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Liu Q, Tang J, Chen Z, Wei L, Chen J, Xie Z. Polyunsaturated fatty acids ameliorate renal stone-induced renal tubular damage via miR-93-5p/Pknox1 axis. Nutrition 2023; 105:111863. [PMID: 36356379 DOI: 10.1016/j.nut.2022.111863] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 08/28/2022] [Accepted: 09/28/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVES Polyunsaturated fatty acids (PUFAs) can decrease the risk of calcium oxalate stone formation, which accounts for 80% of all renal stones. This study aimed to investigate the protective mechanisms of PUFAs against renal stones. METHODS Urine samples of patients with renal stones and biopsy tissue samples from patients with nephrocalcinosis were tested for miR-93-5p expression. A renal stone mouse model was established with intraperitoneal injection of glyoxylic acid, during which mice were treated with PUFAs and/or an miR-93-5p inhibitor adenovirus. Periodic acid-Schiff staining, terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling staining, oil red O staining, triacylglycerol assay, and colorimetry testing were performed to assess glycogen deposition, apoptosis, lipid accumulation, blood urea nitrogen, and serum creatinine levels, respectively. Renal proximal tubular epithelial cells (human kidney 2 [HK-2]) were subjected to gain- and loss-of-function assays before calcium-oxalate monohydrate (COM) induction and PUFA treatment. Cell counting kit 8, flow cytometry, and lactate dehydrogenase activity assays were used to examine cell viability, apoptosis, and damage. A luciferase reporter gene assay verified the interaction between miR-93-5p and Pknox1, and miR-93-5p and Pknox1 levels were assessed using a reverse transcription-quantitative polymerase chain reaction and Western blot analysis. RESULTS miR-93-5p was downregulated in clinical samples with renal stones and negatively targeted Pknox1. PUFAs increased miR-93-5p expression and reduced apoptosis, glycogen deposition, and lipid accumulation in mice with renal stones, which were annulled by miR-93-5p downregulation. PUFAs increased proliferation and diminished apoptosis, lipid accumulation, and lactate dehydrogenase activity in COM-induced HK-2 cells, which were negated by miR-93-5p inhibition. Pknox1 overexpression reversed the effect of miR-93-5p upregulation on COM-induced HK-2 cells. CONCLUSIONS PUFAs repressed renal stone-induced renal tubular damage via the miR-93-5p/Pknox1 axis.
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Affiliation(s)
- Qin Liu
- Department of Nephrology, The First Affiliated Hospital of University of South China, Hengyang Medical School, University of South China, Hengyang, Hunan, P. R. China
| | - Jun Tang
- Department of Emergency, The First Affiliated Hospital of University of South China, Hengyang Medical School, University of South China, Hengyang, Hunan, P. R. China
| | - Zhong Chen
- Department of Nuclear Medicine, The First Affiliated Hospital of University of South China, Hengyang Medical School, University of South China, Hengyang, Hunan, P. R. China
| | - Lanji Wei
- Health Management Center, The Affiliated Nanhua Hospital of University of South China, Hengyang Medical School, University of South China, Hengyang, Hunan, P. R. China
| | - Jianying Chen
- Department of Rheumatology and Immunology, Hunan Provincial People's Hospital (Mawangdui Hospital), Changsha, Hunan, China
| | - Zhijuan Xie
- Department of Nephrology, The First Affiliated Hospital of University of South China, Hengyang Medical School, University of South China, Hengyang, Hunan, P. R. China.
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Cimmino I, Prisco F, Orso S, Agognon AL, Liguoro P, De Biase D, Doti N, Ruvo M, Paciello O, Beguinot F, Formisano P, Oriente F. Interleukin 6 reduces vascular smooth muscle cell apoptosis via Prep1 and is associated with aging. FASEB J 2021; 35:e21989. [PMID: 34679197 DOI: 10.1096/fj.202100943r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 09/08/2021] [Accepted: 09/29/2021] [Indexed: 11/11/2022]
Abstract
Aging exacerbates neointimal formation by reducing apoptosis of vascular smooth muscle cells (VSMCs) and induces inflammation within vascular wall. Prep1 is a homeodomain transcription factor which stimulates the expression of proinflammatory cytokines in aortic endothelial cell models and plays a primary role in the regulation of apoptosis. In this study, we have investigated the role of Prep1 in aorta of Prep1 hypomorphic heterozygous mice (Prep1i/+ ) and in VSMCs, and its correlation with aging. Histological analysis from Prep1i/+ aortas revealed a 25% reduction in medial smooth muscle cell density compared to WT animals. This result paralleled higher apoptosis, caspase 3, caspase 9 and p53 levels in Prep1i/+ mice and lower Bcl-xL. Prep1 overexpression in VSMCs decreased apoptosis by 25% and caspase 3 and caspase 9 expression by 40% and 37%. In parallel, Bcl-xL inhibition by BH3I-1 and p53 induction by etoposide reverted the antiapoptotic effect of Prep1. Experiments performed in aorta from 18 months old WT mice showed a significant increase in Prep1, p16INK4 , p21Waf1 and interleukin 6 (IL-6) compared to youngest animals. Similar results have been observed in H2 O2 -induced senescent VSMCs. Interestingly, the synthetic Prep1 inhibitory peptide Prep1 (54-72) reduced the antiapoptotic effects mediated by IL-6, particularly in senescent VSMCs. These results indicate that IL-6-Prep1 signaling reduces apoptosis, by modulating Bcl-xL and p53 both in murine aorta and in VSMCs. In addition, age-dependent increase in IL-6 and Prep1 in senescent VSMCs and in old mice may be involved in the aging-related vascular dysfunction.
