1
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Sriram S, Kim KW, Ljunggren-Rose Å. Targeted DeSUMOylation as a therapeutic strategy for multiple sclerosis. J Neuroimmunol 2024; 392:578371. [PMID: 38788318 DOI: 10.1016/j.jneuroim.2024.578371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/07/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024]
Abstract
SUMO (small ubiquitin like modifier) conjugated proteins have emerged as an important post translational modifier of cellular function. SUMOylation modulates several cellular processes involved in transcriptional regulation of genes, protein-protein interactions and DNA damage and repair. Since abnormalities in SUMOylation has been observed in neoplastic and neurodegenerative disorders, the SUMO pathway has become an attractive site for targeting of new therapies to regulate SUMOylation and reduce disease burden. Conjugation of SUMO to their respective substrates is orchestrated by an enzymatic cascade involving three main enzymes, E1, activation enzyme, E2, conjugating enzyme and E3, a protein ligase. Each of these enzymes are therefore potential "druggable" sites for future therapeutics. SUMOylation is a well-known mechanism by which the innate immune response is regulated in response to viral infections and in the adaptive immune response to tumor immunity. We have shown that small molecules which inhibit the SUMO activation pathway are also capable of inhibiting autoimmune response. TAK981 which forms adducts with SUMO and anacardic acid which inhibits the E1 enzyme of the SUMO pathway were effective in preventing the development of experimental allergic encephalitis (EAE), a mouse model of multiple sclerosis. Anacardic acid and TAK981 inhibited activation of TH17 cells and reduced clinical and pathological injury in IL-17 mediated myelin oligodendrocyte glycoprotein (MOG) induced EAE. Ginkgolic acid, another known inhibitor of SUMO pathway, was also shown to be effective in reducing the severity of inflammatory arthropathies which is also IL-17 mediated. In addition, the increase in the transcription of myelin genes with TAK981 and anacardic acid improved remyelination in experimental models of demyelination. In the present review paper, we examine the mechanism of action of inhibitors of the SUMO pathway on regulating the immune response and the possibility of the use of these agents as therapeutics for MS.
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Affiliation(s)
- S Sriram
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, USA.
| | - Kwang Woon Kim
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, USA
| | - Åsa Ljunggren-Rose
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, USA
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2
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Kuehn HS, Sakovich IS, Niemela JE, Gil Silva AA, Stoddard JL, Polyakova EA, Esteve Sole A, Aleshkevich SN, Uglova TA, Belevtsev MV, Vertelko VR, Shman TV, Kupchinskaya AN, Walter JE, Fleisher TA, Notarangelo LD, Peng XP, Delmonte OM, Sharapova SO, Rosenzweig SD. Disease-associated AIOLOS variants lead to immune deficiency/dysregulation by haploinsufficiency and redefine AIOLOS functional domains. J Clin Invest 2024; 134:e172573. [PMID: 38015619 PMCID: PMC10836806 DOI: 10.1172/jci172573] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 11/21/2023] [Indexed: 11/30/2023] Open
Abstract
AIOLOS, also known as IKZF3, is a transcription factor that is highly expressed in the lymphoid lineage and is critical for lymphocyte differentiation and development. Here, we report on 9 individuals from 3 unrelated families carrying AIOLOS variants Q402* or E82K, which led to AIOLOS haploinsufficiency through different mechanisms of action. Nonsense mutant Q402* displayed abnormal DNA binding, pericentromeric targeting, posttranscriptional modification, and transcriptome regulation. Structurally, the mutant lacked the AIOLOS zinc finger (ZF) 5-6 dimerization domain, but was still able to homodimerize with WT AIOLOS and negatively regulate DNA binding through ZF1, a previously unrecognized function for this domain. Missense mutant E82K showed overall normal AIOLOS functions; however, by affecting a redefined AIOLOS protein stability domain, it also led to haploinsufficiency. Patients with AIOLOS haploinsufficiency showed hypogammaglobulinemia, recurrent infections, autoimmunity, and allergy, but with incomplete clinical penetrance. Altogether, these data redefine the AIOLOS structure-function relationship and expand the spectrum of AIOLOS-associated diseases.
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Affiliation(s)
- Hye Sun Kuehn
- Immunology Service, Department of Laboratory Medicine, Clinical Center, NIH, Bethesda, Maryland, USA
| | - Inga S. Sakovich
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Julie E. Niemela
- Immunology Service, Department of Laboratory Medicine, Clinical Center, NIH, Bethesda, Maryland, USA
| | - Agustin A. Gil Silva
- Immunology Service, Department of Laboratory Medicine, Clinical Center, NIH, Bethesda, Maryland, USA
| | - Jennifer L. Stoddard
- Immunology Service, Department of Laboratory Medicine, Clinical Center, NIH, Bethesda, Maryland, USA
| | - Ekaterina A. Polyakova
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Ana Esteve Sole
- Immunology Service, Department of Laboratory Medicine, Clinical Center, NIH, Bethesda, Maryland, USA
| | - Svetlana N. Aleshkevich
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Tatjana A. Uglova
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Mikhail V. Belevtsev
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Vladislav R. Vertelko
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Tatsiana V. Shman
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Aleksandra N. Kupchinskaya
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Jolan E. Walter
- Division of Allergy and Immunology, Department of Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
- Division of Allergy and Immunology, Department of Medicine, Johns Hopkins All Children’s Hospital, St. Petersburg, Florida, USA
- Division of Pediatric Allergy and Immunology, Massachusetts General Hospital for Children, Boston, Massachusetts, USA
| | - Thomas A. Fleisher
- Immunology Service, Department of Laboratory Medicine, Clinical Center, NIH, Bethesda, Maryland, USA
| | - Luigi D. Notarangelo
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy of Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Xiao P. Peng
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ottavia M. Delmonte
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy of Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Svetlana O. Sharapova
- Research Department, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus
| | - Sergio D. Rosenzweig
- Immunology Service, Department of Laboratory Medicine, Clinical Center, NIH, Bethesda, Maryland, USA
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3
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Kim KW, Ljunggren-Rose Å, Matta P, Toki S, Sriram S. Inhibition of SUMOylation promotes remyelination and reduces IL-17 mediated autoimmune inflammation: Novel approach toward treatment of inflammatory CNS demyelinating disease. J Neuroimmunol 2023; 384:578219. [PMID: 37813042 DOI: 10.1016/j.jneuroim.2023.578219] [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: 07/14/2023] [Revised: 09/11/2023] [Accepted: 10/01/2023] [Indexed: 10/11/2023]
Abstract
Small ubiquitin like modifiers (SUMO) are reversible posttranslational modifiers of intracellular proteins. In the CNS, expression of myelin genes is regulated by state of SUMOylation of their respective transcription factors. In the immune system, deSUMOylation activates innate immune responses and promotes anti-viral immunity. However, the role played by SUMO in an adaptive immune response and in the development of T cell mediated autoimmune disease has not been previously described. TAK981 is a synthetic small molecule which by forming adducts with SUMO proteins prevents SUMOylation. We examined the expression of myelin genes and their transcription factors following culture with TAK981 in Oligodendrocyte Precursor Cells (OPC). We found that myelin basic protein (MBP), a key myelin protein, is upregulated in OPC in the presence of TAK981. We also found increased expression of transcription factors Sox10 and Myrf, which engage in the expression of MBP. In the Cuprizone model of demyelination/remyelination, animals which were treated with TAK981 showed increased remyelination in areas of demyelination and an increase in the number of maturing oligodendrocytes compared to vehicle treated controls. In in vitro cultures of lymphocytes, TAK981 reduced the expression of TH17 in T cells in mice immunized with MOGp35-55. Following in vivo treatment with TAK981, there was a significant reduction in the clinical and pathological severity in mice immunized to develop experimental allergic encephalitis (EAE). The dual effects of deSUMOylation on remyelination and in regulating an autoimmune adaptive response offers a novel approach to the management of human inflammatory demyelinating diseases such as multiple sclerosis.
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Affiliation(s)
- Kwang Woon Kim
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, United States of America
| | - Åsa Ljunggren-Rose
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, United States of America
| | - Pranathi Matta
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, United States of America
| | - Shinji Toki
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37212, United States of America
| | - Subramaniam Sriram
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, United States of America.
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4
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Affar M, Bottardi S, Quansah N, Lemarié M, Ramón AC, Affar EB, Milot E. IKAROS: from chromatin organization to transcriptional elongation control. Cell Death Differ 2023:10.1038/s41418-023-01212-2. [PMID: 37620540 DOI: 10.1038/s41418-023-01212-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 07/26/2023] [Accepted: 08/14/2023] [Indexed: 08/26/2023] Open
Abstract
IKAROS is a master regulator of cell fate determination in lymphoid and other hematopoietic cells. This transcription factor orchestrates the association of epigenetic regulators with chromatin, ensuring the expression pattern of target genes in a developmental and lineage-specific manner. Disruption of IKAROS function has been associated with the development of acute lymphocytic leukemia, lymphoma, chronic myeloid leukemia and immune disorders. Paradoxically, while IKAROS has been shown to be a tumor suppressor, it has also been identified as a key therapeutic target in the treatment of various forms of hematological malignancies, including multiple myeloma. Indeed, targeted proteolysis of IKAROS is associated with decreased proliferation and increased death of malignant cells. Although the molecular mechanisms have not been elucidated, the expression levels of IKAROS are variable during hematopoiesis and could therefore be a key determinant in explaining how its absence can have seemingly opposite effects. Mechanistically, IKAROS collaborates with a variety of proteins and complexes controlling chromatin organization at gene regulatory regions, including the Nucleosome Remodeling and Deacetylase complex, and may facilitate transcriptional repression or activation of specific genes. Several transcriptional regulatory functions of IKAROS have been proposed. An emerging mechanism of action involves the ability of IKAROS to promote gene repression or activation through its interaction with the RNA polymerase II machinery, which influences pausing and productive transcription at specific genes. This control appears to be influenced by IKAROS expression levels and isoform production. In here, we summarize the current state of knowledge about the biological roles and mechanisms by which IKAROS regulates gene expression. We highlight the dynamic regulation of this factor by post-translational modifications. Finally, potential avenues to explain how IKAROS destruction may be favorable in the treatment of certain hematological malignancies are also explored.
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Affiliation(s)
- Malik Affar
- Faculty of Medicine, University of Montreal, Montréal, QC, Canada
- Maisonneuve-Rosemont Hospital Research Center, CIUSSS de l'Est-de-l'Île de Montréal, 5415 boulevard de l'Assomption, Montréal, QC, H1T 2M4, Canada
| | - Stefania Bottardi
- Maisonneuve-Rosemont Hospital Research Center, CIUSSS de l'Est-de-l'Île de Montréal, 5415 boulevard de l'Assomption, Montréal, QC, H1T 2M4, Canada
| | - Norreen Quansah
- Maisonneuve-Rosemont Hospital Research Center, CIUSSS de l'Est-de-l'Île de Montréal, 5415 boulevard de l'Assomption, Montréal, QC, H1T 2M4, Canada
| | - Maud Lemarié
- Faculty of Medicine, University of Montreal, Montréal, QC, Canada
- Maisonneuve-Rosemont Hospital Research Center, CIUSSS de l'Est-de-l'Île de Montréal, 5415 boulevard de l'Assomption, Montréal, QC, H1T 2M4, Canada
| | - Ailyn C Ramón
- Faculty of Medicine, University of Montreal, Montréal, QC, Canada
- Maisonneuve-Rosemont Hospital Research Center, CIUSSS de l'Est-de-l'Île de Montréal, 5415 boulevard de l'Assomption, Montréal, QC, H1T 2M4, Canada
| | - El Bachir Affar
- Faculty of Medicine, University of Montreal, Montréal, QC, Canada.
