1
|
Transcription Factor MAFB as a Prognostic Biomarker for the Lung Adenocarcinoma. Int J Mol Sci 2022; 23:ijms23179945. [PMID: 36077342 PMCID: PMC9456510 DOI: 10.3390/ijms23179945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/18/2022] [Accepted: 08/29/2022] [Indexed: 11/17/2022] Open
Abstract
MAFB is a basic leucine zipper (bZIP) transcription factor specifically expressed in macrophages. We have previously identified MAFB as a candidate marker for tumor-associated macrophages (TAMs) in human and mouse models. Here, we analyzed single-cell sequencing data of patients with lung adenocarcinoma obtained from the GEO database (GSE131907). Analyzed data showed that general macrophage marker CD68 and macrophage scavenger receptor 1 (CD204) were expressed in TAM and lung tissue macrophage clusters, while transcription factor MAFB was expressed specifically in TAM clusters. Clinical records of 120 patients with lung adenocarcinoma stage I (n = 57), II (n = 21), and III (n = 42) were retrieved from Tsukuba Human Tissue Biobank Center (THB) in the University of Tsukuba Hospital, Japan. Tumor tissues from these patients were extracted and stained with anti-human MAFB antibody, and then MAFB-positive cells relative to the tissue area (MAFB+ cells/tissue area) were morphometrically quantified. Our results indicated that higher numbers of MAFB+ cells significantly correlated to increased local lymph node metastasis (nodal involvement), high recurrence rate, poor pathological stage, increased lymphatic permeation, higher vascular invasion, and pleural infiltration. Moreover, increased amounts of MAFB+ cells were related to poor overall survival and disease-free survival, especially in smokers. These data indicate that MAFB may be a suitable prognostic biomarker for smoker lung cancer patients.
Collapse
|
2
|
Macrophage-Specific, Mafb-Deficient Mice Showed Delayed Skin Wound Healing. Int J Mol Sci 2022; 23:ijms23169346. [PMID: 36012611 PMCID: PMC9409077 DOI: 10.3390/ijms23169346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/12/2022] [Accepted: 08/15/2022] [Indexed: 11/20/2022] Open
Abstract
Macrophages play essential roles throughout the wound repair process. Nevertheless, mechanisms regulating the process are poorly understood. MAFB is specifically expressed in the macrophages in hematopoietic tissue and is vital to homeostatic function. Comparison of the skin wound repair rates in macrophage-specific, MAFB-deficient mice (Mafbf/f::LysM-Cre) and control mice (Mafbf/f) showed that wound healing was significantly delayed in the former. For wounded GFP knock-in mice with GFP inserts in the Mafb locus, flow cytometry revealed that their GFP-positive cells expressed macrophage markers. Thus, macrophages express Mafb at wound sites. Immunohistochemical (IHC) staining, proteome analysis, and RT-qPCR of the wound tissue showed relative downregulation of Arg1, Ccl12, and Ccl2 in Mafbf/f::LysM-Cre mice. The aforementioned genes were also downregulated in the bone marrow-derived, M2-type macrophages of Mafbf/f::LysM-Cre mice. Published single-cell RNA-Seq analyses showed that Arg1, Ccl2, Ccl12, and Il-10 were expressed in distinct populations of MAFB-expressing cells. Hence, the MAFB-expressing macrophage population is heterogeneous. MAFB plays the vital role of regulating multiple genes implicated in wound healing, which suggests that MAFB is a potential therapeutic target in wound healing.
Collapse
|
3
|
Hashimoto D, Colet JGR, Murashima A, Fujimoto K, Ueda Y, Suzuki K, Hyuga T, Hemmi H, Kaisho T, Takahashi S, Takahama Y, Yamada G. Radiation inducible MafB gene is required for thymic regeneration. Sci Rep 2021; 11:10439. [PMID: 34001954 PMCID: PMC8129107 DOI: 10.1038/s41598-021-89836-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 04/23/2021] [Indexed: 11/28/2022] Open
Abstract
The thymus facilitates mature T cell production by providing a suitable stromal microenvironment. This microenvironment is impaired by radiation and aging which lead to immune system disturbances known as thymic involution. Young adult thymus shows thymic recovery after such involution. Although various genes have been reported for thymocytes and thymic epithelial cells in such processes, the roles of stromal transcription factors in these remain incompletely understood. MafB (v-maf musculoaponeurotic fibrosarcoma oncogene homolog B) is a transcription factor expressed in thymic stroma and its expression was induced a day after radiation exposure. Hence, the roles of mesenchymal MafB in the process of thymic regeneration offers an intriguing research topic also for radiation biology. The current study investigated whether MafB plays roles in the adult thymus. MafB/green fluorescent protein knock-in mutant (MafB+/GFP) mice showed impaired thymic regeneration after the sublethal irradiation, judged by reduced thymus size, total thymocyte number and medullary complexity. Furthermore, IL4 was induced after irradiation and such induction was reduced in mutant mice. The mutants also displayed signs of accelerated age-related thymic involution. Altogether, these results suggest possible functions of MafB in the processes of thymic recovery after irradiation, and maintenance during aging.
Collapse
Affiliation(s)
- Daiki Hashimoto
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Jose Gabriel R Colet
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan.,Experimental Therapeutics Laboratory, University of South Australia Cancer Research Institute, Clinical and Health Sciences, University of South Australia, Adelaide, SA, Australia
| | - Aki Murashima
- Department of Anatomy, Iwate Medical University, Yahaba, Iwate, Japan.
| | - Kota Fujimoto
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Yuko Ueda
- Department of Urology, Wakayama Medical University, Wakayama, Japan
| | - Kentaro Suzuki
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Taiju Hyuga
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan
| | - Hiroaki Hemmi
- Laboratory of Immunology, Faculty of Veterinary Medicine, Okayama University of Science, Imabari, Ehime, Japan
| | - Tsuneyasu Kaisho
- Department of Immunology, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera, Wakayama, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tennodai, Japan
| | - Yousuke Takahama
- Experimental Immunology Branch, National Cancer Institute, NIH, Bethesda, MD, 20892, USA
| | - Gen Yamada
- Department of Developmental Genetics, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera 811-1, Wakayama City, Wakayama, 641-8509, Japan.
| |
Collapse
|
4
|
Takahashi S. Functional analysis of large MAF transcription factors and elucidation of their relationships with human diseases. Exp Anim 2021; 70:264-271. [PMID: 33762508 PMCID: PMC8390310 DOI: 10.1538/expanim.21-0027] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The large MAF transcription factor group is a group of transcription factors with an acidic region, a basic region, and a leucine zipper region. Four types of MAF, MAFA, MAFB, c-MAF, and NRL, have been identified in humans and mice. In order to elucidate the functions of the large MAF transcription factor group in vivo, our research group created genetically modified MAFA-, MAFB-, and c-MAF-deficient mice and analyzed their phenotypes. MAFA is expressed in pancreatic β cells and is essential for insulin transcription and secretion. MAFB is essential for the development of pancreatic endocrine cells, formation of inner ears, podocyte function in the kidneys, and functional differentiation of macrophages. c-MAF is essential for lens formation and osteoblast differentiation. Furthermore, a single-base mutation in genes encoding the large MAF transcription factor group causes congenital renal disease, eye disease, bone disease, diabetes, and tumors in humans. This review describes the functions of large MAF transcription factors in vivo and their relationships with human diseases.
Collapse
Affiliation(s)
- Satoru Takahashi
- Department of Anatomy and Embryology, Laboratory Animal Resource Center in Transborder Medical Research Center, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| |
Collapse
|
5
|
Li L, Bao J, Wang H, Lei JH, Peng C, Zeng J, Hao W, Zhang X, Xu X, Yu C, Deng CX, Chen Q. Upregulation of amplified in breast cancer 1 contributes to pancreatic ductal adenocarcinoma progression and vulnerability to blockage of hedgehog activation. Theranostics 2021; 11:1672-1689. [PMID: 33408774 PMCID: PMC7778610 DOI: 10.7150/thno.47390] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 10/19/2020] [Indexed: 12/13/2022] Open
Abstract
Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and devastating cancers without effective treatments. Amplified in breast cancer 1 (AIB1) is a member of the steroid receptor coactivator family that mediates the transcriptional activities of nuclear receptors. While AIB1 is associated with the initiation and progression of multiple cancers, the mechanism by which AIB1 contributes to PDAC progression remains unknown. In this study, we aimed to explore the role of AIB1 in the progression of PDAC and elucidate the underlying mechanisms. Methods: The clinical significance and mRNA level of AIB1 in PDAC were studied by database analysis. To demonstrate whether AIB1 mediates the malignant features of PDAC cells, namely, proliferation, migration, invasion, we performed real-time PCR and Western blot analysis, established xenograft models and used in vivo metastasis assay. With insights into the mechanism of AIB1, we performed RNA sequencing (Seq), ChIP-Seq, luciferase reporter assays and pull-down assays. Furthermore, we analyzed the relationship between AIB1 expression and its target expression in PDAC cells and patients and explored whether PDAC cells with high AIB1 levels are sensitive to inhibitors of its target. Results: We found that AIB1 was significantly upregulated in PDAC and associated with its malignancy. Silencing AIB1 impaired hedgehog (Hh) activation by reducing the expression of smoothened (SMO), leading to cell cycle arrest and the inhibition of PDAC cell proliferation. In addition, AIB1, via upregulation of integrin αv (ITGAV) expression, promoted extracellular matrix (ECM) signaling, which played an important role in PDAC progression. Further studies showed that AIB1 preferably bound to AP-1 related elements and served as a coactivator for enhancing the transcriptional activity of MafB, which promoted the expression of SMO and ITGAV. PDAC cells with high AIB1 levels were sensitive to Hh signaling inhibitors, suggesting that blocking Hh activation is an effective treatment against PDAC with high AIB1 expression. Conclusions: These findings reveal that AIB1 is a crucial oncogenic regulator associated with PDAC progression via Hh and ECM signaling and suggest potential therapeutic targets for PDAC treatment.
Collapse
Affiliation(s)
- Licen Li
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Jiaolin Bao
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Haitao Wang
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Josh Haipeng Lei
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Cheng Peng
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Jianming Zeng
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Wenhui Hao
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Xu Zhang
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Xiaoling Xu
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Chundong Yu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361012, China
| | - Chu-Xia Deng
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Qiang Chen
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Centre for Precision Medicine Research and Training, Faculty of Health Sciences, University of Macau, Macau SAR, China
- Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325000, China
| |
Collapse
|
6
|
Robertson H, Dinkova-Kostova AT, Hayes JD. NRF2 and the Ambiguous Consequences of Its Activation during Initiation and the Subsequent Stages of Tumourigenesis. Cancers (Basel) 2020; 12:E3609. [PMID: 33276631 PMCID: PMC7761610 DOI: 10.3390/cancers12123609] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/19/2020] [Accepted: 11/27/2020] [Indexed: 02/06/2023] Open
Abstract
NF-E2 p45-related factor 2 (NRF2, encoded in the human by NFE2L2) mediates short-term adaptation to thiol-reactive stressors. In normal cells, activation of NRF2 by a thiol-reactive stressor helps prevent, for a limited period of time, the initiation of cancer by chemical carcinogens through induction of genes encoding drug-metabolising enzymes. However, in many tumour types, NRF2 is permanently upregulated. In such cases, its overexpressed target genes support the promotion and progression of cancer by suppressing oxidative stress, because they constitutively increase the capacity to scavenge reactive oxygen species (ROS), and they support cell proliferation by increasing ribonucleotide synthesis, serine biosynthesis and autophagy. Herein, we describe cancer chemoprevention and the discovery of the essential role played by NRF2 in orchestrating protection against chemical carcinogenesis. We similarly describe the discoveries of somatic mutations in NFE2L2 and the gene encoding the principal NRF2 repressor, Kelch-like ECH-associated protein 1 (KEAP1) along with that encoding a component of the E3 ubiquitin-ligase complex Cullin 3 (CUL3), which result in permanent activation of NRF2, and the recognition that such mutations occur frequently in many types of cancer. Notably, mutations in NFE2L2, KEAP1 and CUL3 that cause persistent upregulation of NRF2 often co-exist with mutations that activate KRAS and the PI3K-PKB/Akt pathway, suggesting NRF2 supports growth of tumours in which KRAS or PKB/Akt are hyperactive. Besides somatic mutations, NRF2 activation in human tumours can occur by other means, such as alternative splicing that results in a NRF2 protein which lacks the KEAP1-binding domain or overexpression of other KEAP1-binding partners that compete with NRF2. Lastly, as NRF2 upregulation is associated with resistance to cancer chemotherapy and radiotherapy, we describe strategies that might be employed to suppress growth and overcome drug resistance in tumours with overactive NRF2.
