, Segura M, Barthelemy I, Zindel MY, Sousa N, Barbero JL, Maldonado R, Pérez-Jurado LA, Campuzano V. Essential role of the N-terminal region of TFII-I in viability and behavior. BMC MEDICAL GENETICS 2010; 11:61. [PMID: 20403157 PMCID: PMC2865459 DOI: 10.1186/1471-2350-11-61] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Accepted: 04/19/2010] [Indexed: 01/02/2023]
Abstract
Background GTF2I codes for a general intrinsic transcription factor and calcium channel regulator TFII-I, with high and ubiquitous expression, and a strong candidate for involvement in the morphological and neuro-developmental anomalies of the Williams-Beuren syndrome (WBS). WBS is a genetic disorder due to a recurring deletion of about 1,55-1,83 Mb containing 25-28 genes in chromosome band 7q11.23 including GTF2I. Completed homozygous loss of either the Gtf2i or Gtf2ird1 function in mice provided additional evidence for the involvement of both genes in the craniofacial and cognitive phenotype. Unfortunately nothing is now about the behavioral characterization of heterozygous mice. Methods By gene targeting we have generated a mutant mice with a deletion of the first 140 amino-acids of TFII-I. mRNA and protein expression analysis were used to document the effect of the study deletion. We performed behavioral characterization of heterozygous mutant mice to document in vivo implications of TFII-I in the cognitive profile of WBS patients. Results Homozygous and heterozygous mutant mice exhibit craniofacial alterations, most clearly represented in homozygous condition. Behavioral test demonstrate that heterozygous mutant mice exhibit some neurobehavioral alterations and hyperacusis or odynacusis that could be associated with specific features of WBS phenotype. Homozygous mutant mice present highly compromised embryonic viability and fertility. Regarding cellular model, we documented a retarded growth in heterozygous MEFs respect to homozygous or wild-type MEFs. Conclusion Our data confirm that, although additive effects of haploinsufficiency at several genes may contribute to the full craniofacial or neurocognitive features of WBS, correct expression of GTF2I is one of the main players. In addition, these findings show that the deletion of the fist 140 amino-acids of TFII-I altered it correct function leading to a clear phenotype, at both levels, at the cellular model and at the in vivo model.
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Affiliation(s)
- Jaume Lucena
- Genetics Unit, de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, Spain
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Lazebnik MB, Tussie-Luna MI, Hinds PW, Roy AL. Williams-Beuren syndrome-associated transcription factor TFII-I regulates osteogenic marker genes. J Biol Chem 2009; 284:36234-36239. [PMID: 19880526 DOI: 10.1074/jbc.c109.063115] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Williams-Beuren syndrome (WBS), an autosomal dominant genetic disorder, is characterized by a unique cognitive profile and craniofacial defects. WBS results from a microdeletion at the chromosomal location 7q11.23 that encompasses the genes encoding the members of TFII-I family of transcription factors. Given that the haploinsufficiency for TFII-I is causative to the craniofacial phenotype in humans, we set out to analyze the effect of post-transcriptional silencing of TFII-I during BMP-2-driven osteoblast differentiation in the C2C12 cell line. Our results show that TFII-I plays an inhibitory role in regulating genes that are essential in osteogenesis and intersects with the bone-specific transcription factor Runx2 and the retinoblastoma protein, pRb. Identification of pathways regulated by TFII-I family transcription factors may begin to shed light on the molecular determinants of WBS.
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Affiliation(s)
- Maria B Lazebnik
- Programs in Genetics, Tufts University School of Medicine, Boston, Massachusetts 02111
| | | | - Philip W Hinds
- Programs in Genetics, Tufts University School of Medicine, Boston, Massachusetts 02111; Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111.
| | - Ananda L Roy
- Programs in Genetics, Tufts University School of Medicine, Boston, Massachusetts 02111; Department of Pathology, Tufts University School of Medicine, Boston, Massachusetts 02111; Programs in Immunology, Tufts University School of Medicine, Boston, Massachusetts 02111.