- Maisonneuve-Rosemont Hospital Research Center, CIUSSS de l'Est-de-l'Île de Montréal, 5415 boulevard de l'Assomption, Montréal, QC, H1T 2M4, Canada.
| | - Eric Milot
- Faculty of Medicine, University of Montreal, Montréal, QC, Canada.
- Maisonneuve-Rosemont Hospital Research Center, CIUSSS de l'Est-de-l'Île de Montréal, 5415 boulevard de l'Assomption, Montréal, QC, H1T 2M4, Canada.
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5
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Protein Kinase CK2 and Epstein-Barr Virus. Biomedicines 2023; 11:biomedicines11020358. [PMID: 36830895 PMCID: PMC9953236 DOI: 10.3390/biomedicines11020358] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 01/28/2023] Open
Abstract
Protein kinase CK2 is a pleiotropic protein kinase, which phosphorylates a number of cellular and viral proteins. Thereby, this kinase is implicated in the regulation of cellular signaling, controlling of cell proliferation, apoptosis, angiogenesis, immune response, migration and invasion. In general, viruses use host signaling mechanisms for the replication of their genome as well as for cell transformation leading to cancer. Therefore, it is not surprising that CK2 also plays a role in controlling viral infection and the generation of cancer cells. Epstein-Barr virus (EBV) lytically infects epithelial cells of the oropharynx and B cells. These latently infected B cells subsequently become resting memory B cells when passing the germinal center. Importantly, EBV is responsible for the generation of tumors such as Burkitt's lymphoma. EBV was one of the first human viruses, which was connected to CK2 in the early nineties of the last century. The present review shows that protein kinase CK2 phosphorylates EBV encoded proteins as well as cellular proteins, which are implicated in the lytic and persistent infection and in EBV-induced neoplastic transformation. EBV-encoded and CK2-phosphorylated proteins together with CK2-phosphorylated cellular signaling proteins have the potential to provide efficient virus replication and cell transformation. Since there are powerful inhibitors known for CK2 kinase activity, CK2 might become an attractive target for the inhibition of EBV replication and cell transformation.
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6
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Xia R, Cheng Y, Han X, Wei Y, Wei X. Ikaros Proteins in Tumor: Current Perspectives and New Developments. Front Mol Biosci 2021; 8:788440. [PMID: 34950704 PMCID: PMC8689071 DOI: 10.3389/fmolb.2021.788440] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 11/09/2021] [Indexed: 02/05/2023] Open
Abstract
Ikaros is a zinc finger transcription factor (TF) of the Krüppel family member, which significantly regulates normal lymphopoiesis and tumorigenesis. Ikaros can directly initiate or suppress tumor suppressors or oncogenes, consequently regulating the survival and proliferation of cancer cells. Over recent decades, a series of studies have been devoted to exploring and clarifying the relationship between Ikaros and associated tumors. Therapeutic strategies targeting Ikaros have shown promising therapeutic effects in both pre-clinical and clinical trials. Nevertheless, the increasingly prominent problem of drug resistance targeted to Ikaros and its analog is gradually appearing in our field of vision. This article reviews the role of Ikaros in tumorigenesis, the mechanism of drug resistance, the progress of targeting Ikaros in both pre-clinical and clinical trials, and the potential use of associated therapy in cancer therapy.
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Affiliation(s)
- Ruolan Xia
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Yuan Cheng
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Xuejiao Han
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Yuquan Wei
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Xiawei Wei
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
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7
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Shahin T, Kuehn HS, Shoeb MR, Gawriyski L, Giuliani S, Repiscak P, Hoeger B, Yüce Petronczki Ö, Bal SK, Zoghi S, Dmytrus J, Seruggia D, Castanon I, Rezaei N, Varjosalo M, Halbritter F, Rosenzweig SD, Boztug K. Germline biallelic mutation affecting the transcription factor Helios causes pleiotropic defects of immunity. Sci Immunol 2021; 6:eabe3981. [PMID: 34826259 DOI: 10.1126/sciimmunol.abe3981] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Tala Shahin
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria.,CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Hye Sun Kuehn
- Immunology Service, Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20814, USA
| | - Mohamed R Shoeb
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria
| | - Lisa Gawriyski
- Institute of Biotechnology, Helsinki Institute of Life Science, Proteomics Unit, University of Helsinki, Helsinki, Finland
| | - Sarah Giuliani
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Peter Repiscak
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria
| | - Birgit Hoeger
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Özlem Yüce Petronczki
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Sevgi Köstel Bal
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Samaneh Zoghi
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Jasmin Dmytrus
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Davide Seruggia
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria
| | - Irinka Castanon
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran.,Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Markku Varjosalo
- Institute of Biotechnology, Helsinki Institute of Life Science, Proteomics Unit, University of Helsinki, Helsinki, Finland
| | | | - Sergio D Rosenzweig
- Immunology Service, Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD 20814, USA
| | - Kaan Boztug
- St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria.,CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,St. Anna Children's Hospital, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
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8
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Ramirez NJ, Posadas-Cantera S, Caballero-Oteyza A, Camacho-Ordonez N, Grimbacher B. There is no gene for CVID - novel monogenetic causes for primary antibody deficiency. Curr Opin Immunol 2021; 72:176-185. [PMID: 34153571 DOI: 10.1016/j.coi.2021.05.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 12/25/2022]
Abstract
'There is no gene for fate' (citation from the movie 'GATTACA') - and there is no gene for CVID. Common Variable ImmunoDeficiency (CVID) is the most prevalent primary immunodeficiency in humans. CVID is characterized by an increased susceptibility to infections, hypogammaglobulinemia, reduced switched memory B cell numbers in peripheral blood and a defective response to vaccination, often complicated by autoimmune and autoinflammatory conditions. However, as soon as a genetic diagnosis has been made in a patient with CVID, the diagnosis must be changed to the respective genetic cause (www.esid.org). Therefore, there are genetic causes for primary antibody deficiencies, but not for CVID. Primary antibody deficiencies (PADs) are a heterogeneous group of disorders. Several attempts have been made to gain further insights into the pathogenesis of PAD, using unbiased approaches such as whole exome or genome sequencing. Today, in just about 35% of cases with PAD, monogenic mutations (including those in the gene TNFRSF13B) can be identified in a set of 68 genes [1•]. These mutations occur either sporadically or are inherited and do explain an often complex phenotype. In our review, we not only discuss gene defects identified in PAD patients previously diagnosed with CVID and/or CVID-like disorders such as IKZF1, CTNNBL1, TNFSF13 and BACH2, but also genetic defects which were initially described in non-CVID patients but have later also been observed in patients with PAD such as PLCG2, PIK3CG, PMS2, RNF31, KMT2D, STAT3. We also included interesting genetic defects in which the pathophysiology suggests a close relation to other known defects of the adaptive immune response, such as DEF6, SAMD9 and SAMD9L, and hence a CVID-like phenotype may be observed in the future. However, alternative mechanisms most likely add to the development of an antibody-deficient phenotype, such as polygenic origins, epigenetic changes, and/or environmental factors.
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Affiliation(s)
- Neftali J Ramirez
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany; Integrated Research Training Group (IRTG) Medical Epigenetics, Collaborative Research Centre 992, Freiburg, Germany; Faculty of Biology, Albert-Ludwigs-University of Freiburg, Germany
| | - Sara Posadas-Cantera
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Andrés Caballero-Oteyza
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany; RESIST - Cluster of Excellence 2155 to Hanover Medical School, Satellite Center Freiburg, Freiburg, Germany
| | - Nadezhda Camacho-Ordonez
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany; Faculty of Biology, Albert-Ludwigs-University of Freiburg, Germany
| | - Bodo Grimbacher
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany; DZIF - German Center for Infection Research, Satellite Center Freiburg, Freiburg, Germany; CIBSS - Centre for Integrative Biological Signalling Studies, Albert-Ludwigs University, Freiburg, Germany; RESIST - Cluster of Excellence 2155 to Hanover Medical School, Satellite Center Freiburg, Freiburg, Germany.
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9
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Germline IKAROS dimerization haploinsufficiency causes hematologic cytopenias and malignancies. Blood 2021; 137:349-363. [PMID: 32845957 DOI: 10.1182/blood.2020007292] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/11/2020] [Indexed: 02/07/2023] Open
Abstract
IKAROS is a transcription factor forming homo- and heterodimers and regulating lymphocyte development and function. Germline mutations affecting the IKAROS N-terminal DNA binding domain, acting in a haploinsufficient or dominant-negative manner, cause immunodeficiency. Herein, we describe 4 germline heterozygous IKAROS variants affecting its C-terminal dimerization domain, via haploinsufficiency, in 4 unrelated families. Index patients presented with hematologic disease consisting of cytopenias (thrombocytopenia, anemia, neutropenia)/Evans syndrome and malignancies (T-cell acute lymphoblastic leukemia, Burkitt lymphoma). These dimerization defective mutants disrupt homo- and heterodimerization in a complete or partial manner, but they do not affect the wild-type allele function. Moreover, they alter key mechanisms of IKAROS gene regulation, including sumoylation, protein stability, and the recruitment of the nucleosome remodeling and deacetylase complex; none affected in N-terminal DNA binding defects. These C-terminal dimerization mutations are largely associated with hematologic disorders, display dimerization haploinsufficiency and incomplete clinical penetrance, and differ from previously reported allelic variants in their mechanism of action. Dimerization mutants contribute to the growing spectrum of IKAROS-associated diseases displaying a genotype-phenotype correlation.
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10
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Boulanger M, Chakraborty M, Tempé D, Piechaczyk M, Bossis G. SUMO and Transcriptional Regulation: The Lessons of Large-Scale Proteomic, Modifomic and Genomic Studies. Molecules 2021; 26:molecules26040828. [PMID: 33562565 PMCID: PMC7915335 DOI: 10.3390/molecules26040828] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
One major role of the eukaryotic peptidic post-translational modifier SUMO in the cell is transcriptional control. This occurs via modification of virtually all classes of transcriptional actors, which include transcription factors, transcriptional coregulators, diverse chromatin components, as well as Pol I-, Pol II- and Pol III transcriptional machineries and their regulators. For many years, the role of SUMOylation has essentially been studied on individual proteins, or small groups of proteins, principally dealing with Pol II-mediated transcription. This provided only a fragmentary view of how SUMOylation controls transcription. The recent advent of large-scale proteomic, modifomic and genomic studies has however considerably refined our perception of the part played by SUMO in gene expression control. We review here these developments and the new concepts they are at the origin of, together with the limitations of our knowledge. How they illuminate the SUMO-dependent transcriptional mechanisms that have been characterized thus far and how they impact our view of SUMO-dependent chromatin organization are also considered.
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Affiliation(s)
- Mathias Boulanger
- Institut de Génétique Moléculaire de Montpellier (IGMM), University of Montpellier, CNRS, Montpellier, France; (M.B.); (M.C.); (D.T.)
- Equipe Labellisée Ligue Contre le Cancer, Paris, France
| | - Mehuli Chakraborty
- Institut de Génétique Moléculaire de Montpellier (IGMM), University of Montpellier, CNRS, Montpellier, France; (M.B.); (M.C.); (D.T.)
- Equipe Labellisée Ligue Contre le Cancer, Paris, France
| | - Denis Tempé
- Institut de Génétique Moléculaire de Montpellier (IGMM), University of Montpellier, CNRS, Montpellier, France; (M.B.); (M.C.); (D.T.)