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Affiliation(s)
- Ilaria Cimmino
- Department of Translational Medicine, Federico II University of Naples and URT "Genomic of Diabetes" of Institute of Experimental Endocrinology and Oncology, National Council of Research (CNR), Naples, Italy
| | - Francesco Prisco
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Naples, Italy
| | - Sonia Orso
- Department of Translational Medicine, Federico II University of Naples and URT "Genomic of Diabetes" of Institute of Experimental Endocrinology and Oncology, National Council of Research (CNR), Naples, Italy
| | - Ayewa L Agognon
- Department of Translational Medicine, Federico II University of Naples and URT "Genomic of Diabetes" of Institute of Experimental Endocrinology and Oncology, National Council of Research (CNR), Naples, Italy
| | - Pasquale Liguoro
- Department of Translational Medicine, Federico II University of Naples and URT "Genomic of Diabetes" of Institute of Experimental Endocrinology and Oncology, National Council of Research (CNR), Naples, Italy
| | - Davide De Biase
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Naples, Italy
| | - Nunzianna Doti
- Institute of Biostructure and Bioimaging, National Research Council and Interuniversity Research Centre on Bioactive Peptides Naples, Naples, Italy
| | - Menotti Ruvo
- Institute of Biostructure and Bioimaging, National Research Council and Interuniversity Research Centre on Bioactive Peptides Naples, Naples, Italy
| | - Orlando Paciello
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Naples, Italy
| | - Francesco Beguinot
- Department of Translational Medicine, Federico II University of Naples and URT "Genomic of Diabetes" of Institute of Experimental Endocrinology and Oncology, National Council of Research (CNR), Naples, Italy
| | - Pietro Formisano
- Department of Translational Medicine, Federico II University of Naples and URT "Genomic of Diabetes" of Institute of Experimental Endocrinology and Oncology, National Council of Research (CNR), Naples, Italy
| | - Francesco Oriente
- Department of Translational Medicine, Federico II University of Naples and URT "Genomic of Diabetes" of Institute of Experimental Endocrinology and Oncology, National Council of Research (CNR), Naples, Italy
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Miyake Y, Obana M, Nakae T, Yamamoto A, Tanaka S, Maeda M, Okada Y, Fujio Y. PKNOX2 regulates myofibroblast functions and tubular cell survival during kidney fibrosis. Biochem Biophys Res Commun 2021; 571:88-95. [PMID: 34311199 DOI: 10.1016/j.bbrc.2021.07.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/15/2021] [Accepted: 07/19/2021] [Indexed: 12/01/2022]
Abstract
The number of patients with chronic kidney disease (CKD) is increasing worldwide. When kidneys are exposed to severe injury, tubular cell death occurs and kidney fibrosis progresses by activating fibroblasts and myofibroblasts (referred to as (myo)fibroblasts), leading to CKD; however, the pathological and molecular mechanisms underlying CKD, including kidney fibrosis, remain obscure. In the present study, we focused on a transcription factor PBX/Knotted Homeobox 2 (PKNOX2) in kidney fibrosis. The transcript and protein expression of PKNOX2 was upregulated in fibrotic kidneys after unilateral ureteral obstruction (UUO). Importantly, immunofluorescence microscopic analysis revealed that the number of PKNOX2-expressing myofibroblasts was increased, whereas the expression of PKNOX2 was decreased in proximal tubular epithelial cells after UUO. In (myo)fibroblasts, PKNOX2 was induced by TGF-β1. Knockdown of PKNOX2 using shRNA lentiviral system reduced the viability of (myo)fibroblasts either in the presence or absence of TGF-β1, accompanied by increased apoptosis. Moreover, PKNOX2 knockdown decreased TGF-β1-induced migration of myofibroblasts and differentiation of fibroblasts into myofibroblasts. Significantly, knockdown of PKNOX2 also decreased the viability and increased apoptosis of tubular epithelial cells. Collectively, PKNOX2 regulates the function of (myo)fibroblasts and the viability of proximal tubular epithelial cells in progression of kidney fibrosis.
