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Myers G, Sun Y, Wang Y, Benmhammed H, Cui S. Roles of Nuclear Orphan Receptors TR2 and TR4 during Hematopoiesis. Genes (Basel) 2024; 15:563. [PMID: 38790192 PMCID: PMC11121135 DOI: 10.3390/genes15050563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/24/2024] [Accepted: 04/26/2024] [Indexed: 05/26/2024] Open
Abstract
TR2 and TR4 (NR2C1 and NR2C2, respectively) are evolutionarily conserved nuclear orphan receptors capable of binding direct repeat sequences in a stage-specific manner. Like other nuclear receptors, TR2 and TR4 possess important roles in transcriptional activation or repression with developmental stage and tissue specificity. TR2 and TR4 bind DNA and possess the ability to complex with available cofactors mediating developmental stage-specific actions in primitive and definitive erythrocytes. In erythropoiesis, TR2 and TR4 are required for erythroid development, maturation, and key erythroid transcription factor regulation. TR2 and TR4 recruit and interact with transcriptional corepressors or coactivators to elicit developmental stage-specific gene regulation during hematopoiesis.
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Affiliation(s)
- Greggory Myers
- Departments of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48105, USA; (G.M.); (Y.W.)
| | - Yanan Sun
- Section of Hematology-Medical Oncology, Department of Medicine, Boston University Chobanian & Avedisian School of Medicine, Boston Medical Center, Boston, MA 02118, USA; (Y.S.); (H.B.)
| | - Yu Wang
- Departments of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48105, USA; (G.M.); (Y.W.)
| | - Hajar Benmhammed
- Section of Hematology-Medical Oncology, Department of Medicine, Boston University Chobanian & Avedisian School of Medicine, Boston Medical Center, Boston, MA 02118, USA; (Y.S.); (H.B.)
| | - Shuaiying Cui
- Section of Hematology-Medical Oncology, Department of Medicine, Boston University Chobanian & Avedisian School of Medicine, Boston Medical Center, Boston, MA 02118, USA; (Y.S.); (H.B.)
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Impact of Genetic Polymorphisms in Modifier Genes in Determining Fetal Hemoglobin Levels in Beta-Thalassemia. THALASSEMIA REPORTS 2023. [DOI: 10.3390/thalassrep13010009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023] Open
Abstract
Genetic polymorphisms in Quantitative Trait Loci (QTL) genes such as BCL11A, HBS1L-MYB and KLF1 have been reported to influence fetal hemoglobin (HbF) levels. This prospective study was planned to evaluate the role of genetic polymorphisms in QTL genes as determinant of HbF levels in beta thalassemia major patients. The study was carried out on 100 thalassemia major patients. Blood samples were collected in EDTA and plain vials for biochemical and molecular evaluation. The BCL11A, HBS1L-MYB and KLF1 genotypes were determined using a polymerase chain reaction (PCR)-based method. Red Blood Cell (RBC) indices and HbF levels were assessed. In silico analysis was assessed using loss-of-function tool (Lof Tool). Statistical difference and genetic comparisons between groups were evaluated by using SPSS for Windows, version 16.0 (SPSS Inc., Chicago, IL, USA). Comparisons between quantitative variables were carried out after data explored for normality using Kolmogorov–Smirnov test of normality. Logistic regression was used for computation of ORs and 95% CIs (Confidence Interval). We observed association of HbF levels in thalassemia major patients with the polymorphisms in BCL11A (rs11886868 rs7557939; rs1427407 and rs766432) and HBS1L-MYB (rs9399137) gene. The results of this study indicated that the presence of polymorphisms on modifier genes are strongly associated with an increase in HbF levels in thalassemia major patients. Further research with a larger sample size and with other genes of modifier genes is required.
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EKLF/Klf1 regulates erythroid transcription by its pioneering activity and selective control of RNA Pol II pause-release. Cell Rep 2022; 41:111830. [PMID: 36543143 PMCID: PMC9879271 DOI: 10.1016/j.celrep.2022.111830] [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: 08/18/2022] [Revised: 10/06/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
EKLF/Klf1 is a zinc-finger transcription activator essential for erythroid lineage commitment and terminal differentiation. Using ChIP-seq, we investigate EKLF DNA binding and transcription activation mechanisms during mouse embryonic erythropoiesis. We utilize the Nan/+ mouse that expresses the EKLF-E339D (Nan) variant mutated in its conserved zinc-finger region and address the mechanism of hypomorphic and neomorphic changes in downstream gene expression. First, we show that Nan-EKLF limits normal EKLF binding to a subset of its sites. Second, we find that ectopic binding of Nan-EKLF occurs largely at enhancers and activates transcription through pioneering activity. Third, we find that for a subset of ectopic targets, gene activation is achieved in Nan/+ only by Nan-EKLF binding to distal enhancers, leading to RNA polymerase II pause-release. These results have general applicability to understanding how a DNA binding variant factor confers dominant disruptive effects on downstream gene expression even in the presence of its normal counterpart.
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Raza SHA, Pant SD, Wani AK, Mohamed HH, Khalifa NE, Almohaimeed HM, Alshanwani AR, Assiri R, Aggad WS, Noreldin AE, Abdelnour SA, Wang Z, Zan L. Krüppel-like factors family regulation of adipogenic markers genes in bovine cattle adipogenesis. Mol Cell Probes 2022; 65:101850. [PMID: 35988893 DOI: 10.1016/j.mcp.2022.101850] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 08/13/2022] [Accepted: 08/13/2022] [Indexed: 02/07/2023]
Abstract
Intramuscular fat (IMF) content is a crucial determinant of meat quality traits in livestock. A network of transcription factors act in concert to regulate adipocyte formation and differentiation, which in turn influences intramuscular fat. Several genes and associated transcription factors have been reported to influence lipogenesis and adipogenesis during fetal and subsequent growth stage. Specifically in cattle, Krüppel-like factors (KLFs), which represents a family of transcription factors, have been reported to be involved in adipogenic differentiation and development. KLFs are a relatively large group of zinc-finger transcription factors that have a variety of functions in addition to adipogenesis. In mammals, the participation of KLFs in cell development and differentiation is well known. Specifically in the context of adipogenesis, KLFs function either as positive (KLF4, KLF5, KLF6, KLF8, KLF9, KLF10, KLF11, KLF12, KLF13, KLF14 and KLF15) or negative organizers (KLF2, KLF3 and KLF7), by a variety of different mechanisms such as crosstalk with C/EBP and PPARγ. In this review, we aim to summarize the potential functions of KLFs in regulating adipogenesis and associated pathways in cattle. Furthermore, the function of known bovine adipogenic marker genes, and associated transcription factors that regulate the expression of these marker genes is also summarized. Overall, this review will provide an overview of marker genes known to influence bovine adipogenesis and regulation of expression of these genes, to provide insights into leveraging these genes and transcription factors to enhance breeding programs, especially in the context of IMF deposition and meat quality.
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Affiliation(s)
- Sayed Haidar Abbas Raza
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, PR China.
| | - Sameer D Pant
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia
| | - Atif Khurshid Wani
- Department of Biotechnology, School of Bioengineering and Biosciences, Lovely Professional University, Punjab, (144411), India
| | - Hadeer H Mohamed
- Department of Biochemistry, Faculty of Veterinary Medicine, Damanhour University, Damanhour, 22511, Egypt
| | - Norhan E Khalifa
- Department of Physiology, Faculty of Veterinary Medicine, Fuka, Matrouh University, Matrouh, 51744, Egypt
| | - Hailah M Almohaimeed
- Department of Basic Science, College of Medicine, Princess Nourah bint Abdulrahman University, P.O.Box 84428, Riyadh, 11671, Saudi Arabia
| | - Aliah R Alshanwani
- Physiology Department, College of Medicine, King Saud University, Saudi Arabia
| | - Rasha Assiri
- Department of Basic Medical Sciences, College of Medicine, Princess Nourah Bint Abdulrahman University, Riyadh, 11671, Saudi Arabia
| | - Waheeb S Aggad
- Department of Anatomy, College of Medicine, University of Jeddah, P.O. Box 8304, Jeddah, 23234, Saudi Arabia
| | - Ahmed E Noreldin
- Histology and Cytology Department, Faculty of Veterinary Medicine, Damanhour University, Damanhour, 22511, Egypt
| | - Sameh A Abdelnour
- Department of Animal Production, Faculty of Agriculture, Zagazig University, Zagazig, 44511, Egypt
| | - Zhe Wang
- Shanghai Collaborative Innovation Center of Agri-Seeds/School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, PR China.
| | - Linsen Zan
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, PR China.