- Equipe Labellisée Ligue Contre le Cancer, Paris, France
| | - Marc Piechaczyk
- Institut de Génétique Moléculaire de Montpellier (IGMM), University of Montpellier, CNRS, Montpellier, France; (M.B.); (M.C.); (D.T.)
- Equipe Labellisée Ligue Contre le Cancer, Paris, France
- Correspondence: (M.P.); (G.B.)
| | - Guillaume Bossis
- Institut de Génétique Moléculaire de Montpellier (IGMM), University of Montpellier, CNRS, Montpellier, France; (M.B.); (M.C.); (D.T.)
- Equipe Labellisée Ligue Contre le Cancer, Paris, France
- Correspondence: (M.P.); (G.B.)
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11
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Read KA, Jones DM, Freud AG, Oestreich KJ. Established and emergent roles for Ikaros transcription factors in lymphoid cell development and function. Immunol Rev 2020; 300:82-99. [PMID: 33331000 DOI: 10.1111/imr.12936] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/12/2020] [Accepted: 11/20/2020] [Indexed: 02/06/2023]
Abstract
Ikaros zinc finger transcription factors are important regulators of the gene programs underlying the development of hematopoietic cell lineages. The family consists of five members: Ikaros, Helios, Aiolos, Eos, and Pegasus, which engage in both homo- and heterotypic intrafamilial interactions to exert diverse functional effects. Pioneering studies focused on the role of these factors in early lymphoid development, as their absence resulted in severe defects in lymphocyte populations. More recent work has now begun to define nuanced, stage-specific roles for Ikaros family members in the differentiation and function of mature T, B, and innate lymphoid cell populations including natural killer (NK) cells. The precise transcriptional mechanisms by which these factors function, both independently and collaboratively, is an area of active investigation. However, several key themes appear to be emerging regarding the pathways influenced by Ikaros family members, including the end-to-end regulation of cytokine signaling. Here, we review roles for Ikaros factors in lymphoid cell development, differentiation, and function, including a discussion of the current understanding of the transcriptional mechanisms they employ and considerations for the future study of this important transcription factor family.
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Affiliation(s)
- Kaitlin A Read
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH, USA.,Biomedical Sciences Graduate Program, Columbus, OH, USA
| | - Devin M Jones
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH, USA.,Biomedical Sciences Graduate Program, Columbus, OH, USA
| | - Aharon G Freud
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH, USA.,Department of Pathology, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH, USA
| | - Kenneth J Oestreich
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH, USA
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12
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Regulation of Small GTPase Rab20 by Ikaros in B-Cell Acute Lymphoblastic Leukemia. Int J Mol Sci 2020; 21:ijms21051718. [PMID: 32138279 PMCID: PMC7084408 DOI: 10.3390/ijms21051718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Revised: 02/20/2020] [Accepted: 02/29/2020] [Indexed: 12/18/2022] Open
Abstract
Ikaros is a DNA-binding protein that regulates gene expression and functions as a tumor suppressor in B-cell acute lymphoblastic leukemia (B-ALL). The full cohort of Ikaros target genes have yet to be identified. Here, we demonstrate that Ikaros directly regulates expression of the small GTPase, Rab20. Using ChIP-seq and qChIP we assessed Ikaros binding and the epigenetic signature at the RAB20 promoter. Expression of Ikaros, CK2, and RAB20 was determined by qRT-PCR. Overexpression of Ikaros was achieved by retroviral transduction, whereas shRNA was used to knockdown Ikaros and CK2. Regulation of transcription from the RAB20 promoter was analyzed by luciferase reporter assay. The results showed that Ikaros binds the RAB20 promoter in B-ALL. Gain-of-function and loss-of-function experiments demonstrated that Ikaros represses RAB20 transcription via chromatin remodeling. Phosphorylation by CK2 kinase reduces Ikaros’ affinity toward the RAB20 promoter and abolishes its ability to repress RAB20 transcription. Dephosphorylation by PP1 phosphatase enhances both Ikaros’ DNA-binding affinity toward the RAB20 promoter and RAB20 repression. In conclusion, the results demonstrated opposing effects of CK2 and PP1 on expression of Rab20 via control of Ikaros’ activity as a transcriptional regulator. A novel regulatory signaling network in B-cell leukemia that involves CK2, PP1, Ikaros, and Rab20 is identified.
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13
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Zhu B, Cui G, Zhang Q, Cheng X, Tang S. Desumoylation of aggrecan and collagen II facilitates degradation via aggrecanases in IL-1β-mediated osteoarthritis. J Pain Res 2019; 12:2145-2153. [PMID: 31372032 PMCID: PMC6634300 DOI: 10.2147/jpr.s194306] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 04/01/2019] [Indexed: 12/29/2022] Open
Abstract
Background: Aggrecan plays a crucial role in the ability of tissues to withstand compressive loads during the pathological progression of osteoarthritis (OA). Progressive loss of aggrecan from cartilage may result in exposure of the collagen matrix and can lead to its disintegration by metalloproteases. Although aggrecanases are expressed constitutively in human chondrocytes, the degradation of aggrecan is induced by proinflammatory cytokines; however, little is known about the underlying mechanisms. Methods: Human primary chondrocytes from OA patients or healthy donors and human chondrogenic SW1353 cells were cultured and stimulated with IL-1β in vitro, the mRNA expressions and protein levels of MMP-13, ADAMTS-4, ADAMTS-5, SENP1, and SENP2 were determined using real time PCR and Western blot, respectively. The localizations of aggrecan and Col-II, as well as the SUMOylation modification of these proteins were analyzed using immunofluorescence and immunoprecipitation assays, respectively. Results: Our results showed that a proinflammatory cytokine interleukin-1β induced the OA model and desumoylation of aggrecan and collagen type II because the small ubiquitin-like modifier 2/3 (SUMO2/3) was co-localized with aggrecan and collagen type II proteins and interacted physically with them. Mechanistic studies have shown that knockdown of SUMO2/3 expression can significantly enhance the rate of degradation of aggrecan and collagen type II at both the mRNA and protein levels in the OA model. In addition, SUMO-specific protease 2 (SENP2) plays important roles in the desumoylation of aggrecan, while knockdown of SENP2 can protect aggrecan and collagen type II. Clinical assays have shown that OA patients have higher SENP2 levels than healthy controls, and the SENP2 level correlates negatively with both aggrecan and collagen type II levels. Conclusion: SENP2 desumoylates aggrecan and collagen type II proteins in the inflammation induced OA, and SENP2 expression correlates with OA progression.
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Affiliation(s)
- Bing Zhu
- Department of Joint Surgery, The Affiliated Hospital of Weifang Medical University, Weifang, Shandong, People's Republic of China
| | - Guanxing Cui
- Department of Joint Surgery, The Affiliated Hospital of Weifang Medical University, Weifang, Shandong, People's Republic of China
| | - Qifu Zhang
- Department of Cancer Radiotherapy, The Affiliated Hospital of Weifang Medical University, Weifang, Shandong, People's Republic of China
| | - Xiankui Cheng
- Department of Pathology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, People's Republic of China
| | - Shusen Tang
- Department of Joint Surgery, The Affiliated Hospital of Weifang Medical University, Weifang, Shandong, People's Republic of China
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14
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Srinivasan S, Shankar SR, Wang Y, Taneja R. SUMOylation of G9a regulates its function as an activator of myoblast proliferation. Cell Death Dis 2019; 10:250. [PMID: 30867409 PMCID: PMC6416281 DOI: 10.1038/s41419-019-1465-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/13/2019] [Accepted: 02/20/2019] [Indexed: 02/03/2023]
Abstract
The lysine methyltransferase G9a plays a role in many cellular processes. It is a potent repressor of gene expression, a function attributed to its ability to methylate histone and non-histone proteins. Paradoxically, in some instances, G9a can activate gene expression. However, regulators of G9a expression and activity are poorly understood. In this study, we report that endogenous G9a is SUMOylated in proliferating skeletal myoblasts. There are four potential SUMOylation consensus motifs in G9a. Mutation of all four acceptor lysine residues [K79, K152, K256, and K799] inhibits SUMOylation. Interestingly, SUMOylation does not impact G9a-mediated repression of MyoD transcriptional activity or myogenic differentiation. In contrast, SUMO-defective G9a is unable to enhance proliferation of myoblasts. Using complementation experiments, we show that the proliferation defect of primary myoblasts from conditional G9a-deficient mice is rescued by re-expression of wild-type, but not SUMOylation-defective, G9a. Mechanistically, SUMOylation acts as signal for PCAF (P300/CBP-associated factor) recruitment at E2F1-target genes. This results in increased histone H3 lysine 9 acetylation marks at E2F1-target gene promoters that are required for S-phase progression. Our studies provide evidence by which SUMO modification of G9a influences the chromatin environment to impact cell cycle progression.
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Affiliation(s)
- Shruti Srinivasan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117593, Singapore, Singapore
| | - Shilpa Rani Shankar
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117593, Singapore, Singapore
| | - Yaju Wang
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117593, Singapore, Singapore
| | - Reshma Taneja
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117593, Singapore, Singapore.
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15
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Jing X, Wu H, Cheng X, Chen X, Zhang Y, Shi M, Zhang T, Wang X, Zhao R. MLLT10 promotes tumor migration, invasion, and metastasis in human colorectal cancer. Scand J Gastroenterol 2018; 53:964-971. [PMID: 30102091 DOI: 10.1080/00365521.2018.1481521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Colorectal cancer (CRC), one of the most aggressive gastrointestinal malignancies, is a frequently diagnosed life-threatening cancer worldwide. Most CRC patients have poor prognosis mainly because of frequent metastasis and recurrence. Thus, it is crucial to find out some new biomarkers and to show deeper insights into the mechanisms of CRC. MLLT10, Myeloid/lymphoid or mixed-lineage leukemia translocated to 10, also known as AF10, a recurrent MLL partner. In this study, we found that MLLT10 promotes CRC tumor invasion and metastasis both in vitro and in vivo. METHODS Here, the expression of MLLT10 was evaluated by immunohistochemistry. Then, the plasmid and lentivirus particles for MLLT10 overexpression or knockdown were designed and constructed into SW620 and HT29 cells. Finally, cell proliferation assay, cell adhesion assay, transwell migration, and invasion assay were used to detect the migration and invasion ability of MLLT10 in CRC cells. A tail vein injection assay was employed to evaluate the role of MLLT10 in tumor metastases. RESULTS MLLT10 expression was significantly higher in CRC tissues than in noncancerous tissues and was associated with some clinicopathological factors. In vitro, the overexpression of MLLT10 promoted CRC cell migration and invasion, while after MLLT10 was knocked down, the opposite results were observed. Furthermore, we used animal metastasis models to detect the function of MLLT10 in vivo, the results are same with the outcomes in vitro. In lung metastasis sites, the knockdown of MLLT10 in SW620 cells significantly inhibited Vimentin expression, whereas the E-Cadherin was increased. CONCLUSIONS These results indicate that MLLT10 regulates the metastasis of CRC cells via EMT.