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Affiliation(s)
- Yoshiaki Miyake
- Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Japan
| | - Masanori Obana
- Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Japan; Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, Japan; Radioisotope Research Center, Institute for Radiation Sciences, Osaka University, Japan; Global Center for Medical Engineering and Informatics (MEI), Osaka University, Japan.
| | - Takafumi Nakae
- Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Japan
| | - Ayaha Yamamoto
- Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Japan
| | - Shota Tanaka
- Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Japan
| | - Makiko Maeda
- Laboratory of Clinical Pharmacology and Therapeutics, Graduate School of Pharmaceutical Sciences, Osaka University, Japan; Medical Center for Translational Research, Department of Medical Innovation, Osaka University Hospital, Japan
| | - Yoshiaki Okada
- Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Japan
| | - Yasushi Fujio
- Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Japan; Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, Japan
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Izzo A, Mollo N, Nitti M, Paladino S, Calì G, Genesio R, Bonfiglio F, Cicatiello R, Barbato M, Sarnataro V, Conti A, Nitsch L. Mitochondrial dysfunction in down syndrome: molecular mechanisms and therapeutic targets. Mol Med 2018; 24:2. [PMID: 30134785 PMCID: PMC6016872 DOI: 10.1186/s10020-018-0004-y] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 02/13/2018] [Indexed: 01/11/2023] Open
Abstract
Trisomy of chromosome 21 (TS21) is the most common autosomal aneuploidy compatible with postnatal survival with a prevalence of 1 in 700 newborns. Its phenotype is highly complex with constant features, such as mental retardation, dysmorphic traits and hypotonia, and variable features including heart defects, susceptibility to Alzheimer’s disease (AD), type 2 diabetes, obesity and immune disorders. Overexpression of genes on chromosome-21 (Hsa21) is responsible for the pathogenesis of Down syndrome (DS) phenotypic features either in a direct or in an indirect manner since many Hsa21 genes can affect the expression of other genes mapping to different chromosomes. Many of these genes are involved in mitochondrial function and energy conversion, and play a central role in the mitochondrial dysfunction and chronic oxidative stress, consistently observed in DS subjects. Recent studies highlight the deep interconnections between mitochondrial dysfunction and DS phenotype. In this short review we first provide a basic overview of mitochondrial phenotype in DS cells and tissues. We then discuss how specific Hsa21 genes may be involved in determining the disruption of mitochondrial DS phenotype and biogenesis. Finally we briefly focus on drugs that affect mitochondrial function and mitochondrial network suggesting possible therapeutic approaches to improve and/or prevent some aspects of the DS phenotype.
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Affiliation(s)
- Antonella Izzo
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Nunzia Mollo
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Maria Nitti
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Simona Paladino
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Gaetano Calì
- Institute of Experimental Endocrinology and Oncology, National Research Council, 80131, Naples, Italy
| | - Rita Genesio
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Ferdinando Bonfiglio
- Department of Biosciences and Nutrition, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Rita Cicatiello
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Maria Barbato
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Viviana Sarnataro
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
| | - Anna Conti
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy.
| | - Lucio Nitsch
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via Pansini 5, 80131, Naples, Italy
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Stagni F, Giacomini A, Emili M, Guidi S, Bartesaghi R. Neurogenesis impairment: An early developmental defect in Down syndrome. Free Radic Biol Med 2018; 114:15-32. [PMID: 28756311 DOI: 10.1016/j.freeradbiomed.2017.07.026] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 07/24/2017] [Accepted: 07/25/2017] [Indexed: 02/06/2023]
Abstract
Down syndrome (DS) is characterized by brain hypotrophy and intellectual disability starting from early life stages. Accumulating evidence shows that the phenotypic features of the DS brain can be traced back to the fetal period since the DS brain exhibits proliferation potency reduction starting from the critical time window of fetal neurogenesis. This defect is worsened by the fact that neural progenitor cells exhibit reduced acquisition of a neuronal phenotype and an increase in the acquisition of an astrocytic phenotype. Consequently, the DS brain has fewer neurons in comparison with the typical brain. Although apoptotic cell death may be increased in DS, this does not seem to be the major cause of brain hypocellularity. Evidence obtained in brains of individuals with DS, DS-derived induced pluripotent stem cells (iPSCs), and DS mouse models has provided some insight into the mechanisms underlying the developmental defects due to the trisomic condition. Although many triplicated genes may be involved, in the light of the studies reviewed here, DYRK1A, APP, RCAN1 and OLIG1/2 appear to be particularly important determinants of many neurodevelopmental alterations that characterize DS because their triplication affects both the proliferation and fate of neural precursor cells as well as apoptotic cell death. Based on the evidence reviewed here, pathways downstream to these genes may represent strategic targets, for the design of possible interventions.
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Affiliation(s)
- Fiorenza Stagni
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Andrea Giacomini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Marco Emili
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Sandra Guidi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
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Prep1 prevents premature adipogenesis of mesenchymal progenitors. Sci Rep 2017; 7:15573. [PMID: 29138456 PMCID: PMC5686065 DOI: 10.1038/s41598-017-15828-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 10/31/2017] [Indexed: 11/09/2022] Open
Abstract
Transcriptional regulators are crucial in adipocyte differentiation. We now show that the homeodomain-containing transcription factor Prep1 is a repressor of adipogenic differentiation since its down-regulation (DR) in both ex vivo bone marrow-derived mesenchymal stromal cells (MSC) and in vitro 3T3-L1 preadipocytes significantly increases their adipogenic differentiation ability. Prep1 acts at a stage preceding the activation of the differentiation machinery because its DR makes cells more prone to adipogenic differentiation even in the absence of the adipogenic inducers. Prep1 DR expands the DNA binding landscape of C/EBPβ (CCAAT enhancer binding protein β) without affecting its expression or activation. The data indicate that Prep1 normally acts by restricting DNA binding of transcription factors to adipogenic enhancers, in particular C/EBPβ.
