1
|
Bi D, Shi M, Zheng D, Hu Q, Wang H, Peng L, Lou D, Zhang A, Hu Y. Mechanism underlying the targeted regulation of the SOD1 3'UTR by the AUF1/Dicer1/miR-155/SOD1 pathway in sodium arsenite-induced liver injury. Ecotoxicol Environ Saf 2022; 243:113990. [PMID: 35998476 DOI: 10.1016/j.ecoenv.2022.113990] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 06/13/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Arsenic (As) is a natural hepatotoxicity inducer that is ubiquitous in water, soil, coal, and food. Studies have found that arsenite exposure elicits increased mRNA transcription and decreased protein expression of SOD1 in vivo and in vitro; however, the specific mechanisms remain unclear. Here, we established a model of arsenic-induced chronic liver injury by providing rats with drinking water containing different concentrations of sodium arsenite (NaAsO2) and found that NaAsO2 exposure decreased the mRNA and protein levels of AUF1 and the protein level of SOD1 and elevated the mRNA and protein levels of Dicer1 and miR-155 and the mRNA level of SOD1. Overexpression of AUF1 under NaAsO2 stress in vitro induced Dicer1 mRNA and protein expression and decreased miR-155 levels, which could be reversed by AUF1 siRNA. In addition, miR-155 overexpression downregulated SOD1 mRNA and protein levels, although this change was inhibited after transfection with an miR-155 inhibitor. Taken together, our findings showed that NaAsO2 could upregulate Dicer1 mRNA and protein, thereby increasing miR-155 expression by downregulating AUF1 mRNA and protein expression. A dual-luciferase reporter assay indicated that miR-155 decreased the mRNA and protein levels of SOD1 by targeting the SOD1 3'UTR, resulting in liver injury. This study provides an important research basis for further understanding the factors underlying arsenic-induced liver injury to improve the prevention and control strategies for arsenism.
Collapse
Affiliation(s)
- Dingnian Bi
- Key Laboratory of Enviromental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang 550025, Guizhou, PR China
| | - Mingyang Shi
- Key Laboratory of Enviromental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang 550025, Guizhou, PR China
| | - Dan Zheng
- Guiyang Maternity and Child Health Hospital, Guizhou, PR China
| | - Qian Hu
- Key Laboratory of Enviromental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang 550025, Guizhou, PR China
| | - Hongling Wang
- Key Laboratory of Enviromental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang 550025, Guizhou, PR China
| | - Liuyu Peng
- Key Laboratory of Enviromental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang 550025, Guizhou, PR China
| | - Didong Lou
- Department of Forensic Medicine, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, Guizhou, PR China; Key Laboratory of Traditional Chinese Medicine Toxicology in Forensic Medicine, Guizhou Education Department, Guiyang 550025, Guizhou, PR China
| | - Aihua Zhang
- Key Laboratory of Enviromental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang 550025, Guizhou, PR China
| | - Yong Hu
- Key Laboratory of Enviromental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang 550025, Guizhou, PR China.
| |
Collapse
|
2
|
Feng H, Bao S, Rahman MA, Weyn-Vanhentenryck SM, Khan A, Wong J, Shah A, Flynn ED, Krainer AR, Zhang C. Modeling RNA-Binding Protein Specificity In Vivo by Precisely Registering Protein-RNA Crosslink Sites. Mol Cell 2019; 74:1189-1204.e6. [PMID: 31226278 PMCID: PMC6676488 DOI: 10.1016/j.molcel.2019.02.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 01/14/2019] [Accepted: 01/31/2019] [Indexed: 12/30/2022]
Abstract
RNA-binding proteins (RBPs) regulate post-transcriptional gene expression by recognizing short and degenerate sequence motifs in their target transcripts, but precisely defining their binding specificity remains challenging. Crosslinking and immunoprecipitation (CLIP) allows for mapping of the exact protein-RNA crosslink sites, which frequently reside at specific positions in RBP motifs at single-nucleotide resolution. Here, we have developed a computational method, named mCross, to jointly model RBP binding specificity while precisely registering the crosslinking position in motif sites. We applied mCross to 112 RBPs using ENCODE eCLIP data and validated the reliability of the discovered motifs by genome-wide analysis of allelic binding sites. Our analyses revealed that the prototypical SR protein SRSF1 recognizes clusters of GGA half-sites in addition to its canonical GGAGGA motif. Therefore, SRSF1 regulates splicing of a much larger repertoire of transcripts than previously appreciated, including HNRNPD and HNRNPDL, which are involved in multivalent protein assemblies and phase separation.
Collapse
Affiliation(s)
- Huijuan Feng
- Department of Systems Biology, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | - Suying Bao
- Department of Systems Biology, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | | | - Sebastien M Weyn-Vanhentenryck
- Department of Systems Biology, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | - Aziz Khan
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, 0318 Oslo, Norway
| | - Justin Wong
- Department of Systems Biology, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | - Ankeeta Shah
- Department of Systems Biology, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | - Elise D Flynn
- Department of Systems Biology, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA
| | - Adrian R Krainer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Chaolin Zhang
- Department of Systems Biology, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA.
| |
Collapse
|
3
|
Xu J, Hua X, Jin H, Zhu J, Li Y, Li J, Huang C. NFκB2 p52 stabilizes rhogdiβ mRNA by inhibiting AUF1 protein degradation via a miR-145/Sp1/USP8-dependent axis. Mol Carcinog 2019; 58:777-793. [PMID: 30604907 DOI: 10.1002/mc.22970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/26/2018] [Accepted: 12/27/2018] [Indexed: 12/29/2022]
Abstract
Although overexpression of the non-canonical NFκB subunit p52 has been observed in several tumors, the function and mechanism of p52 in bladder cancer (BC) are less well understood. Here, we aimed at understanding the role and mechanism underlying p52 regulation of BC invasion. Human p52 was stably knockdown with shRNA targeting p52 in two bladder cancer cell lines (T24 and UMUC3). Two constitutively expressing constructs, p52 and p100, were stably transfected in to T24 or UMUC3, respectively. The stable transfectants were used to determine function and mechanisms responsible for p52 regulation of BC invasion. We demonstrate that p52 mediates human BC invasion. Knockdown of p52 impaired bladder cancer invasion by reduction of rhogdiβ mRNA stability and expression. Positively regulation of rhogdiβ mRNA stability was mediated by p52 promoting AUF1 protein degradation, consequently resulting in reduction of AUF1 binding to rhogdiβ mRNA. Further studies indicated that AUF1 protein degradation was mediated by upregulating USP8 transcription, which was modulated by its negative regulatory transcription factor Sp1. Moreover, we found that p52 upregulated miR-145, which directly bound to the 3'-UTR of sp1 mRNA, leading to downregulation of Sp1 protein translation. Our results reveal a comprehensive pathway that p52 acts as a positive regulator of BC invasion by initiating a novel miR-145/Sp1/USP8/AUF1/RhoGDIβ axis. These findings provide insight into the understanding of p52 in the pathology of human BC invasion and progression, which may be useful information in the development of preventive and therapeutic approaches for using p52 as a potential target.
Collapse
Affiliation(s)
- Jiawei Xu
- Nelson Institute of Environmental Medicine, New York University, School of Medicine, New York, New York
- Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaohui Hua
- Nelson Institute of Environmental Medicine, New York University, School of Medicine, New York, New York
| | - Honglei Jin
- Nelson Institute of Environmental Medicine, New York University, School of Medicine, New York, New York
| | - Junlan Zhu
- Nelson Institute of Environmental Medicine, New York University, School of Medicine, New York, New York
| | - Yang Li
- Nelson Institute of Environmental Medicine, New York University, School of Medicine, New York, New York
| | - Jingxia Li
- Nelson Institute of Environmental Medicine, New York University, School of Medicine, New York, New York
| | - Chuangshu Huang
- Nelson Institute of Environmental Medicine, New York University, School of Medicine, New York, New York
| |
Collapse
|
4
|
Schmidtke L, Schrick K, Saurin S, Käfer R, Gather F, Weinmann-Menke J, Kleinert H, Pautz A. The KH-type splicing regulatory protein (KSRP) regulates type III interferon expression post-transcriptionally. Biochem J 2019; 476:333-352. [PMID: 30578289 DOI: 10.1042/bcj20180522] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 12/14/2018] [Accepted: 12/21/2018] [Indexed: 12/12/2022]
Abstract
Type III interferons (IFNs) are the latest members of the IFN family. They play an important role in immune defense mechanisms, especially in antiviral responses at mucosal sites. Moreover, they control inflammatory reactions by modulating neutrophil and dendritic cell functions. Therefore, it is important to identify cellular mechanisms involved in the control of type III IFN expression. All IFN family members contain AU-rich elements (AREs) in the 3'-untranslated regions (3'-UTR) of their mRNAs that determine mRNA half-life and consequently the expressional level of these cytokines. mRNA stability is controlled by different proteins binding to these AREs leading to either stabilization or destabilization of the respective target mRNA. The KH-type splicing regulatory protein KSRP (also named KHSRP) is an important negative regulator of ARE-containing mRNAs. Here, we identify the interferon lambda 3 (IFNL3) mRNA as a new KSRP target by pull-down and immunoprecipitation experiments, as well as luciferase reporter gene assays. We characterize the KSRP-binding site in the IFNL3 3'-UTR and demonstrate that KSRP regulates the mRNA half-life of the IFNL3 transcript. In addition, we detect enhanced expression of IFNL3 mRNA in KSRP-/- mice, establishing a negative regulatory function of KSRP in type III IFN expression also in vivo Besides KSRP the RNA-binding protein AUF1 (AU-rich element RNA-binding protein 1) also seems to be involved in the regulation of type III IFN mRNA expression.
Collapse
Affiliation(s)
- Lisa Schmidtke
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg-University, Obere Zahlbacher Str. 67, 55101 Mainz, Germany
| | - Katharina Schrick
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg-University, Obere Zahlbacher Str. 67, 55101 Mainz, Germany
| | - Sabrina Saurin
- First Medical Department, University Medical Center of the Johannes Gutenberg-University, Langenbeck Str. 1, 55101 Mainz, Germany
| | - Rudolf Käfer
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg-University, Obere Zahlbacher Str. 67, 55101 Mainz, Germany
| | - Fabian Gather
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg-University, Obere Zahlbacher Str. 67, 55101 Mainz, Germany
| | - Julia Weinmann-Menke
- First Medical Department, University Medical Center of the Johannes Gutenberg-University, Langenbeck Str. 1, 55101 Mainz, Germany
| | - Hartmut Kleinert
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg-University, Obere Zahlbacher Str. 67, 55101 Mainz, Germany
| | - Andrea Pautz
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg-University, Obere Zahlbacher Str. 67, 55101 Mainz, Germany
| |
Collapse
|
5
|
Trojanowicz B, Sekulla C, Dralle H, Hoang-Vu C. Expression of ARE-binding proteins AUF1 and HuR in follicular adenoma and carcinoma of thyroid gland. Neoplasma 2019; 63:371-7. [PMID: 26925783 DOI: 10.4149/305_150819n450] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Both adenylate-uridylate rich elements binding proteins AUF1 and HuR may participate in thyroid carcinoma progression. In this study we investigated the expression of both factors on a protein level with a special focus on follicular adenoma and follicular thyroid carcinoma. By employment of immunofluorescence and western blot on 68 thyroid tissues including 7 goiter, 16 follicular adenoma (4 adenomatous hyperplasia), 19 follicular thyroid carcinomas, 13 papillary thyroid carcinomas and 14 undifferentiated thyroid carcinomas we investigated protein expression of AUF1 and HuR. In addition to previous results we demonstrated that AUF1 and HuR are significantly up-regulated in carcinoma tissues as compared with follicular adenoma or goiter tissues. Furthermore, by evaluation of AUF1 or HuR expression, or combination of both proteins on total tissue lysates, we were able to demonstrate a significant difference between follicular adenoma and follicular thyroid carcinoma. Overexpression of AUF1 and HuR is a common finding observed in thyroid malignancy. Analysis of the tissues obtained by surgical resection as demonstrated in this study is comparable to a fine needle aspiration and in combination with AUF1/HuR immuno-analysis may support the conventional immunohistological investigations. The promising results of this study were performed on relatively small collective, but justify future development of a quick thyroid diagnostic test on larger cohort of the patients, especially for thyroid samples which are inadequate for histological examinations.