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King AJ, Songdej D, Downes DJ, Beagrie RA, Liu S, Buckley M, Hua P, Suciu MC, Marieke Oudelaar A, Hanssen LLP, Jeziorska D, Roberts N, Carpenter SJ, Francis H, Telenius J, Olijnik AA, Sharpe JA, Sloane-Stanley J, Eglinton J, Kassouf MT, Orkin SH, Pennacchio LA, Davies JOJ, Hughes JR, Higgs DR, Babbs C. Reactivation of a developmentally silenced embryonic globin gene. Nat Commun 2021; 12:4439. [PMID: 34290235 PMCID: PMC8295333 DOI: 10.1038/s41467-021-24402-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 06/12/2021] [Indexed: 12/26/2022] Open
Abstract
The α- and β-globin loci harbor developmentally expressed genes, which are silenced throughout post-natal life. Reactivation of these genes may offer therapeutic approaches for the hemoglobinopathies, the most common single gene disorders. Here, we address mechanisms regulating the embryonically expressed α-like globin, termed ζ-globin. We show that in embryonic erythroid cells, the ζ-gene lies within a ~65 kb sub-TAD (topologically associating domain) of open, acetylated chromatin and interacts with the α-globin super-enhancer. By contrast, in adult erythroid cells, the ζ-gene is packaged within a small (~10 kb) sub-domain of hypoacetylated, facultative heterochromatin within the acetylated sub-TAD and that it no longer interacts with its enhancers. The ζ-gene can be partially re-activated by acetylation and inhibition of histone de-acetylases. In addition to suggesting therapies for severe α-thalassemia, these findings illustrate the general principles by which reactivation of developmental genes may rescue abnormalities arising from mutations in their adult paralogues.
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Affiliation(s)
- Andrew J King
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Duantida Songdej
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- Division of Hematology/Oncology, Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Damien J Downes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Robert A Beagrie
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Siyu Liu
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford, UK
| | - Megan Buckley
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Peng Hua
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Maria C Suciu
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | | | - Lars L P Hanssen
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Danuta Jeziorska
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Nigel Roberts
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Stephanie J Carpenter
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Helena Francis
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jelena Telenius
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Aude-Anais Olijnik
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jacqueline A Sharpe
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jacqueline Sloane-Stanley
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jennifer Eglinton
- National Haemoglobinopathy Reference Laboratory, Department of Haematology, Level 4, John Radcliffe Hospital, Oxford, UK
| | - Mira T Kassouf
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Stuart H Orkin
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Harvard Medical School and Howard Hughes Medical Institute, Boston, MA, USA
| | - Len A Pennacchio
- Functional Genomics Department, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Comparative Biochemistry Program, University of California, Berkeley, CA, USA
| | - James O J Davies
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jim R Hughes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Douglas R Higgs
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
| | - Christian Babbs
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
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Kumar S, Behera A, Saha P, Kumar Srivastava A. The role of Krüppel-like factor 8 in cancer biology: Current research and its clinical relevance. Biochem Pharmacol 2020; 183:114351. [PMID: 33253644 DOI: 10.1016/j.bcp.2020.114351] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 11/21/2020] [Accepted: 11/24/2020] [Indexed: 02/07/2023]
Abstract
Cancer is one of the leading causes of mortality worldwide, ranked second after heart disease. Despite recent advancements in diagnosis and treatment, there are still numerous problems associated with cancer progression, disease recurrence, and therapeutic resistance that are partially explored. Several studies have recently revealed that Krüppel-like factor 8 (KLF8) regulates transcription of genes linked with diverse biological processes, including proliferation, epithelial to mesenchymal transition (EMT), migration, invasion, and inflammation. KLF8 is expressed ubiquitously in mammalian cells, and its aberrant expression has been manifested with several cancer types. Earlier studies demonstrated the crucial role of KLF8 in DNA repair and resistance to apoptosis in numerous cancer types. Hence, studying the function of KLF8 from the perspective of cancer progression and therapy resistance would help develop a new therapeutic avenue. In this review, we summarize the clinical relevance of KLF8 expression in various malignancies, focusing on recent updates in EMT, cellular signaling, and cancer stem cells. We also address the contribution of KLF8 in development, DNA repair, chemoresistance, and its clinical utility as a predictive biomarker.
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Affiliation(s)
- Sanjay Kumar
- Division of Biology, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati 517507, AP, India.
| | - Abhijeet Behera
- Division of Biology, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati 517507, AP, India.
| | - Priyanka Saha
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, WB, India.
| | - Amit Kumar Srivastava
- Cancer Biology & Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, WB, India.
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7
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García-Niño WR, Zazueta C. New insights of Krüppel-like transcription factors in adipogenesis and the role of their regulatory neighbors. Life Sci 2020; 265:118763. [PMID: 33189819 DOI: 10.1016/j.lfs.2020.118763] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/06/2020] [Accepted: 11/11/2020] [Indexed: 12/16/2022]
Abstract
Obesity is a serious public health problem associated with predisposition to develop metabolic diseases. Over the past decade, several studies in vitro and in vivo have shown that the activity of Krüppel-like factors (KLFs) regulates adipogenesis, adipose tissue function and metabolism. Comprehension of both the origin and development of adipocytes and of adipose tissue could provide new insights into therapeutic strategies to contend against obesity and related metabolic diseases. This review focus on the transcriptional role that KLF family members play during adipocyte differentiation, describes their main interactions and the mechanisms involved in this fine-tuned developmental process. We also summarize new findings of the involvement of several effectors that modulate KLFs expression during adipogenesis, including growth factors, circadian clock proteins, interleukins, nuclear receptors, protein kinases and importantly, microRNAs. Thus, KLFs regulation by these factors and emerging molecules might constitute a potential therapeutic target for anti-obesity intervention.
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Affiliation(s)
- Wylly Ramsés García-Niño
- Department of Cardiovascular Biomedicine, National Institute of Cardiology "Ignacio Chávez", Mexico City 14080, Mexico.
| | - Cecilia Zazueta
- Department of Cardiovascular Biomedicine, National Institute of Cardiology "Ignacio Chávez", Mexico City 14080, Mexico.
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8
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Guo X, Plank-Bazinet J, Krivega I, Dale RK, Dean A. Embryonic erythropoiesis and hemoglobin switching require transcriptional repressor ETO2 to modulate chromatin organization. Nucleic Acids Res 2020; 48:10226-10240. [PMID: 32960220 DOI: 10.1093/nar/gkaa736] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/19/2020] [Accepted: 09/18/2020] [Indexed: 11/14/2022] Open
Abstract
The underlying mechanism of transcriptional co-repressor ETO2 during early erythropoiesis and hemoglobin switching is unclear. We find that absence of ETO2 in mice interferes with down-regulation of PU.1 and GATA2 in the fetal liver, impeding a key step required for commitment to erythroid maturation. In human β-globin transgenic Eto2 null mice and in human CD34+ erythroid progenitor cells with reduced ETO2, loss of ETO2 results in ineffective silencing of embryonic/fetal globin gene expression, impeding hemoglobin switching during erythroid differentiation. ETO2 occupancy genome-wide occurs virtually exclusively at LDB1-complex binding sites in enhancers and ETO2 loss leads to increased enhancer activity and expression of target genes. ETO2 recruits the NuRD nucleosome remodeling and deacetylation complex to regulate histone acetylation and nucleosome occupancy in the β-globin locus control region and γ-globin gene. Loss of ETO2 elevates LDB1, MED1 and Pol II in the locus and facilitates fetal γ-globin/LCR looping and γ-globin transcription. Absence of the ETO2 hydrophobic heptad repeat region impairs ETO2-NuRD interaction and function in antagonizing γ-globin/LCR looping. Our results reveal a pivotal role for ETO2 in erythropoiesis and globin gene switching through its repressive role in the LDB1 complex, affecting the transcription factor and epigenetic environment and ultimately restructuring chromatin organization.
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Affiliation(s)
- Xiang Guo
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 50 South Drive, Building 50, Room 3154, Bethesda, MD 20892, USA
| | - Jennifer Plank-Bazinet
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 50 South Drive, Building 50, Room 3154, Bethesda, MD 20892, USA
| | - Ivan Krivega
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 50 South Drive, Building 50, Room 3154, Bethesda, MD 20892, USA
| | - Ryan K Dale
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 50 South Drive, Building 50, Room 3154, Bethesda, MD 20892, USA
| | - Ann Dean
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 50 South Drive, Building 50, Room 3154, Bethesda, MD 20892, USA
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9
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Eosinophil function in adipose tissue is regulated by Krüppel-like factor 3 (KLF3). Nat Commun 2020; 11:2922. [PMID: 32523103 PMCID: PMC7286919 DOI: 10.1038/s41467-020-16758-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 05/20/2020] [Indexed: 01/01/2023] Open
Abstract
The conversion of white adipocytes to thermogenic beige adipocytes represents a potential mechanism to treat obesity and related metabolic disorders. However, the mechanisms involved in converting white to beige adipose tissue remain incompletely understood. Here we show profound beiging in a genetic mouse model lacking the transcriptional repressor Krüppel-like factor 3 (KLF3). Bone marrow transplants from these animals confer the beige phenotype on wild type recipients. Analysis of the cellular and molecular changes reveal an accumulation of eosinophils in adipose tissue. We examine the transcriptomic profile of adipose-resident eosinophils and posit that KLF3 regulates adipose tissue function via transcriptional control of secreted molecules linked to beiging. Furthermore, we provide evidence that eosinophils may directly act on adipocytes to drive beiging and highlight the critical role of these little-understood immune cells in thermogenesis. Immune cells are important regulators of adipose tissue function, including adaptive thermogenesis. Here the authors show that mice with Krüppel-like factor 3 (KLF3) deficiency in bone marrow-derived cells have increased adipose tissue beiging which may at least in part be due to altered eosinophil paracrine signaling.