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Misra U, Wang F, Pizzo S. Transcription factor TFII-I causes transcriptional upregulation of GRP78 synthesis in prostate cancer cells. J Cell Biochem 2009; 106:381-9. [DOI: 10.1002/jcb.22016] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Jergil M, Kultima K, Gustafson AL, Dencker L, Stigson M. Valproic acid-induced deregulation in vitro of genes associated in vivo with neural tube defects. Toxicol Sci 2009; 108:132-48. [PMID: 19136453 DOI: 10.1093/toxsci/kfp002] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The utility of an in vitro system to search for molecular targets and markers of developmental toxicity was explored, using microarrays to detect genes susceptible to deregulation by the teratogen valproic acid (VPA) in the pluripotent mouse embryonal carcinoma cell line P19. Total RNA extracted from P19 cells cultured in the absence or presence of 1, 2.5, or 10mM VPA for 1.5, 6, or 24 h was subjected to replicated microarray analysis, using CodeLink UniSet I Mouse 20K Expression Bioarrays. A moderated F-test revealed a significant VPA response for 2972 (p < 10(-3)) array probes (19.4% of the filtered gene list), 421 of which were significant across all time points. In a core subset of VPA target genes whose expression was downregulated (68 genes) or upregulated (125 genes) with high probability (p < 10(-7)) after both 1.5 and 6 h of VPA exposure, there was a significant enrichment of the biological process Gene Ontology term transcriptional regulation among downregulated genes, and apoptosis among upregulated, and two of the downregulated genes (Folr1 and Gtf2i) have a knockout phenotype comprising exencephaly, the major malformation induced by VPA in mice. The VPA-induced gene expression response in P19 cells indicated that approximately 30% of the approximately 200 genes known from genetic mouse models to be associated with neural tube defects may be potential VPA targets, suggestive of a combined deregulation of multiple genes as a possible mechanism of VPA teratogenicity. Gene expression responses related to other known effects of VPA (histone deacetylase inhibition, G(1)-phase cell cycle arrest, induction of apoptosis) were also identified. This study indicates that toxicogenomic responses to a teratogenic compound in vitro may correlate with known in vitro and in vivo effects, and that short-time (< or =6 h) exposures in such an in vitro system could provide a useful component in mechanistic studies and screening tests in developmental toxicology.
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Affiliation(s)
- Måns Jergil
- Department of Pharmaceutical Biosciences, Division of Toxicology, Uppsala University, BMC, Box 594, SE-75124 Uppsala, Sweden
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Racek T, Buhlmann S, Rüst F, Knoll S, Alla V, Pützer BM. Transcriptional repression of the prosurvival endoplasmic reticulum chaperone GRP78/BIP by E2F1. J Biol Chem 2008; 283:34305-14. [PMID: 18840615 DOI: 10.1074/jbc.m803925200] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The endoplasmic reticulum chaperone GRP78/BIP plays a central role in the prosurvival machinery, and its enhanced expression has been implicated in drug resistance, carcinogenesis, and metastasis. E2F1, as part of an antitumor safeguard mechanism, promotes apoptosis regardless of functional p53. Using cells that are defective in p53, we show that E2F1 represses GRP78/BIP at the transcriptional level, and this requires its DNA binding domain. Analysis of human GRP78/BIP promoter reporter constructs revealed that the region between -371 and -109 of the proximal promoter contains major E2F1-responsive elements. Toward understanding the underlying mechanism of this regulation, we performed chromatin immunoprecipitation and gel shift assays, demonstrating that E2F1 directly binds to GC-rich regions in the distal GC-box and endoplasmic reticulum stress response element -126 by interfering with the binding of positive regulatory proteins Sp1 and TFII-I of the ER stress response element-binding factor complex. We further show that TFII-I, which is required for optimal stress induction of GRP78/BIP, is suppressed by E2F1 on the protein level. Finally, our studies suggest a molecular link between the inhibition of GRP78/BIP and E2F1-mediated chemosensitization of tumor cells, underscoring its relevance for cancer treatment. Together, the data provide a new mechanism for the incompletely understood tumor suppressor function of E2F1.
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Affiliation(s)
- Tomás Racek
- Department of Vectorology and Experimental Gene Therapy, Biomedical Research Center, University of Rostock, 18055 Rostock, Germany
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25
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Lazebnik MB, Tussie-Luna MI, Roy AL. Determination and functional analysis of the consensus binding site for TFII-I family member BEN, implicated in Williams-Beuren syndrome. J Biol Chem 2008; 283:11078-82. [PMID: 18326499 PMCID: PMC2431064 DOI: 10.1074/jbc.c800049200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 03/06/2008] [Indexed: 12/23/2022] Open
Abstract
The ubiquitously expressed TFII-I family of multifunctional transcription factors is involved in gene regulation as well as signaling. Despite the fact that they share significant sequence homology, these factors exhibit varied and distinct functions. The lack of knowledge about its binding sites and physiological target genes makes it more difficult to assign a definitive function for the TFII-I-related protein, BEN. We set out to determine its optimal binding site with the notion of predicting its physiological target genes. Here we report the identification of an optimal binding sequence for BEN by SELEX (systematic evolution of ligands by exponential enrichment) and confirm the relevance of this sequence by functional assays. We further performed a data base search to assign genes that have this consensus site(s) and validate several candidate genes by quantitative PCR upon stable silencing of BEN and by chromatin immunoprecipitation assay upon stable expression of BEN. Given that haploinsufficiency in BEN is causative to Williams-Beuren syndrome, these results may further lead to the identification of a set of physiologically relevant target genes for BEN and may help identify molecular determinants of Williams-Beuren syndrome.