Collapse
|
6
|
Dogar AM, Pauchard-Batschulat R, Grisoni-Neupert B, Richman L, Paillusson A, Pradervand S, Hagenbüchle O, Ambrosini G, Schmid CD, Bucher P, Kühn LC. Short-lived AUF1 p42-binding mRNAs of RANKL and BCL6 have two distinct instability elements each. PLoS One 2018; 13:e0206823. [PMID: 30418981 PMCID: PMC6231638 DOI: 10.1371/journal.pone.0206823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 10/20/2018] [Indexed: 11/19/2022] Open
Abstract
Regulation of mRNA stability by RNA-protein interactions contributes significantly to quantitative aspects of gene expression. We have identified potential mRNA targets of the AU-rich element binding protein AUF1. Myc-tagged AUF1 p42 was induced in mouse NIH/3T3 cells and RNA-protein complexes isolated using anti-myc tag antibody beads. Bound mRNAs were analyzed with Affymetrix microarrays. We have identified 508 potential target mRNAs that were at least 3-fold enriched compared to control cells without myc-AUF1. 22.3% of the enriched mRNAs had an AU-rich cluster in the ARED Organism database, against 16.3% of non-enriched control mRNAs. The enrichment towards AU-rich elements was also visible by AREScore with an average value of 5.2 in the enriched mRNAs versus 4.2 in the control group. Yet, numerous mRNAs were enriched without a high ARE score. The enrichment of tetrameric and pentameric sequences suggests a broad AUF1 p42-binding spectrum at short U-rich sequences flanked by A or G. Still, some enriched mRNAs were highly unstable, as those of TNFSF11 (known as RANKL), KLF10, HES1, CCNT2, SMAD6, and BCL6. We have mapped some of the instability determinants. HES1 mRNA appeared to have a coding region determinant. Detailed analysis of the RANKL and BCL6 3’UTR revealed for both that full instability required two elements, which are conserved in evolution. In RANKL mRNA both elements are AU-rich and separated by 30 bases, while in BCL6 mRNA one is AU-rich and 60 bases from a non AU-rich element that potentially forms a stem-loop structure.
Collapse
Affiliation(s)
- Afzal M. Dogar
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
| | - Ramona Pauchard-Batschulat
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
| | - Barbara Grisoni-Neupert
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
| | - Larry Richman
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
| | - Alexandra Paillusson
- Center for Integrative Genomics (CIG), University of Lausanne, Génopode, Lausanne, Switzerland
| | - Sylvain Pradervand
- Center for Integrative Genomics (CIG), University of Lausanne, Génopode, Lausanne, Switzerland
| | - Otto Hagenbüchle
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
- Center for Integrative Genomics (CIG), University of Lausanne, Génopode, Lausanne, Switzerland
| | - Giovanna Ambrosini
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | | | - Philipp Bucher
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Lukas C. Kühn
- Ecole Polytechnique Fédérale de Lausanne (EPFL), SV—Sciences de la Vie, ISREC—Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland
- * E-mail:
| |
Collapse
|
7
|
Ghosh U, Adhya S. Posttranscriptional regulation of cyclin D1 by ARE-binding proteins AUF1 and HuR in cycling myoblasts. J Biosci 2018; 43:685-691. [PMID: 30207314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
RNA binding proteins (RBPs) can regulate the stability and/or translatability of messengerRNAs (mRNAs) through interactions with their 30-untranslated regions. However, individual mRNAs may be regulated simultaneously or successively by more than one RBP, as well as by Argonaute (AGO)-bound miRNAs; the coordination of these various influences on an individual mRNA is therefore complex and not well studied. In this report we examine the roles of two RBPs that bind to AU-rich elements (ARE) - AUF1 and HuR - in the stability and translation of cyclin D1 (Ccnd1) mRNA in rat myoblasts transiting the G phase of the cell cycle, and their interactions with miRNAs. Knockdown (KD) of AUF1 resulted in (1) transient upregulation of the mRNA level as well as an advancement of translation onset time (TOT) from 6 to 5 h post-serum addition, (2) loss of miRNA loading on AGO1 and AGO2 and (3) reduction in the level of AGO-1 and AGO-2 bound mRNA. In contrast, KD of HuR had no effect on the mRNA level, or on the AGO-mRNA complexes, but delayed TOT by 1 h independent of miRNA let-7. Thus the dynamics of RBP-mRNA binding and -RBP-AGO-miRNA interactions are coordinated to fine tune the expression of Ccnd1 in the G1 phase.
Collapse
Affiliation(s)
- Utpalendu Ghosh
- Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Calcutta 700 032, India
| | | |
Collapse
|
8
|
Abstract
HnRNP D, better known as AUF1, is an extensively studied protein that controls a variety of cellular pathways. Consequently, its expression has to be tightly regulated to prevent the onset of pathologies. In contrast, the cellular functions and regulation of its ubiquitously expressed paralog hnRNP DL are barely explored. Here, we present an intricate crosstalk between these two proteins. Both hnRNP D and DL are able to control their own expression by alternative splicing of cassette exons in their 3'UTRs. Exon inclusion produces mRNAs degraded by nonsense-mediated decay. Moreover, hnRNP D and DL control the expression of one another by the same mechanism. Thus, we identified two novel ways of how hnRNP D expression is controlled. The tight interconnection of expression control directly links hnRNP DL to hnRNP D-related diseases and emphasizes the importance of a systematic analysis of its cellular functions.
Collapse
Affiliation(s)
- Katrin Kemmerer
- Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Sandra Fischer
- Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Julia E Weigand
- Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| |
Collapse
|
9
|
Xiao ZD, Han L, Lee H, Zhuang L, Zhang Y, Baddour J, Nagrath D, Wood CG, Gu J, Wu X, Liang H, Gan B. Energy stress-induced lncRNA FILNC1 represses c-Myc-mediated energy metabolism and inhibits renal tumor development. Nat Commun 2017; 8:783. [PMID: 28978906 PMCID: PMC5627275 DOI: 10.1038/s41467-017-00902-z] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 08/04/2017] [Indexed: 01/13/2023] Open
Abstract
The roles of long non-coding RNAs in cancer metabolism remain largely unexplored. Here we identify FILNC1 (FoxO-induced long non-coding RNA 1) as an energy stress-induced long non-coding RNA by FoxO transcription factors. FILNC1 deficiency in renal cancer cells alleviates energy stress-induced apoptosis and markedly promotes renal tumor development. We show that FILNC1 deficiency leads to enhanced glucose uptake and lactate production through upregulation of c-Myc. Upon energy stress, FILNC1 interacts with AUF1, a c-Myc mRNA-binding protein, and sequesters AUF1 from binding c-Myc mRNA, leading to downregulation of c-Myc protein. FILNC1 is specifically expressed in kidney, and is downregulated in renal cell carcinoma; also, its low expression correlates with poor clinical outcomes in renal cell carcinoma. Together, our study not only identifies FILNC1 as a negative regulator of renal cancer with potential clinical value, but also reveals a regulatory mechanism by long non-coding RNAs to control energy metabolism and tumor development.FoxO are commonly down-regulated transcription factors and tumor suppressors in renal cell cancer (RCC). Here, the authors show that upon energy stress FoxOs induce the expression of the long non-coding RNA FILNC1, which inhibits survival of RCC by downregulating c-Myc and c-Myc-dependent metabolic rewiring.
Collapse
Affiliation(s)
- Zhen-Dong Xiao
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Leng Han
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston Medical School, 6431 Fannin St, Houston, TX, 77030, USA
| | - Hyemin Lee
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Li Zhuang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Yilei Zhang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Joelle Baddour
- Department of Chemical and Biomolecular Engineering, Rice University, 6100 Main Street, Houston, TX, 77005, USA
| | - Deepak Nagrath
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, 48105, USA
| | - Christopher G Wood
- Department of Urology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Jian Gu
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Xifeng Wu
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Han Liang
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
- Department of Systems Biology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Boyi Gan
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.
- Program of Genes and Development, and Program of Cancer Biology, The University of Texas Graduate School of Biomedical Sciences, Houston, TX, 77030, USA.
| |
Collapse
|
10
|
Friedrich S, Schmidt T, Schierhorn A, Lilie H, Szczepankiewicz G, Bergs S, Liebert UG, Golbik RP, Behrens SE. Arginine methylation enhances the RNA chaperone activity of the West Nile virus host factor AUF1 p45. RNA 2016; 22:1574-1591. [PMID: 27520967 PMCID: PMC5029455 DOI: 10.1261/rna.055269.115] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 07/07/2016] [Indexed: 06/06/2023]
Abstract
A prerequisite for the intracellular replication process of the Flavivirus West Nile virus (WNV) is the cyclization of the viral RNA genome, which enables the viral replicase to initiate RNA synthesis. Our earlier studies indicated that the p45 isoform of the cellular AU-rich element binding protein 1 (AUF1) has an RNA chaperone activity, which supports RNA cyclization and viral RNA synthesis by destabilizing a stem structure at the WNV RNA's 3'-end. Here we show that in mammalian cells, AUF1 p45 is consistently modified by arginine methylation of its C terminus. By a combination of different experimental approaches, we can demonstrate that the methyltransferase PRMT1 is necessary and sufficient for AUF1 p45 methylation and that PRMT1 is required for efficient WNV replication. Interestingly, in comparison to the nonmethylated AUF1 p45, the methylated AUF1 p45(aDMA) exhibits a significantly increased affinity to the WNV RNA termini. Further data also revealed that the RNA chaperone activity of AUF1 p45(aDMA) is improved and the methylated protein stimulates viral RNA synthesis considerably more efficiently than the nonmethylated AUF1 p45. In addition to its destabilizing RNA chaperone activity, we identified an RNA annealing activity of AUF1 p45, which is not affected by methylation. Arginine methylation of AUF1 p45 thus represents a specific determinant of its RNA chaperone activity while functioning as a WNV host factor. Our data suggest that the methylation modifies the conformation of AUF1 p45 and in this way affects its RNA binding and restructuring activities.
Collapse
Affiliation(s)
- Susann Friedrich
- Institute of Biochemistry and Biotechnology (NFI), Martin Luther University Halle-Wittenberg, 60120 Halle, Germany
| | - Tobias Schmidt
- Institute of Biochemistry and Biotechnology (NFI), Martin Luther University Halle-Wittenberg, 60120 Halle, Germany
| | - Angelika Schierhorn
- Institute of Biochemistry and Biotechnology (NFI), Martin Luther University Halle-Wittenberg, 60120 Halle, Germany
| | - Hauke Lilie
- Institute of Biochemistry and Biotechnology (NFI), Martin Luther University Halle-Wittenberg, 60120 Halle, Germany
| | | | - Sandra Bergs
- Institute of Virology, Leipzig University, 04130 Leipzig, Germany
| | - Uwe G Liebert
- Institute of Virology, Leipzig University, 04130 Leipzig, Germany
| | - Ralph P Golbik
- Institute of Biochemistry and Biotechnology (NFI), Martin Luther University Halle-Wittenberg, 60120 Halle, Germany
| | - Sven-Erik Behrens
- Institute of Biochemistry and Biotechnology (NFI), Martin Luther University Halle-Wittenberg, 60120 Halle, Germany
| |
Collapse
|
11
|
Navratilova Z, Novosadova E, Hagemann-Jensen M, Kullberg S, Kolek V, Grunewald J, Petrek M. Expression Profile of Six RNA-Binding Proteins in Pulmonary Sarcoidosis. PLoS One 2016; 11:e0161669. [PMID: 27575817 PMCID: PMC5004853 DOI: 10.1371/journal.pone.0161669] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 07/26/2016] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Sarcoidosis is characterised by up-regulation of cytokines and chemokine ligands/receptors and proteolytic enzymes. This pro-inflammatory profile is regulated post-transcriptionally by RNA-binding proteins (RBPs). We investigated in vivo expression of six RBPs (AUF1, HuR, NCL, TIA, TIAR, PCBP2) and two inhibitors of proteolytic enzymes (RECK, PTEN) in pulmonary sarcoidosis and compared it to the expression in four control groups of healthy individuals and patients with other respiratory diseases: chronic obstructive pulmonary disease (COPD), asthma and idiopathic interstitial pneumonias (IIPs). METHODS RT-PCR was used to quantify the mRNAs in bronchoalveolar (BA) cells obtained from 50 sarcoidosis patients, 23 healthy controls, 30 COPD, 19 asthmatic and 19 IIPs patients. Flow cytometry was used to assess intracellular protein expression of AUF1 and HuR in peripheral blood T lymphocytes (PBTLs) obtained from 9 sarcoidosis patients and 6 healthy controls. RESULTS Taking the stringent conditions for multiple comparisons into consideration, we consistently observed in the primary analysis including all patients regardless of smoking status as well as in the subsequent sub-analysis limited for never smokers that the BA mRNA expression of AUF1 (p<0.001), TIA (p<0.001), NCL (p<0.01) and RECK (p<0.05) was decreased in sarcoidosis compared to healthy controls. TIA mRNA was also decreased in sarcoidosis compared to both obstructive pulmonary diseases (COPD and asthma; p<0.001) but not compared to IIPs. There were several positive correlations between RECK mRNA and RBP mRNAs in BA cells. Also sarcoidosis CD3+, CD4+ and CD8+ PBTLs displayed lower mean fluorescence intensity of AUF1 (p≤0.02) and HuR (p≤0.03) proteins than control healthy PBTLs. CONCLUSION mRNA expressions of three RBPs (AUF1, TIA and NCL) and their potential target mRNA encoding RECK in BA cells and additionally protein expression of AUF1 and HuR in PBTLs were down-regulated in our sarcoidosis patients compared to healthy individuals. Its significance, e.g. for stability of mRNAs encoding pro-inflammatory factors, should be further explored in sarcoidosis.