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10
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Knights AJ, Yang L, Shah M, Norton LJ, Green GS, Stout ES, Vohralik EJ, Crossley M, Quinlan KGR. Krüppel-like factor 3 (KLF3) suppresses NF-κB-driven inflammation in mice. J Biol Chem 2020; 295:6080-6091. [PMID: 32213596 DOI: 10.1074/jbc.ra120.013114] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/18/2020] [Indexed: 12/14/2022] Open
Abstract
Bacterial products such as lipopolysaccharides (or endotoxin) cause systemic inflammation, resulting in a substantial global health burden. The onset, progression, and resolution of the inflammatory response to endotoxin are usually tightly controlled to avoid chronic inflammation. Members of the NF-κB family of transcription factors are key drivers of inflammation that activate sets of genes in response to inflammatory signals. Such responses are typically short-lived and can be suppressed by proteins that act post-translationally, such as the SOCS (suppressor of cytokine signaling) family. Less is known about direct transcriptional regulation of these responses, however. Here, using a combination of in vitro approaches and in vivo animal models, we show that endotoxin treatment induced expression of the well-characterized transcriptional repressor Krüppel-like factor 3 (KLF3), which, in turn, directly repressed the expression of the NF-κB family member RELA/p65. We also observed that KLF3-deficient mice were hypersensitive to endotoxin and exhibited elevated levels of circulating Ly6C+ monocytes and macrophage-derived inflammatory cytokines. These findings reveal that KLF3 is a fundamental suppressor that operates as a feedback inhibitor of RELA/p65 and may be important in facilitating the resolution of inflammation.
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Affiliation(s)
- Alexander J Knights
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Lu Yang
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Manan Shah
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Laura J Norton
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Gamran S Green
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Elizabeth S Stout
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Emily J Vohralik
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Merlin Crossley
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Kate G R Quinlan
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia.
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11
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Van Hese I, Goossens K, Vandaele L, Opsomer G. Invited review: MicroRNAs in bovine colostrum-Focus on their origin and potential health benefits for the calf. J Dairy Sci 2019; 103:1-15. [PMID: 31677833 DOI: 10.3168/jds.2019-16959] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 09/06/2019] [Indexed: 12/23/2022]
Abstract
Colostrum is the first milk produced by a cow after she gives birth. Compared with mature milk, it has a high concentration of immunoglobulin G. Calves are born without circulating antibodies, thus ingestion of colostrum is necessary to protect the calf against pathogens in the first challenging weeks of life. In addition to the life-saving supply of antibodies, colostrum contains minerals, vitamins, growth factors, and immune cells. Recently, microRNAs (miRNAs) were added to that list. MicroRNAs are short, non-coding RNA molecules that can regulate gene expression at the post-transcriptional level. They are thought to act as key regulators of diverse biological and developmental processes. Colostrum contains higher amounts of miRNAs than mature milk; immune- and development-related miRNAs are prominent. Their expression pattern in milk is likely to be influenced by maternal nutrition and environment. The fat content of the maternal diet appears to have a major effect on expression of miRNAs in milk and in the neonate. The immunological state of the mammary gland seems to affect miRNA expression as well. In cows diagnosed with subclinical mastitis, alterations in the expression of miRNAs in milk have been observed. It is believed that miRNAs in colostrum and milk are signaling molecules passed from mother to newborn. They are packaged in extracellular vesicles, which makes them resistant to the harsh conditions in the gastrointestinal tract. Therefore, they can reach the small intestine, where they are absorbed and transferred into the bloodstream. MicroRNAs are important for the development of the intestines. For example, miRNAs stimulate cell viability, proliferation, and stem cell activity of the intestinal epithelium. Furthermore, miRNAs seem to act as key players in the development of the complete immune system. They can, among other things, regulate B- and T-cell differentiation and affect interleukin production of macrophages. The abundance of miRNAs in colostrum and milk and the possibility for their absorption in the intestines of the neonate supports the hypothesis that these tiny molecules are important for the development of the newborn. The probable relation of diet to the expression of miRNAs by the mother creates a possible avenue to optimize expression of miRNAs and improve neonatal maturation.
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Affiliation(s)
- I Van Hese
- Animal Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Scheldeweg, Melle, 9090, Belgium; Department of Reproduction, Obstetrics and Herd Health Faculty of Veterinary Medicine, Ghent University, Salisburylaan, Merelbeke, 9820, Belgium.
| | - K Goossens
- Animal Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Scheldeweg, Melle, 9090, Belgium
| | - L Vandaele
- Animal Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Scheldeweg, Melle, 9090, Belgium
| | - G Opsomer
- Department of Reproduction, Obstetrics and Herd Health Faculty of Veterinary Medicine, Ghent University, Salisburylaan, Merelbeke, 9820, Belgium
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12
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Stratopoulos A, Kolliopoulou A, Karamperis K, John A, Kydonopoulou K, Esftathiou G, Sgourou A, Kourakli A, Vlachaki E, Chalkia P, Theodoridou S, Papadakis MN, Gerou S, Symeonidis A, Katsila T, Ali BR, Papachatzopoulou A, Patrinos GP. Genomic variants in members of the Krüppel-like factor gene family are associated with disease severity and hydroxyurea treatment efficacy in β-hemoglobinopathies patients. Pharmacogenomics 2019; 20:791-801. [PMID: 31393228 DOI: 10.2217/pgs-2019-0063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Aim: β-Type hemoglobinopathies are characterized by vast phenotypic diversity as far as disease severity is concerned, while differences have also been observed in hydroxyurea (HU) treatment efficacy. These differences are partly attributed to the residual expression of fetal hemoglobin (HbF) in adulthood. The Krüppel-like family of transcription factors (KLFs) are a set of zinc finger DNA-binding proteins which play a major role in HbF regulation. Here, we explored the possible association of variants in KLF gene family members with response to HU treatment efficacy and disease severity in β-hemoglobinopathies patients. Materials & methods: Six tag single nucleotide polymorphisms, located in four KLF genes, namely KLF3, KLF4, KLF9 and KLF10, were analyzed in 110 β-thalassemia major patients (TDT), 18 nontransfusion dependent β-thalassemia patients (NTDT), 82 sickle cell disease/β-thalassemia compound heterozygous patients and 85 healthy individuals as controls. Results: Our findings show that a KLF4 genomic variant (rs2236599) is associated with HU treatment efficacy in sickle cell disease/β-thalassemia compound heterozygous patients and two KLF10 genomic variants (rs980112, rs3191333) are associated with persistent HbF levels in NTDT patients. Conclusion: Our findings provide evidence that genomic variants located in KLF10 gene may be considered as potential prognostic biomarkers of β-thalassemia clinical severity and an additional variant in KLF4 gene as a pharmacogenomic biomarker, predicting response to HU treatment.
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Affiliation(s)
- Apostolos Stratopoulos
- University of Patras, School of Health Sciences, Department of Pharmacy, Laboratory of Pharmacogenomics & Individualized Therapy, Patras, Greece
| | - Alexandra Kolliopoulou
- University of Patras, School of Health Sciences, Department of Pharmacy, Laboratory of Pharmacogenomics & Individualized Therapy, Patras, Greece
| | - Kariofyllis Karamperis
- University of Patras, School of Health Sciences, Department of Pharmacy, Laboratory of Pharmacogenomics & Individualized Therapy, Patras, Greece
| | - Anne John
- United Arab Emirates University, College of Medicine & Health Sciences, Department of Pathology, Al-Ain, United Arab Emirates
| | | | | | - Argyro Sgourou
- School of Science & Technology, Biology Laboratory, Hellenic Open University, Patras, Greece
| | - Alexandra Kourakli
- Thalassemia & Hemoglobinopathies Unit, Hematology Division, Department of Internal Medicine, General University Hospital of Patras, Patras, Greece
| | - Efthimia Vlachaki
- Thalassemia Unit, "Hippocrateion" General Hospital of Thessaloniki, Thessaloniki, Greece
| | - Panagiota Chalkia
- Thalassemia & Sickle Cell Unit, AHEPA University General Hospital of Thessaloniki, Thessaloniki, Greece
| | - Stamatia Theodoridou
- Thalassemia Unit, "Hippocrateion" General Hospital of Thessaloniki, Thessaloniki, Greece
| | | | | | - Argiris Symeonidis
- Medical Faculty, Hematology Division, Department of Internal Medicine, University of Patras, Patras, Greece
| | - Theodora Katsila
- University of Patras, School of Health Sciences, Department of Pharmacy, Laboratory of Pharmacogenomics & Individualized Therapy, Patras, Greece
| | - Bassam R Ali
- United Arab Emirates University, College of Medicine & Health Sciences, Department of Pathology, Al-Ain, United Arab Emirates
| | | | - George P Patrinos
- University of Patras, School of Health Sciences, Department of Pharmacy, Laboratory of Pharmacogenomics & Individualized Therapy, Patras, Greece.,United Arab Emirates University, College of Medicine & Health Sciences, Department of Pathology, Al-Ain, United Arab Emirates.,United Arab Emirates University, Zayed Center of Health Sciences, Al-Ain, United Arab Emirates
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13
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Lam VC, Folkersen L, Aguilar OA, Lanier LL. KLF12 Regulates Mouse NK Cell Proliferation. THE JOURNAL OF IMMUNOLOGY 2019; 203:981-989. [PMID: 31300511 DOI: 10.4049/jimmunol.1900396] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 06/17/2019] [Indexed: 12/20/2022]
Abstract
NK cells are innate lymphocytes that play an integral role in tumor rejection and viral clearance. Unlike their other lymphocyte counterparts, NK cells have the unique ability to recognize and lyse target cells without prior exposure. However, there are no known NK cell-specific genes that are exclusively expressed by all NK cells. Therefore, identification of NK cell-specific genes would allow a better understanding of why NK cells are unique cytotoxic lymphocytes. From the Immunological Genome (ImmGen) Consortium studies, we identified kruppel-like factor 12 (Klf12), encoding a novel transcription factor, preferentially expressed in C57BL/6 mouse NK cells. KLF12 was dispensable for NK cell development, IFN-γ production, degranulation, and proliferation in Klf12 knockout mice. RNA-sequencing analysis revealed increased expression of Btg3, an antiproliferative gene, in KLF12-deficient NK cells compared with wild-type NK cells. Interestingly, competitive mixed bone marrow chimeric mice exhibited reduced development of KLF12-deficient NK cells, altered IFN-γ production and degranulation, and impairment of NK cell proliferation in vitro and in vivo in response to mouse CMV infection. KLF12-deficient NK cells from bone marrow chimeric mice also expressed higher levels of the IL-21R, which resulted in increased IL-21R signaling and correlated with greater inhibition of NK cell proliferation. Furthermore, IL-21 induced Btg3 expression, which correlated with arrested NK cell maturation and proliferation. In summary, we found that KLF12 regulates mouse NK cell proliferation potentially by regulating expression of Btg3 via IL-21.