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Affiliation(s)
- Maria B Lazebnik
- Programs in Genetics, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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26
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Ostrakhovitch EA, Olsson PE, von Hofsten J, Cherian MG. P53 mediated regulation of metallothionein transcription in breast cancer cells. J Cell Biochem 2007; 102:1571-83. [PMID: 17477370 DOI: 10.1002/jcb.21381] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Recent studies have shown that only breast cancer epithelial cells with intact p53 can induce metallothionein (MT) synthesis after exposure to metals. In this study, the potential role of p53 on regulation of MT was investigated. Results demonstrate that zinc and copper increased metal response elements (MREs) activity and MTF-1 expression in p53 positive MN1 and parental MCF7 cells. However, inactivation of p53 by treatment with pifithrin-alpha or the presence of inactive p53 inhibited MRE-dependent reporter gene expression in response to metals. MTF-1 levels remained unchanged after treatment with zinc in cells with nonfunctional p53. The introduction of wild-type p53 in MDD2 cells, containing nonfunctional p53, enhanced the ability of zinc to increase MRE-dependent reporter gene expression. The cellular level of p21Cip1/WAF1 was increased in MDD2 cells after p53 transfection, confirming the presence of active p53. The treatment of MN1 and parental MCF7 with trichostatin A led to a sixfold increase in the MRE activity in response to zinc. On the contrary, MRE activity remained unaltered in MDD2 cells with inactive p53. The above results demonstrate that activation of p53 is an important factor in metal regulation of MT.
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Affiliation(s)
- Elena A Ostrakhovitch
- Department of Pathology, University of Western Ontario, London, Ontario N6A 5C1, Canada.
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27
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Roy AL. Signal-induced functions of the transcription factor TFII-I. BIOCHIMICA ET BIOPHYSICA ACTA 2007; 1769:613-21. [PMID: 17976384 PMCID: PMC2140948 DOI: 10.1016/j.bbaexp.2007.10.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Revised: 09/27/2007] [Accepted: 10/01/2007] [Indexed: 12/21/2022]
Abstract
We have learned a great deal over the last several years about the molecular mechanisms that govern cell growth, cell division and cell death. Normal cells pass through cell cycle (growth) and divide in response to mitogenic signals that are transduced through their cognate cell surface receptors to the nucleus. Despite the fact that cellular growth and division are mechanistically distinct steps, they are usually coordinately regulated, which is critical for normal cellular proliferation. The precise mechanistic basis for this coordinated regulation is unclear. TFII-I is a unique, signal-induced multifunctional transcription factor that is activated upon a variety of signaling pathways and appears to participate in distinct phases of cell growth. For instance, TFII-I is required for growth factor-induced transcriptional activation of the c-fos gene, which is essential for cell cycle entry. Two alternatively spliced isoforms of TFII-I exhibit opposing but necessary functions for mitogen-induced transcriptional activation of c-fos. Besides transcriptional activation of the c-fos proto-oncogene and eventual entry into cell cycle, TFII-I also appears to have a role in later phases of the cell cycle and cell division. Here we discuss how a multitude of signaling inputs target TFII-I isoforms, which may exert their functions in distinct phases of the cell cycle and play a key role in the coordinated regulation of cellular proliferation.
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Affiliation(s)
- Ananda L Roy
- Department of Pathology, Tufts University School of Medicine, 150 Harrison Avenue, Boston, MA 02111, USA.
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28
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Ashworth T, Roy AL. Cutting Edge: TFII-I controls B cell proliferation via regulating NF-kappaB. THE JOURNAL OF IMMUNOLOGY 2007; 178:2631-5. [PMID: 17312101 DOI: 10.4049/jimmunol.178.5.2631] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The multifunctional transcription factor TFII-I physically and functionally interacts with Bruton's tyrosine kinase in murine B cells. However, the downstream functions of TFII-I in B cells are unknown. Toward achieving this goal, we established stable posttranscriptional silencing of TFII-I in WEHI-231 immature murine B cells, which undergoes growth arrest and apoptosis either upon anti-IgM or TGF-beta signaling. In this study, we show that TFII-I promotes growth arrest of cells in a signal-dependent manner. Unlike control cells, B cells exhibiting loss of TFII-I function fail to undergo arrest upon signaling due to up-regulation of c-Myc expression and concomitant down-regulation of both p21 and p27. Loss of TFII-I is also associated with simultaneous increase in nuclear c-rel and decrease in p50 homodimer binding. Thus, besides controlling c-myc transcription, TFII-I controls B cell proliferation by regulating both nuclear translocation of c-rel and DNA-binding activity of p50 NF-kappaB.