Collapse
Affiliation(s)
- Zdenka Navratilova
- Laboratory of Immunogenomics and Immunoproteomics, Department of Pathological Physiology, Faculty of Medicine and Dentistry Palacky University, Olomouc, Czech Republic
- Respiratory Medicine Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Eva Novosadova
- Laboratory of Immunogenomics and Immunoproteomics, Department of Pathological Physiology, Faculty of Medicine and Dentistry Palacky University, Olomouc, Czech Republic
| | - Michael Hagemann-Jensen
- Respiratory Medicine Unit, Department of Medicine, Solna & Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Susanna Kullberg
- Respiratory Medicine Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Vitezslav Kolek
- Department of Respiratory Medicine, Palacky University, Olomouc, Czech Republic
| | - Johan Grunewald
- Respiratory Medicine Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Martin Petrek
- Laboratory of Immunogenomics and Immunoproteomics, Department of Pathological Physiology, Faculty of Medicine and Dentistry Palacky University, Olomouc, Czech Republic
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| |
Collapse
|
12
|
Mou Z, Hyde TM, Lipska BK, Martinowich K, Wei P, Ong CJ, Hunter LA, Palaguachi GI, Morgun E, Teng R, Lai C, Condarco TA, Demidowich AP, Krause AJ, Marshall LJ, Haack K, Voruganti VS, Cole SA, Butte NF, Comuzzie AG, Nalls MA, Zonderman AB, Singleton AB, Evans MK, Martin B, Maudsley S, Tsao JW, Kleinman JE, Yanovski JA, Han JC. Human Obesity Associated with an Intronic SNP in the Brain-Derived Neurotrophic Factor Locus. Cell Rep 2015; 13:1073-1080. [PMID: 26526993 DOI: 10.1016/j.celrep.2015.09.065] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 08/27/2015] [Accepted: 09/23/2015] [Indexed: 12/26/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) plays a key role in energy balance. In population studies, SNPs of the BDNF locus have been linked to obesity, but the mechanism by which these variants cause weight gain is unknown. Here, we examined human hypothalamic BDNF expression in association with 44 BDNF SNPs. We observed that the minor C allele of rs12291063 is associated with lower human ventromedial hypothalamic BDNF expression (p < 0.001) and greater adiposity in both adult and pediatric cohorts (p values < 0.05). We further demonstrated that the major T allele for rs12291063 possesses a binding capacity for the transcriptional regulator, heterogeneous nuclear ribonucleoprotein D0B, knockdown of which disrupts transactivation by the T allele. Binding and transactivation functions are both disrupted by substituting C for T. These findings provide a rationale for BDNF augmentation as a targeted treatment for obesity in individuals who have the rs12291063 CC genotype.
Collapse
Affiliation(s)
- Zongyang Mou
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA
| | - Thomas M Hyde
- The Lieber Institute for Brain Development, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Barbara K Lipska
- Human Brain Collection Core, National Institute of Mental Health (NIMH), NIH, Bethesda, MD 20892, USA
| | - Keri Martinowich
- The Lieber Institute for Brain Development, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Peter Wei
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Departments of Neurology and Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Chiew-Jen Ong
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Departments of Neurology and Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Lindsay A Hunter
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Departments of Neurology and Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Gladys I Palaguachi
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Departments of Neurology and Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Eva Morgun
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA
| | - Rujia Teng
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA
| | - Chen Lai
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Departments of Neurology and Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Tania A Condarco
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA
| | - Andrew P Demidowich
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA
| | - Amanda J Krause
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA
| | - Leslie J Marshall
- Preclinical Microbicide & Prevention Research Branch, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Karin Haack
- Department of Genetics, Texas Biomedical Research Institute and Southwest National Primate Research Center, San Antonio, TX 78245, USA
| | - V Saroja Voruganti
- Department of Genetics, Texas Biomedical Research Institute and Southwest National Primate Research Center, San Antonio, TX 78245, USA; Department of Nutrition and UNC Nutrition Research Institute, University of North Carolina, Chapel Hill, Kannapolis, NC 28081, USA
| | - Shelley A Cole
- Department of Genetics, Texas Biomedical Research Institute and Southwest National Primate Research Center, San Antonio, TX 78245, USA
| | - Nancy F Butte
- USDA/ARS Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Anthony G Comuzzie
- Department of Genetics, Texas Biomedical Research Institute and Southwest National Primate Research Center, San Antonio, TX 78245, USA
| | - Michael A Nalls
- Molecular Genetics Section, National Institute of Aging (NIA), Bethesda, MD 20892, USA
| | | | - Andrew B Singleton
- Molecular Genetics Section, National Institute of Aging (NIA), Bethesda, MD 20892, USA
| | - Michele K Evans
- Health Disparities Research Section, NIA, Baltimore, MD 21224, USA
| | | | - Stuart Maudsley
- Receptor Pharmacology Unit, NIA, Baltimore, MD 21224, USA; Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, 2610 Wilrijk, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, 2610 Wilrijk, Belgium
| | - Jack W Tsao
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Departments of Neurology and Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; Department of Neurology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Joel E Kleinman
- The Lieber Institute for Brain Development, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jack A Yanovski
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA
| | - Joan C Han
- Unit on Metabolism and Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), NIH, Bethesda, MD 20892, USA; Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Children's Foundation Research Institute, Le Bonheur Children's Hospital, Memphis, TN 38103, USA.
| |
Collapse
|
13
|
Lin JY, Brewer G, Li ML. HuR and Ago2 Bind the Internal Ribosome Entry Site of Enterovirus 71 and Promote Virus Translation and Replication. PLoS One 2015; 10:e0140291. [PMID: 26451954 PMCID: PMC4599798 DOI: 10.1371/journal.pone.0140291] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 09/23/2015] [Indexed: 02/05/2023] Open
Abstract
EV71 (enterovirus 71) RNA contains an internal ribosomal entry site (IRES) that directs cap-independent initiation of translation. IRES-dependent translation requires the host’s translation initiation factors and IRES-associated trans-acting factors (ITAFs). We reported recently that mRNA decay factor AUF1 is a negative-acting ITAF that binds IRES stem-loop II. We also reported that the small RNA-processing enzyme Dicer produces at least four small RNAs (vsRNAs) from the EV71 IRES. One of these, vsRNA1, derived from IRES stem-loop II, reduces IRES activity and virus replication. Since its mechanism of action is unknown, we hypothesized that it might control association of ITAFs with the IRES. Here, we identified the mRNA stability factor HuR and the RISC subunit Argonaute 2 (Ago2) as two ITAFs that bind stem-loop II. In contrast to AUF1, HuR and Ago2 promote EV71 IRES activity and virus replication. In vitro RNA-binding assays revealed that vsRNA1 can alter association of Ago2, HuR, and AUF1 with stem-loop II. This presents a possible mechanism by which vsRNA1 could control viral translation and replication.
Collapse
Affiliation(s)
- Jing-Yi Lin
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Gary Brewer
- Department of Biochemistry & Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, United States of America
| | - Mei-Ling Li
- Department of Biochemistry & Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, United States of America
- * E-mail:
| |
Collapse
|
14
|
Zhang S, Xue J, Zheng J, Wang S, Zhou J, Jiao Y, Geng Y, Wu J, Hannafon BN, Ding WQ. The superoxide dismutase 1 3'UTR maintains high expression of the SOD1 gene in cancer cells: The involvement of the RNA-binding protein AUF-1. Free Radic Biol Med 2015; 85:33-44. [PMID: 25908445 PMCID: PMC4508224 DOI: 10.1016/j.freeradbiomed.2015.04.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 03/14/2015] [Accepted: 04/10/2015] [Indexed: 12/21/2022]
Abstract
Superoxide dismutase 1 (SOD1) is ubiquitously expressed and the predominant dismutase in the cytoplasm. Whereas transcriptional regulation of the SOD1 gene has been well characterized, posttranscriptional regulation of the gene remains largely unknown in eukaryotes. In this study, a full-length 3'UTR of the SOD1 transcript was cloned and characterized for its ability to regulate SOD1 gene expression in human cancer cells. Inclusion of the SOD1 3'UTR in the pGL3 reporter construct dramatically enhanced the reporter activity by 10- to 220-fold in various cell lines. RT-PCR analysis, however, indicated that the reporter gene mRNA levels were only modestly altered by the SOD1 3'UTR, suggesting that the SOD1 3'UTR enhances the reporter gene activity not simply by stabilizing the mRNA but primarily by promoting translation of the protein. Bioinformatics analysis showed multiple stem and loop structures of the SOD1 3'UTR, and alterations in this secondary structure led to remarkably reduced reporter gene activity. Importantly, introducing the SOD1 3'UTR into cancer cells attenuated endogenous SOD1 expression in a concentration-dependent manner, indicating the involvement of RNA trans-acting factors in this process. Using siRNA and RNA immunoprecipitation techniques, we identified AUF-1, an RNA-binding protein, as a positive regulator of SOD1 expression through its 3'UTR. Consequently, AUF-1 was found to regulate redox balance in our cell model systems. Furthermore, in human ovarian, esophageal, and pancreatic cancer tissues, the expression of SOD1 was significantly correlated with that of AUF-1, further supporting the importance of AUF-1 in regulating SOD1 gene expression.
Collapse
Affiliation(s)
- Shuyu Zhang
- School of Radiation Medicine and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Medical College of Soochow University, Suzhou 215123, China; Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Jing Xue
- School of Radiation Medicine and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Medical College of Soochow University, Suzhou 215123, China; Department of Radio-Oncology, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou 215001, China
| | - Jie Zheng
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Shuai Wang
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Jundong Zhou
- Department of Radio-Oncology, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou 215001, China
| | - Yang Jiao
- School of Radiation Medicine and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Medical College of Soochow University, Suzhou 215123, China
| | - Yangyang Geng
- School of Radiation Medicine and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Medical College of Soochow University, Suzhou 215123, China
| | - Jinchang Wu
- Department of Radio-Oncology, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou 215001, China
| | - Bethany N Hannafon
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Wei-Qun Ding
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| |
Collapse
|
15
|
Díaz-Muñoz MD, Bell SE, Turner M. Deletion of AU-rich elements within the Bcl2 3'UTR reduces protein expression and B cell survival in vivo. PLoS One 2015; 10:e0116899. [PMID: 25680182 PMCID: PMC4332480 DOI: 10.1371/journal.pone.0116899] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 12/16/2014] [Indexed: 11/18/2022] Open
Abstract
Post-transcriptional mRNA regulation by RNA binding proteins (RBPs) associated with AU-rich elements (AREs) present in the 3' untranslated region (3'UTR) of specific mRNAs modulates transcript stability and translation in eukaryotic cells. Here we have functionally characterised the importance of the AREs present within the Bcl2 3'UTR in order to maintain Bcl2 expression. Gene targeting deletion of 300 nucleotides of the Bcl2 3'UTR rich in AREs diminishes Bcl2 mRNA stability and protein levels in primary B cells, decreasing cell lifespan. Generation of chimeric mice indicates that Bcl2-ARE∆/∆ B cells have an intrinsic competitive disadvantage compared to wild type cells. Biochemical assays and predictions using a bioinformatics approach show that several RBPs bind to the Bcl2 AREs, including AUF1 and HuR proteins. Altogether, association of RBPs to Bcl2 AREs contributes to Bcl2 protein expression by stabilizing Bcl2 mRNA and promotes B cell maintenance.
Collapse
Affiliation(s)
- Manuel D. Díaz-Muñoz
- Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, United Kingdom
| | - Sarah E. Bell
- Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, United Kingdom
| | - Martin Turner
- Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, United Kingdom
- * E-mail:
| |
Collapse
|
16
|
Ishii T, Hayakawa H, Sekiguchi T, Adachi N, Sekiguchi M. Role of Auf1 in elimination of oxidatively damaged messenger RNA in human cells. Free Radic Biol Med 2015; 79:109-16. [PMID: 25486179 DOI: 10.1016/j.freeradbiomed.2014.11.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 11/22/2014] [Accepted: 11/26/2014] [Indexed: 11/22/2022]
Abstract
In aerobically growing cells, in which reactive oxygen species are produced, the guanine base of RNA is oxidized to 8-oxo-7,8-dihydroguanine, which induces alterations in gene expression. Here we show that the human Auf1 protein, also called HNRNPD, binds specifically to RNA containing this oxidized base and may be involved in cellular processes associated with managing the problems caused by RNA oxidation. Auf1-deficient cells were constructed from human HeLa and Nalm-6 lines using two different targeting procedures. Both types of Auf1-deficient cells are viable, but exhibit growth retardation. The stability of messenger RNA for four different housekeeping genes was determined in Auf1-deficient and -proficient cells, treated with or without hydrogen peroxide. The level of oxidized messenger RNA was considerably higher in Auf1-deficient cells than in Auf1-proficient cells. Auf1 may play a role in the elimination of oxidized RNA, which is required for the maintenance of proper gene expression under conditions of oxidative stress.