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Affiliation(s)
- Viola C Lam
- Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco, CA 94143.,Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA 94143
| | - Lasse Folkersen
- Sankt Hans Hospital, Capital Region Hospitals, DK 2000 Copenhagen, Denmark; and
| | - Oscar A Aguilar
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA 94143.,Parker Institute for Cancer Immunotherapy, San Francisco, CA 94129
| | - Lewis L Lanier
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA 94143; .,Parker Institute for Cancer Immunotherapy, San Francisco, CA 94129
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14
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Salmon M, Spinosa M, Zehner ZE, Upchurch GR, Ailawadi G. Klf4, Klf2, and Zfp148 activate autophagy-related genes in smooth muscle cells during aortic aneurysm formation. Physiol Rep 2019; 7:e14058. [PMID: 31025534 PMCID: PMC6483937 DOI: 10.14814/phy2.14058] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/21/2019] [Accepted: 02/22/2019] [Indexed: 01/08/2023] Open
Abstract
Abdominal aortic aneurysms (AAAs) are a progressive dilation of the aorta that is characterized by an initial influx of inflammatory cells followed by a pro-inflammatory, migratory, proliferative, and eventually apoptotic smooth muscle cell phenotype. In recent years, the mechanisms related to the initial influx of inflammatory cells have become well-studied; the mechanisms related to chronic aneurysm formation, smooth muscle cell apoptosis and death are less well-characterized. Autophagy is a generally believed to be a protective cellular mechanism that functions to recycle defective proteins and cellular organelles to maintain cellular homeostasis. Our goal with the present study was to investigate the role of autophagy in smooth muscle cells during AAA formation. Levels of the autophagy factors, Beclin, and LC3 were elevated in human and mouse AAA tissue via both qPCR and immunohistochemical analysis. Confocal staining in human and mouse AAA tissue demonstrated Beclin and LC3 were present in smooth muscle cells during AAA formation. Treatment of smooth muscle cells with porcine pancreatic elastase or interleukin (IL)-1β activated autophagy-related genes in vitro while treatment with a siRNA to Kruppel-like transcription factor 4 (Klf4), Kruppel-like transcription factor 2 (Klf2) or Zinc-finger protein 148 (Zfp148) separately inhibited activation of autophagy genes. Chromatin immunoprecipitation assays demonstrated that Klf4, Klf2, and Zfp148 separately bind autophagy genes in smooth muscle cells following elastase treatment. These results demonstrate that autophagy is an important mechanism related to Klfs in smooth muscle cells during AAA formation.
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Affiliation(s)
- Morgan Salmon
- Department of SurgeryUniversity of Virginia School of MedicineCharlottesvilleVirginiaUSA
| | - Michael Spinosa
- Department of SurgeryUniversity of Virginia School of MedicineCharlottesvilleVirginiaUSA
| | - Zendra E. Zehner
- Department of BiochemistryVirginia Commonwealth University Medical CenterRichmondVirginiaUSA
| | | | - Gorav Ailawadi
- Department of SurgeryUniversity of Virginia School of MedicineCharlottesvilleVirginiaUSA
- The Robert M. Berne Cardiovascular Research CenterUniversity of Virginia School of MedicineCharlottesvilleVirginiaUSA
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15
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Wang R, Xu J, Xu J, Zhu W, Qiu T, Li J, Zhang M, Wang Q, Xu T, Guo R, Lu K, Yin Y, Gu Y, Zhu L, Huang P, Liu P, Liu L, De W, Shu Y. MiR-326/Sp1/KLF3: A novel regulatory axis in lung cancer progression. Cell Prolif 2019; 52:e12551. [PMID: 30485570 PMCID: PMC6495967 DOI: 10.1111/cpr.12551] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 09/27/2018] [Accepted: 10/17/2018] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVES To investigate the function and regulatory mechanism of Krüppel-like factor 3 (KLF3) in lung cancer. MATERIALS AND METHODS KLF3 expression was analysed by qRT-PCR and Western blot assays. The proliferation, migration, invasion, cycle and apoptosis were measured by CCK-8 and EdU, wound-healing and Transwell, and flow cytometry assays. The tumour growth was detected by nude mouse tumorigenesis assay. In addition, the interaction between KLF3 and Sp1 was accessed by luciferase reporter, EMSA and ChIP assay. JAK2, STAT3, PI3K and p-AKT levels were evaluated by Western blot and IHC assays. RESULTS The results indicated that KLF3 expression was elevated in lung cancer tissues. Knockdown of KLF3 inhibited lung cancer cell proliferation, migration and invasion, and induced cell cycle arrest and apoptosis. In addition, the downregulation of KLF3 suppressed tumour growth in vivo. KLF3 was transcriptionally activated by Sp1. miR-326 could bind to 3'UTR of Sp1 but not KLF3 and decreased the accumulation of Sp1, which further indirectly reduced KLF3 expression and inactivated JAK2/STAT3 and PI3K/AKT signaling pathways in vitro and in vivo. CONCLUSIONS Our data demonstrate that miR-326/Sp1/KLF3 regulatory axis is involved in the development of lung cancer, which hints the potential target for the further therapeutic strategy against lung cancer.
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Affiliation(s)
- Rong Wang
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Jiali Xu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Jing Xu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Wei Zhu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Tianzhu Qiu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Jun Li
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Meiling Zhang
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Qianqian Wang
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Tongpeng Xu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Renhua Guo
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Kaihua Lu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Yongmei Yin
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Yanhong Gu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Lingjun Zhu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Puwen Huang
- Department of OncologyLiyang people's Hospital of Jiangsu ProvinceLiyangChina
| | - Ping Liu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Lianke Liu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
| | - Wei De
- Department of Biochemistry and Molecular BiologyNanjing Medical UniversityNanjingChina
| | - Yongqian Shu
- Department of Oncologythe First Affiliated Hospital of Nanjing Medical University, Jiangsu Province HospitalNanjingChina
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16
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King AJ, Higgs DR. Potential new approaches to the management of the Hb Bart's hydrops fetalis syndrome: the most severe form of α-thalassemia. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2018; 2018:353-360. [PMID: 30504332 PMCID: PMC6246003 DOI: 10.1182/asheducation-2018.1.353] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The α-thalassemia trait, associated with deletions removing both α-globin genes from 1 chromosome (genotype ζ αα/ζ--), is common throughout Southeast Asia. Consequently, many pregnancies in couples of Southeast Asian origin carry a 1 in 4 risk of producing a fetus inheriting no functional α-globin genes (ζ--/ζ--), leading to hemoglobin (Hb) Bart's hydrops fetalis syndrome (BHFS). Expression of the embryonic α-globin genes (ζ-globin) is normally limited to the early stages of primitive erythropoiesis, and so when the ζ-globin genes are silenced, at ∼6 weeks of gestation, there should be no α-like globin chains to pair with the fetal γ-globin chains of Hb, which consequently form nonfunctional tetramers (γ4) known as Hb Bart's. When deletions leave the ζ-globin gene intact, a low level of ζ-globin gene expression continues in definitive erythroid cells, producing small amounts of Hb Portland (ζ2γ2), a functional form of Hb that allows the fetus to survive up to the second or third trimester. Untreated, all affected individuals die at these stages of development. Prevention is therefore of paramount importance. With improvements in early diagnosis, intrauterine transfusion, and advanced perinatal care, there are now a small number of individuals with BHFS who have survived, with variable outcomes. A deeper understanding of the mechanism underlying the switch from ζ- to α-globin expression could enable persistence or reactivation of embryonic globin synthesis in definitive cells, thereby providing new therapeutic options for such patients.