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Affiliation(s)
- Xiaoqian Jing
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Haoxuan Wu
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Xi Cheng
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Xianze Chen
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Yaqi Zhang
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Minmin Shi
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Tao Zhang
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Xiongjun Wang
- b Precise Genome Engineering Center, School of Life Sciences , Guangzhou University , Guangzhou , China
| | - Ren Zhao
- a Department of Surgery, Ruijin Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
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16
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Wang L, Liu X, Wang H, Yuan H, Chen S, Chen Z, The H, Zhou J, Zhu J. RNF4 regulates zebrafish granulopoiesis through the DNMT1‐C/EBPα axis. FASEB J 2018; 32:4930-4940. [DOI: 10.1096/fj.201701450rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Luxiang Wang
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Xiaohui Liu
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Haihong Wang
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Hao Yuan
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Saijuan Chen
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Zhu Chen
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Hugues The
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Equipe Labellisée No. 11 Ligue Nationale Contre le CancerHôpital St. LouisUniversité de Paris 7/INSERM/CNRS UMR 944/7212ParisFrance
| | - Jun Zhou
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Jun Zhu
- CNRS-LIA Hematology and CancerSino-French Research Center for Life Sciences and GenomicsState Key Laboratory of Medical GenomicsRui-Jin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Equipe Labellisée No. 11 Ligue Nationale Contre le CancerHôpital St. LouisUniversité de Paris 7/INSERM/CNRS UMR 944/7212ParisFrance
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17
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Abstract
Transcription factor IKZF1 (IKAROS) acts as a critical regulator of lymphoid differentiation and is frequently deleted or mutated in B-cell precursor acute lymphoblastic leukemia. IKZF1 gene defects are associated with inferior treatment outcome in both childhood and adult B-cell precursor acute lymphoblastic leukemia and occur in more than 70% of BCR-ABL1-positive and BCR-ABL1-like cases of acute lymphoblastic leukemia. Over the past few years, much has been learned about the tumor suppressive function of IKZF1 during leukemia development and the molecular pathways that relate to its impact on treatment outcome. In this review, we provide a concise overview on the role of IKZF1 during normal lymphopoiesis and the pathways that contribute to leukemia pathogenesis as a consequence of altered IKZF1 function. Furthermore, we discuss different mechanisms by which IKZF1 alterations impose therapy resistance on leukemic cells, including enhanced cell adhesion and modulation of glucocorticoid response.
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Affiliation(s)
- René Marke
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Frank N van Leeuwen
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Blanca Scheijen
- Laboratory of Pediatric Oncology, Radboud University Medical Center, Nijmegen, the Netherlands .,Department of Pathology, Radboud University Medical Center; Radboud Institute for Molecular Life Sciences (RIMLS), Nijmegen, the Netherlands
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18
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Reuter N, Reichel A, Stilp AC, Scherer M, Stamminger T. SUMOylation of IE2p86 is required for efficient autorepression of the human cytomegalovirus major immediate-early promoter. J Gen Virol 2018; 99:369-378. [PMID: 29458530 DOI: 10.1099/jgv.0.001021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The human cytomegalovirus (HCMV) IE2p86 protein is pivotal for coordinated regulation of viral gene expression. Besides functioning as a promiscuous transactivator, IE2p86 is also known to negatively regulate its own transcription. This occurs via direct binding of IE2p86 to a 14-bp palindromic DNA element located between the TATA box and the transcription start site of the major immediate-early promoter (MIEP), which is referred to as the cis repression signal (CRS). However, the exact mechanism of IE2p86-based autorepression is still unclear. By testing a series of IE2p86 mutants in transient expression assays, we found that not only did a DNA binding-deficient mutant of IE2p86 fail to repress the MIEP, but SUMOylation-negative mutants also failed to repress it. This finding was further supported by infection studies with primary fibroblasts harbouring a MIEP-driven transgene as a reporter. Here, we observed that a recombinant HCMV expressing SUMOylation-negative IE2p86 was defective in transgene downregulation, in contrast to wild-type HCMV. Interestingly, however, a double-mutant virus in which both the SUMO acceptor sites and the SUMO interaction motif (SIM) of IE2p86 were inactivated regained the ability to silence the MIEP. This correlated with increased expression levels of the IE2 isoforms IE2p40 and IE2p60, suggesting that these late proteins may contribute to MIEP suppression, thus compensating for the loss of IE2p86 SUMOylation. In summary, our results show that autorepression of the MIEP is not only regulated by late isoforms of IE2, but also depends on posttranslational SUMO modification, revealing a novel mechanism to fine-tune the expression of this important viral gene region.
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Affiliation(s)
- Nina Reuter
- Institute of Clinical and Molecular Virology, Friedrich Alexander Universität Erlangen-Nürnberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - Anna Reichel
- Institute of Clinical and Molecular Virology, Friedrich Alexander Universität Erlangen-Nürnberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - Anne-Charlotte Stilp
- Institute of Clinical and Molecular Virology, Friedrich Alexander Universität Erlangen-Nürnberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - Myriam Scherer
- Institute of Virology, Ulm University Medical Center, Ulm, Germany
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19
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Abstract
In this review from Georgopoulos, the role of the IKAROS gene family in lymphocyte differentiation is discussed in light of recent studies on the lineage-specific transcriptional and epigenetic networks through which IKAROS proteins operate. Lymphocyte differentiation is set to produce myriad immune effector cells with the ability to respond to multitudinous foreign substances. The uniqueness of this developmental system lies in not only the great diversity of cellular functions that it can generate but also the ability of its differentiation intermediates and mature effector cells to expand upon demand, thereby providing lifelong immunity. Surprisingly, the goals of this developmental system are met by a relatively small group of DNA-binding transcription factors that work in concert to control the timing and magnitude of gene expression and fulfill the demands for cellular specialization, expansion, and maintenance. The cellular and molecular mechanisms through which these lineage-promoting transcription factors operate have been a focus of basic research in immunology. The mechanisms of development discerned in this effort are guiding clinical research on disorders with an immune cell base. Here, I focus on IKAROS, one of the earliest regulators of lymphoid lineage identity and a guardian of lymphocyte homeostasis.
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Affiliation(s)
- Katia Georgopoulos
- Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
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20
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Abstract
Post-translational protein modification by small ubiquitin-like modifier (SUMO), termed sumoylation, is an important mechanism in cellular responses to stress and one that appears to be upregulated in many cancers. Here, we examine the role of sumoylation in tumorigenesis as a possibly necessary safeguard that protects the stability and functionality of otherwise easily misregulated gene expression programmes and signalling pathways of cancer cells.
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Affiliation(s)
- Jacob-Sebastian Seeler
- Nuclear Organization and Oncogenesis Unit, INSERM U993, Institut Pasteur, 28 rue de Dr Roux, 75724 Paris Cedex 15, France
| | - Anne Dejean
- Nuclear Organization and Oncogenesis Unit, INSERM U993, Institut Pasteur, 28 rue de Dr Roux, 75724 Paris Cedex 15, France
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21
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Fan Y, Lu D. The Ikaros family of zinc-finger proteins. Acta Pharm Sin B 2016; 6:513-521. [PMID: 27818917 PMCID: PMC5071621 DOI: 10.1016/j.apsb.2016.06.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 05/20/2016] [Accepted: 05/24/2016] [Indexed: 12/21/2022] Open
Abstract
Ikaros represents a zinc-finger protein family important for lymphocyte development and certain other physiological processes. The number of family members is large, with alternative splicing producing various additional isoforms from each of the five homologous genes in the family. The functional forms of Ikaros proteins could be even more diverse due to protein–protein interactions readily established between family members. Emerging evidence suggests that targeting Ikaros proteins is feasible and effective in therapeutic applications, although the exact roles of Ikaros proteins remain elusive within the intricate regulatory networks in which they are involved. In this review we collect existing knowledge as to the functions, regulatory pathways, and molecular mechanisms of this family of proteins in an attempt to gain a better understanding through the comparison of activities and interactions among family members.
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22
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Apostolov A, Litim-Mecheri I, Oravecz A, Goepp M, Kirstetter P, Marchal P, Ittel A, Mauvieux L, Chan S, Kastner P. Sumoylation Inhibits the Growth Suppressive Properties of Ikaros. PLoS One 2016; 11:e0157767. [PMID: 27315244 PMCID: PMC4912065 DOI: 10.1371/journal.pone.0157767] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 06/03/2016] [Indexed: 01/01/2023] Open
Abstract
The Ikaros transcription factor is a tumor suppressor that is also important for lymphocyte development. How post-translational modifications influence Ikaros function remains partially understood. We show that Ikaros undergoes sumoylation in developing T cells that correspond to mono-, bi- or poly-sumoylation by SUMO1 and/or SUMO2/3 on three lysine residues (K58, K240 and K425). Sumoylation occurs in the nucleus and requires DNA binding by Ikaros. Sumoylated Ikaros is less effective than unsumoylated forms at inhibiting the expansion of murine leukemic cells, and Ikaros sumoylation is abundant in human B-cell acute lymphoblastic leukemic cells, but not in healthy peripheral blood leukocytes. Our results suggest that sumoylation may be important in modulating the tumor suppressor function of Ikaros.
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Affiliation(s)
- Apostol Apostolov
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
| | - Isma Litim-Mecheri
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
| | - Attila Oravecz
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
| | - Marie Goepp
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
| | - Peggy Kirstetter
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
| | - Patricia Marchal
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
| | - Antoine Ittel
- Laboratoire d’Hématologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- Laboratoire d’Hématologie Cellulaire, EA 3430, Institut d’Hématologie et d’Immunologie, Faculté de Médecine de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Université de Strasbourg, Strasbourg, France
| | - Laurent Mauvieux
- Laboratoire d’Hématologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- Laboratoire d’Hématologie Cellulaire, EA 3430, Institut d’Hématologie et d’Immunologie, Faculté de Médecine de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Université de Strasbourg, Strasbourg, France
| | - Susan Chan
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
| | - Philippe Kastner
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
- Faculté de Médecine, Université de Strasbourg, Strasbourg, France
- * E-mail:
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23
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Cho SJ, Kang H, Kim MY, Lee JE, Kim SJ, Nam SY, Kim JY, Kim HS, Pyo S, Yang KH. Site-Specific Phosphorylation of Ikaros Induced by Low-Dose Ionizing Radiation Regulates Cell Cycle Progression of B Lymphoblast Through CK2 and AKT Activation. Int J Radiat Oncol Biol Phys 2016; 94:1207-18. [DOI: 10.1016/j.ijrobp.2016.01.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 12/30/2015] [Accepted: 01/06/2016] [Indexed: 11/17/2022]
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Moriuchi T, Kuroda M, Kusumoto F, Osumi T, Hirose F. Lamin A reassembly at the end of mitosis is regulated by its SUMO-interacting motif. Exp Cell Res 2016; 342:83-94. [DOI: 10.1016/j.yexcr.2016.02.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Revised: 02/22/2016] [Accepted: 02/23/2016] [Indexed: 02/01/2023]
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25
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Wang H, Song C, Ding Y, Pan X, Ge Z, Tan BH, Gowda C, Sachdev M, Muthusami S, Ouyang H, Lai L, Francis OL, Morris CL, Abdel-Azim H, Dorsam G, Xiang M, Payne KJ, Dovat S. Transcriptional Regulation of JARID1B/KDM5B Histone Demethylase by Ikaros, Histone Deacetylase 1 (HDAC1), and Casein Kinase 2 (CK2) in B-cell Acute Lymphoblastic Leukemia. J Biol Chem 2015; 291:4004-18. [PMID: 26655717 DOI: 10.1074/jbc.m115.679332] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Indexed: 12/26/2022] Open
Abstract
Impaired function of the Ikaros (IKZF1) protein is associated with the development of high-risk B-cell precursor acute lymphoblastic leukemia (B-ALL). The mechanisms of Ikaros tumor suppressor activity in leukemia are unknown. Ikaros binds to the upstream regulatory elements of its target genes and regulates their transcription via chromatin remodeling. Here, we report that Ikaros represses transcription of the histone H3K4 demethylase, JARID1B (KDM5B). Transcriptional repression of JARID1B is associated with increased global levels of H3K4 trimethylation. Ikaros-mediated repression of JARID1B is dependent on the activity of the histone deacetylase, HDAC1, which binds to the upstream regulatory element of JARID1B in complex with Ikaros. In leukemia, JARID1B is overexpressed, and its inhibition results in cellular growth arrest. Ikaros-mediated repression of JARID1B in leukemia is impaired by pro-oncogenic casein kinase 2 (CK2). Inhibition of CK2 results in increased binding of the Ikaros-HDAC1 complex to the promoter of JARID1B, with increased formation of trimethylated histone H3 lysine 27 and decreased histone H3 Lys-9 acetylation. In cases of high-risk B-ALL that carry deletion of one Ikaros (IKZF1) allele, targeted inhibition of CK2 restores Ikaros binding to the JARID1B promoter and repression of JARID1B. In summary, the presented data suggest a mechanism through which Ikaros and HDAC1 regulate the epigenetic signature in leukemia: via regulation of JARID1B transcription. The presented data identify JARID1B as a novel therapeutic target in B-ALL and provide a rationale for the use of CK2 inhibitors in the treatment of high-risk B-ALL.