Collapse
Affiliation(s)
- Takashi Ishii
- Frontier Research Center and Department of Biochemistry, Fukuoka Dental College, Fukuoka 814-0193, Japan
| | - Hiroshi Hayakawa
- Frontier Research Center and Department of Biochemistry, Fukuoka Dental College, Fukuoka 814-0193, Japan
| | - Takeshi Sekiguchi
- Department of Molecular Biology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Noritaka Adachi
- Graduate School of Nanobioscience, Yokohama City University, Yokohama 236-0027, Japan
| | - Mutsuo Sekiguchi
- Frontier Research Center and Department of Biochemistry, Fukuoka Dental College, Fukuoka 814-0193, Japan.
| |
Collapse
|
17
|
Wu S, Lin L, Zhao W, Li X, Wang Y, Si X, Wang T, Wu H, Zhai X, Zhong X, Gao S, Tong L, Xu Z, Zhong Z. AUF1 is recruited to the stress granules induced by coxsackievirus B3. Virus Res 2014; 192:52-61. [PMID: 25148713 DOI: 10.1016/j.virusres.2014.08.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 08/05/2014] [Accepted: 08/11/2014] [Indexed: 11/18/2022]
Abstract
Stress granules (SGs) are cytoplasmic granules that are formed in cells when stress occurs. In this study, we found that SGs formed in cells infected with coxsackievirus B3 (CVB3), evidenced with the co-localization of some accepted SG markers in the viral infection-induced granules. We further discovered that adenosine-uridine (AU)-rich element RNA binding factor 1 (AUF1), which can bind to mRNAs and regulate their translation, was recruited to the SGs in response to high dose of CVB3 by detecting the co-localization of AUF1 with SG markers. Similar results were also observed in the enterovirus 71 (EV71)-infected cells. Finally, we demonstrated that AUF1 was also recruited to arsenite-induced SGs, suggesting that the recruitment of AUF1 to SG is not a specific response to viral infection. In summary, our data indicate that both CVB3 and EV71 infections can induce SG formation, and AUF1 is a novel SG component upon the viral infections. Our findings may shed light on understanding the picornavirus-host interaction.
Collapse
Affiliation(s)
- Shuo Wu
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Lexun Lin
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Wenran Zhao
- Department of Cell Biology, Harbin Medical University, Harbin 150081, China
| | - Xiaobo Li
- Department of Pathology, Harbin Medical University, Harbin 150081, China
| | - Yan Wang
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Xiaoning Si
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Tianying Wang
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Heng Wu
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Xia Zhai
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Xiaoyan Zhong
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Shuoyang Gao
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Lei Tong
- Department of Microbiology, Harbin Medical University, Harbin 150081, China
| | - Zhikai Xu
- Department of Microbiology, School of Basic Medicine, Fourth Military Medical University, Xi'an 710032, China.
| | - Zhaohua Zhong
- Department of Microbiology, Harbin Medical University, Harbin 150081, China.
| |
Collapse
|
18
|
Lin JY, Li ML, Brewer G. mRNA decay factor AUF1 binds the internal ribosomal entry site of enterovirus 71 and inhibits virus replication. PLoS One 2014; 9:e103827. [PMID: 25077793 PMCID: PMC4117571 DOI: 10.1371/journal.pone.0103827] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 07/07/2014] [Indexed: 02/05/2023] Open
Abstract
AU-rich element binding factor 1 (AUF1) has a role in the replication cycles of different viruses. Here we demonstrate that AUF1 binds the internal ribosome entry site (IRES) of enterovirus 71 (EV71) and negatively regulates IRES-dependent translation. During EV71 infection, AUF1 accumulates in the cytoplasm where viral replication occurs, whereas AUF1 localizes predominantly in the nucleus in mock-infected cells. AUF1 knockdown in infected cells increases IRES activity and synthesis of viral proteins. Taken together, the results suggest that AUF1 interacts with the EV71 IRES to negatively regulate viral translation and replication.
Collapse
Affiliation(s)
- Jing-Yi Lin
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Mei-Ling Li
- Department of Biochemistry & Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, United States of America
| | - Gary Brewer
- Department of Biochemistry & Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, New Jersey, United States of America
| |
Collapse
|
19
|
Krishnan N, Titus MA, Thapar R. The prolyl isomerase pin1 regulates mRNA levels of genes with short half-lives by targeting specific RNA binding proteins. PLoS One 2014; 9:e85427. [PMID: 24416409 PMCID: PMC3887067 DOI: 10.1371/journal.pone.0085427] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 12/04/2013] [Indexed: 01/13/2023] Open
Abstract
The peptidyl-prolyl isomerase Pin1 is over-expressed in several cancer tissues is a potential prognostic marker in prostate cancer, and Pin1 ablation can suppress tumorigenesis in breast and prostate cancers. Pin1 can co-operate with activated ErbB2 or Ras to enhance tumorigenesis. It does so by regulating the activity of proteins that are essential for gene expression and cell proliferation. Several targets of Pin1 such as c-Myc, the Androgen Receptor, Estrogen Receptor-alpha, Cyclin D1, Cyclin E, p53, RAF kinase and NCOA3 are deregulated in cancer. At the posttranscriptional level, emerging evidence indicates that Pin1 also regulates mRNA decay of histone mRNAs, GM-CSF, Pth, and TGFβ mRNAs by interacting with the histone mRNA specific protein SLBP, and the ARE-binding proteins AUF1 and KSRP, respectively. To understand how Pin1 may affect mRNA abundance on a genome-wide scale in mammalian cells, we used RNAi along with DNA microarrays to identify genes whose abundance is significantly altered in response to a Pin1 knockdown. Functional scoring of differentially expressed genes showed that Pin1 gene targets control cell adhesion, leukocyte migration, the phosphatidylinositol signaling system and DNA replication. Several mRNAs whose abundance was significantly altered by Pin1 knockdown contained AU-rich element (ARE) sequences in their 3' untranslated regions. We identified HuR and AUF1 as Pin1 interacting ARE-binding proteins in vivo. Pin1 was also found to stabilize all core histone mRNAs in this study, thereby validating our results from a previously published study. Statistical analysis suggests that Pin1 may target the decay of essential mRNAs that are inherently unstable and have short to medium half-lives. Thus, this study shows that an important biological role of Pin1 is to regulate mRNA abundance and stability by interacting with specific RNA-binding proteins that may play a role in cancer progression.
Collapse
Affiliation(s)
- Nithya Krishnan
- Hauptman-Woodward Medical Research Institute, SUNY at Buffalo, New York, United States of America
| | - Mark A. Titus
- Department of Genitourinary Medical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas, United States of America
| | - Roopa Thapar
- Hauptman-Woodward Medical Research Institute, SUNY at Buffalo, New York, United States of America
- Department of Structural Biology, SUNY at Buffalo, New York, United States of America
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas, United States of America
| |
Collapse
|
20
|
Cathcart AL, Rozovics JM, Semler BL. Cellular mRNA decay protein AUF1 negatively regulates enterovirus and human rhinovirus infections. J Virol 2013; 87:10423-34. [PMID: 23903828 PMCID: PMC3807403 DOI: 10.1128/jvi.01049-13] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 07/19/2013] [Indexed: 01/12/2023] Open
Abstract
To successfully complete their replication cycles, picornaviruses modify several host proteins to alter the cellular environment to favor virus production. One such target of viral proteinase cleavage is AU-rich binding factor 1 (AUF1), a cellular protein that binds to AU-rich elements, or AREs, in the 3' noncoding regions (NCRs) of mRNAs to affect the stability of the RNA. Previous studies found that, during poliovirus or human rhinovirus infection, AUF1 is cleaved by the viral proteinase 3CD and that AUF1 can interact with the long 5' NCR of these viruses in vitro. Here, we expand on these initial findings to demonstrate that all four isoforms of AUF1 bind directly to stem-loop IV of the poliovirus 5' NCR, an interaction that is inhibited through proteolytic cleavage of AUF1 by the viral proteinase 3CD. Endogenous AUF1 was observed to relocalize to the cytoplasm of infected cells in a viral protein 2A-driven manner and to partially colocalize with the viral protein 3CD. We identify a negative role for AUF1 in poliovirus infection, as AUF1 inhibited viral translation and, ultimately, overall viral titers. Our findings also demonstrate that AUF1 functions as an antiviral factor during infection by coxsackievirus or human rhinovirus, suggesting a common mechanism that targets these related picornaviruses.
Collapse
Affiliation(s)
- Andrea L Cathcart
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA 92697 USA
| | | | | |
Collapse
|
21
|
Al-Khalaf HH, Aboussekhra A. p16(INK4A) positively regulates p21(WAF1) expression by suppressing AUF1-dependent mRNA decay. PLoS One 2013; 8:e70133. [PMID: 23894605 PMCID: PMC3720951 DOI: 10.1371/journal.pone.0070133] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2013] [Accepted: 06/17/2013] [Indexed: 01/01/2023] Open
Abstract
Background p16INK4a and p21WAF1 are two independent cyclin-dependent kinase inhibitors encoded by the CDKN2A and CDKN1A genes, respectively. p16INK4a and p21WAF1 are similarly involved in various anti-cancer processes, including the regulation of the critical G1 to S phase transition of the cell cycle, senescence and apoptosis. Therefore, we sought to elucidate the molecular mechanisms underlying the link between these two important tumor suppressor proteins. Methodology/Principal Findings We have shown here that the p16INK4a protein positively controls the expression of p21WAF1 in both human and mouse cells. p16INK4a stabilizes the CDKN1A mRNA through negative regulation of the mRNA decay-promoting AUF1 protein. Immunoprecipitation of AUF1-associated RNAs followed by quantitative RT-PCR indicated that endogenous AUF1 binds to the CDKN1A mRNA in a p16INK4A-dependent manner. Furthermore, while AUF1 down-regulation increased the expression level of the CDKN1A mRNA, the concurrent knockdown of AUF1 and CDKN2A, using specific silencing RNAs, restored the normal expression of the gene. Moreover, we used EGFP reporter fused to the CDKN2A AU-rich element (ARE) to demonstrate that p16INK4A regulation of the CDKN1A mRNA is AUF1- and ARE-dependent. Furthermore, ectopic expression of p16INK4A in p16INK4A-deficient breast epithelial MCF-10A cells significantly increased the level of p21WAF1, with no effect on cell proliferation. In addition, we have shown direct correlation between p16INK4a and p21WAF1 levels in various cancer cell lines. Conclusion/Significance These findings show that p16INK4a stabilizes the CDKN1A mRNA in an AUF1-dependent manner, and further confirm the presence of a direct link between the 2 important cancer-related pathways, pRB/p16INK4A and p14ARF/p53/p21WAF1.
Collapse
Affiliation(s)
- Huda H. Al-Khalaf
- Department of Molecular Oncology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- The Joint Center for Genomics Research, King Abdulaziz City for Science and Technology, Riyadh, KSA
| | - Abdelilah Aboussekhra
- Department of Molecular Oncology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- * E-mail:
| |
Collapse
|
22
|
Ehlers C, Schirmer S, Kehlenbach RH, Hauber J, Chemnitz J. Post-transcriptional regulation of CD83 expression by AUF1 proteins. Nucleic Acids Res 2013; 41:206-19. [PMID: 23161671 PMCID: PMC3592417 DOI: 10.1093/nar/gks1069] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 09/27/2012] [Accepted: 10/11/2012] [Indexed: 12/31/2022] Open
Abstract
Mature dendritic cells (DC), activated lymphocytes, mononuclear cells and neutrophils express CD83, a surface protein apparently necessary for effective DC-mediated activation of naïve T-cells and T-helper cells, thymic T-cell maturation and the regulation of B-cell activation and homeostasis. Although a defined ligand of CD83 remains elusive, the multiple cellular subsets expressing CD83, as well as its numerous potential implications in immunological processes suggest that CD83 plays an important regulatory role in the mammalian immune system. Lately, nucleocytoplasmic translocation of CD83 mRNA was shown to be mediated by direct interaction between the shuttle protein HuR and a novel post-transcriptional regulatory element (PRE) located in the CD83 transcript's coding region. Interestingly, this interaction commits the CD83 mRNA to efficient nuclear export through the CRM1 protein translocation pathway. More recently, the cellular phosphoprotein and HuR ligand ANP32B (APRIL) was demonstrated to be directly involved in this intracellular transport process by linking the CD83 mRNA:HuR ribonucleoprotein (RNP) complex with the CRM1 export receptor. Casein kinase II regulates this process by phosphorylating ANP32B. Here, we identify another RNA binding protein, AUF1 (hnRNP D) that directly interacts with CD83 PRE. Unlike HuR:PRE binding, this interaction has no impact on intracellular trafficking of CD83 mRNA-containing complexes; but it does regulate translation of CD83 mRNA. Thus, our data shed more light on the complex process of post-transcriptional regulation of CD83 expression. Interfering with this process may provide a novel strategy for inhibiting CD83, and thereby cellular immune activation.
Collapse
Affiliation(s)
- Christina Ehlers
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, D-20251 Hamburg and Zentrum für Biochemie und Molekulare Zellbiologie, Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Susann Schirmer
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, D-20251 Hamburg and Zentrum für Biochemie und Molekulare Zellbiologie, Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Ralph H. Kehlenbach
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, D-20251 Hamburg and Zentrum für Biochemie und Molekulare Zellbiologie, Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Joachim Hauber
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, D-20251 Hamburg and Zentrum für Biochemie und Molekulare Zellbiologie, Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Jan Chemnitz
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, D-20251 Hamburg and Zentrum für Biochemie und Molekulare Zellbiologie, Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| |
Collapse
|
23
|
Rozovics JM, Chase AJ, Cathcart AL, Chou W, Gershon PD, Palusa S, Wilusz J, Semler BL. Picornavirus modification of a host mRNA decay protein. mBio 2012; 3:e00431-12. [PMID: 23131833 PMCID: PMC3487778 DOI: 10.1128/mbio.00431-12] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 10/12/2012] [Indexed: 01/27/2023] Open
Abstract
UNLABELLED Due to the limited coding capacity of picornavirus genomic RNAs, host RNA binding proteins play essential roles during viral translation and RNA replication. Here we describe experiments suggesting that AUF1, a host RNA binding protein involved in mRNA decay, plays a role in the infectious cycle of picornaviruses such as poliovirus and human rhinovirus. We observed cleavage of AUF1 during poliovirus or human rhinovirus infection, as well as interaction of this protein with the 5' noncoding regions of these viral genomes. Additionally, the picornavirus proteinase 3CD, encoded by poliovirus or human rhinovirus genomic RNAs, was shown to cleave all four isoforms of recombinant AUF1 at a specific N-terminal site in vitro. Finally, endogenous AUF1 was found to relocalize from the nucleus to the cytoplasm in poliovirus-infected HeLa cells to sites adjacent to (but distinct from) putative viral RNA replication complexes. IMPORTANCE This study derives its significance from reporting how picornaviruses like poliovirus and human rhinovirus proteolytically cleave a key player (AUF1) in host mRNA decay pathways during viral infection. Beyond cleavage of AUF1 by the major viral proteinase encoded in picornavirus genomes, infection by poliovirus results in the relocalization of this host cell RNA binding protein from the nucleus to the cytoplasm. The alteration of both the physical state of AUF1 and its cellular location illuminates how small RNA viruses manipulate the activities of host cell RNA binding proteins to ensure a faithful intracellular replication cycle.