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Affiliation(s)
- Andrew J King
- Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom
| | - Douglas R Higgs
- Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom
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17
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Mukherjee D, Lu H, Yu L, He C, Lahiri SK, Li T, Zhao J. Krüppel-like factor 8 activates the transcription of C-X-C cytokine receptor type 4 to promote breast cancer cell invasion, transendothelial migration and metastasis. Oncotarget 2018; 7:23552-68. [PMID: 26993780 PMCID: PMC5029647 DOI: 10.18632/oncotarget.8083] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 02/25/2016] [Indexed: 02/04/2023] Open
Abstract
Krüppel-like factor 8 (KLF8) has been strongly implicated in breast cancer metastasis. However, the underlying mechanisms remain largely unknown. Here we report a novel signaling from KLF8 to C-X-C cytokine receptor type 4 (CXCR4) in breast cancer. Overexpression of KLF8 in MCF-10A cells induced CXCR4 expression at both mRNA and protein levels, as determined by quantitative real-time PCR and immunoblotting. This induction was well correlated with increased Boyden chamber migration, matrigel invasion and transendothelial migration (TEM) of the cells towards the ligand CXCL12. On the other hand, knockdown of KLF8 in MDA-MB-231 cells reduced CXCR4 expression associated with decreased cell migration, invasion and TEM towards CXCL12. Histological and database mining analyses of independent cohorts of patient tissue microarrays revealed a correlation of aberrant co-elevation of KLF8 and CXCR4 with metastatic potential. Promoter analysis indicated that KLF8 directly binds and activates the human CXCR4 gene promoter. Interestingly, a CXCR4-dependent activation of focal adhesion kinase (FAK), a known upregulator of KLF8, was highly induced by CXCL12 treatment in KLF8-overexpressing, but not KLF8 deficient cells. This activation of FAK in turn induced a further increase in KLF8 expression. Xenograft studies showed that overexpression of CXCR4, but not a dominant-negative mutant of it, in the MDA-MB-231 cells prevented the invasive growth of primary tumor and lung metastasis from inhibition by knockdown of KLF8. These results collectively suggest a critical role for a previously unidentified feed-forward signaling wheel made of KLF8, CXCR4 and FAK in promoting breast cancer metastasis and shed new light on potentially more effective anti-cancer strategies.
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Affiliation(s)
- Debarati Mukherjee
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Heng Lu
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Lin Yu
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Chunjiang He
- School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Satadru K Lahiri
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
| | - Tianshu Li
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA.,Current address: Cleveland Clinic, Cleveland, OH, USA
| | - Jihe Zhao
- Burnett School of Biomedical Sciences University of Central Florida College of Medicine, Orlando, FL, USA
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18
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Pollak NM, Hoffman M, Goldberg IJ, Drosatos K. Krüppel-like factors: Crippling and un-crippling metabolic pathways. JACC Basic Transl Sci 2018; 3:132-156. [PMID: 29876529 PMCID: PMC5985828 DOI: 10.1016/j.jacbts.2017.09.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/20/2022]
Abstract
Krüppel-like factors (KLFs) are DNA-binding transcriptional factors that regulate various pathways that control metabolism and other cellular mechanisms. Various KLF isoforms have been associated with cellular, organ or systemic metabolism. Altered expression or activation of KLFs has been linked to metabolic abnormalities, such as obesity and diabetes, as well as with heart failure. In this review article we summarize the metabolic functions of KLFs, as well as the networks of different KLF isoforms that jointly regulate metabolism in health and disease.
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Affiliation(s)
- Nina M. Pollak
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland, Australia
| | - Matthew Hoffman
- Metabolic Biology Laboratory, Center for Translational Medicine, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
| | - Ira J. Goldberg
- Division of Endocrinology, Diabetes and Metabolism, New York University School of Medicine, New York, New York
| | - Konstantinos Drosatos
- Metabolic Biology Laboratory, Center for Translational Medicine, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
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19
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Bialkowska AB, Yang VW, Mallipattu SK. Krüppel-like factors in mammalian stem cells and development. Development 2017; 144:737-754. [PMID: 28246209 DOI: 10.1242/dev.145441] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Krüppel-like factors (KLFs) are a family of zinc-finger transcription factors that are found in many species. Recent studies have shown that KLFs play a fundamental role in regulating diverse biological processes such as cell proliferation, differentiation, development and regeneration. Of note, several KLFs are also crucial for maintaining pluripotency and, hence, have been linked to reprogramming and regenerative medicine approaches. Here, we review the crucial functions of KLFs in mammalian embryogenesis, stem cell biology and regeneration, as revealed by studies of animal models. We also highlight how KLFs have been implicated in human diseases and outline potential avenues for future research.
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Affiliation(s)
- Agnieszka B Bialkowska
- Division of Gastroenterology, Department of Medicine, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA
| | - Vincent W Yang
- Division of Gastroenterology, Department of Medicine, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA.,Department of Physiology and Biophysics, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA
| | - Sandeep K Mallipattu
- Division of Nephrology, Department of Medicine, Stony Brook University School of Medicine, Stony Brook, NY 11794-8176, USA
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20
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Lin CY, Tsai MY, Liu YH, Lu YF, Chen YC, Lai YR, Liao HC, Lien HW, Yang CH, Huang CJ, Hwang SPL. Klf8 regulates left-right asymmetric patterning through modulation of Kupffer's vesicle morphogenesis and spaw expression. J Biomed Sci 2017; 24:45. [PMID: 28716076 PMCID: PMC5513281 DOI: 10.1186/s12929-017-0351-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 07/07/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although vertebrates are bilaterally symmetric organisms, their internal organs are distributed asymmetrically along a left-right axis. Disruption of left-right axis asymmetric patterning often occurs in human genetic disorders. In zebrafish embryos, Kupffer's vesicle, like the mouse node, breaks symmetry by inducing asymmetric expression of the Nodal-related gene, spaw, in the left lateral plate mesoderm (LPM). Spaw then stimulates transcription of itself and downstream genes, including lft1, lft2, and pitx2, specifically in the left side of the diencephalon, heart and LPM. This developmental step is essential to establish subsequent asymmetric organ positioning. In this study, we evaluated the role of krüppel-like factor 8 (klf8) in regulating left-right asymmetric patterning in zebrafish embryos. METHODS Zebrafish klf8 expression was disrupted by both morpholino antisense oligomer-mediated knockdown and a CRISPR-Cas9 system. Whole-mount in situ hybridization was conducted to evaluate gene expression patterns of Nodal signalling components and the positions of heart and visceral organs. Dorsal forerunner cell number was evaluated in Tg(sox17:gfp) embryos and the length and number of cilia in Kupffer's vesicle were analyzed by immunocytochemistry using an acetylated tubulin antibody. RESULTS Heart jogging, looping and visceral organ positioning were all defective in zebrafish klf8 morphants. At the 18-22 s stages, klf8 morphants showed reduced expression of genes encoding Nodal signalling components (spaw, lft1, lft2, and pitx2) in the left LPM, diencephalon, and heart. Co-injection of klf8 mRNA with klf8 morpholino partially rescued spaw expression. Furthermore, klf8 but not klf8△zf overexpressing embryos showed dysregulated bilateral expression of Nodal signalling components at late somite stages. At the 10s stage, klf8 morphants exhibited reductions in length and number of cilia in Kupffer's vesicle, while at 75% epiboly, fewer dorsal forerunner cells were observed. Interestingly, klf8 mutant embryos, generated by a CRISPR-Cas9 system, showed bilateral spaw expression in the LPM at late somite stages. This observation may be partly attributed to compensatory upregulation of klf12b, because klf12b knockdown reduced the percentage of klf8 mutants exhibiting bilateral spaw expression. CONCLUSIONS Our results demonstrate that zebrafish Klf8 regulates left-right asymmetric patterning by modulating both Kupffer's vesicle morphogenesis and spaw expression in the left LPM.
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Affiliation(s)
- Che-Yi Lin
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan.,Present address: Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Ming-Yuan Tsai
- Graduate Institute of Life Sciences, National Defence Medical Center, National Defence University, Neihu, Taipei, Taiwan.,Present address: Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Yu-Hsiu Liu
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Yu-Fen Lu
- Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, 11529, Taiwan
| | - Yi-Chung Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, 11529, Taiwan
| | - Yun-Ren Lai
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan
| | - Hsin-Chi Liao
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan
| | - Huang-Wei Lien
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | | | - Chang-Jen Huang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Sheng-Ping L Hwang
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan. .,Department of Life Science, National Taiwan University, Taipei, Taiwan. .,Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, 11529, Taiwan.
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21
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Ilsley MD, Gillinder KR, Magor GW, Huang S, Bailey TL, Crossley M, Perkins AC. Krüppel-like factors compete for promoters and enhancers to fine-tune transcription. Nucleic Acids Res 2017; 45:6572-6588. [PMID: 28541545 PMCID: PMC5499887 DOI: 10.1093/nar/gkx441] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 05/22/2017] [Indexed: 12/16/2022] Open
Abstract
Krüppel-like factors (KLFs) are a family of 17 transcription factors characterized by a conserved DNA-binding domain of three zinc fingers and a variable N-terminal domain responsible for recruiting cofactors. KLFs have diverse functions in stem cell biology, embryo patterning, and tissue homoeostasis. KLF1 and related family members function as transcriptional activators via recruitment of co-activators such as EP300, whereas KLF3 and related members act as transcriptional repressors via recruitment of C-terminal Binding Proteins. KLF1 directly activates the Klf3 gene via an erythroid-specific promoter. Herein, we show KLF1 and KLF3 bind common as well as unique sites within the erythroid cell genome by ChIP-seq. We show KLF3 can displace KLF1 from key erythroid gene promoters and enhancers in vivo. Using 4sU RNA labelling and RNA-seq, we show this competition results in reciprocal transcriptional outputs for >50 important genes. Furthermore, Klf3-/- mice displayed exaggerated recovery from anemic stress and persistent cell cycling consistent with a role for KLF3 in dampening KLF1-driven proliferation. We suggest this study provides a paradigm for how KLFs work in incoherent feed-forward loops or networks to fine-tune transcription and thereby control diverse biological processes such as cell proliferation.