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Affiliation(s)
- Haijun Wang
- From the Department of Pathology, Xinxiang Medical University, Xinxiang 453003, Henan, China, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Chunhua Song
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Yali Ding
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Xiaokang Pan
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Zheng Ge
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Bi-Hua Tan
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Chandrika Gowda
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Mansi Sachdev
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Sunil Muthusami
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
| | - Hongsheng Ouyang
- From the Department of Pathology, Xinxiang Medical University, Xinxiang 453003, Henan, China
| | - Liangxue Lai
- From the Department of Pathology, Xinxiang Medical University, Xinxiang 453003, Henan, China
| | | | | | - Hisham Abdel-Azim
- the Division of Hematology, Oncology, and Blood and Marrow Transplantation, Children's Hospital Los Angeles, University of Southern California Keck School of Medicine, Los Angeles, California 90027
| | - Glenn Dorsam
- North Dakota State University, Fargo, North Dakota 58108, and
| | - Meixian Xiang
- the College of Pharmacy, South-Central University for Nationalities, Wuhan 430074, China
| | | | - Sinisa Dovat
- Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033,
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Song C, Gowda C, Pan X, Ding Y, Tong Y, Tan BH, Wang H, Muthusami S, Ge Z, Sachdev M, Amin SG, Desai D, Gowda K, Gowda R, Robertson GP, Schjerven H, Muschen M, Payne KJ, Dovat S. Targeting casein kinase II restores Ikaros tumor suppressor activity and demonstrates therapeutic efficacy in high-risk leukemia. Blood 2015; 126:1813-22. [PMID: 26219304 PMCID: PMC4600018 DOI: 10.1182/blood-2015-06-651505] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 07/16/2015] [Indexed: 12/13/2022] Open
Abstract
Ikaros (IKZF1) is a tumor suppressor that binds DNA and regulates expression of its target genes. The mechanism of Ikaros activity as a tumor suppressor and the regulation of Ikaros function in leukemia are unknown. Here, we demonstrate that Ikaros controls cellular proliferation by repressing expression of genes that promote cell cycle progression and the phosphatidylinositol-3 kinase (PI3K) pathway. We show that Ikaros function is impaired by the pro-oncogenic casein kinase II (CK2), and that CK2 is overexpressed in leukemia. CK2 inhibition restores Ikaros function as transcriptional repressor of cell cycle and PI3K pathway genes, resulting in an antileukemia effect. In high-risk leukemia where one IKZF1 allele has been deleted, CK2 inhibition restores the transcriptional repressor function of the remaining wild-type IKZF1 allele. CK2 inhibition demonstrated a potent therapeutic effect in a panel of patient-derived primary high-risk B-cell acute lymphoblastic leukemia xenografts as indicated by prolonged survival and a reduction of leukemia burden. We demonstrate the efficacy of a novel therapeutic approach for high-risk leukemia: restoration of Ikaros tumor suppressor activity via inhibition of CK2. These results provide a rationale for the use of CK2 inhibitors in clinical trials for high-risk leukemia, including cases with deletion of one IKZF1 allele.
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Affiliation(s)
- Chunhua Song
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Chandrika Gowda
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Xiaokang Pan
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Yali Ding
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Yongqing Tong
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Bi-Hua Tan
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Haijun Wang
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Sunil Muthusami
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Zheng Ge
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA; Department of Hematology, The First Affiliated Hospital of Nanjing Medical University, Jiangsu Province Hospital, Nanjing, China
| | - Mansi Sachdev
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
| | - Shantu G Amin
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA
| | - Dhimant Desai
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA
| | - Krishne Gowda
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA
| | - Raghavendra Gowda
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA
| | - Gavin P Robertson
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA
| | - Hilde Schjerven
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA; and
| | - Markus Muschen
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA; and
| | - Kimberly J Payne
- Department of Pathology and Human Anatomy, Loma Linda University, Loma Linda, CA
| | - Sinisa Dovat
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA
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SUMOylation-disrupting WAS mutation converts WASp from a transcriptional activator to a repressor of NF-κB response genes in T cells. Blood 2015; 126:1670-82. [PMID: 26261240 DOI: 10.1182/blood-2015-05-646182] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 08/08/2015] [Indexed: 11/20/2022] Open
Abstract
In Wiskott-Aldrich syndrome (WAS), immunodeficiency and autoimmunity often comanifest, yet how WAS mutations misregulate chromatin-signaling in Thelper (TH) cells favoring development of auto-inflammation over protective immunity is unclear. Previously, we identified an essential promoter-specific, coactivator role of nuclear-WASp in TH1 gene transcription. Here we identify small ubiquitin-related modifier (SUMO)ylation as a novel posttranslational modification of WASp, impairment of which converts nuclear-WASp from a transcriptional coactivator to a corepressor of nuclear factor (NF)-κB response genes in human (TH)1-differentiating cells. V75M, one of many disease-causing mutations occurring in SUMO*motif (72-ψψψψKDxxxxSY-83) of WASp, compromises WASp-SUMOylation, associates with COMMD1 to attenuate NF-κB signaling, and recruits histone deacetylases-6 (HDAC6) to p300-marked promoters of NF-κB response genes that pattern immunity but not inflammation. Consequently, proteins mediating adaptive immunity (IFNG, STAT1, TLR1) are deficient, whereas those mediating auto-inflammation (GM-CSF, TNFAIP2, IL-1β) are paradoxically increased in TH1 cells expressing SUMOylation-deficient WASp. Moreover, SUMOylation-deficient WASp favors ectopic development of the TH17-like phenotype (↑IL17A, IL21, IL22, IL23R, RORC, and CSF2) under TH1-skewing conditions, suggesting a role for WASp in modulating TH1/TH17 plasticity. Notably, pan-histone deacetylase inhibitors lift promoter-specific repression imposed by SUMOylation-deficient WASp and restore misregulated gene expression. Our findings uncovering a SUMOylation-based mechanism controlling WASp's dichotomous roles in transcription may have implications for personalized therapy for patients carrying mutations that perturb WASp-SUMOylation.
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Wang H, Song C, Gurel Z, Song N, Ma J, Ouyang H, Lai L, Payne KJ, Dovat S. Protein phosphatase 1 (PP1) and Casein Kinase II (CK2) regulate Ikaros-mediated repression of TdT in thymocytes and T-cell leukemia. Pediatr Blood Cancer 2014; 61:2230-5. [PMID: 25214003 PMCID: PMC4205270 DOI: 10.1002/pbc.25221] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 07/20/2014] [Indexed: 12/16/2022]
Abstract
BACKGROUND Ikaros is a DNA-binding protein that acts as master-regulator of hematopoiesis and a tumor suppressor. In thymocytes and T-cell leukemia, Ikaros negatively regulates transcription of terminal deoxynucleotide transferase (TdT), a key protein in lymphocyte differentiation. The signaling pathways that regulate Ikaros-mediated repression of TdT are unknown. Our previous work identified Casein Kinase II (CK2) and Protein Phosphatase 1 (PP1) as regulators of Ikaros DNA binding activity. Here, we investigated the role of PP1 and CK2 in regulating Ikaros-mediated control of TdT expression. PROCEDURES Ikaros phosphomimetic and phosphoresistant mutants and specific CK2 and PP1 inhibitors were used in combination with quantitative chromatin immunoprecipitation (qChIP) and quantitative reverse transcriptase-PCR (q RT-PCR) assays to evaluate the role of CK2 and PP1 in regulating the ability of Ikaros to bind the TdT promoter and to regulate TdT expression. RESULTS We demonstrate that phosphorylation of Ikaros by pro-oncogenic CK2 decreases Ikaros binding to the promoter of the TdT gene and reduces the ability of Ikaros to repress TdT expression during thymocyte differentiation. CK2 inhibition and PP1 activity restore Ikaros DNA-binding affinity toward the TdT promoter, as well as Ikaros-mediated transcriptional repression of TdT in primary thymocytes and in leukemia. CONCLUSION These data establish that PP1 and CK2 signal transduction pathways regulate Ikaros-mediated repression of TdT in thymocytes and leukemia. These findings reveal that PP1 and CK2 have opposing effects on Ikaros-mediated repression of TdT and establish novel roles for PP1 and CK2 signaling in thymocyte differentiation and leukemia.
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Affiliation(s)
- Haijun Wang
- School of Pharmacology, Wenzhou Medical University, Wenzhou 325035, China,Pennsylvania State University College of Medicine, Hershey, PA 17033,College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Chunhua Song
- Pennsylvania State University College of Medicine, Hershey, PA 17033
| | | | - Na Song
- School of Pharmacology, Wenzhou Medical University, Wenzhou 325035, China
| | - Jisheng Ma
- School of Pharmacology, Wenzhou Medical University, Wenzhou 325035, China
| | - Hongsheng Ouyang
- College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Liangxue Lai
- College of Animal Sciences, Jilin University, Changchun 130062, China
| | | | - Sinisa Dovat
- Pennsylvania State University College of Medicine, Hershey, PA 17033,Corresponding author: Sinisa Dovat, MD PhD, Division of Pediatric Hematology/Oncology, Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA 17033, Phone: 717-531-6012, FAX: 717-531-4789,
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29
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Weaver KL, Alves-Guerra MC, Jin K, Wang Z, Han X, Ranganathan P, Zhu X, DaSilva T, Liu W, Ratti F, Demarest RM, Tzimas C, Rice M, Vasquez-Del Carpio R, Dahmane N, Robbins DJ, Capobianco AJ. NACK is an integral component of the Notch transcriptional activation complex and is critical for development and tumorigenesis. Cancer Res 2014; 74:4741-51. [PMID: 25038227 DOI: 10.1158/0008-5472.can-14-1547] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The Notch signaling pathway governs many distinct cellular processes by regulating transcriptional programs. The transcriptional response initiated by Notch is highly cell context dependent, indicating that multiple factors influence Notch target gene selection and activity. However, the mechanism by which Notch drives target gene transcription is not well understood. Herein, we identify and characterize a novel Notch-interacting protein, Notch activation complex kinase (NACK), which acts as a Notch transcriptional coactivator. We show that NACK associates with the Notch transcriptional activation complex on DNA, mediates Notch transcriptional activity, and is required for Notch-mediated tumorigenesis. We demonstrate that Notch1 and NACK are coexpressed during mouse development and that homozygous loss of NACK is embryonic lethal. Finally, we show that NACK is also a Notch target gene, establishing a feed-forward loop. Thus, our data indicate that NACK is a key component of the Notch transcriptional complex and is an essential regulator of Notch-mediated tumorigenesis and development.