Collapse
Affiliation(s)
- Holly Robertson
- Jacqui Wood Cancer Centre, Division of Cellular Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK; (H.R.); (A.T.D.-K.)
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Cambridge CB10 1SA, UK
| | - Albena T. Dinkova-Kostova
- Jacqui Wood Cancer Centre, Division of Cellular Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK; (H.R.); (A.T.D.-K.)
| | - John D. Hayes
- Jacqui Wood Cancer Centre, Division of Cellular Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK; (H.R.); (A.T.D.-K.)
| |
Collapse
|
7
|
Imbratta C, Hussein H, Andris F, Verdeil G. c-MAF, a Swiss Army Knife for Tolerance in Lymphocytes. Front Immunol 2020; 11:206. [PMID: 32117317 PMCID: PMC7033575 DOI: 10.3389/fimmu.2020.00206] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/27/2020] [Indexed: 12/11/2022] Open
Abstract
Beyond its well-admitted role in development and organogenesis, it is now clear that the transcription factor c-Maf has owned its place in the realm of immune-related transcription factors. Formerly introduced solely as a Th2 transcription factor, the role attributed to c-Maf has gradually broadened over the years and has extended to most, if not all, known immune cell types. The influence of c-Maf is particularly prominent among T cell subsets, where c-Maf regulates the differentiation as well as the function of multiple subsets of CD4 and CD8 T cells, lending it a crucial position in adaptive immunity and anti-tumoral responsiveness. Recent research has also revealed the role of c-Maf in controlling Th17 responses in the intestine, positioning it as an essential factor in intestinal homeostasis. This review aims to present and discuss the recent advances highlighting the particular role played by c-Maf in T lymphocyte differentiation, function, and homeostasis.
Collapse
Affiliation(s)
- Claire Imbratta
- Department of Oncology, University of Lausanne, Lausanne, Switzerland
| | - Hind Hussein
- Laboratoire d'Immunobiologie, Université Libre de Bruxelles, Brussels, Belgium
| | - Fabienne Andris
- Laboratoire d'Immunobiologie, Université Libre de Bruxelles, Brussels, Belgium
| | - Grégory Verdeil
- Department of Oncology, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
8
|
Abstract
The transcription factor MafB regulates macrophage differentiation. However, studies on
the phenotype of Mafb-deficient macrophages are still limited. Recently,
it was shown that the specific expression of MafB permits macrophages to be distinguished
from dendritic cells. In addition, MafB has been reported to be involved in various
diseases related to macrophages. Studies using macrophage-specific
Mafb-deficient mice show that MafB is linked to atherosclerosis,
autoimmunity, obesity, and ischemic stroke, all of which exhibit macrophage abnormality.
Therefore, MafB is hypothesized to be indispensable for the regulation of macrophages to
maintain systemic homeostasis and may serve as an innovative target for treating
macrophage-related diseases.
Collapse
Affiliation(s)
- Michito Hamada
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Laboratory Animal Resource Center (LARC), Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Yuki Tsunakawa
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Ph.D. Program in Human Biology, School of Integrative and Global Majors, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Hyojung Jeon
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Laboratory Animal Resource Center (LARC), Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Manoj Kumar Yadav
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Ph.D. Program in Human Biology, School of Integrative and Global Majors, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Laboratory Animal Resource Center (LARC), Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| |
Collapse
|
9
|
He M, Wang J, Yin Z, Zhao Y, Hou H, Fan J, Li H, Wen Z, Tang J, Wang Y, Wang DW, Chen C. MiR-320a induces diabetic nephropathy via inhibiting MafB. Aging (Albany NY) 2019; 11:3055-3079. [PMID: 31102503 PMCID: PMC6555468 DOI: 10.18632/aging.101962] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 05/06/2019] [Indexed: 12/17/2022]
Abstract
Multiple studies indicate that microRNAs (miRNAs) are involved in diabetes. However, the roles of miRNA in the target organ damages in diabetes remain unclear. This study investigated the functions of miR-320a in diabetic nephropathy (DN). In this study, db/db mice were used to observe the changes in podocytes and their function in vivo, as well as in cultured mouse podocyte cells (MPC5) exposed to high glucose in vitro. To further explore the role of miR-320a in DN, recombinant adeno-associated viral particle was administered intravenously to manipulate the expression of miR-320a in db/db mice. Overexpression of miR-320a markedly promoted podocyte loss and dysfunction in DN, including mesangial expansion and increased levels of proteinuria, serum creatinine and urea nitrogen. Furthermore, MafB was identified as a direct target of miR-320a through AGO2 co-immunoprecipitation, luciferase reporter assay, and Western blotting. Moreover, re-expression of MafB rescued miR-320a-induced podocyte loss and dysfunction by upregulating the expressions of Nephrin and glutathione peroxidase 3 (Gpx3). Our data indicated that miR-320a aggravated renal disfunction in DN by targeting MafB and downregulating Nephrin and Gpx3 in podocytes, which suggested that miR-320a could be a potential therapeutic target of diabetic nephropathy.
Collapse
Affiliation(s)
- Mengying He
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jin Wang
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zhongwei Yin
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yanru Zhao
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Huiying Hou
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jiahui Fan
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Huaping Li
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zheng Wen
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jiarong Tang
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yan Wang
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Dao Wen Wang
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Chen Chen
- Division of Cardiology and Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| |
Collapse
|
10
|
Han X, Shao W, Yue Z, Xing L, Shen L, Long C, Zhang D, He D, Lin T, Wei G. [Di (2-ethylhexyl) phthalate-induced hypospadias in SD rats is related with Mafb expression: a transcriptome profiling-based study]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2019; 39:456-463. [PMID: 31068290 DOI: 10.12122/j.issn.1673-4254.2019.04.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To investigate the transcriptome profile of genital tubercles (GTs) in male SD rats and explore the mechanism of hypospadias induced by Di (2-ethylhexyl) phthalate (DEHP). METHODS Forty time-pregnant SD rats were randomly divided into 4 equal groups, namely GD16 group and GD19 group (in which the male GTs were collected on gestation day[GD]16 and GD19 for RNA-seq, respectively), control group and DEHP exposure group (with administration of oil and 750 mg/kg DEHP by gavage from GD12 to GD19, respectively).In the control and DEHP exposure groups, the GTs were collected from the male fetuses on GD19.5, and scanning electron microscopy and HE staining were used to observe the morphological changes.The differentially expressed genes (DEGs) in the GTs were screened using lllumina HiSeq 2000 followed by GO and KEGG enrichment analyses to characterize the transcriptome profile.Immunofluorescence assay was performed to verify the DEGs (Mafb) identified by RNA-seq results.Immunofluorescence assay and Western blotting were used to examine the expression levels of Mafb in the penile tissue. RESULTS A total of 1360 DEGs were detected in the GTs between GD16 group and GD19 group by RNA-seq.Among these genes, 797 were up-regulated and 563 were down-regulated.These DEGs were mainly enriched in the cell adhesion plaque signaling pathway, axon guidance signaling pathway, and extracellular matrix receptor signaling pathway.Compared with that in GD16 group, Mafb was significantly up-regulated in GD19 group, which was consistent with the sequencing results.Mafb and β-catenin were significantly down-regulated in DEHP-exposed group compared with the control group (P < 0.01). CONCLUSIONS Mafb expression increases progressively with the development of GTs in male SD rats.DEHP exposure causes significant down-regulation of Mafb and β-catenin, suggesting that β-catenin signaling pathway that affects Mafb is related to DEHP-induced hypospadias in SD rats.
Collapse
Affiliation(s)
- Xiang Han
- Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing 400014, China
| | - Wang Shao
- Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing 400014, China
| | - Zhou Yue
- Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing 400014, China
| | - Liu Xing
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Lianju Shen
- Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing 400014, China
| | - Chunlan Long
- Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing 400014, China
| | - Deying Zhang
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Dawei He
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Tao Lin
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Guanghui Wei
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing 400014, China
| |
Collapse
|
11
|
Qiang YW, Ye S, Huang Y, Chen Y, Van Rhee F, Epstein J, Walker BA, Morgan GJ, Davies FE. MAFb protein confers intrinsic resistance to proteasome inhibitors in multiple myeloma. BMC Cancer 2018; 18:724. [PMID: 29980194 PMCID: PMC6035431 DOI: 10.1186/s12885-018-4602-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 06/18/2018] [Indexed: 11/29/2022] Open
Abstract
Background Multiple myeloma (MM) patients with t(14;20) have a poor prognosis and their outcome has not improved following the introduction of bortezomib (Bzb). The mechanism underlying the resistance to proteasome inhibitors (PIs) for this subset of patients is unknown. Methods IC50 of Bzb and carfilzomib (CFZ) in human myeloma cell lines (HMCLs) were established by MTT assay. Gene Expression profile (GEP) analysis was used to determine gene expression in primary myeloma cells. Immunoblotting analysis was performed for MAFb and caspase family proteins. Immunofluorescence staining was used to detect the location of MAFb protein in MM cells. Lentiviral infections were used to knock-down MAFb expression in two lines. Apoptosis detection by flow cytometry and western blot analysis was performed to determine the molecular mechanism MAFb confers resistance to proteasome inhibitors. Results We found high levels of MAFb protein in cell lines with t(14;20), in one line with t(6;20), in one with Igλ insertion into MAFb locus, and in primary plasma cells from MM patients with t(14;20). High MAFb protein levels correlated with higher IC50s of PIs in MM cells. Inhibition of GSK3β activity or treatment with Bzb or CFZ prevented MAFb protein degradation without affecting the corresponding mRNA level indicating a role for GSK3 and proteasome inhibitors in regulation of MAFb stability. Silencing MAFb restored sensitivity to Bzb and CFZ, and enhanced PIs-induced apoptosis and activation of caspase-3, − 8, − 9, PARP and lamin A/C suggesting that high expression of MAFb protein leads to insensitivity to proteasome inhibitors. Conclusion These results highlight the role of post-translational modification of MAFb in maintaining its protein level, and identify a mechanism by which proteasome inhibitors induced stabilization of MAFb confers resistance to proteasome inhibitors, and provide a rationale for the development of targeted therapeutic strategies for this subset of patients. Electronic supplementary material The online version of this article (10.1186/s12885-018-4602-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Ya-Wei Qiang
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA.
| | - Shiqiao Ye
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| | - Yuhua Huang
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| | - Yu Chen
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| | - Frits Van Rhee
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| | - Joshua Epstein
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| | - Brian A Walker
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| | - Gareth J Morgan
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| | - Faith E Davies
- Myeloma Institute, University of Arkansas for Medical Sciences, Winthrop P. Rockefeller Cancer Institute, 4301 West Markham St., Slot 776, Rm 914, Little Rock, AR, 72205, USA
| |
Collapse
|
12
|
Pajcini KV, Xu L, Shao L, Petrovic J, Palasiewicz K, Ohtani Y, Bailis W, Lee C, Wertheim GB, Mani R, Muthusamy N, Li Y, Meijerink JPP, Blacklow SC, Faryabi RB, Cherry S, Pear WS. MAFB enhances oncogenic Notch signaling in T cell acute lymphoblastic leukemia. Sci Signal 2017; 10:10/505/eaam6846. [PMID: 29138297 DOI: 10.1126/scisignal.aam6846] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Activating mutations in the gene encoding the cell-cell contact signaling protein Notch1 are common in human T cell acute lymphoblastic leukemias (T-ALLs). However, expressing Notch1 mutant alleles in mice fails to efficiently induce the development of leukemia. We performed a gain-of-function screen to identify proteins that enhanced signaling by leukemia-associated Notch1 mutants. The transcription factors MAFB and ETS2 emerged as candidates that individually enhanced Notch1 signaling, and when coexpressed, they synergistically increased signaling to an extent similar to that induced by core components of the Notch transcriptional complex. In mouse models of T-ALL, MAFB enhanced leukemogenesis by the naturally occurring Notch1 mutants, decreased disease latency, and increased disease penetrance. Decreasing MAFB abundance in mouse and human T-ALL cells reduced the expression of Notch1 target genes, including MYC and HES1, and sustained MAFB knockdown impaired T-ALL growth in a competitive setting. MAFB bound to ETS2 and interacted with the acetyltransferases PCAF and P300, highlighting its importance in recruiting coactivators that enhance Notch1 signaling. Together, these data identify a mechanism for enhancing the oncogenic potential of weak Notch1 mutants in leukemia models, and they reveal the MAFB-ETS2 transcriptional axis as a potential therapeutic target in T-ALL.