Collapse
Affiliation(s)
| | | | | | | | | | - Saiprasad Palusa
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Jeffrey Wilusz
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | | |
Collapse
|
24
|
Abstract
Epstein-Barr virus (EBV)-infected cells express two noncoding RNAs called EBV-encoded RNA (EBER) 1 and EBER2. Despite their high abundance in the nucleus (about 10(6) copies), the molecular function of these noncoding RNAs has remained elusive. Here, we report that the insertion into EBER1 of an RNA aptamer that binds the bacteriophage MS2 coat protein allows the isolation of EBER1 and associated protein partners. By combining MS2-mediated selection with stable isotope labeling of amino acids in cell culture (SILAC) and analysis by mass spectrometry, we identified AUF1 (AU-rich element binding factor 1)/hnRNP D (heterogeneous nuclear ribonucleoprotein D) as an interacting protein of EBER1. AUF1 exists as four isoforms generated by alternative splicing and is best known for its role in destabilizing mRNAs upon binding to AU-rich elements (AREs) in their 3' untranslated region (UTR). Using UV crosslinking, we demonstrate that predominantly the p40 isoform of AUF1 interacts with EBER1 in vivo. Electrophoretic mobility shift assays show that EBER1 can compete for the binding of the AUF1 p40 isoform to ARE-containing RNA. Given the high abundance of EBER1 in EBV-positive cells, EBER1 may disturb the normal homeostasis between AUF1 and ARE-containing mRNAs or compete with other AUF1-interacting targets in cells latently infected by EBV.
Collapse
Affiliation(s)
- Nara Lee
- Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06536, USA
| | - Genaro Pimienta
- Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06536, USA
| | - Joan A. Steitz
- Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06536, USA
- Corresponding authorE-mail
| |
Collapse
|
25
|
Huang CY, Shih CM, Tsao NW, Chen YH, Li CY, Chang YJ, Chang NC, Ou KL, Lin CY, Lin YW, Nien CH, Lin FY. GroEL1, from Chlamydia pneumoniae, induces vascular adhesion molecule 1 expression by p37(AUF1) in endothelial cells and hypercholesterolemic rabbit. PLoS One 2012; 7:e42808. [PMID: 22900050 PMCID: PMC3416774 DOI: 10.1371/journal.pone.0042808] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 07/11/2012] [Indexed: 12/20/2022] Open
Abstract
The expression of vascular adhesion molecule-1 (VCAM-1) by endothelial cells may play a major role in atherogenesis. The actual mechanisms of chlamydia pneumoniae (C. pneumoniae) relate to atherogenesis are unclear. We investigate the influence of VCAM-1 expression in the GroEL1 from C. pneumoniae-administered human coronary artery endothelial cells (HCAECs) and hypercholesterolemic rabbits. In this study, we constructed the recombinant GroEL1 from C. pneumoniae. The HCAECs/THP-1 adhesion assay, tube formation assay, western blotting, enzyme-linked immunosorbent assay, actinomycin D chase experiment, luciferase reporter assay, and immunohistochemical stainings were performed. The results show that GroEL1 increased both VCAM-1expression and THP-1 cell adhesives, and impaired tube-formation capacity in the HCAECs. GroEL1 significantly increased the VCAM-1 mRNA stability and cytosolic AU-binding factor 1 (AUF1) level. Overexpression of the p37AUF1 significantly increased VCAM-1 gene expression in GroEL1-induced bovine aortic endothelial cells (BAECs). GroEL1 prolonged the stability of VCAM-1 mRNA by increasing both p37AUF1 and the regulation of the 5′ untranslated region (UTR) of the VCAM-1 mRNA in BAECs. In hypercholesterolemic rabbits, GroEL1 administration enhanced fatty-streak and macrophage infiltration in atherosclerotic lesions, which may be mediated by elevated VCAM-1 expression. In conclusion, GroEL1 induces VCAM-1 expression by p37AUF1 in endothelial cells and enhances atherogenesis in hypercholesterolemic rabbits.
Collapse
Affiliation(s)
- Chun-Yao Huang
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Research Center For Biomedical Implants and Microsurgery Devices, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
| | - Chun-Ming Shih
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
| | - Nai-Wen Tsao
- Division of Cardiovascular Surgery, Department of Surgery, Taipei Medical University Hospital, Taipei, Taiwan
| | - Yung-Hsiang Chen
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan
| | - Chi-Yuan Li
- Graduate Institute of Clinical Medical Sciences, China Medical University and Department of Anesthesiology, China Medical University Hospital, Taichung, Taiwan
| | - Yu-Jia Chang
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Nen-Chung Chang
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
- Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Keng-Liang Ou
- Research Center For Biomedical Implants and Microsurgery Devices, Taipei Medical University, Taipei, Taiwan
| | - Cheng-Yen Lin
- Department of Computer Science and Information Management, Hung Kuang University, Taichung, Taiwan
| | - Yi-Wen Lin
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
- Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Chih-Hao Nien
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
- Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Feng-Yen Lin
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
- Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
- * E-mail:
| |
Collapse
|
26
|
Roggli E, Gattesco S, Pautz A, Regazzi R. Involvement of the RNA-binding protein ARE/poly(U)-binding factor 1 (AUF1) in the cytotoxic effects of proinflammatory cytokines on pancreatic beta cells. Diabetologia 2012; 55:1699-708. [PMID: 22159912 DOI: 10.1007/s00125-011-2399-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 11/07/2011] [Indexed: 01/01/2023]
Abstract
AIMS/HYPOTHESIS Chronic exposure of pancreatic beta cells to proinflammatory cytokines leads to impaired insulin secretion and apoptosis. ARE/poly(U)-binding factor 1 (AUF1) belongs to a protein family that controls mRNA stability and translation by associating with adenosine- and uridine-rich regions of target messengers. We investigated the involvement of AUF1 in cytokine-induced beta cell dysfunction. METHODS Production and subcellular distribution of AUF1 isoforms were analysed by western blotting. To test for their role in the control of beta cell functions, each isoform was overproduced individually in insulin-secreting cells. The contribution to cytokine-mediated beta cell dysfunction was evaluated by preventing the production of AUF1 isoforms by RNA interference. The effect of AUF1 on the production of potential targets was assessed by western blotting. RESULTS MIN6 cells and human pancreatic islets were found to produce four AUF1 isoforms (p42>p45>p37>p40). AUF1 isoforms were mainly localised in the nucleus but were partially translocated to the cytoplasm upon exposure of beta cells to cytokines and activation of the ERK pathway. Overproduction of AUF1 did not affect glucose-induced insulin secretion but promoted apoptosis. This effect was associated with a decrease in the production of the anti-apoptotic proteins, B cell leukaemia/lymphoma 2 (BCL2) and myeloid cell leukaemia sequence 1 (MCL1). Silencing of AUF1 isoforms restored the levels of the anti-apoptotic proteins, attenuated the activation of the nuclear factor-κB (NFκB) pathway, and protected the beta cells from cytokine-induced apoptosis. CONCLUSIONS/INTERPRETATION Our findings point to a contribution of AUF1 to the deleterious effects of cytokines on beta cell functions and suggest a role for this RNA-binding protein in the early phases of type 1 diabetes.
Collapse
Affiliation(s)
- E Roggli
- Department of Cell Biology and Morphology, Faculty of Biology and Medicine, University of Lausanne, Rue du Bugnon 9, CH-1005 Lausanne, Switzerland
| | | | | | | |
Collapse
|
27
|
Abstract
Type 1 diabetes is a chronic autoimmune disease involving the progressive loss of beta cell mass. Cytokines released by immune cells are early contributors to beta cell apoptosis. Thus, an understanding of the signal transduction mechanisms induced by cytokines in beta cells is necessary for the rational design of novel therapies to prevent or to cure this disease. Cytokine-mediated beta cell apoptosis is a complex phenomenon that includes activation of the transcription factors signal transducer and activator of transcription 1 and nuclear factor κB (NFκB), c-Jun N-terminal kinase, endoplasmic reticulum (ER) stress and the intrinsic mitochondrial apoptotic pathway. NFκB has both a pro-inflammatory and a pro-apoptotic role in beta cells. One of the mechanisms by which NFκB contributes to beta cell apoptosis is via activation of ER stress. The role for ER stress in beta cell apoptosis is not completely clarified but involves production of C/EBP homologous protein and activation of the intrinsic mitochondrial apoptotic pathway. In this issue of Diabetologia, Roggli et al (DOI 10.1007/s00125-011-2399-7) report on a new player in this elaborate response, the RNA-binding protein ARE/poly(U)-binding factor 1. This commentary discusses these findings and their relevance to the field.
Collapse
Affiliation(s)
- E C Vanzela
- Faculty of Medicine, Laboratory of Experimental Medicine, Université Libre de Bruxelles, Route de Lennik 808, Building G-E 5th floor, CP 618, 1070 Brussels, Belgium
| | | |
Collapse
|
28
|
Chung CL, Sheu JR, Chen WL, Chou YC, Hsiao CJ, Hsiao SH, Hsu MJ, Cheng YW, Hsiao G. Histone deacetylase inhibitor m-carboxycinnamic acid bis-hydroxamide attenuates plasminogen activator inhibitor-1 expression in human pleural mesothelial cells. Am J Respir Cell Mol Biol 2012; 46:437-45. [PMID: 22033265 DOI: 10.1165/rcmb.2011-0118oc] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Plasminogen activator inhibitor-1 (PAI-1), primarily up-regulated by transforming growth factor (TGF)-β, is essential in the development of fibrosis. Histone deacetylase (HDAC) was shown to modulate gene expression and fibrogenesis in various tissues. However, the implications of HDAC in terms of PAI-1 expression and pleural fibrosis remain unclear. In this study, we examined the effects of m-carboxycinnamic acid bis-hydroxamide (CBHA), a hybrid-polar HDAC inhibitor, on the TGF-β1-induced expression of PAI-1 in a human pleural mesothelial cell line (MeT-5A). MeT-5A cells were treated with TGF-β1 in the presence or absence of CBHA. We assayed the expression and stability of PAI-1 mRNA and protein, PAI-1 promoter activity, the activation of Smad signaling, the protein-protein interactions of Smads with transcriptional cofactors Sp1 and coactivator p300, and the expression of the mRNA-stabilizing protein nucleolin. The results indicate that CBHA significantly inhibited TGF-β1-induced PAI-1 mRNA and protein expression, and attenuated PAI-1 promoter activity in MeT-5A cells. CBHA abrogated TGF-β1-induced Smad4 nuclear translocation, but not Smad2/3 activation. Furthermore, the association of Smad4 with p300, but not with Sp1, was disrupted by CBHA. Alternatively, CBHA suppressed TGF-β1-induced nucleolin expression, and thereby destabilized PAI-1 mRNA and decreased PAI-1 protein concentrations. These findings suggest that the inhibition of HDAC activity by CBHA may attenuate PAI-1 expression through the modulation of cellular signaling at multiple levels. Given the down-regulating effect of CBHA on PAI-1 expression, HDAC inhibitors should be tested further in animal models as potential therapeutic agents for pleural fibrosis.