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7
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Blasi F, Bruckmann C, Penkov D, Dardaei L. A tale of TALE, PREP1, PBX1, and MEIS1: Interconnections and competition in cancer. Bioessays 2017; 39. [DOI: 10.1002/bies.201600245] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Francesco Blasi
- IFOM, Foundation FIRC (Italian Foundation for Cancer Research) Institute of Molecular Oncology; Milan Italy
| | - Chiara Bruckmann
- IFOM, Foundation FIRC (Italian Foundation for Cancer Research) Institute of Molecular Oncology; Milan Italy
| | - Dmitry Penkov
- IFOM, Foundation FIRC (Italian Foundation for Cancer Research) Institute of Molecular Oncology; Milan Italy
| | - Leila Dardaei
- Massachusetts General Hospital Cancer Center; Charlestown MA USA
- Department of Medicine; Harvard Medical School; Boston MA USA
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Cabochette P, Vega-Lopez G, Bitard J, Parain K, Chemouny R, Masson C, Borday C, Hedderich M, Henningfeld KA, Locker M, Bronchain O, Perron M. YAP controls retinal stem cell DNA replication timing and genomic stability. eLife 2015; 4:e08488. [PMID: 26393999 PMCID: PMC4578106 DOI: 10.7554/elife.08488] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Accepted: 08/20/2015] [Indexed: 12/27/2022] Open
Abstract
The adult frog retina retains a reservoir of active neural stem cells that contribute to continuous eye growth throughout life. We found that Yap, a downstream effector of the Hippo pathway, is specifically expressed in these stem cells. Yap knock-down leads to an accelerated S-phase and an abnormal progression of DNA replication, a phenotype likely mediated by upregulation of c-Myc. This is associated with an increased occurrence of DNA damage and eventually p53-p21 pathway-mediated cell death. Finally, we identified PKNOX1, a transcription factor involved in the maintenance of genomic stability, as a functional and physical interactant of YAP. Altogether, we propose that YAP is required in adult retinal stem cells to regulate the temporal firing of replication origins and quality control of replicated DNA. Our data reinforce the view that specific mechanisms dedicated to S-phase control are at work in stem cells to protect them from genomic instability. DOI:http://dx.doi.org/10.7554/eLife.08488.001 In animals, stem cells divide to produce the new cells needed to grow and renew tissues and organs. Understanding the biology of these cells is of the utmost importance for developing new treatments for a wide range of human diseases, including neurodegenerative diseases and cancer. Before a stem cell divides, it copies its DNA and the two sets of genetic instructions are then separated so that the two daughter cells both have a complete set. This process needs to be as accurate as possible because any errors would result in incorrect genetic information being passed on to the daughter cells. Stem cells in the light-sensitive part of the eye—called the retina—divide to produce the cells that detect light and relay visual information to the brain. In many animals, these stem cells stop dividing soon after birth and the retina stops growing. However, the stem cells in frogs and fish continue to divide throughout the life of the animal, which enables the eye to keep on growing. A protein called YAP regulates the growth of organs in animal embryos, but it is not clear what role this protein plays in stem cells, particularly after birth. To address this question, Cabochette et al. studied YAP in the retina of frog tadpoles. The experiments show that YAP is produced in the stem cells of the retina after birth and is required for the retina to continue to grow. Cabochette et al. used tools called ‘photo-cleavable Morpholinos’ to alter the production of YAP in adult stem cells. The cells that produced less YAP copied their DNA more quickly and more of their DNA became damaged, which eventually led to the death of these cells. Further experiments revealed that YAP interacts with a protein called PKNOX1, which is involved in maintaining the integrity of DNA. Cabochette et al.'s findings provide the first insights into how YAP works in the stem cells of the retina and demonstrate that it plays a crucial role in regulating when DNA is copied. A future challenge is to find out whether YAP plays a similar role in the stem cells of other organs in adult animals. DOI:http://dx.doi.org/10.7554/eLife.08488.002
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Affiliation(s)
- Pauline Cabochette
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Guillermo Vega-Lopez
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Juliette Bitard
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Karine Parain
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Institute of Developmental Biochemistry, University of Goettingen, Goettingen, Germany
| | - Romain Chemouny
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Christel Masson
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Caroline Borday
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Marie Hedderich
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Institute of Developmental Biochemistry, University of Goettingen, Goettingen, Germany
| | - Kristine A Henningfeld
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Institute of Developmental Biochemistry, University of Goettingen, Goettingen, Germany
| | - Morgane Locker
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Odile Bronchain
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
| | - Muriel Perron
- Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Orsay, France
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Yoshioka K, Oda A, Notsu C, Ohtsuka T, Kawai Y, Suzuki S, Nakamura T, Mabuchi Y, Matsuzaki Y, Goitsuka R. Loss of the Homeodomain Transcription Factor Prep1 Perturbs Adult Hematopoiesis in the Bone Marrow. PLoS One 2015; 10:e0136107. [PMID: 26285139 PMCID: PMC4540428 DOI: 10.1371/journal.pone.0136107] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 07/29/2015] [Indexed: 11/18/2022] Open
Abstract
Prep1, a TALE-family homeodomain transcription factor, has been demonstrated to play a critical role in embryonic hematopoiesis, as its insufficiency caused late embryonic lethality associated with defective hematopoiesis and angiogenesis. In the present study, we generated hematopoietic- and endothelial cell-specific Prep1-deficient mice and demonstrated that expression of Prep1 in the hematopoietic cell compartment is not essential for either embryonic or adult hematopoiesis, although its absence causes significant hematopoietic abnormalities in the adult bone marrow. Loss of Prep1 promotes cell cycling of hematopoietic stem/progenitor cells (HSPC), leading to the expansion of the HSPC pool. Prep1 deficiency also results in the accumulation of lineage-committed progenitors, increased monocyte/macrophage differentiation and arrested erythroid maturation. Maturation of T cells and B cells is also perturbed in Prep-deficient mice. These findings provide novel insight into the pleiotropic roles of Prep1 in adult hematopoiesis that were unrecognized in previous studies using germline Prep1 hypomorphic mice.