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Affiliation(s)
- Kelly L Weaver
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Marie-Clotilde Alves-Guerra
- Inserm U1016, Institut Cochin, Paris, France. CNRS, UMR 8104, Paris, France. Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Ke Jin
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Zhiqiang Wang
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Xiaoqing Han
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Prathibha Ranganathan
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Xiaoxia Zhu
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Thiago DaSilva
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Wei Liu
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida. Department of Hepatobiliary Surgery, Southwest Hospital, Third Military Medical University, Chonqing, China
| | - Francesca Ratti
- Ecole Normale Supérieure de Lyon, CNRS UMR 5239, Equipe de Différenciation Neuromusculaire, Lyon, France
| | - Renee M Demarest
- Rowan University School of Osteopathic Medicine, Department of Molecular Biology, Stratford, NJ
| | - Cristos Tzimas
- Molecular Biology Division, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Meghan Rice
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | | | - Nadia Dahmane
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - David J Robbins
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Anthony J Capobianco
- Molecular Oncology Program, Division of Surgical Oncology, Dewitt Daughtry Family Department of Surgery, and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida.
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Satpathy S, Guérillon C, Kim TS, Bigot N, Thakur S, Bonni S, Riabowol K, Pedeux R. SUMOylation of the ING1b tumor suppressor regulates gene transcription. Carcinogenesis 2014; 35:2214-23. [PMID: 24903338 DOI: 10.1093/carcin/bgu126] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The INhibitor of Growth (ING) proteins are encoded as multiple isoforms in five ING genes (ING1 -5) and act as type II tumor suppressors. They are growth inhibitory when overexpressed and are frequently mislocalized or downregulated in several forms of cancer. ING1 and ING2 are stoichiometric members of histone deacetylase complexes, whereas ING3-5 are stoichiometric components of different histone acetyltransferase complexes. The INGs target these complexes to histone marks, thus acting as epigenetic regulators. ING proteins affect angiogenesis, apoptosis, DNA repair, metastasis and senescence, but how the proteins themselves are regulated is not yet clear. Here, we find a small ubiquitin-like modification (SUMOylation) of the ING1b protein and identify lysine 193 (K193) as the preferred ING1b SUMO acceptor site. We also show that PIAS4 is the E3 SUMO ligase responsible for ING1b SUMOylation on K193. Sequence alignment reveals that the SUMO consensus site on ING1b contains a phosphorylation-dependent SUMOylation motif (PDSM) and our data indicate that the SUMOylation on K193 is enhanced by the S199D phosphomimic mutant. Using an ING1b protein mutated at the major SUMOylation site (ING1b E195A), we further demonstrate that ING1b SUMOylation regulates the binding of ING1b to the ISG15 and DGCR8 promoters, consequently regulating ISG15 and DGCR8 transcription. These results suggest a role for ING1b SUMOylation in the regulation of gene transcription.
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Affiliation(s)
- Shankha Satpathy
- Department of Biochemistry and Molecular Biology, Southern Alberta Cancer Research Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada, Present address: The Novo Nordisk Foundation Center for Protein Research, Copenhagen, Denmark
| | - Claire Guérillon
- INSERM U917, Microenvironnement et Cancer, 350043 Rennes, France, Université de Rennes 1, 350043 Rennes, France and
| | - Tae-Sun Kim
- Department of Biochemistry and Molecular Biology, Southern Alberta Cancer Research Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Nicolas Bigot
- INSERM U917, Microenvironnement et Cancer, 350043 Rennes, France, Université de Rennes 1, 350043 Rennes, France and
| | - Satbir Thakur
- INSERM U917, Microenvironnement et Cancer, 350043 Rennes, France
| | - Shirin Bonni
- INSERM U917, Microenvironnement et Cancer, 350043 Rennes, France
| | - Karl Riabowol
- Department of Biochemistry and Molecular Biology, Southern Alberta Cancer Research Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada,
| | - Rémy Pedeux
- INSERM U917, Microenvironnement et Cancer, 350043 Rennes, France
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Epstein-Barr virus utilizes Ikaros in regulating its latent-lytic switch in B cells. J Virol 2014; 88:4811-27. [PMID: 24522918 DOI: 10.1128/jvi.03706-13] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
UNLABELLED Ikaros is a zinc finger DNA-binding protein that regulates chromatin remodeling and the expression of genes involved in the cell cycle, apoptosis, and Notch signaling. It is a master regulator of lymphocyte differentiation and functions as a tumor suppressor in acute lymphoblastic leukemia. Nevertheless, no previous reports described effects of Ikaros on the life cycle of any human lymphotropic virus. Here, we demonstrate that full-length Ikaros (IK-1) functions as a major factor in the maintenance of viral latency in Epstein-Barr virus (EBV)-positive Burkitt's lymphoma Sal and MutuI cell lines. Either silencing of Ikaros expression by small hairpin RNA (shRNA) knockdown or ectopic expression of a non-DNA-binding isoform induced lytic gene expression. These effects synergized with other lytic inducers of EBV, including transforming growth factor β (TGF-β) and the hypoxia mimic desferrioxamine. Data from chromatin immunoprecipitation (ChIP)-quantitative PCR (qPCR) and ChIP-sequencing (ChIP-seq) analyses indicated that Ikaros did not bind to either of the EBV immediate early genes BZLF1 and BRLF1. Rather, Ikaros affected the expression of Oct-2 and Bcl-6, other transcription factors that directly inhibit EBV reactivation and plasma cell differentiation, respectively. IK-1 also complexed with the EBV immediate early R protein in coimmunoprecipitation assays and partially colocalized with R within cells. The presence of R alleviated IK-1-mediated transcriptional repression, with IK-1 then cooperating with Z and R to enhance lytic gene expression. Thus, we conclude that Ikaros plays distinct roles at different stages of EBV's life cycle: it contributes to maintaining latency via indirect mechanisms, and it may also synergize with Z and R to enhance lytic replication through direct association with R and/or R-induced alterations in Ikaros' functional activities via cellular signaling pathways. IMPORTANCE This is the first report showing that the cellular protein Ikaros, a known master regulator of hematopoiesis and critical tumor suppressor in acute lymphoblastic leukemia, also plays important roles in the life cycle of Epstein-Barr virus in B cells.
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Schwickert TA, Tagoh H, Gültekin S, Dakic A, Axelsson E, Minnich M, Ebert A, Werner B, Roth M, Cimmino L, Dickins RA, Zuber J, Jaritz M, Busslinger M. Stage-specific control of early B cell development by the transcription factor Ikaros. Nat Immunol 2014; 15:283-93. [PMID: 24509509 DOI: 10.1038/ni.2828] [Citation(s) in RCA: 156] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Accepted: 01/13/2014] [Indexed: 12/14/2022]
Abstract
The transcription factor Ikaros is an essential regulator of lymphopoiesis. Here we studied its B cell-specific function by conditional inactivation of the gene encoding Ikaros (Ikzf1) in pro-B cells. B cell development was arrested at an aberrant 'pro-B cell' stage characterized by increased cell adhesion and loss of signaling via the pre-B cell signaling complex (pre-BCR). Ikaros activated genes encoding signal transducers of the pre-BCR and repressed genes involved in the downregulation of pre-BCR signaling and upregulation of the integrin signaling pathway. Unexpectedly, derepression of expression of the transcription factor Aiolos did not compensate for the loss of Ikaros in pro-B cells. Ikaros induced or suppressed active chromatin at regulatory elements of activated or repressed target genes. Notably, binding of Ikaros and expression of its target genes were dynamically regulated at distinct stages of early B lymphopoiesis.
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Affiliation(s)
- Tanja A Schwickert
- 1] Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria. [2]
| | - Hiromi Tagoh
- 1] Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria. [2]
| | - Sinan Gültekin
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Aleksandar Dakic
- 1] Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria. [2]
| | - Elin Axelsson
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Martina Minnich
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Anja Ebert
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Barbara Werner
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Mareike Roth
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Luisa Cimmino
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Ross A Dickins
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Johannes Zuber
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Markus Jaritz
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Meinrad Busslinger
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
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33
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Filtz TM, Vogel WK, Leid M. Regulation of transcription factor activity by interconnected post-translational modifications. Trends Pharmacol Sci 2013; 35:76-85. [PMID: 24388790 DOI: 10.1016/j.tips.2013.11.005] [Citation(s) in RCA: 152] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 11/20/2013] [Accepted: 11/25/2013] [Indexed: 01/03/2023]
Abstract
Transcription factors comprise just over 7% of the human proteome and serve as gatekeepers of cellular function, integrating external signal information into gene expression programs that reconfigure cellular physiology at the most basic levels. Surface-initiated cell signaling pathways converge on transcription factors, decorating these proteins with an array of post-translational modifications (PTMs) that are often interdependent, being linked in time, space, and combinatorial function. These PTMs orchestrate every activity of a transcription factor over its entire lifespan--from subcellular localization to protein-protein interactions, sequence-specific DNA binding, transcriptional regulatory activity, and protein stability--and play key roles in the epigenetic regulation of gene expression. The multitude of PTMs of transcription factors also offers numerous potential points of intervention for development of therapeutic agents to treat a wide spectrum of diseases. We review PTMs most commonly targeting transcription factors, focusing on recent reports of sequential and linked PTMs of individual factors.
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Affiliation(s)
- Theresa M Filtz
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331, USA.
| | - Walter K Vogel
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331, USA
| | - Mark Leid
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331, USA; Department of Integrative Biosciences, Oregon Health & Science University, Portland, OR 97239, USA.
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Abstract
A major challenge in nuclear organization is the packaging of DNA into dynamic chromatin structures that can respond to changes in the transcriptional requirements of the cell. Posttranslational protein modifications, of histones and other chromatin-associated factors, are essential regulators of chromatin dynamics. In this Review, we summarize studies demonstrating that posttranslational modification of proteins by small ubiquitin-related modifiers (SUMOs) regulates chromatin structure and function at multiple levels and through a variety of mechanisms to influence gene expression and maintain genome integrity.
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Affiliation(s)
- Caelin Cubeñas-Potts
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
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Frank S, Peters MA, Wehmeyer C, Strietholt S, Koers-Wunrau C, Bertrand J, Heitzmann M, Hillmann A, Sherwood J, Seyfert C, Gay S, Pap T. Regulation of matrixmetalloproteinase-3 and matrixmetalloproteinase-13 by SUMO-2/3 through the transcription factor NF-κB. Ann Rheum Dis 2013; 72:1874-81. [PMID: 23417988 DOI: 10.1136/annrheumdis-2012-202080] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE Based on previous data that have linked the small ubiquitin-like modifier-1 (SUMO-1) to the pathogenesis of rheumatoid arthritis (RA), we have investigated the expression of the highly homologous SUMO family members SUMO-2/3 in human RA and in the human tumour necrosis factor α transgenic (hTNFtg) mouse model of RA and studied their role in regulating disease specific matrixmetalloproteinases (MMPs). METHODS Synovial tissue was obtained from RA and osteoarthritis (OA) patients and used for histological analyses as well as for the isolation of synovial fibroblasts (SFs). The expression of SUMO-2/3 in RA and OA patients as well as in hTNFtg and wild type mice was studied by PCR, western blot and immunostaining. SUMO-2/3 was knocked down using small interfering RNA in SFs, and TNF-α induced MMP production was determined by ELISA. Activation of nuclear factor-κB (NF-κB) was determined by a luciferase activity assay and a transcription factor assay in the presence of the NF-κB inhibitor BAY 11-7082. RESULTS Expression of SUMO-2 and to a lesser extent of SUMO-3 was higher in RA tissues and RASFs compared with OA controls. Similarly, there was increased expression of SUMO-2 in the synovium and in SFs of hTNFtg mice compared with wild type animals. In vitro, the expression of SUMO-2 but not of SUMO-3 was induced by TNF-α. The knockdown of SUMO-2/3 significantly increased the TNF-α and interleukin (IL)-1β induced expression of MMP-3 and MMP-13, accompanied by increased NF-κB activity. Induction of MMP-3 and MMP-13 was inhibited by blockade of the NF-κB pathway. TNF-α and IL-1β mediated MMP-1 expression was not regulated by SUMO-2/3. CONCLUSIONS Collectively, we show that despite their high homology, SUMO-2/3 are differentially regulated by TNF-α and selectively control TNF-α mediated MMP expression via the NF-κB pathway. Therefore, we hypothesise that SUMO-2 contributes to the specific activation of RASF.