Collapse
Affiliation(s)
- Chi-Li Chung
- Division of Pulmonary Medicine, Department of Internal Medicine, Taipei Medical University Hospital, Taiwan
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Tyagi AM, Srivastava K, Kureel J, Kumar A, Raghuvanshi A, Yadav D, Maurya R, Goel A, Singh D. Premature T cell senescence in Ovx mice is inhibited by repletion of estrogen and medicarpin: a possible mechanism for alleviating bone loss. Osteoporos Int 2012; 23:1151-61. [PMID: 21562872 DOI: 10.1007/s00198-011-1650-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 03/10/2011] [Indexed: 01/01/2023]
Abstract
UNLABELLED Presently the relationship between CD28, biological marker of senescence, and ovariectomy is not well understood. We show that ovariectomy leads to CD28 loss on T cells and estrogen (E2) repletion and medicarpin (Med) inhibits this effect. We thus propose that Med/E2 prevents bone loss by delaying premature T cell senescence. INTRODUCTION Estrogen deficiency triggers reproductive aging by accelerating the amplification of TNF-α-producing T cells, thereby leading to bone loss. To date, no study has been carried out to explain the relationship between CD4(+)CD28null T cells and ovariectomy or osteoporosis. We aim to determine the effect of Ovx on CD28 expression on T cells and effects of E2 and medicarpin (a pterocarpan phytoalexin) with proven osteoprotective effect on altered T cell responses. METHODS Adult, female Balb/c mice were taken for the study. The groups were: sham, Ovx, Ovx + Med or E2. Treatments were given daily by oral gavage. At autopsy bone marrow and spleen were flushed out and cells labelled with antibodies for FACS analysis. Serum was collected for ELISA. RESULTS In Ovx mice, Med/E2 at their respective osteoprotective doses resulted in thymus involution and lowered Ovx-induced increase in serum TNF-α level and its mRNA levels in the BM T cells. Med/E2 reduced BM and spleen CD4(+) T cell proliferation and prevented CD28 loss on CD4(+) T cells. Further, Med abrogated TNF-α-induced loss of CD28 expression in the BM T cells. CONCLUSIONS To our knowledge this is the first report to determine the mechanism of CD28 loss on T cells as a result of ovariectomy. Our study demonstrates that Ovx leads to the generation of premature senescent CD4(+)CD28null T cells, an effect inhibited by E2 and Med. We propose that one of the mechanisms by which Med/E2 alleviates Ovx-induced bone loss is by delaying T cell senescence and enhancing CD28 expression.
Collapse
Affiliation(s)
- A M Tyagi
- Division of Endocrinology, Central Drug Research Institute, Council of Scientific and Industrial Research, Chattar Manzil, PO Box 173, Lucknow, India
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Al-Khalaf HH, Colak D, Al-Saif M, Al-Bakheet A, Hendrayani SF, Al-Yousef N, Kaya N, Khabar KS, Aboussekhra A. p16( INK4a) positively regulates cyclin D1 and E2F1 through negative control of AUF1. PLoS One 2011; 6:e21111. [PMID: 21799732 PMCID: PMC3140473 DOI: 10.1371/journal.pone.0021111] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 05/19/2011] [Indexed: 11/23/2022] Open
Abstract
Background The cyclin-D/CDK4,6/p16INK4a/pRB/E2F pathway, a key regulator of the critical G1 to S phase transition of the cell cycle, is universally disrupted in human cancer. However, the precise function of the different members of this pathway and their functional interplay are still not well defined. Methodology/Principal Findings We have shown here that the tumor suppressor p16INK4a protein positively controls the expression of cyclin D1 and E2F1 in both human and mouse cells. p16INK4a stabilizes the mRNAs of the corresponding genes through negative regulation of the mRNA decay-promoting AUF1 protein. Immunoprecipitation of AUF1-associated RNAs followed by RT-PCR indicated that endogenous AUF1 binds to the cyclin D1 and E2F1 mRNAs. Furthermore, AUF1 down-regulation increased the expression levels of these genes, while concurrent silencing of AUF1 and p16INK4a, using specific siRNAs, restored normal expression of both cyclinD1 and E2F1. Besides, we have shown the presence of functional AU-rich elements in the E2F1 3′UTR, which contributed to p16/AUF1-mediated regulation of E2F1 post-transcriptional events in vivo. Importantly, genome-wide gene expression microarray analysis revealed the presence of a large number of genes differentially expressed in a p16INK4a -dependent manner, and several of these genes are also members of the AUF1 and E2F1 regulons. We also present evidence that E2F1 mediates p16-dependent regulation of several pro- and anti-apoptotic proteins, and the consequent induction of spontaneous as well as doxorubicin-induced apoptosis. Conclusion/Significance These findings show that the cyclin-dependent kinase inhibitor p16 INK4a is also a modulator of transcription and apoptosis through controlling the expression of two major transcription regulators, AUF1 and E2F1.
Collapse
Affiliation(s)
- Huda H. Al-Khalaf
- Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Dilek Colak
- Department of Biostatistics, Epidemiology and Scientific Computing, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Maher Al-Saif
- Program in Biomolecular Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Albandary Al-Bakheet
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Siti-Faujiah Hendrayani
- Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Nujoud Al-Yousef
- Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Namik Kaya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Khalid S. Khabar
- Program in Biomolecular Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Abdelilah Aboussekhra
- Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- * E-mail:
| |
Collapse
|
31
|
Abstract
The mRNA-binding protein AUF1 regulates the expression of many key players in cancer including proto-oncogenes, regulators of apoptosis and the cell cycle, and pro-inflammatory cytokines, principally by directing the decay kinetics of their encoded mRNAs. Most studies support an mRNA-destabilizing role for AUF1, although other findings suggest additional functions for this factor. In this review, we explore how changes in AUF1 isoform distribution, subcellular localization, and post-translational protein modifications can influence the metabolism of targeted mRNAs. However, several lines of evidence also support a role for AUF1 in the initiation and/or development of cancer. Many AUF1-targeted transcripts encode products that control pro- and anti-oncogenic processes. Also, overexpression of AUF1 enhances tumorigenesis in murine models, and AUF1 levels are enhanced in some tumors. Finally, signaling cascades that modulate AUF1 function are deregulated in some cancerous tissues. Together, these features suggest that AUF1 may play a prominent role in regulating the expression of many genes that can contribute to tumorigenic phenotypes, and that this post-transcriptional regulatory control point may be subverted by diverse mechanisms in neoplasia.
Collapse
Affiliation(s)
- Beth E. Zucconi
- Department of Biochemistry and Molecular Biology and Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, 108 N. Greene St., Baltimore, MD 21201
| | - Gerald M. Wilson
- Department of Biochemistry and Molecular Biology and Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, 108 N. Greene St., Baltimore, MD 21201
| |
Collapse
|
32
|
Mcgray AJR, Gingerich T, Petrik JJ, Lamarre J. Regulation of thrombospondin-1 expression through AU-rich elements in the 3'UTR of the mRNA. Cell Mol Biol Lett 2011; 16:55-68. [PMID: 21161418 PMCID: PMC6275769 DOI: 10.2478/s11658-010-0037-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Accepted: 11/24/2010] [Indexed: 01/20/2023] Open
Abstract
Thrombospondin-1 (TSP-1) is a matricellular protein that participates in numerous normal and pathological tissue processes and is rapidly modulated by different stimuli. The presence of 8 highly-conserved AU rich elements (AREs) within the 3'-untranslated region (3'UTR) of the TSP-1 mRNA suggests that post-transcriptional regulation is likely to represent one mechanism by which TSP-1 gene expression is regulated. We investigated the roles of these AREs, and proteins which bind to them, in the control of TSP-1 mRNA stability. The endogenous TSP-1 mRNA half-life is approximately 2.0 hours in HEK293 cells. Luciferase reporter mRNAs containing the TSP-1 3'UTR show a similar rate of decay, suggesting that the 3'UTR influences the decay rate. Site-directed mutagenesis of individual and adjacent AREs prolonged reporter mRNA halflife to between 2.2 and 4.4 hours. Mutation of all AREs increased mRNA half life to 8.8 hours, suggesting that all AREs have some effect, but that specific AREs may have key roles in stability regulation. A labeled RNA oligonucleotide derived from the most influential ARE was utilized to purify TSP-1 ARE-binding proteins. The AU-binding protein AUF1 was shown to associate with this motif. These studies reveal that AREs in the 3'UTR control TSP-1 mRNA stability and that the RNA binding protein AUF1 participates in this control. These studies suggest that ARE-dependent control of TSP-1 mRNA stability may represent an important component in the control of TSP-1 gene expression.
Collapse
Affiliation(s)
- Asa J. Robert Mcgray
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1 Canada
| | - Timothy Gingerich
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1 Canada
| | - James J. Petrik
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1 Canada
| | - Jonathan Lamarre
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario N1G 2W1 Canada
| |
Collapse
|
33
|
Abstract
Messenger ribonucleic acid (mRNA) turnover is a major control point in gene expression. In mammals, many mRNAs encoding inflammatory cytokines, oncoproteins, and G-protein-coupled receptors are destabilized by the presence of AU-rich elements (AREs) in their 3'-untranslated regions. Association of ARE-binding proteins (AUBPs) with these mRNAs promotes rapid mRNA degradation. ARE/poly(U)-binding/degradation factor 1 (AUF1), one of the best-characterized AUBPs, binds to many ARE-mRNAs and assembles other factors necessary to recruit the mRNA degradation machinery. These factors include translation initiation factor eIF4G, chaperones hsp27 and hsp70, heat-shock cognate protein hsc70, lactate dehydrogenase, poly(A)-binding protein, and other unidentified proteins. Numerous signaling pathways alter the composition of this AUF1 complex of proteins to effect changes in ARE-mRNA degradation rates. This review briefly describes the roles of mRNA decay in gene expression in general and ARE-mediated decay (AMD) in particular, with a focus on AUF1 and the different modes of regulation that govern AUF1 involvement in AMD.
Collapse
Affiliation(s)
- Frances M. Gratacós
- Department of Molecular Genetics, Microbiology and Immunology, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey, 08854-5635, USA
| | - Gary Brewer
- Department of Molecular Genetics, Microbiology and Immunology, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey, 08854-5635, USA
| |
Collapse
|
34
|
Ing NH. Estradiol up-regulates expression of the A + U-rich binding factor 1 (AUF1) gene in the sheep uterus. J Steroid Biochem Mol Biol 2010; 122:172-9. [PMID: 20621185 DOI: 10.1016/j.jsbmb.2010.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 06/21/2010] [Accepted: 07/03/2010] [Indexed: 10/19/2022]
Abstract
The A+U-rich binding factor 1 (AUF1 or HNRPD) gene produces predominant RNA binding proteins. The AUF1 transcript is alternatively spliced to produce four protein isoforms that stabilize or destabilize hundreds of mRNAs. Previously, we discovered that estradiol (E2) treatment of ovariectomized sheep increased concentrations of AUF1p45 protein which stabilized estrogen receptor alpha (ER) mRNA in the uterus. This study examined E2 regulation of AUF1 mRNAs in the sheep uterus. Northern analysis determined that E2 treatment increased concentrations of total AUF1 mRNAs twofold in endometrial and myometrial tissue compartments. In situ hybridization indicated that the increase was most intense in the glandular epithelium of endometrium. In a well characterized in vitro RNA stability assay, AUF1 3'UTR sequences were much more stable in uterine extracts from E2-treated ewes compared to extracts from control ewes. AUF1 mRNAs with alternative splicing of exons 2 and 7 (in the coding sequence) and exon 9 (in the 3'UTR) were identified. The only effect of E2 treatment on alternative splicing was that it reduced the percentage of AUF1 mRNAs containing exon 9-derived sequences. These data indicate that E2 up-regulates AUF1 and ER genes coordinately by a post-transcriptional mechanism.
Collapse
Affiliation(s)
- Nancy H Ing
- Department of Animal Science, Texas A&M University, 2471 TAMU, College Station, TX 77843-2471, United States
| |
Collapse
|
35
|
Ishimaru D, Zuraw L, Ramalingam S, Sengupta TK, Bandyopadhyay S, Reuben A, Fernandes DJ, Spicer EK. Mechanism of regulation of bcl-2 mRNA by nucleolin and A+U-rich element-binding factor 1 (AUF1). J Biol Chem 2010; 285:27182-27191. [PMID: 20571027 PMCID: PMC2930717 DOI: 10.1074/jbc.m109.098830] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 05/28/2010] [Indexed: 11/06/2022] Open
Abstract
The antiapoptotic Bcl-2 protein is overexpressed in a variety of cancers, particularly leukemias. In some cell types this is the result of enhanced stability of bcl-2 mRNA, which is controlled by elements in its 3'-untranslated region. Nucleolin is one of the proteins that binds to bcl-2 mRNA, thereby increasing its half-life. Here, we examined the site on the bcl-2 3'-untranslated region that is bound by nucleolin as well as the protein binding domains important for bcl-2 mRNA recognition. RNase footprinting and RNA fragment binding assays demonstrated that nucleolin binds to a 40-nucleotide region at the 5' end of the 136-nucleotide bcl-2 AU-rich element (ARE(bcl-2)). The first two RNA binding domains of nucleolin were sufficient for high affinity binding to ARE(bcl-2). In RNA decay assays, ARE(bcl-2) transcripts were protected from exosomal decay by the addition of nucleolin. AUF1 has been shown to recruit the exosome to mRNAs. When MV-4-11 cell extracts were immunodepleted of AUF1, the rate of decay of ARE(bcl-2) transcripts was reduced, indicating that nucleolin and AUF1 have opposing roles in bcl-2 mRNA turnover. When the function of nucleolin in MV-4-11 cells was impaired by treatment with the nucleolin-targeting aptamer AS1411, association of AUF1 with bcl-2 mRNA was increased. This suggests that the degradation of bcl-2 mRNA induced by AS1411 results from both interference with nucleolin protection of bcl-2 mRNA and recruitment of the exosome by AUF1. Based on our findings, we propose a model that illustrates the opposing roles of nucleolin and AUF1 in regulating bcl-2 mRNA stability.