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Affiliation(s)
- Kentaro Yoshioka
- Division of Development and Aging, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Akihisa Oda
- Division of Development and Aging, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Chihiro Notsu
- Division of Development and Aging, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Takafumi Ohtsuka
- Division of Development and Aging, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Yasuhiro Kawai
- Division of Development and Aging, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
| | - Sadafumi Suzuki
- Department of Physiology, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Takuro Nakamura
- Division of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, Koto-ku, Tokyo, Japan
| | - Yo Mabuchi
- Department of Biochemistry and Biophysics, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Yumi Matsuzaki
- Department of Cancer Biology, Faculty of Medicine, Shimane University, Izumo-shi, Shimane, Japan
| | - Ryo Goitsuka
- Division of Development and Aging, Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, Japan
- * E-mail:
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Prep1 and Meis1 competition for Pbx1 binding regulates protein stability and tumorigenesis. Proc Natl Acad Sci U S A 2014; 111:E896-905. [PMID: 24578510 DOI: 10.1073/pnas.1321200111] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Pbx-regulating protein-1 (Prep1) is a tumor suppressor, whereas myeloid ecotropic viral integration site-1 (Meis1) is an oncogene. We show that, to perform these activities in mouse embryonic fibroblasts, both proteins competitively heterodimerize with pre-B-cell leukemia homeobox-1 (Pbx1). Meis1 alone transforms Prep1-deficient fibroblasts, whereas Prep1 overexpression inhibits Meis1 tumorigenicity. Pbx1 can, therefore, alternatively act as an oncogene or tumor suppressor. Prep1 posttranslationally controls the level of Meis1, decreasing its stability by sequestering Pbx1. The different levels of Meis1 and the presence of Prep1 are followed at the transcriptional level by the induction of specific transcriptional signatures. The decrease of Meis1 prevents Meis1 interaction with Ddx3x and Ddx5, which are essential for Meis1 tumorigenesis, and modifies the growth-promoting DNA binding landscape of Meis1 to the growth-controlling landscape of Prep1. Hence, the key feature of Prep1 tumor-inhibiting activity is the control of Meis1 stability.
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12
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Mourskaia AA, Amir E, Dong Z, Tiedemann K, Cory S, Omeroglu A, Bertos N, Ouellet V, Clemons M, Scheffer GL, Park M, Hallett M, Komarova SV, Siegel PM. ABCC5 supports osteoclast formation and promotes breast cancer metastasis to bone. Breast Cancer Res 2012; 14:R149. [PMID: 23174366 PMCID: PMC4053136 DOI: 10.1186/bcr3361] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Accepted: 11/12/2012] [Indexed: 12/12/2022] Open
Abstract
Introduction Bone is the most common site of breast cancer metastasis, and complications associated with bone metastases can lead to a significantly decreased patient quality of life. Thus, it is essential to gain a better understanding of the molecular mechanisms that underlie the emergence and growth of breast cancer skeletal metastases. Methods To search for novel molecular mediators that influence breast cancer bone metastasis, we generated gene-expression profiles from laser-capture microdissected trephine biopsies of both breast cancer bone metastases and independent primary breast tumors that metastasized to bone. Bioinformatics analysis identified genes that are differentially expressed in breast cancer bone metastases compared with primary, bone-metastatic breast tumors. Results ABCC5, an ATP-dependent transporter, was found to be overexpressed in breast cancer osseous metastases relative to primary breast tumors. In addition, ABCC5 was significantly upregulated in human and mouse breast cancer cell lines with high bone-metastatic potential. Stable knockdown of ABCC5 substantially reduced bone metastatic burden and osteolytic bone destruction in mice. The decrease in osteolysis was further associated with diminished osteoclast numbers in vivo. Finally, conditioned media from breast cancer cells with reduced ABCC5 expression failed to induce in vitro osteoclastogenesis to the same extent as conditioned media from breast cancer cells expressing ABCC5. Conclusions Our data suggest that ABCC5 functions as a mediator of breast cancer skeletal metastasis. ABCC5 expression in breast cancer cells is important for efficient osteoclast-mediated bone resorption. Hence, ABCC5 may be a potential therapeutic target for breast cancer bone metastasis.