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Affiliation(s)
- Melissa D. Ilsley
- Mater Research Institute, Translational Research Institute, University of Queensland, Brisbane 4102, Australia
- School of Biomedical Sciences, University of Queensland, Brisbane 4072, Australia
| | - Kevin R. Gillinder
- Mater Research Institute, Translational Research Institute, University of Queensland, Brisbane 4102, Australia
| | - Graham W. Magor
- Mater Research Institute, Translational Research Institute, University of Queensland, Brisbane 4102, Australia
| | - Stephen Huang
- Mater Research Institute, Translational Research Institute, University of Queensland, Brisbane 4102, Australia
- School of Biomedical Sciences, University of Queensland, Brisbane 4072, Australia
| | | | | | - Andrew C. Perkins
- Mater Research Institute, Translational Research Institute, University of Queensland, Brisbane 4102, Australia
- School of Biomedical Sciences, University of Queensland, Brisbane 4072, Australia
- The Princess Alexandra Hospital, Brisbane 4102, Australia
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22
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Norton LJ, Hallal S, Stout ES, Funnell APW, Pearson RCM, Crossley M, Quinlan KGR. Direct competition between DNA binding factors highlights the role of Krüppel-like Factor 1 in the erythroid/megakaryocyte switch. Sci Rep 2017; 7:3137. [PMID: 28600522 PMCID: PMC5466599 DOI: 10.1038/s41598-017-03289-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 04/26/2017] [Indexed: 11/15/2022] Open
Abstract
The Krüppel-like factor (KLF) family of transcription factors play critical roles in haematopoiesis. KLF1, the founding member of the family, has been implicated in the control of both erythropoiesis and megakaryopoiesis. Here we describe a novel system using an artificial dominant negative isoform of KLF1 to investigate the role of KLF1 in the erythroid/megakaryocytic switch in vivo. We developed murine cell lines stably overexpressing a GST-KLF1 DNA binding domain fusion protein (GST-KLF1 DBD), as well as lines expressing GST only as a control. Interestingly, overexpression of GST-KLF1 DBD led to an overall reduction in erythroid features and an increase in megakaryocytic features indicative of a reduced function of endogenous KLF1. We simultaneously compared in vivo DNA occupancy of both endogenous KLF1 and GST-KLF1 DBD by ChIP qPCR. Here we found that GST-KLF1 DBD physically displaces endogenous KLF1 at a number of loci, providing novel in vivo evidence of direct competition between DNA binding proteins. These results highlight the role of KLF1 in the erythroid/megakaryocyte switch and suggest that direct competition between transcription factors with similar consensus sequences is an important mechanism in transcriptional regulation.
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Affiliation(s)
- Laura J Norton
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Samantha Hallal
- School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia
| | - Elizabeth S Stout
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Alister P W Funnell
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.,School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia
| | - Richard C M Pearson
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.,School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia
| | - Merlin Crossley
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.,School of Molecular Bioscience, University of Sydney, Sydney, NSW, 2006, Australia
| | - Kate G R Quinlan
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.
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23
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Mak KS, Burdach J, Norton LJ, Pearson RCM, Crossley M, Funnell APW. Erratum to: Repression of chimeric transcripts emanating from endogenous retrotransposons by a sequence-specific transcription factor. Genome Biol 2016; 17:119. [PMID: 27259285 PMCID: PMC4891914 DOI: 10.1186/s13059-016-0977-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 05/05/2016] [Indexed: 11/10/2022] Open
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24
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Krüppeling erythropoiesis: an unexpected broad spectrum of human red blood cell disorders due to KLF1 variants. Blood 2016; 127:1856-62. [PMID: 26903544 DOI: 10.1182/blood-2016-01-694331] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 02/09/2016] [Indexed: 02/06/2023] Open
Abstract
Until recently our approach to analyzing human genetic diseases has been to accurately phenotype patients and sequence the genes known to be associated with those phenotypes; for example, in thalassemia, the globin loci are analyzed. Sequencing has become increasingly accessible, and thus a larger panel of genes can be analyzed and whole exome and/or whole genome sequencing can be used when no variants are found in the candidate genes. By using such approaches in patients with unexplained anemias, we have discovered that a broad range of hitherto unrelated human red cell disorders are caused by variants in KLF1, a master regulator of erythropoiesis, which were previously considered to be extremely rare causes of human genetic disease.
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25
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Simmen RCM, Heard ME, Simmen AM, Montales MTM, Marji M, Scanlon S, Pabona JMP. The Krüppel-like factors in female reproductive system pathologies. J Mol Endocrinol 2015; 54:R89-R101. [PMID: 25654975 PMCID: PMC4369192 DOI: 10.1530/jme-14-0310] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Female reproductive tract pathologies arise largely from dysregulation of estrogen and progesterone receptor signaling, leading to aberrant cell proliferation, survival, and differentiation. The signaling pathways orchestrated by these nuclear receptors are complex, require the participation of many nuclear proteins serving as key binding partners or targets, and involve a range of paracrine and autocrine regulatory circuits. The members of the Krüppel-like factor (KLF) family of transcription factors are ubiquitously expressed in reproductive tissues and have been increasingly implicated as critical co-regulators and integrators of steroid hormone actions. Herein, we explore the involvement of KLF family members in uterine pathology, describe their currently known molecular mechanisms, and discuss their potential as targets for therapeutic intervention.
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Affiliation(s)
- Rosalia C M Simmen
- Department of Physiology and BiophysicsUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USADepartment of Obstetrics and GynecologyUniversity of Michigan Health System, Ann Arbor, Michigan 48109, USADepartment of Internal MedicineHarlem Hospital Center, Columbia University Medical Center, New York, New York 10037, USA
| | - Melissa E Heard
- Department of Physiology and BiophysicsUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USADepartment of Obstetrics and GynecologyUniversity of Michigan Health System, Ann Arbor, Michigan 48109, USADepartment of Internal MedicineHarlem Hospital Center, Columbia University Medical Center, New York, New York 10037, USA
| | - Angela M Simmen
- Department of Physiology and BiophysicsUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USADepartment of Obstetrics and GynecologyUniversity of Michigan Health System, Ann Arbor, Michigan 48109, USADepartment of Internal MedicineHarlem Hospital Center, Columbia University Medical Center, New York, New York 10037, USA
| | - Maria Theresa M Montales
- Department of Physiology and BiophysicsUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USADepartment of Obstetrics and GynecologyUniversity of Michigan Health System, Ann Arbor, Michigan 48109, USADepartment of Internal MedicineHarlem Hospital Center, Columbia University Medical Center, New York, New York 10037, USA
| | - Meera Marji
- Department of Physiology and BiophysicsUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USADepartment of Obstetrics and GynecologyUniversity of Michigan Health System, Ann Arbor, Michigan 48109, USADepartment of Internal MedicineHarlem Hospital Center, Columbia University Medical Center, New York, New York 10037, USA
| | - Samantha Scanlon
- Department of Physiology and BiophysicsUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USADepartment of Obstetrics and GynecologyUniversity of Michigan Health System, Ann Arbor, Michigan 48109, USADepartment of Internal MedicineHarlem Hospital Center, Columbia University Medical Center, New York, New York 10037, USA
| | - John Mark P Pabona
- Department of Physiology and BiophysicsUniversity of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USADepartment of Obstetrics and GynecologyUniversity of Michigan Health System, Ann Arbor, Michigan 48109, USADepartment of Internal MedicineHarlem Hospital Center, Columbia University Medical Center, New York, New York 10037, USA
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26
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KLF1-null neonates display hydrops fetalis and a deranged erythroid transcriptome. Blood 2015; 125:2405-17. [PMID: 25724378 DOI: 10.1182/blood-2014-08-590968] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 02/21/2015] [Indexed: 12/14/2022] Open
Abstract
We describe a case of severe neonatal anemia with kernicterus caused by compound heterozygosity for null mutations in KLF1, each inherited from asymptomatic parents. One of the mutations is novel. This is the first described case of a KLF1-null human. The phenotype of severe nonspherocytic hemolytic anemia, jaundice, hepatosplenomegaly, and marked erythroblastosis is more severe than that present in congenital dyserythropoietic anemia type IV as a result of dominant mutations in the second zinc-finger of KLF1. There was a very high level of HbF expression into childhood (>70%), consistent with a key role for KLF1 in human hemoglobin switching. We performed RNA-seq on circulating erythroblasts and found that human KLF1 acts like mouse Klf1 to coordinate expression of many genes required to build a red cell including those encoding globins, cytoskeletal components, AHSP, heme synthesis enzymes, cell-cycle regulators, and blood group antigens. We identify novel KLF1 target genes including KIF23 and KIF11 which are required for proper cytokinesis. We also identify new roles for KLF1 in autophagy, global transcriptional control, and RNA splicing. We suggest loss of KLF1 should be considered in otherwise unexplained cases of severe neonatal NSHA or hydrops fetalis.