Collapse
Affiliation(s)
- Kostandin V Pajcini
- Department of Pharmacology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA. .,Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lanwei Xu
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lijian Shao
- Department of Pharmacology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Jelena Petrovic
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karol Palasiewicz
- Department of Pharmacology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Yumi Ohtani
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Will Bailis
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Curtis Lee
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Gerald B Wertheim
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rajeswaran Mani
- The James, Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA
| | - Natarajan Muthusamy
- The James, Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA
| | - Yunlei Li
- Department of Pediatric Oncology/Hematology, Erasmus Medical Center, Rotterdam, Netherlands
| | | | - Stephen C Blacklow
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Robert B Faryabi
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sara Cherry
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Warren S Pear
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA. .,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
13
|
Nakatani T, Partridge NC. MEF2C Interacts With c-FOS in PTH-Stimulated Mmp13 Gene Expression in Osteoblastic Cells. Endocrinology 2017; 158:3778-3791. [PMID: 28973134 PMCID: PMC5695834 DOI: 10.1210/en.2017-00159] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/18/2017] [Indexed: 01/01/2023]
Abstract
Parathyroid hormone (PTH) regulates the transcription of many genes in the osteoblast. One of these genes is Mmp13, which is involved in bone remodeling and early stages of endochondral bone formation. Previously, we reported that PTH induces Mmp13 transcription by regulating the dissociation of histone deacetylase 4 (HDAC4) from runt-related transcription factor 2 (Runx2), and the association of the HATs, p300, and p300/CREB binding protein (CBP)-associated factor. It is known that, in addition to Runx2, HDAC4 binds to the transcription factor, myocyte-specific enhancer factor 2c (MEF2C), and represses its activity. In this work, we investigated whether MEF2C participates in PTH-stimulated Mmp13 gene expression in osteoblastic cells and how it does so. Knockdown of Mef2c in UMR 106-01 cells repressed Mmp13 messenger RNA expression and promoter activity with or without PTH treatment. Chromatin immunoprecipitation (ChIP) assays showed that MEF2C associated with the Mmp13 promoter; this increased after 4 hours of PTH treatment. ChIP-reChIP results indicate that endogenous MEF2C associates with HDAC4 on the Mmp13 promoter; after PTH treatment, this association decreased. From gel shift, ChIP, and promoter-reporter assays, MEF2C was found to associate with the activator protein-1 (AP-1) site without directly binding to DNA and had its stimulatory effect through interaction with c-FOS. In conclusion, MEF2C is necessary for Mmp13 gene expression at the transcriptional level and participates in PTH-stimulated Mmp13 gene expression by increased binding to c-FOS at the AP-1 site in the Mmp13 promoter. The observation of MEF2C interacting with a member of the AP-1 transcription factor family provides knowledge of the functions of HDAC4, c-FOS, and MEF2C.
Collapse
Affiliation(s)
- Teruyo Nakatani
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, New York 10010
| | - Nicola C. Partridge
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, New York 10010
| |
Collapse
|
14
|
A Comprehensive Survey of the Roles of Highly Disordered Proteins in Type 2 Diabetes. Int J Mol Sci 2017; 18:ijms18102010. [PMID: 28934129 PMCID: PMC5666700 DOI: 10.3390/ijms18102010] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 09/04/2017] [Accepted: 09/12/2017] [Indexed: 01/03/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a chronic and progressive disease that is strongly associated with hyperglycemia (high blood sugar) related to either insulin resistance or insufficient insulin production. Among the various molecular events and players implicated in the manifestation and development of diabetes mellitus, proteins play several important roles. The Kyoto Encyclopedia of Genes and Genomes (KEGG) database has information on 34 human proteins experimentally shown to be related to the T2DM pathogenesis. It is known that many proteins associated with different human maladies are intrinsically disordered as a whole, or contain intrinsically disordered regions. The presented study shows that T2DM is not an exception to this rule, and many proteins known to be associated with pathogenesis of this malady are intrinsically disordered. The multiparametric bioinformatics analysis utilizing several computational tools for the intrinsic disorder characterization revealed that IRS1, IRS2, IRS4, MAFA, PDX1, ADIPO, PIK3R2, PIK3R5, SoCS1, and SoCS3 are expected to be highly disordered, whereas VDCC, SoCS2, SoCS4, JNK9, PRKCZ, PRKCE, insulin, GCK, JNK8, JNK10, PYK, INSR, TNF-α, MAPK3, and Kir6.2 are classified as moderately disordered proteins, and GLUT2, GLUT4, mTOR, SUR1, MAPK1, IKKA, PRKCD, PIK3CB, and PIK3CA are predicted as mostly ordered. More focused computational analyses and intensive literature mining were conducted for a set of highly disordered proteins related to T2DM. The resulting work represents a comprehensive survey describing the major biological functions of these proteins and functional roles of their intrinsically disordered regions, which are frequently engaged in protein–protein interactions, and contain sites of various posttranslational modifications (PTMs). It is also shown that intrinsic disorder-associated PTMs may play important roles in controlling the functions of these proteins. Consideration of the T2DM proteins from the perspective of intrinsic disorder provides useful information that can potentially lead to future experimental studies that may uncover latent and novel pathways associated with the disease.
Collapse
|
15
|
Nemoto T, Shibata Y, Inoue S, Igarashi A, Tokairin Y, Yamauchi K, Kimura T, Sato M, Sato K, Nakano H, Abe S, Nishiwaki M, Kobayashi M, Yang S, Minegishi Y, Furuyama K, Machida H, Kubota I. MafB silencing in macrophages does not influence the initiation and growth of lung cancer induced by urethane. EXCLI JOURNAL 2017; 16:914-920. [PMID: 28900373 PMCID: PMC5579402 DOI: 10.17179/excli2017-325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/22/2017] [Indexed: 12/26/2022]
Abstract
An increased number of tumor-associated macrophages (TAMs) that exhibit the M2 macrophage phenotype is related to poorer prognosis in cancer patients. MafB is a transcription factor regulating the differentiation of macrophages. However, involvement of MafB for the development of TAMs is unknown. This study was designed to investigate the role of MafB in a murine urethane-induced lung cancer model. Urethane was injected intraperitoneally into wild-type and dominant-negative MafB transgenic mice. Twenty-four weeks later, mice were sacrificed and their lungs removed for pathological analysis. The numbers and mean areas of lung cancer were evaluated. In addition, the numbers of Mac-3-positive macrophages were evaluated in each tumor. The numbers and mean areas of lung cancer induced by urethane administration were not significantly different between wild-type and dominant-negative MafB transgenic mice. The numbers of TAMs in lung cancer tissue were not significantly different between the two groups. MafB silencing using dominant-negative MafB did not influence the initiation and growth of lung cancer in mice exposed to urethane. These data suggest that MafB may not be related to the development of TAMs.
Collapse
Affiliation(s)
- Takako Nemoto
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Yoko Shibata
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Sumito Inoue
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Akira Igarashi
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Yoshikane Tokairin
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Keiko Yamauchi
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Tomomi Kimura
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Masamichi Sato
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Kento Sato
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Hiroshi Nakano
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Shuichi Abe
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Michiko Nishiwaki
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Maki Kobayashi
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Sujeong Yang
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Yukihiro Minegishi
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Kodai Furuyama
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Hiroyoshi Machida
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| | - Isao Kubota
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan
| |
Collapse
|
16
|
Park JG, Tischfield MA, Nugent AA, Cheng L, Di Gioia SA, Chan WM, Maconachie G, Bosley TM, Summers CG, Hunter DG, Robson CD, Gottlob I, Engle EC. Loss of MAFB Function in Humans and Mice Causes Duane Syndrome, Aberrant Extraocular Muscle Innervation, and Inner-Ear Defects. Am J Hum Genet 2016; 98:1220-1227. [PMID: 27181683 DOI: 10.1016/j.ajhg.2016.03.023] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 03/21/2016] [Indexed: 11/16/2022] Open
Abstract
Duane retraction syndrome (DRS) is a congenital eye-movement disorder defined by limited outward gaze and retraction of the eye on attempted inward gaze. Here, we report on three heterozygous loss-of-function MAFB mutations causing DRS and a dominant-negative MAFB mutation causing DRS and deafness. Using genotype-phenotype correlations in humans and Mafb-knockout mice, we propose a threshold model for variable loss of MAFB function. Postmortem studies of DRS have reported abducens nerve hypoplasia and aberrant innervation of the lateral rectus muscle by the oculomotor nerve. Our studies in mice now confirm this human DRS pathology. Moreover, we demonstrate that selectively disrupting abducens nerve development is sufficient to cause secondary innervation of the lateral rectus muscle by aberrant oculomotor nerve branches, which form at developmental decision regions close to target extraocular muscles. Thus, we present evidence that the primary cause of DRS is failure of the abducens nerve to fully innervate the lateral rectus muscle in early development.
Collapse
Affiliation(s)
- Jong G Park
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, Boston, MA 02115, USA; Duke University School of Medicine, Durham, NC 27710, USA
| | - Max A Tischfield
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - Alicia A Nugent
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA
| | - Long Cheng
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Silvio Alessandro Di Gioia
- Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA
| | - Wai-Man Chan
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Gail Maconachie
- Ulverscroft Eye Unit, University of Leicester, Leicester LE2 7LX, UK; Department of Neuroscience, Psychology, and Behavior, University of Leicester, Leicester LE2 7LX, UK
| | - Thomas M Bosley
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD 21287, USA
| | - C Gail Summers
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA; Department of Pediatrics, University of Minnesota, Minneapolis, MN 55455, USA
| | - David G Hunter
- Department of Ophthalmology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Ophthalmology, Harvard Medical School, Boston, MA 02115, USA
| | - Caroline D Robson
- Department of Radiology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Radiology, Harvard Medical School, Boston, MA 02115, USA
| | - Irene Gottlob
- Ulverscroft Eye Unit, University of Leicester, Leicester LE2 7LX, UK; Department of Neuroscience, Psychology, and Behavior, University of Leicester, Leicester LE2 7LX, UK
| | - Elizabeth C Engle
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA; Department of Ophthalmology, Boston Children's Hospital, Boston, MA 02115, USA; Department of Ophthalmology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
| |
Collapse
|
17
|
Yang Y, Cvekl A. Large Maf Transcription Factors: Cousins of AP-1 Proteins and Important Regulators of Cellular Differentiation. ACTA ACUST UNITED AC 2016; 23:2-11. [PMID: 18159220 DOI: 10.23861/ejbm20072347] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A large number of mammalian transcription factors possess the evolutionary conserved basic and leucine zipper domain (bZIP). The basic domain interacts with DNA while the leucine zipper facilitates homo- and hetero-dimerization. These factors can be grouped into at least seven families: AP-1, ATF/CREB, CNC, C/EBP, Maf, PAR, and virus-encoded bZIPs. Here, we focus on a group of four large Maf proteins: MafA, MafB, c-Maf, and NRL. They act as key regulators of terminal differentiation in many tissues such as bone, brain, kidney, lens, pancreas, and retina, as well as in blood. The DNA-binding mechanism of large Mafs involves cooperation between the basic domain and an adjacent ancillary DNA-binding domain. Many genes regulated by Mafs during cellular differentiation use functional interactions between the Pax/Maf, Sox/Maf, and Ets/Maf promoter and enhancer modules. The prime examples are crystallin genes in lens and glucagon and insulin in pancreas. Novel roles for large Mafs emerged from studying generations of MafA and MafB knockouts and analysis of combined phenotypes in double or triple null mice. In addition, studies of this group of factors in invertebrates revealed the evolutionarily conserved function of these genes in the development of multicellular organisms.