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Rosales-Aviña JA, Torres-Flores J, Aguilar-Lemarroy A, Gurrola-Díaz C, Hernández-Flores G, Ortiz-Lazareno PC, Lerma-Díaz JM, de Celis R, González-Ramella Ó, Barrera-Chaires E, Bravo-Cuellar A, Jave-Suárez LF. MEIS1, PREP1, and PBX4 are differentially expressed in acute lymphoblastic leukemia: association of MEIS1 expression with higher proliferation and chemotherapy resistance. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2011; 30:112. [PMID: 22185299 PMCID: PMC3259065 DOI: 10.1186/1756-9966-30-112] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 12/20/2011] [Indexed: 01/27/2023]
Abstract
Background The Three-amino acid-loop-extension (TALE) superfamily of homeodomain-containing transcription factors have been implicated in normal hematopoiesis and in leukemogenesis and are important survival, differentiation, and apoptosis pathway modulators. In this work, we determined the expression levels of TALE genes in leukemic-derived cell lines, in blood samples of patients with Acute lymphoblastic leukemia (ALL), and in the blood samples of healthy donors. Results Here we show increased expression of MEIS1, MEIS2, and PREP1 genes in leukemia-derived cell lines compared with blood normal cells. High levels of MEIS1 and PREP1, and low levels of PBX4 expression were also founded in samples of patients with ALL. Importantly, silencing of MEIS1 decreases the proliferation of leukemia-derived cells but increases their survival after etoposide treatment. Etoposide-induced apoptosis induces down-regulation of MEIS1 expression or PREP1 up-regulation in chemotherapy-resistant cells. Conclusions Our results indicate that up-regulation of MEIS1 is important for sustaining proliferation of leukemic cells and that down-regulation of MEIS1 or up-regulation of PREP1 and PBX genes could be implicated in the modulation of the cellular response to chemotherapeutic-induced apoptosis.
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Affiliation(s)
- Judith A Rosales-Aviña
- División de Inmunología, Centro de Investigación Biomédica de Occidente - IMSS, Sierra Mojada No. 800, CP 44340, Guadalajara, Jalisco, Mexico
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Abstract
The three-amino-acid loop extension (TALE) class homeodomain proteins MEIS1 and PKNOX1 (PREP1) share the ability to interact with PBX and HOX family members and bind similar DNA sequences but appear to play opposing roles in tumor development. Elevated levels of MEIS1 accelerate development of HOX- and MLL-induced leukemias, and this pro-tumorigenic property has been associated with transcriptional activity of MEIS1. In contrast, reduction of PKNOX1 levels has been linked with cancer development despite the absence of an identifiable transactivating domain. In this report, we show that a chimeric protein generated by fusion of the MEIS1 C-terminal region encompassing the transactivating domain with the full-length PKNOX1 (PKNOX1-MC) acquired the ability to accelerate the onset of Hoxa9-induced leukemia in the mouse bone marrow transduction/transplantation model. Gene expression profiling of primary bone marrow cells transduced with Hoxa9 plus Meis1, or Hoxa9 plus Pknox1-MC revealed perturbations in overlapping functional gene subsets implicated in DNA packaging, chromosome organization, and in cell cycle regulation. Together, results presented in this report suggest that the C-terminal domain of MEIS1 confers to PKNOX1 an ectopic transactivating function that promotes leukemogenesis by regulating expression of genes involved in chromatin accessibility and cell cycle progression.
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Homeodomain transcription factor and tumor suppressor Prep1 is required to maintain genomic stability. Proc Natl Acad Sci U S A 2011; 108:E314-22. [PMID: 21715654 DOI: 10.1073/pnas.1105216108] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Prep1 is a homeodomain transcription factor that is essential in embryonic development and functions in the adult as a tumor suppressor. We show here that Prep1 is involved in maintaining genomic stability and preventing neoplastic transformation. Hypomorphic homozygous Prep1(i/i) fetal liver cells and mouse embryonic fibroblasts (MEFs) exhibit increased basal DNA damage and normal DNA damage response after γ-irradiation compared with WT. Cytogenetic analysis shows the presence of numerous chromosomal aberrations and aneuploidy in very early-passage Prep1(i/i) MEFs. In human fibroblasts, acute Prep1 down-regulation by siRNA induces DNA damage response, like in Prep1(i/i) MEFs, together with an increase in heterochromatin-associated modifications: rapid increase of histone methylation and decreased transcription of satellite DNA. Ectopic expression of Prep1 rescues DNA damage and heterochromatin methylation. Inhibition of Suv39 activity blocks the chromatin but not the DNA damage phenotype. Finally, Prep1 deficiency facilitates cell immortalization, escape from oncogene-induced senescence, and H-Ras(V12)-dependent transformation. Importantly, the latter can be partially rescued by restoration of Prep1 level. The results show that the tumor suppressor role of Prep1 is associated with the maintenance of genomic stability.