Collapse
Affiliation(s)
- Daniella Ishimaru
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Lisa Zuraw
- Department of Chemistry, The Citadel, Charleston, South Carolina 29409
| | - Sivakumar Ramalingam
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Tapas K Sengupta
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Sumita Bandyopadhyay
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Adrian Reuben
- Division of Gastroenterology and Hepatology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Daniel J Fernandes
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Eleanor K Spicer
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425.
| |
Collapse
|
36
|
Abstract
AUF1/heterogeneous nuclear ribonucleoprotein D is an adenylate-uridylate-rich elements (AREs) -binding protein, which regulates the mRNA stability of many genes related to growth regulation, such as proto-oncogenes, growth factors, cytokines, and cell cycle-regulatory genes. Several studies demonstrated AUF1 involvement in the processes of apoptosis, tumorigenesis, and development by its interactions with ARE-bearing mRNAs. We report here that AUF1 may be involved in thyroid carcinoma progression. Investigations on thyroid tissues revealed that cytoplasmic expression of AUF1 in malignant tissues was increased when compared with benign thyroid tissues. In thyroid carcinoma cell lines, AUF1 was mostly detectable in the nucleus; however, in dividing cells, its increased production was also observed in the cytoplasm. We found AUF1 in complexes with ARE-bearing mRNAs, previously described to be crucial for proliferation and cell cycle of thyroid carcinoma. Total or exon-selective knockdown of AUF1 led to growth inhibition accompanied by induction of cell cycle inhibitors and decreased levels of cell cycle promoters. Our data demonstrate the existence of a complex network between AUF1 and mRNAs encoding proteins related to cell proliferation. AUF1 may control the balance between stabilizing and destabilizing effects, both of which are exerted on cell cycle machinery in thyroid carcinoma. Although we cannot exclude participation of other factors, thyroid carcinoma may recruit cytoplasmic AUF1 to disturb the stability of mRNAs encoding cyclin-dependent kinase inhibitors, leading to uncontrolled growth and progression of tumor cells. Thus, AUF1 may be considered as a new, additional marker for thyroid carcinoma.
Collapse
Affiliation(s)
- Bogusz Trojanowicz
- AG Experimentelle and Chirurgische Onkologie, Universitätsklinik und Poliklinik für Allgemein-, Viszeral- und Gefässchirurgie, Martin-Luther Universität, Magdeburger Strasse 18, 06097 Halle/S, Germany
| | | | | | | | | | | | | |
Collapse
|
37
|
Topisirovic I, Siddiqui N, Borden KLB. The eukaryotic translation initiation factor 4E (eIF4E) and HuR RNA operons collaboratively regulate the expression of survival and proliferative genes. Cell Cycle 2009; 8:960-961. [PMID: 19287207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
|
38
|
Guo X, Gourronc F, Audic Y, Lyons-Levy G, Mitchell T, Hartley RS. ElrA and AUF1 differentially bind cyclin B2 mRNA. Biochem Biophys Res Commun 2008; 377:653-657. [PMID: 18930026 PMCID: PMC2613769 DOI: 10.1016/j.bbrc.2008.10.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Accepted: 10/09/2008] [Indexed: 11/28/2022]
Abstract
In Xenopus embryos, maternal cyclins drive the first 12 cell divisions after which several cyclins are terminally degraded, including cyclin B2. Cyclin B2 disappearance is due to transcription-mediated mRNA deadenylation at the midblastula transition, when transcription initiates and the cell cycle lengthens. To further define the mechanism, we characterized proteins capable of binding cyclin B2 3'UTR. We show that ElrA and AUF1 compete for binding to regions containing cytoplasmic polyadenylation elements (CPEs), with AUF1 binding increasing at the midblastula transition. Deletion of both CPEs abrogates polyadenylation but has no effect on deadenylation or binding of ElrA or AUF1. Overexpression of ElrA or AUF1 does not alter cyclin B2 mRNA stability. These results show that ElrA and AUF1 bind to cyclin B2 mRNA independent of CPEs and function by binding other elements.
Collapse
Affiliation(s)
- Xun Guo
- Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA
| | - Francoise Gourronc
- Microbiology, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA
| | - Yann Audic
- Laboratoire de Genetique du Developpement CNRS-UMR6061, Universite de Rennes I, CS 34317, 35043 Rennes, France
| | - Gillian Lyons-Levy
- Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA
| | - Therese Mitchell
- Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA
| | - Rebecca S Hartley
- Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA.
| |
Collapse
|
39
|
Abdelmohsen K, Kuwano Y, Kim HH, Gorospe M. Posttranscriptional gene regulation by RNA-binding proteins during oxidative stress: implications for cellular senescence. Biol Chem 2008; 389:243-255. [PMID: 18177264 PMCID: PMC8481862 DOI: 10.1515/bc.2008.022] [Citation(s) in RCA: 212] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
To respond adequately to oxidative stress, mammalian cells elicit rapid and tightly controlled changes in gene expression patterns. Besides alterations in the subsets of transcribed genes, two posttranscriptional processes prominently influence the oxidant-triggered gene expression programs: mRNA turnover and translation. Here, we review recent progress in our knowledge of the turnover and translation regulatory (TTR) mRNA-binding proteins (RBPs) that influence gene expression in response to oxidative damage. Specifically, we identify oxidant damage-regulated mRNAs that are targets of TTR-RBPs, we review the oxidant-triggered signaling pathways that govern TTR-RBP function, and we examine emerging evidence that TTR-RBP activity is altered with senescence and aging. Given the potent influence of TTR-RBPs upon oxidant-regulated gene expression profiles, we propose that the senescence-associated changes in TTR-RBPs directly contribute to the impaired responses to oxidant damage that characterize cellular senescence and advancing age.
Collapse
|
40
|
Abstract
A number of highly regulated gene classes are regulated post-transcriptionally at the level of mRNA stability. A central feature in these mRNAs is the presence of A+U-rich elements (ARE) within their 3' UTRs. Two ARE binding proteins, HuR and AUF1, are associated with mRNA stabilization and destabilization, respectively. Previous studies have demonstrated homomultimerization of each protein and the capacity to bind simultaneous or competitively to a single ARE. To investigate this possibility further, cell biological and biophysical approaches were undertaken. Protein-protein interaction was monitored by fluorescence resonance energy transfer (FRET) and by immunocytochemistry in live and fixed cells using fluorescently labeled CFP/YFP fusion proteins of HuR and p37AUF1. Strong nuclear FRET between HuR/HuR and AUF1/AUF1 homodimers as well as HuR/AUF1 heterodimers was observed. Treatment with the MAP kinase activator, anisomycin, which commonly stabilizes ARE-containing mRNAs, caused rapid nuclear to cytoplasmic shuttling of HuR. AUF1 also underwent shuttling, but on a longer time scale. After shuttling, HuR/HuR, AUF1/AUF1, and HuR/AUF1, FRET was also observed in the cytoplasm. In further studies, arsenite rapidly induced the formation of stress granules containing HuR and TIA-1 but not AUF1. The current studies demonstrate that two mRNA binding proteins, HuR and AUF1, are colocalized and are capable of functional interaction in both the nucleus and cytoplasm. FRET-based detection of AUF1/HuR interaction may serve as a basis of opening up new dimensions in delineating the functional interaction of mRNA binding proteins with RNA turnover.
Collapse
Affiliation(s)
- Pamela S David
- Department of Medicine, University of Colorado Health Sciences Center, Denver 80262, USA
| | | | | |
Collapse
|
41
|
Abstract
PURPOSE OF REVIEW This review focuses on the regulation of parathyroid hormone gene expression by dietary-induced hypocalcemia, hypophosphatemia and uremia. Understanding the mechanism by which calcium and phosphate regulate parathyroid hormone gene expression is important for both normal physiology and in pathological states, especially chronic kidney disease. RECENT FINDINGS Calcium and phosphate regulate parathyroid hormone secretion, gene expression and, if prolonged, parathyroid cell proliferation. Chronic kidney disease is characterized by a high serum phosphate level that often leads to secondary hyperparathyroidism. In the rat, regulation of parathyroid hormone gene expression by calcium, phosphate and uremia is posttranscriptional, affecting mRNA stability. Differences in binding of protective trans-acting proteins to a conserved protein-binding cis-acting instability element in the parathyroid hormone mRNA 3'-untranslated region alter parathyroid hormone mRNA stability. Two trans-acting proteins - adenosine-uridine rich binding factor 1 and Up-stream of N-ras- stabilize parathyroid hormone mRNA in vivo and in vitro. Parathyroid hormone mRNA also interacts with mRNA decay-promoting proteins and ribonucleases that lead to parathyroid hormone mRNA degradation. SUMMARY Calcium, phosphate and uremia determine parathyroid hormone mRNA stability through the binding of the protective factors adenosine-uridine rich binding factor 1 and Up-stream of N-ras and the recruitment of a degradation complex that cleaves parathyroid hormone mRNA.
Collapse
Affiliation(s)
- Tally Naveh-Many
- Minerva Center for Calcium and Bone Metabolism, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
| | | |
Collapse
|
42
|
Kakegawa T, Ohuchi N, Hayakawa A, Hirata S, Matsuda M, Kogure K, Kobayashi H, Inoue A, Kaspar RL. Identification of AUF1 as a rapamycin-responsive binding protein to the 5'-terminal oligopyrimidine element of mRNAs. Arch Biochem Biophys 2007; 465:274-81. [PMID: 17603996 DOI: 10.1016/j.abb.2007.06.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 05/30/2007] [Accepted: 06/03/2007] [Indexed: 11/29/2022]
Abstract
In vertebrates, mRNAs containing a 5'-terminal oligopyrimidine (TOP) motif are coordinately post-transcriptionally regulated. Binding of specific proteins to this element has been proposed to downregulate expression of TOP mRNAs at the level of translational initiation. We previously reported that rapamycin induces binding activity to the TOP element of ribosomal protein (r-protein) L32 mRNA. In this study, we adapt DEAE-cellulose/oligo dT-cellulose tandem column chromatography to purify TOP element-binding proteins from bovine submaxillary lymph nodes (SLN). We also show by northwestern blot analysis that two proteins of molecular weight 47kDa (47BP) and 43kDa (43BP) specifically bind to a (32)P-labeled riboprobe containing TOP regulatory element of the r-protein L32. Microsequencing of the purified 47BP revealed an internal sequence of 15 amino acids identical to the consensus sequence of the 2x RBD-Gly family. Western blot analysis of the cytoplasm fractions using an AUF1 antibody revealed that these two proteins are p45 AUF1 and p42 AUF1. Increases of the four isoforms of AUF1 protein were observed in 100,000g supernatant fractions of rapamycin-administered rat SLN. Furthermore, decreases of p45 AUF1 and p42 and/or p40 AUF1 were observed in the polysomal fractions of BJAB cells in which translation of TOP mRNAs was selectively suppressed by rapamycin treatment. Taken together, these results suggest that AUF1 is a TOP mRNA-binding protein that may participate in the translational suppression of TOP mRNAs resulting from rapamycin treatment.
Collapse
Affiliation(s)
- Tomohito Kakegawa
- Faculty of Pharmaceutical Sciences, Josai International University, 1 Gumyo, Togane, Chiba 283-8555, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Liao B, Hu Y, Brewer G. Competitive binding of AUF1 and TIAR to MYC mRNA controls its translation. Nat Struct Mol Biol 2007; 14:511-8. [PMID: 17486099 DOI: 10.1038/nsmb1249] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2006] [Accepted: 04/09/2007] [Indexed: 11/09/2022]
Abstract
(A+U)-rich elements (AREs) within 3' untranslated regions are signals for rapid degradation of messenger RNAs encoding many oncoproteins and cytokines. The ARE-binding protein AUF1 contributes to their degradation. We identified MYC proto-oncogene mRNA as a cellular AUF1 target. Levels of MYC translation and cell proliferation were proportional to AUF1 abundance but inversely proportional to the abundance of the ARE-binding protein TIAR, a MYC translational suppressor. Both AUF1 and TIAR affected MYC translation via the ARE without affecting mRNA abundance. Altering association of one ARE-binding protein with MYC mRNA in vivo reciprocally affected mRNA association with the other protein. Finally, genetic experiments revealed that AUF1 and TIAR control proliferation by a MYC-dependent pathway. Together, these observations suggest a novel regulatory mechanism where tuning the ratios of AUF1 and TIAR bound to MYC mRNA permits dynamic control of MYC translation and cell proliferation.