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27
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Dewi V, Kwok A, Lee S, Lee MM, Tan YM, Nicholas HR, Isono KI, Wienert B, Mak KS, Knights AJ, Quinlan KGR, Cordwell SJ, Funnell APW, Pearson RCM, Crossley M. Phosphorylation of Krüppel-like factor 3 (KLF3/BKLF) and C-terminal binding protein 2 (CtBP2) by homeodomain-interacting protein kinase 2 (HIPK2) modulates KLF3 DNA binding and activity. J Biol Chem 2015; 290:8591-605. [PMID: 25659434 DOI: 10.1074/jbc.m115.638338] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Krüppel-like factor 3 (KLF3/BKLF), a member of the Krüppel-like factor (KLF) family of transcription factors, is a widely expressed transcriptional repressor with diverse biological roles. Although there is considerable understanding of the molecular mechanisms that allow KLF3 to silence the activity of its target genes, less is known about the signal transduction pathways and post-translational modifications that modulate KLF3 activity in response to physiological stimuli. We observed that KLF3 is modified in a range of different tissues and found that the serine/threonine kinase homeodomain-interacting protein kinase 2 (HIPK2) can both bind and phosphorylate KLF3. Mass spectrometry identified serine 249 as the primary phosphorylation site. Mutation of this site reduces the ability of KLF3 to bind DNA and repress transcription. Furthermore, we also determined that HIPK2 can phosphorylate the KLF3 co-repressor C-terminal binding protein 2 (CtBP2) at serine 428. Finally, we found that phosphorylation of KLF3 and CtBP2 by HIPK2 strengthens the interaction between these two factors and increases transcriptional repression by KLF3. Taken together, our results indicate that HIPK2 potentiates the activity of KLF3.
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Affiliation(s)
- Vitri Dewi
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Alister Kwok
- the School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, 2006, Australia, and
| | - Stella Lee
- the School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, 2006, Australia, and
| | - Ming Min Lee
- the School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, 2006, Australia, and
| | - Yee Mun Tan
- the School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, 2006, Australia, and
| | - Hannah R Nicholas
- the School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, 2006, Australia, and
| | - Kyo-ichi Isono
- the RIKEN Research Center for Allergy and Immunology, Tsurumi-ku, Yokohama City, Kanagawa 230-0045, Japan
| | - Beeke Wienert
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Ka Sin Mak
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Alexander J Knights
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Kate G R Quinlan
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Stuart J Cordwell
- the School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, 2006, Australia, and
| | - Alister P W Funnell
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Richard C M Pearson
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Merlin Crossley
- From the School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia, the School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, 2006, Australia, and
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28
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Zhang Y, Hao J, Zheng Y, Jing D, Shen Y, Wang J, Zhao Z. Role of Krüppel-like factors in cancer stem cells. J Physiol Biochem 2015; 71:155-64. [PMID: 25616500 DOI: 10.1007/s13105-015-0381-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 01/13/2015] [Indexed: 02/05/2023]
Abstract
Cancer stem cells (CSCs), or cancer cells with stem cell properties, are a rare population of tumor bulk and are recognized to be responsible for cancer recurrence, drug resistance, and metastasis. However, the molecular mechanisms of how to regulate the differentiation and self-renewing of CSCs are poorly understood. Krüppel-like factors (KLFs) are essential DNA-binding transcriptional regulators with diverse functions in various cellular processes, including differentiation, proliferation, inflammation, migration, and pluripotency. Recent progress has highlighted the significance of KLFs in tumor progression and CSCs. The regulatory functions of KLFs in the development of cancer and CSCs have become a burgeoning area of intense research. In this review, we summarize the current understanding and progress of the transcriptional regulation of KLFs in CSCs and discuss the functional implications of targeting CSCs by KLFs for cancer therapeutics.
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Affiliation(s)
- Yueling Zhang
- Department of Orthodontics, State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, West China School of Stomatology, Sichuan University, #14, 3rd section of Renmin South Road, Chengdu, 610041, China
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29
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Tsai MY, Lu YF, Liu YH, Lien HW, Huang CJ, Wu JL, Hwang SPL. Modulation of p53 and met expression by Krüppel-like factor 8 regulates zebrafish cerebellar development. Dev Neurobiol 2014; 75:908-26. [PMID: 25528982 DOI: 10.1002/dneu.22258] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 12/04/2014] [Accepted: 12/15/2014] [Indexed: 12/20/2022]
Abstract
Krüppel-like factor 8 (Klf8) is a zinc-finger transcription factor implicated in cell proliferation, and cancer cell survival and invasion; however, little is known about its role in normal embryonic development. Here, we show that Klf8 is required for normal cerebellar development in zebrafish embryos. Morpholino knockdown of klf8 resulted in abnormal cerebellar primordium morphology and the induction of p53 in the brain region at 24 hours post-fertilization (hpf). Both p53-dependent reduction of cell proliferation and augmentation of apoptosis were observed in the cerebellar anlage of 24 hpf-klf8 morphants. In klf8 morphants, expression of ptf1a in the ventricular zone was decreased from 48 to 72 hpf; on the other hand, expression of atohla in the upper rhombic lip was unaffected. Consistent with this finding, Purkinje cell development was perturbed and granule cell number was reduced in 72 hpf-klf8 morphants; co-injection of p53 MO(sp) or klf8 mRNA substantially rescued development of cerebellar Purkinje cells in klf8 morphants. Hepatocyte growth factor/Met signaling is known to regulate cerebellar development in zebrafish and mouse. We observed decreased met expression in the tectum and rhombomere 1 of 24 hpf-klf8 morphants, which was largely rescued by co-injection with klf8 mRNA. Moreover, co-injection of met mRNA substantially rescued formation of Purkinje cells in klf8 morphants at 72 hpf. Together, these results demonstrate that Klf8 modulates expression of p53 and met to maintain ptf1a-expressing neuronal progenitors, which are required for the appropriate development of cerebellar Purkinje and granule cells in zebrafish embryos.
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Affiliation(s)
- Ming-Yuan Tsai
- Graduate Institute of Life Sciences, National Defense Medical Center, Neihu, Taipei, Taiwan, 114, Republic of China
| | - Yu-Fen Lu
- Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, Taiwan, 115, Republic of China
| | - Yu-Hsiu Liu
- Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, Taiwan, 115, Republic of China.,Institute of Zoology, National Taiwan University, Taipei, Taiwan, 10617, Republic of China
| | - Huang-Wei Lien
- Institute of Biological Chemistry, Academia Sinica, Nankang, Taipei, Taiwan, 115, Republic of China
| | - Chang-Jen Huang
- Graduate Institute of Life Sciences, National Defense Medical Center, Neihu, Taipei, Taiwan, 114, Republic of China.,Institute of Biological Chemistry, Academia Sinica, Nankang, Taipei, Taiwan, 115, Republic of China
| | - Jen-Leih Wu
- Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, Taiwan, 115, Republic of China
| | - Sheng-Ping L Hwang
- Graduate Institute of Life Sciences, National Defense Medical Center, Neihu, Taipei, Taiwan, 114, Republic of China.,Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, Taiwan, 115, Republic of China
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30
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Vinjamur DS, Wade KJ, Mohamad SF, Haar JL, Sawyer ST, Lloyd JA. Krüppel-like transcription factors KLF1 and KLF2 have unique and coordinate roles in regulating embryonic erythroid precursor maturation. Haematologica 2014; 99:1565-73. [PMID: 25150253 DOI: 10.3324/haematol.2014.104943] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The Krüppel-like transcription factors KLF1 and KLF2 are essential for embryonic erythropoiesis. They can partially compensate for each other during mouse development, and coordinately regulate numerous erythroid genes, including the β-like globins. Simultaneous ablation of KLF1 and KLF2 results in earlier embryonic lethality and severe anemia. In this study, we determine that this anemia is caused by a paucity of blood cells, and exacerbated by diminished β-like globin gene expression. The anemia phenotype is dose-dependent, and, interestingly, can be ameliorated by a single copy of the KLF2, but not the KLF1 gene. The roles of KLF1 and KLF2 in maintaining normal peripheral blood cell numbers and globin mRNA amounts are erythroid cell-specific. Mechanistic studies led to the discovery that KLF2 has an essential function in erythroid precursor maintenance. KLF1 can partially compensate for KLF2 in this role, but is uniquely crucial for erythroid precursor proliferation through its regulation of G1- to S-phase cell cycle transition. A more drastic impairment of primitive erythroid colony formation from embryonic progenitor cells occurs with simultaneous loss of KLF1 and KLF2 than with loss of a single factor. KLF1 and KLF2 coordinately regulate several proliferation-associated genes, including Foxm1. Differential expression of FoxM1, in particular, correlates with the observed KLF1 and KLF2 gene dosage effects on anemia. Furthermore, KLF1 binds to the FoxM1 gene promoter in blood cells. Thus KLF1 and KLF2 coordinately regulate embryonic erythroid precursor maturation through the regulation of multiple homeostasis-associated genes, and KLF2 has a novel and essential role in this process.
