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Shin HC, Bochkov YA, Kim K, Gern JE, Jarjour NN, Esnault S. A motif in the 5'untranslated region of messenger RNAs regulates protein synthesis in a S6 kinase-dependent manner. Adv Biol Regul 2023; 89:100975. [PMID: 37302177 PMCID: PMC10735251 DOI: 10.1016/j.jbior.2023.100975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 06/05/2023] [Indexed: 06/13/2023]
Abstract
The 5' untranslated regions (UTRs) in messenger RNAs (mRNAs) play an important role in the regulation of protein synthesis. We had previously identified a group of mRNAs that includes human semaphorin 7A (SEMA7A) whose translation is upregulated by the Erk/p90S6K pathway in human eosinophils, with a potential negative impact in asthma and airway inflammation. In the current study, we aimed to find a common 5'UTR regulatory cis-element, and determine its impact on protein synthesis. We identified a common and conserved 5'UTR motif GGCTG-[(C/G)T(C/G)]n-GCC that was present in this group of mRNAs. Mutations of the first two GG bases in this motif in SEMA7A 5'UTR led to a complete loss of S6K activity dependence for maximal translation. In conclusion, the newly identified 5'UTR motif present in SEMA7A has a critical role in regulating S6K-dependent protein synthesis.
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Affiliation(s)
- Hyun-Chul Shin
- Department of Chemistry Education, Korea National University of Education, Cheongju-si, Chungcheonbuk-do, Republic of Korea
| | - Yury A Bochkov
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Kangsan Kim
- Department of Chemistry Education, Korea National University of Education, Cheongju-si, Chungcheonbuk-do, Republic of Korea
| | - James E Gern
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA; Department of Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Nizar N Jarjour
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Stephane Esnault
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA.
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2
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Suzuki Y, Yamada T, Suzuki MG. In Vitro Comparison of Sex-Specific Splicing Efficiencies of fem Pre-mRNA under Monoallelic and Heteroallelic Conditions of csd, a Master Sex-Determining Gene in the Honeybee. J Dev Biol 2023; 11:jdb11010010. [PMID: 36976099 PMCID: PMC10057164 DOI: 10.3390/jdb11010010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 03/05/2023] [Accepted: 03/08/2023] [Indexed: 03/12/2023] Open
Abstract
The sexual fate of honeybees is determined by the complementary sex determination (CSD) model: heterozygosity at a single locus (the CSD locus) determines femaleness, while hemizygosity or homozygosity at the CSD locus determines maleness. The csd gene encodes a splicing factor that regulates sex-specific splicing of the downstream target gene feminizer (fem), which is required for femaleness. The female mode of fem splicing occurs only when csd is present in the heteroallelic condition. To gain insights into how Csd proteins are only activated under the heterozygous allelic composition, we developed an in vitro assay system to evaluate the activity of Csd proteins. Consistent with the CSD model, the co-expression of two csd alleles, both of which lack splicing activity under the single-allele condition, restored the splicing activity that governs the female mode of fem splicing. RNA immunoprecipitation quantitative PCR analyses demonstrated that the CSD protein was specifically enriched in several exonic regions in the fem pre-mRNA, and enrichment in exons 3a and 5 was significantly greater under the heterozygous allelic composition than the single-allelic condition. However, in most cases csd expression under the monoallelic condition was capable of inducing the female mode of fem splicing contrary to the conventional CSD model. In contrast, repression of the male mode of fem splicing was predominant under heteroallelic conditions. These results were reproduced by real-time PCR of endogenous fem expression in female and male pupae. These findings strongly suggest that the heteroallelic composition of csd may be more important for the repression of the male splicing mode than for the induction of the female splicing mode of the fem gene.