Collapse
Affiliation(s)
- Ying Yang
- Departments of Ophthalmology and Visual Sciences and Molecular Genetics, Albert Einstein College of Medicine, Bronx, New York 10461
| | | |
Collapse
|
18
|
Zhang C, Guo Z. Multiple functions of Maf in the regulation of cellular development and differentiation. Diabetes Metab Res Rev 2015; 31:773-8. [PMID: 26122665 PMCID: PMC5042042 DOI: 10.1002/dmrr.2676] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 05/29/2015] [Accepted: 06/24/2015] [Indexed: 11/08/2022]
Abstract
Cellular muscular aponeurotic fibrosarcoma (c-Maf) is a member of the large macrophage-activating factor family. C-Maf plays important roles in the morphogenetic processes and cellular differentiation of the lens, kidneys, liver, T cells and nervous system, and it is particularly important in pancreatic islet and erythroblastic island formation. However, the exact role of c-Maf remains to be elucidated. In this review, we summarize the research to clarify the functions of c-Maf in the cellular development and differentiation. The expression of c-Maf is higher in pancreatic duct cells than in pancreatic islet cells. Therefore, we suggest that pancreatic duct cells may be converted to the functional insulin-secreting cells by regulating c-Maf.
Collapse
Affiliation(s)
- Chuan Zhang
- Department of Endocrinology and MetabolismThe Second Hospital of Jilin UniversityChangchunChina
| | - Zhi‐Min Guo
- Department of Experimental MicrobiologyThe First Hospital of Jilin UniversityChangchunChina
| |
Collapse
|
19
|
Pettersson AML, Acosta JR, Björk C, Krätzel J, Stenson B, Blomqvist L, Viguerie N, Langin D, Arner P, Laurencikiene J. MAFB as a novel regulator of human adipose tissue inflammation. Diabetologia 2015; 58:2115-23. [PMID: 26115698 DOI: 10.1007/s00125-015-3673-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 06/04/2015] [Indexed: 01/08/2023]
Abstract
AIMS/HYPOTHESIS Dysregulated expression of metabolic and inflammatory genes is a prominent consequence of obesity causing insulin resistance and type 2 diabetes. Finding causative factors is essential to understanding progression of these pathologies and discovering new therapeutic targets. The transcription factor V-maf musculoaponeurotic fibrosarcoma oncogene homologue B (MAFB) is highly expressed in human white adipose tissue (WAT). However, its role in the regulation of WAT function is elusive. We aimed to characterise MAFB expression and function in human WAT in the context of obesity and insulin resistance. METHODS MAFB mRNA expression was evaluated in human WAT from seven cohorts with large inter-individual variation in BMI and metabolic features. Insulin-induced adipocyte lipogenesis and lipolysis were measured and correlated with MAFB expression. MAFB regulation during adipogenesis and the effects of MAFB suppression in human adipocytes was investigated. MAFB regulation by TNF-α was examined in human primary adipocytes and THP-1 monocytes/macrophages. RESULTS MAFB expression in human adipocytes is upregulated during adipogenesis, increases with BMI in WAT, correlates with adverse metabolic features and is decreased after weight loss. MAFB downregulation decreases proinflammatory gene expression in adipocytes and interferes with TNF-α effects. Interestingly, MAFB is differentially regulated by TNF-α in adipocytes (suppressed) and THP-1 cells (upregulated). Further, MAFB is primarily expressed in WAT macrophages/monocytes and its expression correlates with macrophage and inflammatory markers. CONCLUSIONS/INTERPRETATION Our findings indicate that MAFB is a regulator and a marker of adipose tissue inflammation, a process that subsequently causes insulin resistance.
Collapse
Affiliation(s)
- Annie M L Pettersson
- Department of Medicine Huddinge, Lipid laboratory, Karolinska Institutet, Novum, NVS D4, Hälsovägen 7, 14186, Stockholm, Sweden
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Moon EJ, Giaccia A. Dual roles of NRF2 in tumor prevention and progression: possible implications in cancer treatment. Free Radic Biol Med 2015; 79:292-9. [PMID: 25458917 PMCID: PMC4339613 DOI: 10.1016/j.freeradbiomed.2014.11.009] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 11/13/2014] [Accepted: 11/13/2014] [Indexed: 12/16/2022]
Abstract
The cap'n'collar (CNC) family serves as cellular sensors of oxidative and electrophilic stresses and shares structural similarities including basic leucine zipper (bZIP) and CNC domains. They form heterodimers with small MAF proteins to regulate antioxidant and phase II enzymes through antioxidant response element (ARE)-mediated transactivation. Among the CNC family members, NRF2 is required for systemic protection against redox-mediated injury and carcinogenesis. On the other hand, NRF2 is activated by oncogenic pathways, metabolism, and hypoxia. Constitutive NRF2 activation is observed in a variety of human cancers and it is highly correlated with tumor progression and aggressiveness. In this review, we will discuss how NRF2 plays dual roles in cancer prevention and progression depending on the cellular context and environment. Therefore, a better understanding of NRF2 will be necessary to exploit this complex network of balancing antioxidant pathways to inhibit tumor progression.
Collapse
Affiliation(s)
- Eui Jung Moon
- Division of Radiation Biology & Oncology, Department of Radiation Oncology, Stanford University, Stanford, CA 94305, USA
| | - Amato Giaccia
- Division of Radiation Biology & Oncology, Department of Radiation Oncology, Stanford University, Stanford, CA 94305, USA.
| |
Collapse
|
21
|
Sexually dimorphic expression of Mafb regulates masculinization of the embryonic urethral formation. Proc Natl Acad Sci U S A 2014; 111:16407-12. [PMID: 25362053 DOI: 10.1073/pnas.1413273111] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Masculinization of external genitalia is an essential process in the formation of the male reproductive system. Prominent characteristics of this masculinization are the organ size and the sexual differentiation of the urethra. Although androgen is a pivotal inducer of the masculinization, the regulatory mechanism under the control of androgen is still unknown. Here, we address this longstanding question about how androgen induces masculinization of the embryonic external genitalia through the identification of the v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog B (Mafb) gene. Mafb is expressed prominently in the mesenchyme of male genital tubercle (GT), the anlage of external genitalia. MAFB expression is rarely detected in the mesenchyme of female GTs. However, exposure to exogenous androgen induces its mesenchymal expression in female GTs. Furthermore, MAFB expression is prominently down-regulated in male GTs of androgen receptor (Ar) KO mice, indicating that AR signaling is necessary for its expression. It is revealed that Mafb KO male GTs exhibit defective embryonic urethral formation, giving insight into the common human congenital anomaly hypospadias. However, the size of Mafb KO male GTs is similar with that of wild-type males. Moreover, androgen treatment fails to induce urethral masculinization of the GTs in Mafb KO mice. The current results provide evidence that Mafb is an androgen-inducible, sexually dimorphic regulator of embryonic urethral masculinization.
Collapse
|
22
|
Aida Y, Shibata Y, Abe S, Inoue S, Kimura T, Igarashi A, Yamauchi K, Nunomiya K, Kishi H, Nemoto T, Sato M, Sato-Nishiwaki M, Nakano H, Sato K, Kubota I. Inhibition of elastase-pulmonary emphysema in dominant-negative MafB transgenic mice. Int J Biol Sci 2014; 10:882-94. [PMID: 25170302 PMCID: PMC4147222 DOI: 10.7150/ijbs.8737] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 07/30/2014] [Indexed: 11/06/2022] Open
Abstract
Alveolar macrophages (AMs) play important roles in the pathogenesis of chronic obstructive pulmonary disease (COPD). We previously demonstrated upregulation of the transcription factor MafB in AMs of mice exposed to cigarette smoke. The aim of this study was to elucidate the roles of MafB in the development of pulmonary emphysema. Porcine pancreatic elastase was administered to wild-type (WT) and dominant-negative (DN)-MafB transgenic (Tg) mice in which MafB activity was suppressed only in macrophages. We measured the mean linear intercept and conducted cell differential analysis of bronchoalveolar lavage (BAL) cells, surface marker analysis using flow cytometry, and immunohistochemical staining using antibodies to matrix metalloproteinase (MMP)-9 and MMP-12. Airspace enlargement of the lungs was suppressed significantly in elastase-treated DN-MafB Tg mice compared with treated WT mice. AMs with projected pseudopods were decreased in DN-MafB Tg mice. The number of cells intermediately positive for F4/80 and weakly or intermediately positive for CD11b, which are considered cell subsets of matured AMs, decreased in the BAL of DN-MafB Tg mice. Furthermore, MMP-9 and -12 were significantly downregulated in BAL cells of DN-MafB Tg mice. Because MMPs exacerbate emphysema, MafB may be involved in pulmonary emphysema development through altered maturation of macrophages and MMP expression.
Collapse
Affiliation(s)
- Yasuko Aida
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Yoko Shibata
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Shuichi Abe
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Sumito Inoue
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Tomomi Kimura
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Akira Igarashi
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Keiko Yamauchi
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Keiko Nunomiya
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Hiroyuki Kishi
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Takako Nemoto
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Masamichi Sato
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Michiko Sato-Nishiwaki
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Hiroshi Nakano
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Kento Sato
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| | - Isao Kubota
- Department of Cardiology, Pulmonology, and Nephrology, School of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan
| |
Collapse
|
23
|
Morito N, Yoh K, Ojima M, Okamura M, Nakamura M, Hamada M, Shimohata H, Moriguchi T, Yamagata K, Takahashi S. Overexpression of Mafb in podocytes protects against diabetic nephropathy. J Am Soc Nephrol 2014; 25:2546-57. [PMID: 24722438 DOI: 10.1681/asn.2013090993] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
We previously showed that the transcription factor Mafb is essential for podocyte differentiation and foot process formation. Podocytes are susceptible to injury in diabetes, and this injury leads to progression of diabetic nephropathy. In this study, we generated transgenic mice that overexpress Mafb in podocytes using the nephrin promoter/enhancer. To examine a potential pathogenetic role for Mafb in diabetic nephropathy, Mafb transgenic mice were treated with either streptozotocin or saline solution. Diabetic nephropathy was assessed by renal histology and biochemical analyses of urine and serum. Podocyte-specific overexpression of Mafb had no effect on body weight or blood glucose levels in either diabetic or control mice. Notably, albuminuria and changes in BUN levels and renal histology observed in diabetic wild-type animals were ameliorated in diabetic Mafb transgenic mice. Moreover, hyperglycemia-induced downregulation of Nephrin was mitigated in diabetic Mafb transgenic mice, and reporter assay results suggested that Mafb regulates Nephrin directly. Mafb transgenic glomeruli also overexpressed glutathione peroxidase, an antioxidative stress enzyme, and levels of the oxidative stress marker 8-hydroxydeoxyguanosine decreased in the urine of diabetic Mafb transgenic mice. Finally, Notch2 expression increased in diabetic glomeruli, and this effect was enhanced in diabetic Mafb transgenic glomeruli. These data indicate Mafb has a protective role in diabetic nephropathy through regulation of slit diaphragm proteins, antioxidative enzymes, and Notch pathways in podocytes and suggest that Mafb could be a therapeutic target.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Homare Shimohata
- Department of Nephrology, Tokyo Medical University Ibaraki Medical Center, Inashiki, Ibaraki, Japan; and
| | - Takashi Moriguchi
- Department of Medical Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | | | - Satoru Takahashi
- Anatomy and Embryology, Faculty of Medicine, International Institute for Integrative Sleep Medicine (WPI-IIIS), and Life Science Center of Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Ibaraki, Japan
| |
Collapse
|
24
|
Sato-Nishiwaki M, Aida Y, Abe S, Shibata Y, Kimura T, Yamauchi K, Kishi H, Igarashi A, Inoue S, Sato M, Nakajima O, Kubota I. Reduced number and morphofunctional change of alveolar macrophages in MafB gene-targeted mice. PLoS One 2013; 8:e73963. [PMID: 24040127 PMCID: PMC3765310 DOI: 10.1371/journal.pone.0073963] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 07/25/2013] [Indexed: 01/19/2023] Open
Abstract
Alveolar macrophages (AMs) play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). We previously demonstrated that the transcription factor, MafB, increased in the AMs of mice exposed to cigarette smoke, and in those of human patients with COPD. The aim of this study was to evaluate the role of MafB in AMs using newly established transgenic (TG) mice that specifically express dominant negative (DN) MafB in macrophages under the control of macrophage scavenger receptor (MSR) enhancer-promoter. We performed cell differential analyses in bronchoalveolar lavage cells, morphological analyses with electron microscopy, and flow cytometry-based analyses of surface markers and a phagocytic capacity assay in macrophages. AM number in the TG mice was significantly decreased compared with wild-type (WT) mice. Morphologically, the high electron density area in the nucleus increased, the shape of pseudopods on the AMs was altered, and actin filament was less localized in the pseudopods of AMs of TG mice, compared with WT mice. The expression of surface markers, F4/80 and CD11b, on peritoneal macrophages in TG mice was reduced compared with WT mice, while those on AMs remained unchanged. Phagocytic capacity was decreased in AMs from TG mice, compared with WT mice. In conclusion, MafB regulates the phenotype of macrophages with respect to the number of alveolar macrophages, the nuclear compartment, cellular shape, surface marker expression, and phagocytic function. MSR-DN MafB TG mice may present a useful model to clarify the precise role of MafB in macrophages.