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Affiliation(s)
- Divya S Vinjamur
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, USA
| | - Kristen J Wade
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, USA
| | - Safa F Mohamad
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, USA
| | - Jack L Haar
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
| | - Stephen T Sawyer
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Joyce A Lloyd
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, USA Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA
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31
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Fetal globin gene repressors as drug targets for molecular therapies to treat the β-globinopathies. Mol Cell Biol 2014; 34:3560-9. [PMID: 25022757 DOI: 10.1128/mcb.00714-14] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The human β-globin locus is comprised of embryonic, fetal, and adult globin genes that are expressed in a developmental stage-specific manner. Mutations in the globin locus give rise to the β-globinopathies, β-thalassemia and sickle cell disease, which begin to manifest symptoms around the time of birth. Although the fetal globin genes are autonomously silenced in adult-stage erythroid cells, mutations lying both within and outside the locus lead to natural variations in the level of fetal globin gene expression, and some of these significantly ameliorate the clinical symptoms of the β-globinopathies. Multiple reports have now identified several transcription factors that are involved in fetal globin gene repression in definitive (adult)-stage erythroid cells (the TR2/TR4 heterodimer, MYB, KLFs, BCL11A, and SOX6). To carry out their repression functions, chromatin-modifying enzymes (such as DNA methyltransferase, histone deacetylases, and lysine-specific histone demethylase 1) are additionally involved as a consequence of forming large macromolecular complexes with the DNA-binding subunits of these cellular machines. This review focuses on the molecular mechanisms underlying fetal globin gene silencing and possible near-future molecularly targeted therapies for treating the β-globinopathies.
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32
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Funnell APW, Vernimmen D, Lim WF, Mak KS, Wienert B, Martyn GE, Artuz CM, Burdach J, Quinlan KGR, Higgs DR, Whitelaw E, Pearson RCM, Crossley M. Differential regulation of the α-globin locus by Krüppel-like Factor 3 in erythroid and non-erythroid cells. BMC Mol Biol 2014; 15:8. [PMID: 24885809 PMCID: PMC4033687 DOI: 10.1186/1471-2199-15-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 05/06/2014] [Indexed: 12/17/2022] Open
Abstract
Background Krüppel-like Factor 3 (KLF3) is a broadly expressed zinc-finger transcriptional repressor with diverse biological roles. During erythropoiesis, KLF3 acts as a feedback repressor of a set of genes that are activated by Krüppel-like Factor 1 (KLF1). Noting that KLF1 binds α-globin gene regulatory sequences during erythroid maturation, we sought to determine whether KLF3 also interacts with the α-globin locus to regulate transcription. Results We found that expression of a human transgenic α-globin reporter gene is markedly up-regulated in fetal and adult erythroid cells of Klf3−/− mice. Inspection of the mouse and human α-globin promoters revealed a number of canonical KLF-binding sites, and indeed, KLF3 was shown to bind to these regions both in vitro and in vivo. Despite these observations, we did not detect an increase in endogenous murine α-globin expression in Klf3−/− erythroid tissue. However, examination of murine embryonic fibroblasts lacking KLF3 revealed significant de-repression of α-globin gene expression. This suggests that KLF3 may contribute to the silencing of the α-globin locus in non-erythroid tissue. Moreover, ChIP-Seq analysis of murine fibroblasts demonstrated that across the locus, KLF3 does not occupy the promoter regions of the α-globin genes in these cells, but rather, binds to upstream, DNase hypersensitive regulatory regions. Conclusions These findings reveal that the occupancy profile of KLF3 at the α-globin locus differs in erythroid and non-erythroid cells. In erythroid cells, KLF3 primarily binds to the promoters of the adult α-globin genes, but appears dispensable for normal transcriptional regulation. In non-erythroid cells, KLF3 distinctly binds to the HS-12 and HS-26 elements and plays a non-redundant, albeit modest, role in the silencing of α-globin expression.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Merlin Crossley
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
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33
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Mak KS, Burdach J, Norton LJ, Pearson RCM, Crossley M, Funnell APW. Repression of chimeric transcripts emanating from endogenous retrotransposons by a sequence-specific transcription factor. Genome Biol 2014; 15:R58. [PMID: 24946810 PMCID: PMC4056533 DOI: 10.1186/gb-2014-15-4-r58] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 04/30/2014] [Indexed: 11/10/2022] Open
Abstract
Background Retroviral elements are pervasively transcribed and dynamically regulated during development. While multiple histone- and DNA-modifying enzymes have broadly been associated with their global silencing, little is known about how the many diverse retroviral families are each selectively recognized. Results Here we show that the zinc finger protein Krüppel-like Factor 3 (KLF3) specifically silences transcription from the ORR1A0 long terminal repeat in murine fetal and adult erythroid cells. In the absence of KLF3, we detect widespread transcription from ORR1A0 elements driven by the master erythroid regulator KLF1. In several instances these aberrant transcripts are spliced to downstream genic exons. One such chimeric transcript produces a novel, dominant negative isoform of PU.1 that can induce erythroid differentiation. Conclusions We propose that KLF3 ensures the integrity of the murine erythroid transcriptome through the selective repression of a particular retroelement and is likely one of multiple sequence-specific factors that cooperate to achieve global silencing.
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34
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Mutations in Kruppel-like factor 1 cause transfusion-dependent hemolytic anemia and persistence of embryonic globin gene expression. Blood 2014; 123:1586-95. [PMID: 24443441 DOI: 10.1182/blood-2013-09-526087] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this study, we report on 8 compound heterozygotes for mutations in the key erythroid transcription factor Krüppel-like factor 1 in patients who presented with severe, transfusion-dependent hemolytic anemia. In most cases, the red cells were hypochromic and microcytic, consistent with abnormalities in hemoglobin synthesis. In addition, in many cases, the red cells resembled those seen in patients with membrane defects or enzymopathies, known as chronic nonspherocytic hemolytic anemia (CNSHA). Analysis of RNA and protein in primary erythroid cells from these individuals provided evidence of abnormal globin synthesis, with persistent expression of fetal hemoglobin and, most remarkably, expression of large quantities of embryonic globins in postnatal life. The red cell membranes were abnormal, most notably expressing reduced amounts of CD44 and, consequently, manifesting the rare In(Lu) blood group. Finally, all tested patients showed abnormally low levels of the red cell enzyme pyruvate kinase, a known cause of CNSHA. These patients define a new type of severe, transfusion-dependent CNSHA caused by mutations in a trans-acting factor (Krüppel-like factor 1) and reveal an important pathway regulating embryonic globin gene expression in adult humans.
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35
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Roosjen M, McColl B, Kao B, Gearing LJ, Blewitt ME, Vadolas J. Transcriptional regulators Myb and BCL11A interplay with DNA methyltransferase 1 in developmental silencing of embryonic and fetal β-like globin genes. FASEB J 2013; 28:1610-20. [PMID: 24371119 DOI: 10.1096/fj.13-242669] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The clinical symptoms of hemoglobin disorders such as β-thalassemia and sickle cell anemia are significantly ameliorated by the persistent expression of γ-globin after birth. This knowledge has driven the discovery of important regulators that silence γ-globin postnatally. Improved understanding of the γ- to β-globin switching mechanism holds the key to devising targeted therapies for β-hemoglobinopathies. To further investigate this mechanism, we used the murine erythroleukemic (MEL) cell line containing an intact 183-kb human β-globin locus, in which the (G)γ- and β-globin genes are replaced by DsRed and eGFP fluorescent reporters, respectively. Following RNA interference (RNAi)-mediated knockdown of two key transcriptional regulators, Myb and BCL11A, we observed a derepression of γ-globin, measured by DsRed fluorescence and qRT-PCR (P<0.001). Interestingly, double knockdown of Myb and DNA methyltransferase 1 (DNMT1) resulted in a robust induction of ε-globin, (up to 20% of total β-like globin species) compared to single knockdowns (P<0.001). Conversely, double knockdowns of BCL11A and DNMT1 enhanced γ-globin expression (up to 90% of total β-like globin species) compared to single knockdowns (P<0.001). Moreover, following RNAi treatment, expression of human β-like globin genes mirrored the expression levels of their endogenous murine counterparts. These results demonstrate that Myb and BCL11A cooperate with DNMT1 to achieve developmental repression of embryonic and fetal β-like globin genes in the adult erythroid environment.
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Affiliation(s)
- Mark Roosjen
- 1Cell and Gene Therapy Group, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Rd., Parkville, VIC 3052, Australia.
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Burdach J, Funnell APW, Mak KS, Artuz CM, Wienert B, Lim WF, Tan LY, Pearson RCM, Crossley M. Regions outside the DNA-binding domain are critical for proper in vivo specificity of an archetypal zinc finger transcription factor. Nucleic Acids Res 2013; 42:276-89. [PMID: 24106088 PMCID: PMC3874204 DOI: 10.1093/nar/gkt895] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Transcription factors (TFs) are often regarded as being composed of a DNA-binding domain (DBD) and a functional domain. The two domains are considered separable and autonomous, with the DBD directing the factor to its target genes and the functional domain imparting transcriptional regulation. We examined an archetypal zinc finger (ZF) TF, Krüppel-like factor 3 with an N-terminal domain that binds the corepressor CtBP and a DBD composed of three ZFs at its C-terminus. We established a system to compare the genomic occupancy profile of wild-type Krüppel-like factor 3 with two mutants affecting the N-terminal functional domain: a mutant unable to contact the cofactor CtBP and a mutant lacking the entire N-terminal domain, but retaining the ZFs intact. Chromatin immunoprecipitation followed by sequencing was used to assess binding across the genome in murine embryonic fibroblasts. Unexpectedly, we observe that mutations in the N-terminal domain generally reduced binding, but there were also instances where binding was retained or even increased. These results provide a clear demonstration that the correct localization of TFs to their target genes is not solely dependent on their DNA-contact domains. This informs our understanding of how TFs operate and is of relevance to the design of artificial ZF proteins.
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Affiliation(s)
- Jon Burdach
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, NSW 2052, Australia and School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
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