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Affiliation(s)
- Svetlana Frank
- Institute of Experimental Musculoskeletal Medicine, University Hospital Muenster, , Muenster, Germany
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AF10 plays a key role in the survival of uncommitted hematopoietic cells. PLoS One 2012; 7:e51626. [PMID: 23284727 PMCID: PMC3526614 DOI: 10.1371/journal.pone.0051626] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Accepted: 11/02/2012] [Indexed: 12/11/2022] Open
Abstract
Hematopoiesis is a complex process regulated by both cell intrinsic and cell extrinsic factors. Alterations in the expression of critical genes during hematopoiesis can modify the balance between stem cell differentiation and proliferation, and may ultimately give rise to leukemia and other diseases. AF10 is a transcription factor that has been implicated in the development of leukemia following chromosomal rearrangements between the AF10 gene and one of at least two other genes, MLL and CALM. The link between AF10 and leukemia, together with the known interactions between AF10 and hematopoietic regulators, suggests that AF10 may be important in hematopoiesis and in leukemic transformation. Here we show that AF10 is important for proper hematopoietic differentiation. The induction of hematopoietic differentiation in both human hematopoietic cell lines and murine total bone marrow cells triggers a decrease of AF10 mRNA and protein levels, particularly in stem cells and multipotent progenitors. Gain- and loss-of-function studies demonstrate that over- or under-expression of AF10 leads to apoptotic cell death in stem cells and multipotent progenitors. We conclude that AF10 plays a key role in the maintenance of multipotent hematopoietic cells.
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SUMOylation regulates the transcriptional repression activity of FOG-2 and its association with GATA-4. PLoS One 2012; 7:e50637. [PMID: 23226341 PMCID: PMC3511347 DOI: 10.1371/journal.pone.0050637] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 10/23/2012] [Indexed: 11/25/2022] Open
Abstract
Friend of GATA 2 (FOG-2), a co-factor of several GATA transcription factors (GATA-4, -5 and 6), is a critical regulator of coronary vessel formation and heart morphogenesis. Here we demonstrate that FOG-2 is SUMOylated and that this modification modulates its transcriptional activity. FOG-2 SUMOylation occurs at four lysine residues (K312, 471, 915, 955). Three of these residues are part of the characteristic SUMO consensus site (ψKXE), while K955 is found in the less frequent TKXE motif. Absence of SUMOylation did not affect FOG-2′s nuclear localization. However, mutation of the FOG-2 SUMOylation sites, or de-SUMOylation, with SENP-1 or SENP-8 resulted in stronger transcriptional repression activity in both heterologous cells and cardiomyocytes. Conversely, increased FOG-2 SUMOylation by overexpression of SUMO-1 or expression of a SUMO-1-FOG-2 fusion protein rendered FOG-2 incapable of repressing GATA-4-mediated activation of the B-type natriuretic peptide (BNP) promoter. Moreover, we demonstrate both increased interaction between a FOG-2 SUMO mutant and GATA-4 and enhanced SUMOylation of wild-type FOG-2 by co-expression of GATA-4. These data suggest a new dynamics in which GATA-4 may alter the activity of FOG-2 by influencing its SUMOylation status.
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Zhang LJ, Vogel WK, Liu X, Topark-Ngarm A, Arbogast BL, Maier CS, Filtz TM, Leid M. Coordinated regulation of transcription factor Bcl11b activity in thymocytes by the mitogen-activated protein kinase (MAPK) pathways and protein sumoylation. J Biol Chem 2012; 287:26971-88. [PMID: 22700985 DOI: 10.1074/jbc.m112.344176] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The transcriptional regulatory protein Bcl11b is essential for T-cell development. We have discovered a dynamic, MAPK-regulated pathway involving sequential, linked, and reversible post-translational modifications of Bcl11b in thymocytes. MAPK-mediated phosphorylation of Bcl11b was coupled to its rapid desumoylation, which was followed by a subsequent cycle of dephosphorylation and resumoylation. Additionally and notably, we report the first instance of direct identification by mass spectrometry of a site of small ubiquitin-like modifier (SUMO) adduction, Lys-679 of Bcl11b, in a protein isolated from a native, mammalian cell. Sumoylation of Bcl11b resulted in recruitment of the transcriptional co-activator p300 to a Bcl11b-repressed promoter with subsequent induction of transcription. Prolonged treatment of native thymocytes with phorbol 12,13-dibutyrate together with the calcium ionophore A23187 also promoted ubiquitination and proteasomal degradation of Bcl11b, providing a mechanism for signal termination. A Bcl11b phospho-deSUMO switch was identified, the basis of which was phosphorylation-dependent recruitment of the SUMO hydrolase SENP1 to phospho-Bcl11b, coupled to hydrolysis of SUMO-Bcl11b. These results define a regulatory pathway in thymocytes that includes the MAPK pathways and upstream signaling components, Bcl11b and the associated nucleosome remodeling and deacetylation (NuRD) complex, SENP proteins, the Bcl11b protein phosphatase 6, the sumoylation machinery, the histone acetyltransferase p300, and downstream transcriptional machinery. This pathway appears to facilitate derepression of repressed Bcl11b target genes as immature thymocytes initiate differentiation programs, biochemically linking MAPK signaling with the latter stages of T-cell development.
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Affiliation(s)
- Ling-juan Zhang
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, Oregon 97331, USA
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Abstract
The Ikzf1 gene encodes Ikaros-a DNA-binding zinc finger protein. Ikaros functions as a regulator of gene expression and chromatin remodeling. The biological roles of Ikaros include regulating the development and function of the immune system and acting as a master regulator of hematopoietic differentiation. Genomic profiling studies identified Ikzf1 as an important tumor suppressor in acute lymphoblastic leukemia (ALL), particularly in ALL that is associated with poor prognosis. This review summarizes currently available data regarding the structure and function of Ikaros, the clinical relevance of genetic inactivation of Ikzf1, and signal transduction pathways that regulate Ikaros function.
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The SUMO E3 ligase Siz2 exerts a locus-dependent effect on gene silencing in Saccharomyces cerevisiae. EUKARYOTIC CELL 2012; 11:452-62. [PMID: 22345352 DOI: 10.1128/ec.05243-11] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In the yeast Saccharomyces cerevisiae, the two silent mating-type loci and subtelomeric regions are subjected to a well-characterized form of gene silencing. Establishment of silencing involves the formation of a distinct chromatin state that is refractory to transcription. This structure is established by the action of silent information regulator proteins (Sir2, Sir3, and Sir4) that bind to nucleosomes and initiate the deacetylation of multiple lysine residues in histones H3 and H4. Sir2 protein is a conserved histone deacetylase that is critical for mating-type and telomeric silencing, as well as a Sir3/4-independent form of silencing observed within the ribosomal DNA (rDNA) repeat locus. We report here that sumoylation plays an important role in regulating gene silencing. We show that increased dosage of SIZ2, a SUMO (small ubiquitin-related modifier) ligase, is antagonistic to gene silencing and that this effect is enhanced by mutation of ESC1, whose product is involved in tethering telomeres to the nuclear periphery. We present evidence indicating that an elevated SIZ2 dosage causes reduced binding of Sir2 protein to telomeres. These data support the idea that sumoylation of specific substrates at the nuclear periphery regulates the availability of Sir2 protein at telomeres.
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Harnessing of the nucleosome-remodeling-deacetylase complex controls lymphocyte development and prevents leukemogenesis. Nat Immunol 2011; 13:86-94. [PMID: 22080921 PMCID: PMC3868219 DOI: 10.1038/ni.2150] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 09/24/2011] [Indexed: 12/11/2022]
Abstract
Cell fate decisions depend on the interplay between chromatin regulators and transcription factors. Here we show that activity of the Mi-2β nucleosome remodeling and deacetylase (NuRD) complex was controlled by the Ikaros family of lymphoid-lineage determining proteins. Ikaros, an integral component of the NuRD complex in lymphocytes, tethered this complex to active lymphoid differentiation genes. Loss in Ikaros DNA binding activity caused a local increase in Mi-2β chromatin remodeling and histone deacetylation and suppression of lymphoid gene expression. The NuRD complex also redistributed to transcriptionally poised non-Ikaros gene targets, involved in proliferation and metabolism, inducing their reactivation. Thus, release of NuRD from Ikaros regulation blocks lymphocyte maturation and mediates progression to a leukemic state by engaging functionally opposing epigenetic and genetic networks.
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Ikaros, CK2 kinase, and the road to leukemia. Mol Cell Biochem 2011; 356:201-7. [PMID: 21750978 DOI: 10.1007/s11010-011-0964-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 06/24/2011] [Indexed: 01/25/2023]
Abstract
Ikaros encodes a zinc finger protein that is essential for hematopoiesis and that acts as a tumor suppressor in leukemia. Ikaros function depends on its ability to localize to pericentromeric-heterochromatin (PC-HC). Ikaros protein binds to the upstream regulatory elements of target genes, aids in their recruitment to PC-HC, and regulates their transcription via chromatin remodeling. We identified four novel Ikaros phosphorylation sites that are phosphorylated by CK2 kinase. Using Ikaros phosphomimetic and phosphoresistant mutants of the CK2 phosphorylation sites, we demonstrate that (1) CK2-mediated phosphorylation inhibits Ikaros' localization to PC-HC; (2) dephosphorylation of Ikaros at CK2 sites increases its binding to the promoter of the terminal deoxynucleotidetransferase (TdT) gene, leading to TdT repression during thymocyte differentiation; and (3) hyperphosphorylation of Ikaros promotes its degradation by the ubiquitin/proteasome pathway. We show that Ikaros is dephosphorylated by Protein Phosphatase 1 (PP1) via interaction at a consensus PP1-binding motif, RVXF. Point mutations that abolish Ikaros-PP1 interaction result in functional changes in DNA-binding affinity and subcellular localization, similar to those observed in hyperphosphorylated Ikaros and/or Ikaros phosphomimetic mutants. Phosphoresistant Ikaros mutations at CK2 sites restored Ikaros' DNA-binding activity and localization to PC-HC and prevented accelerated Ikaros degradation. These results demonstrate the role of CK2 kinase in lymphocyte differentiation and in regulation of Ikaros' function, and suggest that CK2 promotes leukemogenesis by inhibiting the tumor suppressor activity of Ikaros. We propose a model whereby a balance between CK2 kinase and PP1 phosphatase is essential for normal lymphocyte differentiation and for the prevention of malignant transformation.