Collapse
MESH Headings
- Animals
- Antigens, Surface/metabolism
- Apoptosis
- Bronchoalveolar Lavage Fluid/cytology
- Gene Expression Regulation
- Genes, Dominant
- Humans
- Immunophenotyping
- Macrophages, Alveolar/immunology
- Macrophages, Alveolar/metabolism
- Macrophages, Alveolar/ultrastructure
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/metabolism
- MafB Transcription Factor/genetics
- MafB Transcription Factor/metabolism
- Mice
- Mice, Transgenic
- Phagocytosis/immunology
- Promoter Regions, Genetic
- Receptors, Fc/metabolism
- Receptors, Scavenger/genetics
- Spleen/immunology
- Spleen/metabolism
Collapse
Affiliation(s)
- Michiko Sato-Nishiwaki
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Yasuko Aida
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Shuichi Abe
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Yoko Shibata
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
- * E-mail:
| | - Tomomi Kimura
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Keiko Yamauchi
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Hiroyuki Kishi
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Akira Igarashi
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Sumito Inoue
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Masamichi Sato
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Osamu Nakajima
- Research Laboratory for Molecular Genetics, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| | - Isao Kubota
- Department of Cardiology, Pulmonology and Nephrology, School of Medicine, Yamagata University, Yamagata City, Yamagata, Japan
| |
Collapse
|
25
|
Human cytomegalovirus UL76 elicits novel aggresome formation via interaction with S5a of the ubiquitin proteasome system. J Virol 2013; 87:11562-78. [PMID: 23966401 DOI: 10.1128/jvi.01568-13] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
HCMV UL76 is a member of a conserved Herpesviridae protein family (Herpes_UL24) that is involved in viral production, latency, and reactivation. UL76 presents as globular aggresomes in the nuclei of transiently transfected cells. Bioinformatic analyses predict that UL76 has a propensity for aggregation and targets cellular proteins implicated in protein folding and ubiquitin-proteasome systems (UPS). Furthermore, fluorescence recovery after photobleaching experiments suggests that UL76 reduces protein mobility in the aggresome, which indicates that UL76 elicits the aggregation of misfolded proteins. Moreover, in the absence of other viral proteins, UL76 interacts with S5a, which is a major receptor of polyubiquitinated proteins for UPS proteolysis via its conserved region and the von Willebrand factor type A (VWA) domain of S5a. We demonstrate that UL76 sequesters polyubiquitinated proteins and S5a to nuclear aggresomes in biological proximity. After knockdown of endogenous S5a by RNA interference techniques, the UL76 level was only minimally affected in transiently expressing cells. However, a significant reduction in the number of cells containing UL76 nuclear aggresomes was observed, which suggests that S5a may play a key role in aggresome formation. Moreover, we show that UL76 interacts with S5a in the late phase of viral infection and that knockdown of S5a hinders the development of both the replication compartment and the aggresome. In this study, we demonstrate that UL76 induces a novel nuclear aggresome, likely by subverting S5a of the UPS. Given that UL76 belongs to a conserved family, this underlying mechanism may be shared by all members of the Herpesviridae.
Collapse
|
26
|
A novel molecular mechanism involved in multiple myeloma development revealed by targeting MafB to haematopoietic progenitors. EMBO J 2012; 31:3704-17. [PMID: 22903061 PMCID: PMC3442275 DOI: 10.1038/emboj.2012.227] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 07/20/2012] [Indexed: 12/21/2022] Open
Abstract
Transgenic expression of the MafB oncogene in haematopoietic stem/progenitor cells induces plasma cell neoplasia reminiscent of human multiple myeloma and suggests DNA methylation as cause of malignant transformation. Understanding the cellular origin of cancer can help to improve disease prevention and therapeutics. Human plasma cell neoplasias are thought to develop from either differentiated B cells or plasma cells. However, when the expression of Maf oncogenes (associated to human plasma cell neoplasias) is targeted to mouse B cells, the resulting animals fail to reproduce the human disease. Here, to explore early cellular changes that might take place in the development of plasma cell neoplasias, we engineered transgenic mice to express MafB in haematopoietic stem/progenitor cells (HS/PCs). Unexpectedly, we show that plasma cell neoplasias arise in the MafB-transgenic mice. Beyond their clinical resemblance to human disease, these neoplasias highly express genes that are known to be upregulated in human multiple myeloma. Moreover, gene expression profiling revealed that MafB-expressing HS/PCs were more similar to B cells and tumour plasma cells than to any other subset, including wild-type HS/PCs. Consistent with this, genome-scale DNA methylation profiling revealed that MafB imposes an epigenetic program in HS/PCs, and that this program is preserved in mature B cells of MafB-transgenic mice, demonstrating a novel molecular mechanism involved in tumour initiation. Our findings suggest that, mechanistically, the haematopoietic progenitor population can be the target for transformation in MafB-associated plasma cell neoplasias.
Collapse
|
27
|
Morita M, Nakamura M, Hamada M, Takahashi S. Combinatorial motif analysis of regulatory gene expression in Mafb deficient macrophages. BMC SYSTEMS BIOLOGY 2011; 5 Suppl 2:S7. [PMID: 22784578 PMCID: PMC3287487 DOI: 10.1186/1752-0509-5-s2-s7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Background Deficiency of the transcription factor MafB, which is normally expressed in macrophages, can underlie cellular dysfunction associated with a range of autoimmune diseases and arteriosclerosis. MafB has important roles in cell differentiation and regulation of target gene expression; however, the mechanisms of this regulation and the identities of other transcription factors with which MafB interacts remain uncertain. Bioinformatics methods provide a valuable approach for elucidating the nature of these interactions with transcriptional regulatory elements from a large number of DNA sequences. In particular, identification of patterns of co-occurrence of regulatory cis-elements (motifs) offers a robust approach. Results Here, the directional relationships among several functional motifs were evaluated using the Log-linear Graphical Model (LGM) after extraction and search for evolutionarily conserved motifs. This analysis highlighted GATA-1 motifs and 5’AT-rich half Maf recognition elements (MAREs) in promoter regions of 18 genes that were down-regulated in Mafb deficient macrophages. GATA-1 motifs and MafB motifs could regulate expression of these genes in both a negative and positive manner, respectively. The validity of this conclusion was tested with data from a luciferase assay that used a C1qa promoter construct carrying both the GATA-1 motifs and MAREs. GATA-1 was found to inhibit the activity of the C1qa promoter with the GATA-1 motifs and MafB motifs. Conclusions These observations suggest that both the GATA-1 motifs and MafB motifs are important for lineage specific expression of C1qa. In addition, these findings show that analysis of combinations of evolutionarily conserved motifs can be successfully used to identify patterns of gene regulation.
Collapse
Affiliation(s)
- Mariko Morita
- Department of Anatomy and Embryology, Institute of Basic Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, 305-8575, Ibaraki, Japan.
| | | | | | | |
Collapse
|
28
|
Abstract
Chondrocyte differentiation in the growth plate is an important process for the longitudinal growth of endochondral bones. Sox9 and Runx2 are the most often-studied transcriptional regulators of the chondrocyte differentiation process, but the importance of additional factors is also becoming apparent. Mafs are a subfamily of the basic ZIP (bZIP) transcription factor superfamily, which act as key regulators of tissue-specific gene expression and terminal differentiation in many tissues. There is increasing evidence that c-Maf and its splicing variant Lc-Maf play a role in chondrocyte differentiation in a temporal-spatial manner. This review summarizes the functions of c-Maf in chondrocyte differentiation and discusses the possible role of c-Maf in osteoarthritis progression.
Collapse
Affiliation(s)
| | | | - Dominik R. Haudenschild
- Dominik R. Haudenschild, Department of Orthopaedic Surgery, Division of Orthopaedic Research, University of California Davis Medical Center, 4635 Second Street, Sacramento, CA 95817, USA
| |
Collapse
|
29
|
Gosmain Y, Marthinet E, Cheyssac C, Guérardel A, Mamin A, Katz LS, Bouzakri K, Philippe J. Pax6 controls the expression of critical genes involved in pancreatic {alpha} cell differentiation and function. J Biol Chem 2010; 285:33381-33393. [PMID: 20592023 DOI: 10.1074/jbc.m110.147215] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The paired box homeodomain Pax6 is crucial for endocrine cell development and function and plays an essential role in glucose homeostasis. Indeed, mutations of Pax6 are associated with diabetic phenotype. Importantly, homozygous mutant mice for Pax6 are characterized by markedly decreased β and δ cells and absent α cells. To better understand the critical role that Pax6 exerts in glucagon-producing cells, we developed a model of primary rat α cells. To study the transcriptional network of Pax6 in adult and differentiated α cells, we generated Pax6-deficient primary rat α cells and glucagon-producing cells, using either specific siRNA or cells expressing constitutively a dominant-negative form of Pax6. In primary rat α cells, we confirm that Pax6 controls the transcription of the Proglucagon and processing enzyme PC2 genes and identify three new target genes coding for MafB, cMaf, and NeuroD1/Beta2, which are all critical for Glucagon gene transcription and α cell differentiation. Furthermore, we demonstrate that Pax6 directly binds and activates the promoter region of the three genes through specific binding sites and that constitutive expression of a dominant-negative form of Pax6 in glucagon-producing cells (InR1G9) inhibits the activities of the promoters. Finally our results suggest that the critical role of Pax6 action on α cell differentiation is independent of those of Arx and Foxa2, two transcription factors that are necessary for α cell development. We conclude that Pax6 is critical for α cell function and differentiation through the transcriptional control of key genes involved in glucagon gene transcription, proglucagon processing, and α cell differentiation.