Collapse
Affiliation(s)
- Baisong Liao
- Department of Molecular Genetics, Microbiology, and Immunology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, New Jersey 08854, USA
| | | | | |
Collapse
|
44
|
Mazan-Mamczarz K, Gartenhaus RB. Post-transcriptional control of the MCT-1-associated protein DENR/DRP by RNA-binding protein AUF1. Cancer Genomics Proteomics 2007; 4:233-9. [PMID: 17878526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023] Open
Abstract
BACKGROUND There is often a poor correlation observed between protein and RNA in eukaryotic systems, supporting the emerging pardigm that many of the abnormalities in a cancer cell's proteome may be achieved by differential recruitment of mRNAs to polysomes referred to as the translational profile. The MCT-1 oncogene product has recently been shown to interact with the cap complex and to modulate the translational profile of cell lines when MCT-1 was highly expressed. The MCT-1 protein modifies mRNA translational profiles through its interaction with DENR/DRP, a protein containing an SUI1 domain involved in recognition of the translation initiation codon. It has been shown previously that the protein levels of DENR/DRP go up in parallel with increasing cell density, however the mechanism(s) underlying this increase is poorly understood at present. The 3'-untranslated region (3'UTR) of DENR/DRP was found to have a high number of uracyl (U)- and adenine (A)-rich sequences (AREs). Many RNA-binding proteins (RBPs) have been shown to recognize and bind to mRNAs that contains AREs generally present in the 3'UTR of mRNAs. RBPs binding to AREs such as AUF1, BRF1, KSRP, and TTP are known to regulate mRNA turnover, while TIAR and TIA-1 influence mRNA translation. MATERIALS AND METHODS We assessed the association of several ARE binding proteins with DENR/DRP mRNA by reverse transcription of the RNA obtained after immunoprecipitation of cell lysates from HEK 293 cells growing at varying levels of cell density. HEK 293 cells were transfected with an AUF1 silencing vector (shRNA), and protein levels of DENR/DRP were analyzed by Western blotting. RESULTS We demonstrated that both HuR and AUF1 bind to discrete regions of DENR/DRP mRNA and that AUF1 silencing increases DENR/DRP protein levels. CONCLUSION Our data established a cell density-dependent interaction of AUF1 protein with DENR/DRP mRNA that modulates DENR/DRP protein levels.
Collapse
Affiliation(s)
- Krystyna Mazan-Mamczarz
- University of Maryland, Marlene and Stewart Greenebaum Cancer Center 9-011 BRB, 655 West Baltimore Street, Baltimore, Maryland 21201, USA
| | | |
Collapse
|
45
|
Nagaoka K, Tanaka T, Imakawa K, Sakai S. Involvement of RNA binding proteins AUF1 in mammary gland differentiation. Exp Cell Res 2007; 313:2937-45. [PMID: 17512931 DOI: 10.1016/j.yexcr.2007.04.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 04/01/2007] [Accepted: 04/16/2007] [Indexed: 11/20/2022]
Abstract
The expression of many genes, such as beta-casein, c-myc, and cyclin D1, is altered by lactogenic hormone stimulation during mammary epithelial cell differentiation. Here, we demonstrate that post-transcriptional regulation plays an important role to establish gene expression required to initiate milk production as well as transcriptional control. AUF1 protein, a member of the AU-rich element (ARE)-binding protein family, plays a role in ARE-mRNA turnover by regulating mRNA stability and/or translational control. Cytoplasmic localization of AUF1 protein is critically linked to function. We show that as the mammary gland differentiates, AUF1 protein moves from the cytoplasm to the nucleus. Moreover, in mammary gland epithelial cells (HC11), stimulation by lactogenic hormone decreased cytoplasmic and increased nuclear AUF1 levels. Direct binding of AUF1 protein was observed on c-myc mRNA, but not beta-casein or cyclin D1 mRNA. AUF1 downregulation in HC11 cells increased the expression of beta-casein mRNA and decreased the expression of c-myc mRNA by lactogenic hormone. Conversely, overexpression of AUF1 inhibited these effects of lactogenic hormone stimulation in HC11 cells. These results suggest that AUF1 participates in mammary gland differentiation processes under the control of lactogenic hormone signals.
Collapse
Affiliation(s)
- Kentaro Nagaoka
- Laboratory of Animal Breeding, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Tokyo, Japan.
| | | | | | | |
Collapse
|
46
|
Matsui H, Asou H, Inaba T. Cytokines direct the regulation of Bim mRNA stability by heat-shock cognate protein 70. Mol Cell 2007; 25:99-112. [PMID: 17218274 DOI: 10.1016/j.molcel.2006.12.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Revised: 11/05/2006] [Accepted: 12/12/2006] [Indexed: 10/23/2022]
Abstract
Previous gene-targeting studies indicated that Bim, a BH3-only death activator, regulates total blood cell number. Cytokines contribute to this process by negatively regulating steady-state levels of Bim mRNA. Here we present a molecular mechanism for cytokine-mediated posttranscriptional regulation of Bim mRNA by heat-shock cognate protein 70 (Hsc70), which binds to AU-rich elements (AREs) in the 3'-untranslated region of specific mRNAs and enhances their stability. The RNA binding potential of Hsc70 is regulated by cochaperones including Bag-4 (also SODD), CHIP, Hip, and Hsp40. Cytokines regulate the expression or function of these cochaperones by activating Ras pathways. Thus, exposure of cells to cytokines ultimately leads to destabilization of Bim mRNA and promotion of cell survival. This unanticipated role of a chaperone/cochaperone complex in mRNA stability appears to be critical for hematopoiesis and leukemogenesis.
Collapse
Affiliation(s)
- Hirotaka Matsui
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553, Japan
| | | | | |
Collapse
|
47
|
Katsanou V, Dimitriou M, Kontoyiannis DL. Post-transcriptional Regulators in Inflammation: Exploring New Avenues in Biological Therapeutics. Immunotherapy in 2020 2007:37-57. [PMID: 17824180 DOI: 10.1007/2789_2007_038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The biosynthesis of inflammatory mediators relies on controlling the biogenesis and utilization of their corresponding messenger RNAs (mRNAs). These latter "utilization steps" encompass post-transcriptional mechanisms that gradually and variably impose a series of flexible-rate limiting controls to modify the abundance of an mRNA and the rate of its translation to protein in response to environmental signals. Mechanistically, post-transcriptional machines comprise networks of RNA binding proteins (RBPs), which recognize, passively or inducibly, secondary or tertiary ribonucleotide structures located on their target RNAs. The outcome of these interactions is the stringent control of mRNA maturation, localization, turnover and translation. It is conceivable that if these post-transcriptional interactions fail, they may perturb cellular re-sponses to provide the impetus for chronic disease. Such is the case of the signal-responsive mechanisms affecting inflammatory mRNAs containing the AU-rich family of elements (AREs), which are recognized by a specific subset of RBPs. Intense research in this area has yielded important insight on the specific signals and mechanisms affecting the utilization of ARE-containing mRNAs. Here, we indicate briefly the inflammatory relevance of ARE-related mechanisms to highlight their importance in pathophysiology and their potential in the development of future biological therapies.
Collapse
Affiliation(s)
- V Katsanou
- BSRC Alexander Fleming, Institute of Immunology, 34 A1. Fleming Str, 16672 Vari, Greece
| | | | | |
Collapse
|
48
|
Torrisani J, Unterberger A, Tendulkar SR, Shikimi K, Szyf M. AUF1 cell cycle variations define genomic DNA methylation by regulation of DNMT1 mRNA stability. Mol Cell Biol 2007; 27:395-410. [PMID: 17030625 PMCID: PMC1800664 DOI: 10.1128/mcb.01236-06] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2006] [Revised: 07/28/2006] [Accepted: 09/22/2006] [Indexed: 01/26/2023] Open
Abstract
DNA methylation is a major determinant of epigenetic inheritance. DNA methyltransferase 1 (DNMT1) is the enzyme responsible for the maintenance of DNA methylation patterns during cell division, and deregulated expression of DNMT1 leads to cellular transformation. We show herein that AU-rich element/poly(U)-binding/degradation factor 1 (AUF1)/heterogeneous nuclear ribonucleoprotein D interacts with an AU-rich conserved element in the 3' untranslated region of the DNMT1 mRNA and targets it for destabilization by the exosome. AUF1 protein levels are regulated by the cell cycle by the proteasome, resulting in cell cycle-specific destabilization of DNMT1 mRNA. AUF1 knock down leads to increased DNMT1 expression and modifications of cell cycle kinetics, increased DNA methyltransferase activity, and genome hypermethylation. Concurrent AUF1 and DNMT1 knock down abolishes this effect, suggesting that the effects of AUF1 knock down on the cell cycle are mediated at least in part by DNMT1. In this study, we demonstrate a link between AUF1, the RNA degradation machinery, and maintenance of the epigenetic integrity of the cell.
Collapse
Affiliation(s)
- Jerome Torrisani
- Department of Pharmacology and Therapeutics, McGill University, 3655 Sir William Osler Promenade, Montreal, Quebec H3G 1Y6, Canada
| | | | | | | | | |
Collapse
|
49
|
Sagliocco F, Laloo B, Cosson B, Laborde L, Castroviejo M, Rosenbaum J, Ripoche J, Grosset C. The ARE-associated factor AUF1 binds poly(A) in vitro in competition with PABP. Biochem J 2006; 400:337-47. [PMID: 16834569 PMCID: PMC1652824 DOI: 10.1042/bj20060328] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The ARE (AU-rich element) is a post-transcriptional element controlling both mRNA turnover and translation initiation by primarily inducing poly(A) tail shortening. The mechanisms by which the ARE-associated proteins induce deadenylation are still obscure. One possibility among others would be that an ARE-ARE-BP (ARE-binding protein) complex intervenes in the PABP [poly(A)-binding protein]-poly(A) tail association and facilitates poly(A) tail accessibility to deadenylases. Here, we show by several experimental approaches that AUF1 (AU-rich element RNA-binding protein 1)/hnRNP (heterogeneous nuclear ribonucleoprotein) D, an mRNA-destabilizing ARE-BP, can bind poly(A) sequence in vitro. First, endogenous AUF1 proteins from HeLa cells specifically bound poly(A), independently of PABP. Secondly, using polyadenylated RNA probes, we showed that (i) the four recombinant AUF1 isoforms bind poly(A) as efficiently as PABP, (ii) the AUF1 binding to poly(A) does not change when the polyadenylated probe contains the GM-CSF (granulocyte/macrophage-colony stimulating factor) ARE, suggesting that, in vitro, the AUF1-poly(A) association was independent of the ARE sequence itself. In vitro, the binding of AUF1 isoforms to poly(A) displayed oligomeric and co-operative properties and AUF1 efficiently displaced PABP from the poly(A). Finally, the AUF1 molar concentration in HeLa cytoplasm was only 2-fold lower than that of PABP, whereas in the nucleus, its molar concentration was similar to that of PABP. These in vitro results suggest that, in vivo, AUF1 could compete with PABP for the binding to poly(A). Altogether, our results may suggest a role for AUF1 in controlling PABP-poly(A) tail association.
Collapse
Affiliation(s)
- Francis Sagliocco
- *INSERM, E362, Bordeaux, F-33076 France; Université Victor Segalen Bordeaux 2, Bordeaux, F-33076 France
- †IFR66, Bordeaux, F-33076 France
| | - Benoît Laloo
- *INSERM, E362, Bordeaux, F-33076 France; Université Victor Segalen Bordeaux 2, Bordeaux, F-33076 France
- †IFR66, Bordeaux, F-33076 France
| | - Bertrand Cosson
- ‡CNRS, UMR 6061, Rennes F-35043, France; Université Rennes I, Rennes, F-35043 France
| | - Laurence Laborde
- *INSERM, E362, Bordeaux, F-33076 France; Université Victor Segalen Bordeaux 2, Bordeaux, F-33076 France
- †IFR66, Bordeaux, F-33076 France
| | - Michel Castroviejo
- †IFR66, Bordeaux, F-33076 France
- §CNRS, UMR 5097, Bordeaux, F-33076 France; Université Victor Segalen Bordeaux 2, Bordeaux, F-33076 France
| | - Jean Rosenbaum
- *INSERM, E362, Bordeaux, F-33076 France; Université Victor Segalen Bordeaux 2, Bordeaux, F-33076 France
- †IFR66, Bordeaux, F-33076 France
| | - Jean Ripoche
- *INSERM, E362, Bordeaux, F-33076 France; Université Victor Segalen Bordeaux 2, Bordeaux, F-33076 France
- †IFR66, Bordeaux, F-33076 France
| | - Christophe Grosset
- *INSERM, E362, Bordeaux, F-33076 France; Université Victor Segalen Bordeaux 2, Bordeaux, F-33076 France
- †IFR66, Bordeaux, F-33076 France
- To whom correspondence should be addressed (email )
| |
Collapse
|
50
|
Abstract
Excessive production of proinflammatory cytokines, particularly tumor necrosis factor-alpha (TNFalpha) and interleukin-1beta (IL-1beta), plays a critical role in septic shock induced by bacterial endotoxin (endotoxemia). Precise control of cytokine expression depends on rapid degradation of cytokine mRNAs, mediated by an AU-rich element (ARE) in the 3' noncoding region and by interacting ARE-binding proteins, which control the systemic inflammatory response. To understand the function of the ARE-binding protein AUF1, we developed an AUF1 knockout mouse. We show that AUF1 normally functions to protect against the lethal progression of endotoxemia. Upon endotoxin challenge, AUF1 knockout mice display symptoms of severe endotoxic shock, including vascular hemorrhage, intravascular coagulation, and high mortality, resulting from overproduction of TNFalpha and IL-1beta. Overexpression of these two cytokines is specific, and shown to result from an inability to rapidly degrade these mRNAs in macrophages following induction. Neutralizing antibodies to TNFalpha and IL-1beta protect AUF1 knockout mice against lethal endotoxic shock. These and other data describe a novel post-transcriptional mechanism whereby AUF1 acts as a crucial attenuator of the inflammatory response, promoting the rapid decay of selective proinflammatory cytokine mRNAs following endotoxin activation. Defects in the AUF1 post-transcriptionally controlled pathway may be involved in human inflammatory disease.
Collapse
Affiliation(s)
- Jin-Yu Lu
- Department of Microbiology, New York University School of Medicine, New York, New York 10016, USA
| | | | | |
Collapse
|