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Francis OL, Payne JL, Su RJ, Payne KJ. Regulator of myeloid differentiation and function: The secret life of Ikaros. World J Biol Chem 2011; 2:119-25. [PMID: 21765977 PMCID: PMC3135858 DOI: 10.4331/wjbc.v2.i6.119] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 05/02/2011] [Accepted: 05/09/2011] [Indexed: 02/05/2023] Open
Abstract
Ikaros (also known as Lyf-1) was initially described as a lymphoid-specific transcription factor. Although Ikaros has been shown to regulate hematopoietic stem cell renewal, as well as the development and function of cells from multiple hematopoietic lineages, including the myeloid lineage, Ikaros has primarily been studied in context of lymphoid development and malignancy. This review focuses on the role of Ikaros in myeloid cells. We address the importance of post-transcriptional regulation of Ikaros function; the emerging role of Ikaros in myeloid malignancy; Ikaros as a regulator of myeloid differentiation and function; and the selective expression of Ikaros isoform-x in cells with myeloid potential. We highlight the challenges of dissecting Ikaros function in lineage commitment decisions among lymphoid-myeloid progenitors that have emerged as a major myeloid differentiation pathway in recent studies, which leads to reconstruction of the traditional map of murine and human hematopoiesis.
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Affiliation(s)
- Olivia L Francis
- Olivia L Francis, Rui-Jun Su, Kimberly J Payne, Department of Pathology and Human Anatomy, Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Mortensen Hall 1st Floor, 11085 Campus St, Loma Linda, CA 9350, United States
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44
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Sellars M, Kastner P, Chan S. Ikaros in B cell development and function. World J Biol Chem 2011; 2:132-9. [PMID: 21765979 PMCID: PMC3135860 DOI: 10.4331/wjbc.v2.i6.132] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 06/18/2011] [Accepted: 06/23/2011] [Indexed: 02/05/2023] Open
Abstract
The zinc finger transcription factor, Ikaros, is a central regulator of hematopoiesis. It is required for the development of the earliest B cell progenitors and at later stages for VDJ recombination and B cell receptor expression. Mature B cells rely on Ikaros to set the activation threshold for various stimuli, and to choose the correct antibody isotype during class switch recombination. Thus, Ikaros contributes to nearly every level of B cell differentiation and function.
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Affiliation(s)
- Maclean Sellars
- MacLean Sellars, New York University School of Medicine, New York, NY 10016, United States
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45
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Bottardi S, Zmiri FA, Bourgoin V, Ross J, Mavoungou L, Milot E. Ikaros interacts with P-TEFb and cooperates with GATA-1 to enhance transcription elongation. Nucleic Acids Res 2011; 39:3505-19. [PMID: 21245044 PMCID: PMC3089448 DOI: 10.1093/nar/gkq1271] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Ikaros is associated with both gene transcriptional activation and repression in lymphocytes. Ikaros acts also as repressor of human γ-globin (huγ-) gene transcription in fetal and adult erythroid cells. Whether and eventually, how Ikaros can function as a transcriptional activator in erythroid cells remains poorly understood. Results presented herein demonstrate that Ikaros is a developmental-specific activator of huγ-gene expression in yolk sac erythroid cells. Molecular analysis in primary cells revealed that Ikaros interacts with Gata-1 and favors Brg1 recruitment to the human β-globin Locus Control Region and the huγ-promoters, supporting long-range chromatin interactions between these regions. Additionally, we demonstrate that Ikaros contributes to transcription initiation and elongation of the huγ-genes, since it is not only required for TBP and RNA Polymerase II (Pol II) assembly at the huγ-promoters but also for conversion of Pol II into the elongation-competent phosphorylated form. In agreement with the latter, we show that Ikaros interacts with Cyclin-dependent kinase 9 (Cdk9), which contributes to efficient transcription elongation by phosphorylating the C-terminal domain of the large subunit of Pol II on Serine 2, and favours Cdk9 recruitment to huγ-promoters. Our results show that Ikaros exerts dual functionality during gene activation, by promoting efficient transcription initiation and elongation.
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Affiliation(s)
- Stefania Bottardi
- Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital and Faculty of Medicine, University of Montreal, 5415 boulevard l'Assomption, Montreal, Quebec, Canada H1T 2M4
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Gómez-del Arco P, Kashiwagi M, Jackson AF, Naito T, Zhang J, Liu F, Kee B, Vooijs M, Radtke F, Redondo JM, Georgopoulos K. Alternative promoter usage at the Notch1 locus supports ligand-independent signaling in T cell development and leukemogenesis. Immunity 2010; 33:685-98. [PMID: 21093322 DOI: 10.1016/j.immuni.2010.11.008] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Revised: 08/12/2010] [Accepted: 09/15/2010] [Indexed: 01/20/2023]
Abstract
Loss of the transcription factor Ikaros is correlated with Notch receptor activation in T cell acute lymphoblastic leukemia (T-ALL). However, the mechanism remains unknown. We identified promoters in Notch1 that drove the expression of Notch1 proteins in the absence of a ligand. Ikaros bound to both canonical and alternative Notch1 promoters and its loss increased permissive chromatin, facilitating recruitment of transcription regulators. At early stages of leukemogenesis, increased basal expression from the canonical and 5'-alternative promoters initiated a feedback loop, augmenting Notch1 signaling. Ikaros also repressed intragenic promoters for ligand-independent Notch1 proteins that are cryptic in wild-type cells, poised in preleukemic cells, and active in leukemic cells. Only ligand-independent Notch1 isoforms were required for Ikaros-mediated leukemogenesis. Notch1 alternative-promoter usage was observed during T cell development and T-ALL progression. Thus, a network of epigenetic and transcriptional regulators controls conventional and unconventional Notch signaling during normal development and leukemogenesis.
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Affiliation(s)
- Pablo Gómez-del Arco
- Vascular Biology and Inflammation Department, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 28029, Spain
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Cheema A, Knights CD, Rao M, Catania J, Perez R, Simons B, Dakshanamurthy S, Kolukula VK, Tilli M, Furth PA, Albanese C, Avantaggiati ML. Functional mimicry of the acetylated C-terminal tail of p53 by a SUMO-1 acetylated domain, SAD. J Cell Physiol 2010; 225:371-84. [PMID: 20458745 DOI: 10.1002/jcp.22224] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The ubiquitin-like molecule, SUMO-1, a small protein essential for a variety of biological processes, is covalently conjugated to many intracellular proteins, especially to regulatory components of the transcriptional machinery, such as histones and transcription factors. Sumoylation provides either a stimulatory or an inhibitory signal for proliferation and for transcription, but the molecular mechanisms by which SUMO-1 achieves such versatility of effects are incompletely defined. The tumor suppressor and transcription regulator p53 is a relevant SUMO-1 target. Particularly, the C-terminal tail of p53 undergoes both sumoylation and acetylation. While the effects of sumoylation are still controversial, acetylation modifies p53 interaction with chromatin embedded promoters, and enforces p53 apoptotic activity. In this study, we show that the N-terminal region of SUMO-1 might functionally mimic this activity of the p53 C-terminal tail. We found that this SUMO-1 domain possesses similarity with the C-terminal acetylable p53 tail as well as with acetylable domains of other transcription factors. SUMO-1 is, indeed, acetylated when conjugated to its substrates and to p53. In the acetylable form SUMO-1 tunes the p53 response by modifying p53 transcriptional program, by promoting binding onto selected promoters and by favoring apoptosis. By contrast, when non-acetylable, SUMO-1 enforces cell-cycle arrest and p53 binding to a different sets of genes. These data demonstrate for the first time that SUMO-1, a post-translational modification is, in turn, modified by acetylation. Further, they imply that the pleiotropy of effects by which SUMO-1 influences various cellular outcomes and the activity of p53 depends upon its acetylation state.
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Affiliation(s)
- Amrita Cheema
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia, USA
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Snow JW, Kim J, Currie CR, Xu J, Orkin SH. Sumoylation regulates interaction of FOG1 with C-terminal-binding protein (CTBP). J Biol Chem 2010; 285:28064-75. [PMID: 20587419 PMCID: PMC2934671 DOI: 10.1074/jbc.m109.096909] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2009] [Revised: 05/18/2010] [Indexed: 11/10/2022] Open
Abstract
Erythropoietic and megakaryocytic programs are specified from multipotential progenitors by the transcription factor GATA1. FOG1, a GATA1-interaction partner, is critical for GATA1 function in several contexts by bringing multiple complexes into association with GATA1 to facilitate activation or repression of target genes. To further elucidate regulation of these associations by cellular and extracellular cues, we examined FOG1 for post-translational modifications. We found that FOG1 is SUMOylated and phosphorylated in erythroid cells in a differentiation-dependent manner. Removal of the SUMOylation sites in FOG1 does not impair nuclear localization, protein stability, or chromatin occupancy. However, SUMOylation of FOG1 modulates interactions with C-terminal binding protein family members, specifically promoting CTBP1 binding. Phosphorylation of FOG1 modulates SUMOylation and, therefore, indirectly regulates the CTBP interaction. Post-translational modification of FOG1 may contribute to control of co-occupancy by CTBP family members, the NuRD complex, and GATA1 at differentially regulated genes.
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Affiliation(s)
- Jonathan W. Snow
- From the Division of Hematology/Oncology, Children's Hospital
- the Dana Farber Cancer Institute
- Harvard Medical School, and
| | - Jonghwan Kim
- From the Division of Hematology/Oncology, Children's Hospital
- the Dana Farber Cancer Institute
- Harvard Medical School, and
- the Howard Hughes Medical Institute, Boston, Massachusetts 02115
| | - Caroline R. Currie
- From the Division of Hematology/Oncology, Children's Hospital
- the Dana Farber Cancer Institute
| | - Jian Xu
- From the Division of Hematology/Oncology, Children's Hospital
- Harvard Medical School, and
- the Howard Hughes Medical Institute, Boston, Massachusetts 02115
| | - Stuart H. Orkin
- From the Division of Hematology/Oncology, Children's Hospital
- the Dana Farber Cancer Institute
- Harvard Medical School, and
- the Howard Hughes Medical Institute, Boston, Massachusetts 02115
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Bauer DC, Buske FA, Bailey TL, Bodén M. Predicting SUMOylation sites in developmental transcription factors of Drosophila melanogaster. Neurocomputing 2010. [DOI: 10.1016/j.neucom.2010.01.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Dual-functioning transcription factors in the developmental gene network of Drosophila melanogaster. BMC Bioinformatics 2010; 11:366. [PMID: 20594356 PMCID: PMC2912886 DOI: 10.1186/1471-2105-11-366] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Accepted: 07/02/2010] [Indexed: 01/10/2023] Open
Abstract
Background Quantitative models for transcriptional regulation have shown great promise for advancing our understanding of the biological mechanisms underlying gene regulation. However, all of the models to date assume a transcription factor (TF) to have either activating or repressing function towards all the genes it is regulating. Results In this paper we demonstrate, on the example of the developmental gene network in D. melanogaster, that the data-fit can be improved by up to 40% if the model is allowing certain TFs to have dual function, that is, acting as activator for some genes and as repressor for others. We demonstrate that the improvement is not due to additional flexibility in the model but rather derived from the data itself. We also found no evidence for the involvement of other known site-specific TFs in regulating this network. Finally, we propose SUMOylation as a candidate biological mechanism allowing TFs to switch their role when a small ubiquitin-like modifier (SUMO) is covalently attached to the TF. We strengthen this hypothesis by demonstrating that the TFs predicted to have dual function also contain the known SUMO consensus motif, while TFs predicted to have only one role lack this motif. Conclusions We argue that a SUMOylation-dependent mechanism allowing TFs to have dual function represents a promising area for further research and might be another step towards uncovering the biological mechanisms underlying transcriptional regulation.
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