Collapse
Affiliation(s)
- Yvan Gosmain
- From the Diabetes Unit, Division of Endocrinology, Diabetes and Nutrition, University Hospital, 1211 Geneva 4, Switzerland.
| | - Eric Marthinet
- From the Diabetes Unit, Division of Endocrinology, Diabetes and Nutrition, University Hospital, 1211 Geneva 4, Switzerland
| | - Claire Cheyssac
- From the Diabetes Unit, Division of Endocrinology, Diabetes and Nutrition, University Hospital, 1211 Geneva 4, Switzerland
| | - Audrey Guérardel
- From the Diabetes Unit, Division of Endocrinology, Diabetes and Nutrition, University Hospital, 1211 Geneva 4, Switzerland
| | - Aline Mamin
- From the Diabetes Unit, Division of Endocrinology, Diabetes and Nutrition, University Hospital, 1211 Geneva 4, Switzerland
| | - Liora S Katz
- From the Diabetes Unit, Division of Endocrinology, Diabetes and Nutrition, University Hospital, 1211 Geneva 4, Switzerland
| | - Karim Bouzakri
- Department of Genetic Medicine and Development, University Medical Center, University of Geneva, 1211 Geneva 4, Switzerland
| | - Jacques Philippe
- From the Diabetes Unit, Division of Endocrinology, Diabetes and Nutrition, University Hospital, 1211 Geneva 4, Switzerland
| |
Collapse
|
30
|
Reinke AW, Grigoryan G, Keating AE. Identification of bZIP interaction partners of viral proteins HBZ, MEQ, BZLF1, and K-bZIP using coiled-coil arrays. Biochemistry 2010; 49:1985-97. [PMID: 20102225 DOI: 10.1021/bi902065k] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Basic-region leucine-zipper transcription factors (bZIPs) contain a segment rich in basic amino acids that can bind DNA, followed by a leucine zipper that can interact with other leucine zippers to form coiled-coil homo- or heterodimers. Several viruses encode proteins containing bZIP domains, including four that encode bZIPs lacking significant homology to any human protein. We investigated the interaction specificity of these four viral bZIPs by using coiled-coil arrays to assess self-associations as well as heterointeractions with 33 representative human bZIPs. The arrays recapitulated reported viral-human interactions and also uncovered new associations. MEQ and HBZ interacted with multiple human partners and had unique interaction profiles compared to any human bZIPs, whereas K-bZIP and BZLF1 displayed homospecificity. New interactions detected included HBZ with MAFB, MAFG, ATF2, CEBPG, and CREBZF and MEQ with NFIL3. These were confirmed in solution using circular dichroism. HBZ can heteroassociate with MAFB and MAFG in the presence of MARE-site DNA, and this interaction is dependent on the basic region of HBZ. NFIL3 and MEQ have different yet overlapping DNA-binding specificities and can form a heterocomplex with DNA. Computational design considering both affinity for MEQ and specificity with respect to other undesired bZIP-type interactions was used to generate a MEQ dimerization inhibitor. This peptide, anti-MEQ, bound MEQ both stably and specifically, as assayed using coiled-coil arrays and circular dichroism in solution. Anti-MEQ also inhibited MEQ binding to DNA. These studies can guide further investigation of the function of viral and human bZIP complexes.
Collapse
Affiliation(s)
- Aaron W Reinke
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | |
Collapse
|
31
|
Gene expression profile of the third pharyngeal pouch reveals role of mesenchymal MafB in embryonic thymus development. Blood 2009; 113:2976-87. [PMID: 19164599 DOI: 10.1182/blood-2008-06-164921] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The thymus provides a microenvironment that induces the differentiation of T-progenitor cells into functional T cells and that establishes a diverse yet self-tolerant T-cell repertoire. However, the mechanisms that lead to the development of the thymus are incompletely understood. We report herein the results of screening for genes that are expressed in the third pharyngeal pouch, which contains thymic primordium. Polymerase chain reaction (PCR)-based cDNA subtraction screening for genes expressed in microdissected tissues of the third pharyngeal pouch rather than the second pharyngeal arch yielded one transcription factor, MafB, which was predominantly expressed in CD45(-)IA(-)PDGFRalpha(+) mesenchymal cells and was detectable even in the third pharyngeal pouch of FoxN1-deficient nude mice. Interestingly, the number of CD45(+) cells that initially accumulated in the embryonic thymus was significantly decreased in MafB-deficient mice. Alterations of gene expression in the embryonic thymi of MafB-deficient mice included the reduced expression of Wnt3 and BMP4 in mesenchymal cells and of CCL21 and CCL25 in epithelial cells. These results suggest that MafB expressed in third pharyngeal pouch mesenchymal cells critically regulates lymphocyte accumulation in the embryonic thymus.
Collapse
|
32
|
Biologic and genetic characterization of the novel amyloidogenic lambda light chain-secreting human cell lines, ALMC-1 and ALMC-2. Blood 2008; 112:1931-41. [PMID: 18567838 DOI: 10.1182/blood-2008-03-143040] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Primary systemic amyloidosis (AL) is a rare monoclonal plasma cell (PC) disorder characterized by the deposition of misfolded immunoglobulin (Ig) light chains (LC) in vital organs throughout the body. To our knowledge, no cell lines have ever been established from AL patients. Here we describe the establishment of the ALMC-1 and ALMC-2 cell lines from an AL patient. Both cell lines exhibit a PC phenotype and display cytokine-dependent growth. Using a comprehensive genetic approach, we established the genetic relationship between the cell lines and the primary patient cells, and we were also able to identify new genetic changes accompanying tumor progression that may explain the natural history of this patient's disease. Importantly, we demonstrate that free lambda LC secreted by both cell lines contained a beta structure and formed amyloid fibrils. Despite absolute Ig LC variable gene sequence identity, the proteins show differences in amyloid formation kinetics that are abolished by the presence of Na(2)SO(4). The formation of amyloid fibrils from these naturally secreting human LC cell lines is unprecedented. Moreover, these cell lines will provide an invaluable tool to better understand AL, from the combined perspectives of amyloidogenic protein structure and amyloid formation, genetics, and cell biology.
Collapse
|
33
|
Abraira VE, Hyun N, Tucker AF, Coling DE, Brown MC, Lu C, Hoffman GR, Goodrich LV. Changes in Sef levels influence auditory brainstem development and function. J Neurosci 2007; 27:4273-82. [PMID: 17442811 PMCID: PMC6672320 DOI: 10.1523/jneurosci.3477-06.2007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
During development of the CNS, secreted morphogens of the fibroblast growth factor (FGF) family have multiple effects on cell division, migration, and survival depending on where, when, and how much FGF signal is received. The consequences of misregulating the FGF pathway were studied in a mouse with decreased levels of the FGF antagonist Sef. To uncover effects in the nervous system, we focused on the auditory system, which is accessible to physiological analysis. We found that the mitogen-activated protein kinase pathway is active in the rhombic lip, a germinal zone that generates diverse types of neurons, including the cochlear nucleus complex of the auditory system. Sef is expressed immediately adjacent to the rhombic lip, overlapping with FGF15 and FGFR1, which is also present in the lip itself. This pattern suggests that Sef may normally function in non-rhombic lip cells and prevent them from responding to FGF ligand in the vicinity. Consistent with this idea, overexpression of Sef in chicks decreased the size of the auditory nuclei. Cochlear nucleus defects were also apparent in mice with reduced levels of Sef, with 13% exhibiting grossly dysmorphic cochlear nuclei and 26% showing decreased amounts of GFAP in the cochlear nucleus. Additional evidence for cochlear nucleus defects was obtained by electrophysiological analysis of Sef mutant mice, which have normal auditory thresholds but abnormal auditory brainstem responses. These results show both increases and decreases in Sef levels affect the assembly and function of the auditory brainstem.
Collapse
Affiliation(s)
| | | | | | - Donald E. Coling
- Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, New York 14260, and
| | - M. Christian Brown
- Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02115
| | | | | | | |
Collapse
|
34
|
Yan C, Lian X, Li Y, Dai Y, White A, Qin Y, Li H, Hume DA, Du H. Macrophage-specific expression of human lysosomal acid lipase corrects inflammation and pathogenic phenotypes in lal-/- mice. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 169:916-26. [PMID: 16936266 PMCID: PMC1698822 DOI: 10.2353/ajpath.2006.051327] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lysosomal acid lipase (LAL) hydrolyzes cholesteryl esters and triglycerides to generate free fatty acids and cholesterol in the cell. The downstream metabolites of these compounds serve as hormonal ligands for nuclear receptors and transcription factors. Genetic ablation of the lal gene in the mouse caused malformation of macrophages and inflammation-triggered multiple pathogenic phenotypes in multiple organs. To assess the relationship between macrophages and lal-/- pathogenic phenotypes, a macrophage-specific doxycycline-inducible transgenic system was generated to induce human LAL (hLAL) expression in the lal-/- genetic background under control of the 7.2-kb c-fms promoter/intron2 regulatory sequence. Doxycycline-induced hLAL expression in macrophages significantly ameliorated aberrant gene expression, inflammatory cell (neutrophil) influx, and pathogenesis in multiple organs. These studies strongly support that neutral lipid metabolism in macrophages contributes to organ inflammation and pathogenesis.
Collapse
Affiliation(s)
- Cong Yan
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, and Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Aziz A, Vanhille L, Mohideen P, Kelly LM, Otto C, Bakri Y, Mossadegh N, Sarrazin S, Sieweke MH. Development of macrophages with altered actin organization in the absence of MafB. Mol Cell Biol 2006; 26:6808-18. [PMID: 16943423 PMCID: PMC1592864 DOI: 10.1128/mcb.00245-06] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In the hematopoietic system the bZip transcription factor MafB is selectively expressed at high levels in monocytes and macrophages and promotes macrophage differentiation in myeloid progenitors, whereas a dominant-negative allele can inhibit this process. To analyze the requirement of MafB for macrophage development, we generated MafB-deficient mice and, due to their neonatal lethal phenotype, analyzed macrophage differentiation in vitro, in the embryo, and in reconstituted mice. Surprisingly we observed in vitro differentiation of macrophages from E14.5 fetal liver (FL) cells and E18.5 splenocytes. Furthermore we found normal numbers of F4/80(+)/Mac-1(+) macrophages and monocytes in fetal liver, spleen, and blood as well as in bone marrow, spleen, and peritoneum of adult MafB(-/-) FL reconstituted mice. MafB(-/-) macrophages showed intact basic macrophage functions such as phagocytosis of latex beads or Listeria monocytogenes and nitric oxide production in response to lipopolysaccharide. By contrast, MafB(-/-) macrophages expressed increased levels of multiple genes involved in actin organization. Consistent with this, phalloidin staining revealed an altered morphology involving increased numbers of branched protrusions of MafB(-/-) macrophages in response to macrophage colony-stimulating factor. Together these data point to an unexpected redundancy of MafB function in macrophage differentiation and a previously unknown role in actin-dependent macrophage morphology.
Collapse
Affiliation(s)
- Athar Aziz
- Centre d'Immunologie de Marseille-Luminy, Campus de Luminy, Case 906, 13288 Marseille Cedex 09, France
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Moriguchi T, Hamada M, Morito N, Terunuma T, Hasegawa K, Zhang C, Yokomizo T, Esaki R, Kuroda E, Yoh K, Kudo T, Nagata M, Greaves DR, Engel JD, Yamamoto M, Takahashi S. MafB is essential for renal development and F4/80 expression in macrophages. Mol Cell Biol 2006; 26:5715-27. [PMID: 16847325 PMCID: PMC1592773 DOI: 10.1128/mcb.00001-06] [Citation(s) in RCA: 160] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
MafB is a member of the large Maf family of transcription factors that share similar basic region/leucine zipper DNA binding motifs and N-terminal activation domains. Although it is well known that MafB is specifically expressed in glomerular epithelial cells (podocytes) and macrophages, characterization of the null mutant phenotype in these tissues has not been previously reported. To investigate suspected MafB functions in the kidney and in macrophages, we generated mafB/green fluorescent protein (GFP) knock-in null mutant mice. MafB homozygous mutants displayed renal dysgenesis with abnormal podocyte differentiation as well as tubular apoptosis. Interestingly, these kidney phenotypes were associated with diminished expression of several kidney disease-related genes. In hematopoietic cells, GFP fluorescence was observed in both Mac-1- and F4/80-expressing macrophages in the fetal liver. Interestingly, F4/80 expression in macrophages was suppressed in the homozygous mutant, although development of the Mac-1-positive macrophage population was unaffected. In primary cultures of fetal liver hematopoietic cells, MafB deficiency was found to dramatically suppress F4/80 expression in nonadherent macrophages, whereas the Mac-1-positive macrophage population developed normally. These results demonstrate that MafB is essential for podocyte differentiation, renal tubule survival, and F4/80 maturation in a distinct subpopulation of nonadherent mature macrophages.