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Spencer C, Montalvo J, McLaughlin SR, Bryan BA. Small molecule inhibition of cytoskeletal dynamics in melanoma tumors results in altered transcriptional expression patterns of key genes involved in tumor initiation and progression. Cancer Genomics Proteomics 2011; 8:77-85. [PMID: 21471517 PMCID: PMC3209963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
BACKGROUND Rho kinase signaling plays an important role in the oncogenic process largely through its regulation of F-actin dynamics, and inhibition of this pathway results in reduction in tumor volume and metastasis across a number of tumor types. While the cytoskeletal-regulatory role of Rho kinase has been a topic of in-depth study, the mechanisms linking Rho kinase to altered gene expression are largely unknown. MATERIALS AND METHODS Global gene expression analysis was performed on melanoma tumors treated with sham or the small molecule inhibitor Y27632. RESULTS Inhibition of Rho kinase activity in melanoma tumors results in a statistically significant change in gene transcription of 94 genes, many of which are critically involved in tumor initiation and progression. CONCLUSION In addition to regulating tumorigenesis through modulation of the phosphoproteome, Rho kinase signaling also contributes to the regulation of the tumor transcriptome.
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Affiliation(s)
- Carrie Spencer
- Ghosh Science and Technology Center, Department of Biology, Worcester State University, Worcester, MA 01602 USA
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Characterization of the regulatory region of the zebrafish Prep1.1 gene: analogies to the promoter of the human PREP1. PLoS One 2010; 5:e15047. [PMID: 21203543 PMCID: PMC3008670 DOI: 10.1371/journal.pone.0015047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 10/25/2010] [Indexed: 01/29/2023] Open
Abstract
Prep1 is a developmentally essential TALE class homeodomain transcription factor. In zebrafish and mouse, Prep1 is already ubiquitously expressed at the earliest stages of development, with important tissue-specific peculiarities. The Prep1 gene in mouse is developmentally essential and has haploinsufficient tumor suppressor activity [1]. We have determined the human Prep1 transcription start site (TSS) by primer extension analysis and identified, within 20 bp, the transcription start region (TSR) of the zebrafish Prep1.1 promoter. The functions of the zebrafish 5′ upstream sequences were analyzed both by transient transfections in Hela Cells and by injection in zebrafish embryos. This analysis revealed a complex promoter with regulatory sequences extending up to −1.8, possibly −5.0 Kb, responsible for tissue specific expression. Moreover, the first intron contains a conserved tissue-specific enhancer both in zebrafish and in human cells. Finally, a two nucleotides mutation of an EGR-1 site, conserved in all species including human and zebrafish and located at a short distance from the TSS, destroyed the promoter activity of the −5.0 Kb promoter. A transgenic fish expressing GFP under the −1.8 Kb zebrafish promoter/enhancer co-expressed GFP and endogenous Prep1.1 during embryonic development. In the adult fish, GFP was expressed in hematopoietic regions like the kidney, in agreement with the essential function of Prep1 in mouse hematopoiesis. Sequence comparison showed conservation from man to fish of the sequences around the TSS, within the first intron enhancer. Moreover, about 40% of the sequences spread throughout the 5 Kbof the zebrafish promoter are concentrated in the −3 to −5 Kb of the human upstream region.
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Fernandez-Diaz LC, Laurent A, Girasoli S, Turco M, Longobardi E, Iotti G, Jenkins NA, Fiorenza MT, Copeland NG, Blasi F. The absence of Prep1 causes p53-dependent apoptosis of mouse pluripotent epiblast cells. Development 2010; 137:3393-403. [PMID: 20826531 DOI: 10.1242/dev.050567] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Disruption of mouse Prep1, which codes for a homeodomain transcription factor, leads to embryonic lethality during post-implantation stages. Prep1(-/-) embryos stop developing after implantation and before anterior visceral endoderm (AVE) formation. In Prep1(-/-) embryos at E6.5 (onset of gastrulation), the AVE is absent and the proliferating extra-embryonic ectoderm and epiblast, marked by Bmp4 and Oct4, respectively, are reduced in size. At E.7.5, Prep1(-/-) embryos are small and very delayed, showing no evidence of primitive streak or of differentiated embryonic lineages. Bmp4 is expressed residually, while the reduced number of Oct4-positive cells is constant up to E8.5. At E6.5, Prep1(-/-) embryos retain a normal mitotic index but show a major increase in cleaved caspase 3 and TUNEL staining, indicating apoptosis. Therefore, the mouse embryo requires Prep1 when undergoing maximal expansion in cell number. Indeed, the phenotype is partially rescued in a p53(-/-), but not in a p16(-/-), background. Apoptosis is probably due to DNA damage as Atm downregulation exacerbates the phenotype. Despite this early lethal phenotype, Prep1 is not essential for ES cell establishment. A differential embryonic expression pattern underscores the unique function of Prep1 within the Meis-Prep family.