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Affiliation(s)
- Todd Ashworth
- Program in Immmunology, Department of Pathology, Tufts University School of Medicine, 150 Harrison Avenue, Boston, MA 02111, USA
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29
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Chimge NO, Mungunsukh O, Ruddle F, Bayarsaihan D. Expression profiling of BEN regulated genes in mouse embryonic fibroblasts. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2007; 308:209-24. [PMID: 17041962 DOI: 10.1002/jez.b.21129] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BEN is a member of the TFII-I family of helix-loop-helix transcription factors. Both TFII-I and BEN are involved in gene regulation through interactions with tissue-specific transcription factors and chromatin remodeling complexes. Identification of the downstream target genes of TFII-I proteins is critical in delineating the regulatory effects of these proteins. In this study, we conducted a microarray analysis to determine gene expression alterations following the overexpression of BEN in primary mouse embryonic fibroblasts (MEFs). We found the BEN-dependent modulation in the expression of large groups of genes representing a wide variety of functional categories including genes important in the immune response, cell cycle, transcriptional regulation and cell signaling. A set of genes identified by the microarray analysis was validated by independent real-time PCR analysis. Among upregulated genes were Shrm, Tgfb2, Ube2l6, G1p2, Ccl7 while downregulated genes were Folr1, Tgfbr2, Csrp2, and Dlk1. These results support a versatile function of TFII-I proteins in vertebrate physiology and lead to an increased understanding of the BEN-dependent molecular events.
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Affiliation(s)
- Nyam-Osor Chimge
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520, USA
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30
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Chimge NO, Mungunsukh O, Ruddle F, Bayarsaihan D. Gene expression analysis of TFII-I modulated genes in mouse embryonic fibroblasts. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2007; 308:225-35. [PMID: 17094079 DOI: 10.1002/jez.b.21134] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
TFII-I is a founding member of a family of helix-loop-helix transcription factors involved in modulation of genes through interaction with various nuclear factors and chromatin remodeling complexes. Recent studies indicate that TFII-I performs important function in cell physiology and mouse embryogenesis. In order to understand its molecular role, TFII-I was overexpressed in primary mouse embryonic fibroblasts (MEFs) and alterations in gene expression were monitored with a mouse 16 K oligonucleotide microarray. These studies allowed us to identify genes that lie downstream of TFII-I-dependent pathways. Among the modulated candidates were genes involved in the immunity response, catalytic activity, signaling pathways and transcriptional regulation. Expression of several candidates including those for the interferon-stimulated protein (G1p2), small inducible cytokine A7 (Ccl7), ubiquitin-conjugating enzyme 8 (Ube2l6), cysteine-rich protein (Csrp2) and Drosophila delta-like 1 homolog (Dlk1) were confirmed by real-time PCR. The obtained results suggest that TFII-I participates in multiple signaling and regulatory pathways in MEFs.
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Affiliation(s)
- Nyam-Osor Chimge
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520, USA
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31
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Hakre S, Tussie-Luna MI, Ashworth T, Novina CD, Settleman J, Sharp PA, Roy AL. Opposing functions of TFII-I spliced isoforms in growth factor-induced gene expression. Mol Cell 2006; 24:301-8. [PMID: 17052463 DOI: 10.1016/j.molcel.2006.09.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2006] [Revised: 07/18/2006] [Accepted: 09/11/2006] [Indexed: 11/12/2022]
Abstract
Multifunctional transcription factor TFII-I has two spliced isoforms (Delta and beta) in murine fibroblasts. Here we show that these isoforms have distinct subcellular localization and mutually exclusive transcription functions in the context of growth factor signaling. In the absence of signaling, TFII-Ibeta is nuclear and recruited to the c-fos promoter in vivo. But upon growth factor stimulation, the promoter recruitment is abolished and it is exported out of the nucleus. Moreover, isoform-specific silencing of TFII-Ibeta results in transcriptional activation of the c-fos gene. In contrast, TFII-IDelta is largely cytoplasmic in the resting state but translocates to the nucleus upon growth factor signaling, undergoes signal-induced recruitment to the same site on the c-fos promoter, and activates the gene. Importantly, activated TFII-IDelta interacts with Erk1/2 (MAPK) kinase in the cell cytoplasm and imports the Erk1/2 to the nucleus, thereby transducing growth factor signaling. Our results identify a unique growth factor signaling pathway controlled by opposing activities of two TFII-I spliced isoforms.
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Affiliation(s)
- Shweta Hakre
- Program in Immunology, Tufts University School of Medicine, 150 Harrison Avenue, Boston, Massachusetts 02111, USA
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