Collapse
Affiliation(s)
- Takashi Moriguchi
- Institute of Basic Medical Sciences, Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8575, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Garcia-Dominguez M, Gilardi-Hebenstreit P, Charnay P. PIASxbeta acts as an activator of Hoxb1 and is antagonized by Krox20 during hindbrain segmentation. EMBO J 2006; 25:2432-42. [PMID: 16675951 PMCID: PMC1478176 DOI: 10.1038/sj.emboj.7601122] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Accepted: 04/06/2006] [Indexed: 11/09/2022] Open
Abstract
The zinc-finger transcription factor Krox20 constitutes a key regulator of hindbrain development, essential for the formation and specification of rhombomeres (r) 3 and 5. It is in particular responsible for the respective activation and repression of odd- and even-numbered rhombomere-specific genes, which include Hox genes. In this study, we have identified PIASxbeta as a novel direct interactor of Krox20. In addition, we found that PIASxbeta is able to activate the r4-specific gene Hoxb1. Binding of Krox20 prevents this activation, providing a molecular basis for the repression of Hoxb1 by Krox20. The same domain in the Krox20 protein, the zinc-fingers, is involved in DNA binding for transcriptional activation and in interaction with PIASxbeta for transcriptional repression, although the actual precise contacts are different. Our findings add an additional level in the complexity of Hox gene regulation and provide an example of how a single regulator can coordinate the activation and repression of a set of genes by very different mechanisms, acting as a molecular switch to specify cell identity and fate.
Collapse
Affiliation(s)
- Mario Garcia-Dominguez
- INSERM, U 784, Ecole Normale Supérieure, Paris, France
- Instituto de Bioquimica Vegetal y Fotosintesis, Isla de la Cartuja, Sevilla, Spain
| | | | | |
Collapse
|
38
|
Pouponnot C, Sii-Felice K, Hmitou I, Rocques N, Lecoin L, Druillennec S, Felder-Schmittbuhl MP, Eychène A. Cell context reveals a dual role for Maf in oncogenesis. Oncogene 2006; 25:1299-310. [PMID: 16247450 DOI: 10.1038/sj.onc.1209171] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Maf b-Zip transcription factors are involved in both terminal differentiation and oncogenesis. To investigate this apparent contradiction, we used two different primary cell types and performed an extensive analysis of transformation parameters induced by Maf proteins. We show that MafA and c-Maf are potent oncogenes in chicken embryo fibroblasts, while MafB appears weaker. We also provide the first evidence that MafA can confer growth factor independence and promote cell division at low density. Moreover, using MafA as a model, we identified several parameters that are critical for Maf transforming activities. Indeed, MafA ability to induce anchorage-independent cell growth was sensitive to culture conditions. In addition, the transforming activity of MafA was dependent on its phosphorylation state, since mutation on Ser65 impaired its ability to induce growth at low density and anchorage-independent growth. We next examined transforming activity of large Maf proteins in embryonic neuroretina cells, where they are known to induce differentiation. Unlike v-Jun, MafA, MafB and c-Maf did not show oncogenic activity in these cells. Moreover, they counteracted transformation induced by constitutive activation of the Ras/Raf/MEK pathway. Taken together, our results show that Maf proteins could display antagonistic functions in oncogenesis depending on the cellular context, and support a dual role for Maf as both oncogenes and tumor suppressor-like proteins.
Collapse
Affiliation(s)
- C Pouponnot
- Institut Curie, CNRS UMR 146, Centre Universitaire, Laboratoire 110, Orsay Cedex, France.
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Suzuki A, Iida S, Kato-Uranishi M, Tajima E, Zhan F, Hanamura I, Huang Y, Ogura T, Takahashi S, Ueda R, Barlogie B, Shaughnessy J, Esumi H. ARK5 is transcriptionally regulated by the Large-MAF family and mediates IGF-1-induced cell invasion in multiple myeloma: ARK5 as a new molecular determinant of malignant multiple myeloma. Oncogene 2006; 24:6936-44. [PMID: 16044163 DOI: 10.1038/sj.onc.1208844] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
ARK5, AMP-activated protein kinase (AMPK)-related protein kinase mediating Akt signals, is closely involved in tumor progression, and its stage-associated expression was observed in colorectal cancer. In this study, we found ARK5 expression in multiple myeloma cell lines expressing c-MAF and MAFB. In addition, gene expression profiling of 351 clinical specimens revealed ARK5 expression in primary myelomas expressing c-MAF and MAFB, suggesting that ARK5 may be a transcriptional target of the Large-MAF family. Sequence analysis of the ARK5 gene promoter revealed that it contains two putative MAF-recognition element (MARE) sequences. In support of this hypothesis, ARK5 was induced when an MAFB or c-MAF expression vector was introduced into non-ARK5-expressing colon cancer cells. Furthermore, ARK5 promoter activity was dramatically decreased by mutation or deletion of MARE sequences. Chromatin immunoprecipitation assays revealed an interaction between the Large-MAF family proteins and MARE sequences in the ARK5 promoter. Moreover, in ARK5 mRNA-expressing multiple myeloma lines, but not in ARK5-negative lines, insulin-like growth factor (IGF)-1 increased invasion activity. IGF-1-induced invasion was reproduced when ARK5 was overexpressed in Burkitt's lymphoma and plasmacytoma lines. Based on results, we conclude that ARK5 is a transcriptional target of the Large-MAF family through MARE sequence and that ARK5 may in part mediate the aggressive phenotype associated with c-MAF- and MAFB-expressing myelomas.
Collapse
Affiliation(s)
- Atsushi Suzuki
- Cancer Physiology Project, National Cancer Center Research Institute East, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Lian X, Yan C, Qin Y, Knox L, Li T, Du H. Neutral lipids and peroxisome proliferator-activated receptor-{gamma} control pulmonary gene expression and inflammation-triggered pathogenesis in lysosomal acid lipase knockout mice. THE AMERICAN JOURNAL OF PATHOLOGY 2005; 167:813-21. [PMID: 16127159 PMCID: PMC1698726 DOI: 10.1016/s0002-9440(10)62053-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The functional roles of neutral lipids in the lung are poorly understood. However, blocking cholesteryl ester and triglyceride metabolism in lysosomal acid lipase gene knockout mice (lal-/-) results in severe pathogenic phenotypes in the lung, including massive neutrophil infiltration, foamy macrophage accumulation, unwanted cell growth, and emphysema. To elucidate the mechanism underlining these pathologies, we performed Affymetrix GeneChip microarray analysis of 1-, 3-, and 6-month-old mice and identified aberrant gene expression that progressed with age. Among changed genes, matrix metalloproteinase (MMP)-12, apoptosis inhibitor 6 (Api-6), erythroblast transformation-specific domain (Ets) transcription factor family member Spi-C, and oncogene MafB were increased 100-, 70-, 40-, and 10-fold, respectively, in lal-/- lungs versus the wild-type lungs. The pathogenic increases of these molecules occurred primarily in alveolar type II epithelial cells. Transcriptional activities of the MMP-12 and Api-6 promoters were stimulated by Spi-C or MafB in respiratory epithelial cells. Treatment with 9-hydroxyoctadecanoic acids and ciglitazone significantly rescued lal-/- pulmonary inflammation and aberrant gene expression. In addition, both compounds as well as peroxisome proliferator-activated receptor gamma inhibited MMP-12 and Api-6 promoter activities. These data suggest that inflammation-triggered cell growth and emphysema during lysosomal acid lipase deficiency are partially caused by peroxisome proliferator-activated receptor-gamma inactivation.
Collapse
Affiliation(s)
- Xuemei Lian
- Division of Pulmonary Biology, or Hong Du, Ph.D., Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA
| | | | | | | | | | | |
Collapse
|
41
|
Zhang C, Moriguchi T, Kajihara M, Esaki R, Harada A, Shimohata H, Oishi H, Hamada M, Morito N, Hasegawa K, Kudo T, Engel JD, Yamamoto M, Takahashi S. MafA is a key regulator of glucose-stimulated insulin secretion. Mol Cell Biol 2005; 25:4969-76. [PMID: 15923615 PMCID: PMC1140590 DOI: 10.1128/mcb.25.12.4969-4976.2005] [Citation(s) in RCA: 355] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
MafA is a transcription factor that binds to the promoter in the insulin gene and has been postulated to regulate insulin transcription in response to serum glucose levels, but there is no current in vivo evidence to support this hypothesis. To analyze the role of MafA in insulin transcription and glucose homeostasis in vivo, we generated MafA-deficient mice. Here we report that MafA mutant mice display intolerance to glucose and develop diabetes mellitus. Detailed analyses revealed that glucose-, arginine-, or KCl-stimulated insulin secretion from pancreatic beta cells is severely impaired, although insulin content per se is not significantly affected. MafA-deficient mice also display age-dependent pancreatic islet abnormalities. Further analysis revealed that insulin 1, insulin 2, Pdx1, Beta2, and Glut-2 transcripts are diminished in MafA-deficient mice. These results show that MafA is a key regulator of glucose-stimulated insulin secretion in vivo.
Collapse
Affiliation(s)
- Chuan Zhang
- Institute of Basic Medical Sciences and Laboratory Animal Resource Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Yoshida T, Ohkumo T, Ishibashi S, Yasuda K. The 5'-AT-rich half-site of Maf recognition element: a functional target for bZIP transcription factor Maf. Nucleic Acids Res 2005; 33:3465-78. [PMID: 15972792 PMCID: PMC1156962 DOI: 10.1093/nar/gki653] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The Maf family of proteins are a subgroup of basic region-leucine zipper (bZIP) transcription factors, which recognize a long palindromic DNA sequence [TGCTGAC(G)TCAGCA] known as the Maf recognition element (MARE). Interestingly, the functional target enhancer sequences present in the alphaA-crystallin gene contain a well-conserved half-site of MARE rather than the entire palindromic sequence. To resolve how Maf proteins bind to target sequences containing only MARE half-sites, we examined their binding activities using electrophoretic gel mobility shift assays as well as in vitro and in vivo reporter assays. Our results indicate that the 5'-flanking region of the MARE half-site is required for Maf proteins to bind both in vitro and in vivo. The critical 5'-flanking sequences for c-Maf were determined by a selection and amplification binding assay and show a preference for AT-rich nucleotides. Furthermore, sequence analysis of the regulatory regions of several target genes also suggests that AT-rich sequences are important. We conclude that Maf can bind to at least two types of target sequences, the classical MARE (palindrome type) and a 5'-AT-rich MARE half-site (half-site type). Our results provide important new insights into the DNA binding and site selection by bZIP transcription factors.
Collapse
Affiliation(s)
- Tomonori Yoshida
- Graduate School of Biological Sciences, Nara Institute of Science and Technology Takayama 8916-5, Ikoma, Nara, 630-0101, Japan.
| | | | | | | |
Collapse
|
43
|
Coolen M, Sii-Felice K, Bronchain O, Mazabraud A, Bourrat F, Rétaux S, Felder-Schmittbuhl MP, Mazan S, Plouhinec JL. Phylogenomic analysis and expression patterns of large Maf genes in Xenopus tropicalis provide new insights into the functional evolution of the gene family in osteichthyans. Dev Genes Evol 2005; 215:327-39. [PMID: 15759153 DOI: 10.1007/s00427-005-0476-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2004] [Accepted: 02/15/2005] [Indexed: 10/25/2022]
Abstract
We have performed an exhaustive characterization of the large Maf family of basic leucine zipper transcription factors in vertebrates using the genome data available, and studied the embryonic expression patterns of the four paralogous genes thus identified in Xenopus tropicalis. Our phylogenetic analysis shows that, in osteichthyans, the large Maf family contains four orthology classes, MafA, MafB, c-Maf and Nrl, which have emerged in vertebrates prior to the split between actinopterygians and sarcopterygians. It leads to the unambiguous assignment of the Xenopus laevis XLmaf gene, previously considered a MafA orthologue, to the Nrl class, the identification of the amphibian MafA and c-Maf orthologues and the identification of the zebrafish Nrl gene. The four X. tropicalis paralogues display partially redundant but nevertheless distinct expression patterns in the somites, developing hindbrain, pronephros, ventral blood island and lens. Comparisons with the data available in the mouse, chick and zebrafish show that these large Maf expression territories are highly conserved among osteichthyans but also highlight a number of differences in the timing of large Maf gene expression, the precise extent of some labelled territories and the combinations of paralogues transcribed in some organs. In particular, the availability of robust phylogenies leads to a reinterpretation of previous expression pattern comparisons, suggesting an important part for function shuffling within the gene family in the developing lens. These data highlight the importance of exhaustive characterizations of gene families for comparative analyses of the genetic mechanisms, which control developmental processes in vertebrates.