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Affiliation(s)
- Luis C Fernandez-Diaz
- IFOM, FIRC Institute of Molecular Oncology Foundation, IFOM-IEO Campus, via Adamello 16, Milan, Italy
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Micali N, Longobardi E, Iotti G, Ferrai C, Castagnaro L, Ricciardi M, Blasi F, Crippa MP. Down syndrome fibroblasts and mouse Prep1-overexpressing cells display increased sensitivity to genotoxic stress. Nucleic Acids Res 2010; 38:3595-604. [PMID: 20110257 PMCID: PMC2887940 DOI: 10.1093/nar/gkq019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
PREP1 (PKNOX1) maps in the Down syndrome (DS) critical region of chromosome 21, is overexpressed in some DS tissues and might be involved in the DS phenotype. By using fibroblasts from DS patients and by overexpressing Prep1 in F9 teratocarcinoma and Prep1i/i MEF to single out the role of the protein, we report that excess Prep1 increases the sensitivity of cells to genotoxic stress and the extent of the apoptosis directly correlates with the level of Prep1. The apoptotic response of Prep1-overexpressing cells is mediated by the pro-apoptotic p53 protein that we show is a direct target of Prep1, as its depletion reverts the apoptotic phenotype. The induction of p53 overcomes the anti-apoptotic role of Bcl-XL, previously shown to be also a Prep1 target, the levels of which are increased in Prep1-overexpressing cells as well. Our results provide a rationale for the involvement of PREP1 in the apoptotic phenotype of DS tissues and indicate that differences in Prep1 level can have drastic effects.
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Affiliation(s)
- Nicola Micali
- Laboratory of Molecular Dynamics of the Nucleus, Division of Genetics and Cell Biology, S. Raffaele Scientific Institute, via Olgettina 60, Milan, Italy
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Differences in human and chimpanzee gene expression patterns define an evolving network of transcription factors in brain. Proc Natl Acad Sci U S A 2009; 106:22358-63. [PMID: 20007773 DOI: 10.1073/pnas.0911376106] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Humans differ from other primates by marked differences in cognitive abilities and a significantly larger brain. These differences correlate with metabolic changes, as evidenced by the relative up-regulation of energy-related genes and metabolites in human brain. While the mechanisms underlying these evolutionary changes have not been elucidated, altered activities of key transcription factors (TFs) could play a pivotal role. To assess this possibility, we analyzed microarray data from five tissues from humans and chimpanzees. We identified 90 TF genes with significantly different expression levels in human and chimpanzee brain among which the rapidly evolving KRAB-zinc finger genes are markedly over-represented. The differentially expressed TFs cluster within a robust regulatory network consisting of two distinct but interlinked modules, one strongly associated with energy metabolism functions, and the other with transcription, vesicular transport, and ubiquitination. Our results suggest that concerted changes in a relatively small number of interacting TFs may coordinate major gene expression differences in human and chimpanzee brain.
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The estrogen receptor-alpha-induced microRNA signature regulates itself and its transcriptional response. Proc Natl Acad Sci U S A 2009; 106:15732-7. [PMID: 19706389 DOI: 10.1073/pnas.0906947106] [Citation(s) in RCA: 275] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Following estrogenic activation, the estrogen receptor-alpha (ERalpha) directly regulates the transcription of target genes via DNA binding. MicroRNAs (miRNAs) modulated by ERalpha have the potential to fine tune these regulatory systems and also provide an alternate mechanism that could impact on estrogen-dependent developmental and pathological systems. Through a microarray approach, we identify the subset of microRNAs (miRNAs) modulated by ERalpha, which include upregulation of miRNAs derived from the processing of the paralogous primary transcripts (pri-) mir-17-92 and mir-106a-363. Characterization of the mir-17-92 locus confirms that the ERalpha target protein c-MYC binds its promoter in an estrogen-dependent manner. We observe that levels of pri-mir-17-92 increase earlier than the mature miRNAs derived from it, implicating precursor cleavage modulation after transcription. Pri-mir-17-92 is immediately cleaved by DROSHA to pre-miR-18a, indicating that its regulation occurs during the formation of the mature molecule from the precursor. The clinical implications of this novel regulatory system were confirmed by demonstrating that pre-miR-18a was significantly upregulated in ERalpha-positive compared to ERalpha-negative breast cancers. Mechanistically, miRNAs derived from these paralogous pri-miRNAs (miR-18a, miR-19b, and miR-20b) target and downregulate ERalpha, while a subset of pri-miRNA-derived miRNAs inhibit protein translation of the ERalpha transcriptional p160 coactivator, AIB1. Therefore, different subsets of miRNAs identified act as part of a negative autoregulatory feedback loop. We propose that ERalpha, c-MYC, and miRNA transcriptional programs invoke a sophisticated network of interactions able to provide the wide range of coordinated cellular responses to estrogen.
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