Collapse
Affiliation(s)
- M Coolen
- Développement et Evolution des Vertébrés, UMR8080, Université Paris-Sud, 91405 Orsay cédex, France
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Nishizawa M, Kataoka K, Vogt PK. MafA has strong cell transforming ability but is a weak transactivator. Oncogene 2003; 22:7882-90. [PMID: 12970735 DOI: 10.1038/sj.onc.1206526] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The maf oncogene of the avian oncogenic retrovirus AS42 encodes a nuclear bZip protein, v-Maf, that recognizes sequences related to the AP-1 target site. The corresponding cellular protein, c-Maf belongs to a family of related bZip proteins together with MafA and MafB. In this paper, we compare the transactivation and cell transforming abilities of MafA and MafB along with two forms of the c-Maf protein. These proteins induce cellular transformation when expressed in chicken embryo fibroblasts. In reporter assays, MafA is a much less effective transactivator than the other Maf proteins, but unexpectedly shows the strongest activity in cell transformation. Chimeras of MafA and MafB correlate the strong cell transforming ability of MafA with its DNA-binding domain. The DNA-binding domain of MafA is also correlated with weak transactivation. Additional mutagenesis experiments show that transactivation and transformation by MafA are also controlled by phosphorylation of two conserved serine residues in the transactivation domain. Finally, we constructed MafA-estrogen receptor fusion molecules that show tightly hormone-dependent cell transforming ability. These regulatable constructs permit a kinetic characterization of target gene responses and facilitate discrimination between direct and indirect targets.
Collapse
Affiliation(s)
- Makoto Nishizawa
- Department of Molecular and Experimental Medicine, BCC239, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | | | | |
Collapse
|
45
|
Tkach V, Tulchinsky E, Lukanidin E, Vinson C, Bock E, Berezin V. Role of the Fos family members, c-Fos, Fra-1 and Fra-2, in the regulation of cell motility. Oncogene 2003; 22:5045-54. [PMID: 12902987 DOI: 10.1038/sj.onc.1206570] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The AP-1 transcription factor is composed of members of the Fos, Jun and ATF families, and plays a key role in tumor progression. We investigated whether Fos proteins regulate cell motility, and if so, whether this capacity is related to their transactivation potential. Two cell lines with different expression profiles of AP-1 were employed focusing on the Fos-family members c-Fos, Fra-1 and Fra-2. Transactivation motifs are found in c-Fos, but not in Fra-1 or Fra-2. The adenocarcinoma CSML0 cells display a low motility and do not express Fra-1 or Fra-2, and only very little c-Fos. In contrast, the fibroblastoid L929 cells express both Fra-1 and Fra-2, but no c-Fos, and these cells display a high motility. Transfection with Fra-1 or c-Fos, but not with Fra-2, strongly enhanced the motility of CSML0 cells. The effect of Fra-1 required the presence of the N-terminal domain of this protein. Conversely, transfection with a Fos dominant-negative mutant or with anti-sense fra-1 or fra-2, strongly reduced the motility of L929 cells. Changes in cell motility correlated with the morphological appearance and the degree of contact with the substratum. We conclude that Fos proteins have distinct roles in the regulation of cell motility.
Collapse
Affiliation(s)
- Vadim Tkach
- Protein Laboratory, Institute of Molecular Pathology, School of Medicine, Copenhagen University, DK-2200 Copenhagen, Denmark
| | | | | | | | | | | |
Collapse
|
46
|
Sukhodolets KE, Hickman AB, Agarwal SK, Sukhodolets MV, Obungu VH, Novotny EA, Crabtree JS, Chandrasekharappa SC, Collins FS, Spiegel AM, Burns AL, Marx SJ. The 32-kilodalton subunit of replication protein A interacts with menin, the product of the MEN1 tumor suppressor gene. Mol Cell Biol 2003; 23:493-509. [PMID: 12509449 PMCID: PMC151531 DOI: 10.1128/mcb.23.2.493-509.2003] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Menin is a 70-kDa protein encoded by MEN1, the tumor suppressor gene disrupted in multiple endocrine neoplasia type 1. In a yeast two-hybrid system based on reconstitution of Ras signaling, menin was found to interact with the 32-kDa subunit (RPA2) of replication protein A (RPA), a heterotrimeric protein required for DNA replication, recombination, and repair. The menin-RPA2 interaction was confirmed in a conventional yeast two-hybrid system and by direct interaction between purified proteins. Menin-RPA2 binding was inhibited by a number of menin missense mutations found in individuals with multiple endocrine neoplasia type 1, and the interacting regions were mapped to the N-terminal portion of menin and amino acids 43 to 171 of RPA2. This region of RPA2 contains a weak single-stranded DNA-binding domain, but menin had no detectable effect on RPA-DNA binding in vitro. Menin bound preferentially in vitro to free RPA2 rather than the RPA heterotrimer or a subcomplex consisting of RPA2 bound to the 14-kDa subunit (RPA3). However, the 70-kDa subunit (RPA1) was coprecipitated from HeLa cell extracts along with RPA2 by menin-specific antibodies, suggesting that menin binds to the RPA heterotrimer or a novel RPA1-RPA2-containing complex in vivo. This finding was consistent with the extensive overlap in the nuclear localization patterns of endogenous menin, RPA2, and RPA1 observed by immunofluorescence.
Collapse
Affiliation(s)
- Karen E Sukhodolets
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-1802, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Vinson C, Myakishev M, Acharya A, Mir AA, Moll JR, Bonovich M. Classification of human B-ZIP proteins based on dimerization properties. Mol Cell Biol 2002; 22:6321-35. [PMID: 12192032 PMCID: PMC135624 DOI: 10.1128/mcb.22.18.6321-6335.2002] [Citation(s) in RCA: 333] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Charles Vinson
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
| | | | | | | | | | | |
Collapse
|
48
|
Dhakshinamoorthy S, Jaiswal AK. c-Maf negatively regulates ARE-mediated detoxifying enzyme genes expression and anti-oxidant induction. Oncogene 2002; 21:5301-12. [PMID: 12149651 DOI: 10.1038/sj.onc.1205642] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2002] [Revised: 04/24/2002] [Accepted: 04/29/2002] [Indexed: 12/30/2022]
Abstract
Anti-oxidant response element (ARE) and nuclear factors including Nrf2 and small Maf (MafG and MafK) proteins are known to regulate expression and induction of detoxifying enzyme genes including quinone oxidoreductase1 (NQO1). Nrf2 upregulates and small Maf proteins lacking the transcriptional activation domain down regulates ARE-mediated expression and induction. In this report, we have investigated the role of c-Maf (large Maf) containing the transcriptional activation domain in the regulation of ARE-mediated genes expression. The overexpression of c-Maf in human hepatoblastoma (Hep-G2) cells led to the repression of ARE-mediated NQO1 and GST Ya genes expression and induction in response to tert-butyl hydroquinone (t-BHQ). This was in contrast to the role of c-Maf in the activation of Maf recognition element (MARE) mediated p53 gene expression. Deletion of transcriptional activation domain of c-Maf (ĉ-Maf) led to significant loss of MARE-mediated p53 gene expression but had no effect on the repression of ARE-mediated NQO1 gene expression. The overexpression of MafG in Hep-G2 cells repressed both ARE and MARE-mediated genes expression. The co-expression of c-Maf with MafG rescued the MafG repression of MARE but not ARE-mediated gene expression. Band and super shift assays showed the presence of c-Maf in the ARE-nuclear protein complex. Similar assays with in vitro translated proteins revealed that both c-Maf and ĉ-Maf bound to NQO1 gene ARE as homodimers and heterodimers with small Maf but not as heterodimers with Nrf2. Mutational analysis of the NQO1 gene ARE indicated that core ARE sequence is essential for binding of c-Maf leading to repression of NQO1 gene expression. Northern analysis revealed that c-Maf expression increases 2 h after t-BHQ treatment. It reached a plateau at 4 h after t-BHQ treatment. The results together led to the conclusion that c-Maf negatively regulates ARE-mediated detoxifying enzyme genes expression and induction in response to anti-oxidants.
Collapse
|
49
|
Abstract
Granulocytes and monocytes develop from a common myeloid progenitor. Early granulopoiesis requires the C/EBPalpha, PU.1, RAR, CBF, and c-Myb transcription factors, and terminal neutrophil differentiation is dependent upon C/EBPepsilon, PU.1, Sp1, CDP, and HoxA10. Monopoiesis can be induced by Maf-B, c-Jun, or Egr-1 and is dependent upon PU.1, Sp1, and ICSBP. Signals eminating from cytokine receptors modulate factor activities but do not determine cell fates. Orchestration of the myeloid developmental program is achieved via cooperative gene regulation, via synergistic and inhibitory protein-protein interactions, via promoter auto-regulation and cross-regulation, via regulation of factor levels, and via induction of cell cycle arrest: For example, c-Myb and C/EBPalpha cooperate to activate the mim-1 and NE promoters, PU.1, C/EBPalpha, and CBF, regulate the NE, MPO, and M-CSF Receptor genes. PU.1:GATA-1 interaction and C/EBP suppression of FOG transcription inhibits erythroid and megakaryocyte gene expression. c-Jun:PU.1, ICSBP:PU.1, and perhaps Maf:Jun complexes induce monocytic genes. PU.1 and C/EBPalpha activate their own promoters, C/EBPalpha rapidly induces PU.1 and C/EBPepsilon RNA expression, and RARalpha activates the C/EBPepsilon promoter. Higher levels of PU.1 are required for monopoiesis than for B-lymphopoiesis, and higher C/EBP levels may favor granulopoiesis over monopoiesis. CBF and c-Myb stimulate proliferation whereas C/EBPalpha induces a G1/S arrest; cell cycle arrest is required for terminal myelopoiesis, perhaps due to expression of p53 or hypo-phosphorylated Rb.
Collapse
Affiliation(s)
- Alan D Friedman
- Division of Pediatric Oncology, Johns Hopkins University, Baltimore, Maryland, MD 21231, USA.
| |
Collapse
|
50
|
Benkhelifa S, Provot S, Nabais E, Eychène A, Calothy G, Felder-Schmittbuhl MP. Phosphorylation of MafA is essential for its transcriptional and biological properties. Mol Cell Biol 2001; 21:4441-52. [PMID: 11416124 PMCID: PMC87104 DOI: 10.1128/mcb.21.14.4441-4452.2001] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We previously described the identification of quail MafA, a novel transcription factor of the Maf bZIP (basic region leucine zipper) family, expressed in the differentiating neuroretina (NR). In the present study, we provide the first evidence that MafA is phosphorylated and that its biological properties strongly rely upon phosphorylation of serines 14 and 65, two residues located in the transcriptional activating domain within a consensus for phosphorylation by mitogen-activated protein kinases and which are conserved among Maf proteins. These residues are phosphorylated by ERK2 but not by p38, JNK, and ERK5 in vitro. However, the contribution of the MEK/ERK pathway to MafA phosphorylation in vivo appears to be moderate, implicating another kinase. The integrity of serine 14 and serine 65 residues is required for transcriptional activity, since their mutation into alanine severely impairs MafA capacity to activate transcription. Furthermore, we show that the MafA S14A/S65A mutant displays reduced capacity to induce expression of QR1, an NR-specific target of Maf proteins. Likewise, the integrity of serines 14 and 65 is essential for the MafA ability to stimulate expression of crystallin genes in NR cells and to induce NR-to-lens transdifferentiation. Thus, the MafA capacity to induce differentiation programs is dependent on its phosphorylation.
Collapse
Affiliation(s)
- S Benkhelifa
- UMR 146 CNRS-Institut Curie, Centre Universitaire, 91405 Orsay cedex, France
| | | | | | | | | | | |
Collapse
|