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Affiliation(s)
- Yukihiro Suzuki
- INTERSTELLAR Inc., 301 Unico A, 3-4 Nisshin-cho, Kawasaki-ku, Kawasaki 210-0024, Kanagawa, Japan
| | - Takafumi Yamada
- YAMADA-KUN’S Bee Farm, 95 Ochino, Mugegawa, Seki 501-2602, Gifu, Japan
| | - Masataka G. Suzuki
- Division of Biological Sciences, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 302 Bioscience-Bldg, 5-1-5 Kashiwanoha, Kashiwa 277-8562, Chiba, Japan
- Correspondence: ; Tel.: +81-4-7136-3694
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3
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The effects of female sexual hormones on the endothelial glycocalyx. CURRENT TOPICS IN MEMBRANES 2023; 91:89-137. [PMID: 37080682 DOI: 10.1016/bs.ctm.2023.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The glycocalyx is a layer composed of carbohydrate side chains bound to core proteins that lines the vascular endothelium. The integrity of the glycocalyx is essential for endothelial cells' performance and vascular homeostasis. The neuroendocrine and immune systems influence the composition, maintenance, activity and degradation of the endothelial glycocalyx. The female organism has unique characteristics, and estrogen and progesterone, the main female hormones are essential to the development and physiology of the reproductive system and to the ability to develop a fetus. Female sex hormones also exert a wide variety of effects on other organs, including the vascular endothelium. They upregulate nitric oxide synthase expression and activity, decrease oxidative stress, increase vasodilation, and protect from vascular injury. This review will discuss how female hormones and pregnancy, which prompts to high levels of estrogen and progesterone, modulate the endothelial glycocalyx. Diseases prevalent in women that alter the glycocalyx, and therapeutic forms to prevent glycocalyx degradation and potential treatments that can reconstitute its structure and function will also be discussed.
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4
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Hu Antigen R (HuR) Protein Structure, Function and Regulation in Hepatobiliary Tumors. Cancers (Basel) 2022; 14:cancers14112666. [PMID: 35681645 PMCID: PMC9179498 DOI: 10.3390/cancers14112666] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/19/2022] [Accepted: 05/23/2022] [Indexed: 12/10/2022] Open
Abstract
Simple Summary Hepatobiliary tumors are a group of primary malignancies encompassing the liver, the intra- and extra-hepatic biliary tracts, and the gall bladder. Within the liver, hepatocellular carcinoma (HCC) is the most common type of primary cancer, which is, also, representing the third-most recurrent cause of cancer-associated death and the sixth-most prevalent type of tumor worldwide, nowadays. Although less frequent, cholangiocarcinoma (CCA) is, currently, a fatal cancer with limited therapeutic options. Here, we review the regulatory role of Hu antigen R (HuR), a ubiquitous member of the ELAV/Hu family of RNA-binding proteins (RBPs), in the pathogenesis, progression, and treatment of HCC and CCA. Overall, HuR is proposed as a valuable diagnostic and prognostic marker, as well as a therapeutic target in hepatobiliary cancers. Therefore, novel therapeutic approaches that can selectively modulate HuR function appear to be highly attractive for the clinical management of these types of tumors. Abstract Hu antigen R (HuR) is a 36-kDa ubiquitous member of the ELAV/Hu family of RNA-binding proteins (RBPs), which plays an important role as a post-transcriptional regulator of specific RNAs under physiological and pathological conditions, including cancer. Herein, we review HuR protein structure, function, and its regulation, as well as its implications in the pathogenesis, progression, and treatment of hepatobiliary cancers. In particular, we focus on hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), tumors where the increased cytoplasmic localization of HuR and activity are proposed, as valuable diagnostic and prognostic markers. An overview of the main regulatory axes involving HuR, which are associated with cell proliferation, invasion, metastasis, apoptosis, and autophagy in HCC, is provided. These include the transcriptional, post-transcriptional, and post-translational modulators of HuR function, in addition to HuR target transcripts. Finally, whereas studies addressing the relevance of targeting HuR in CCA are limited, in the past few years, HuR has emerged as a potential therapeutic target in HCC. In fact, the therapeutic efficacy of some pharmacological inhibitors of HuR has been evaluated, in early experimental models of HCC. We, further, discuss the major findings and future perspectives of therapeutic approaches that specifically block HuR interactions, either with post-translational modifiers or cognate transcripts in hepatobiliary cancers.
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Y-Box Binding Proteins in mRNP Assembly, Translation, and Stability Control. Biomolecules 2020; 10:biom10040591. [PMID: 32290447 PMCID: PMC7226217 DOI: 10.3390/biom10040591] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/06/2020] [Accepted: 04/10/2020] [Indexed: 12/12/2022] Open
Abstract
Y-box binding proteins (YB proteins) are DNA/RNA-binding proteins belonging to a large family of proteins with the cold shock domain. Functionally, these proteins are known to be the most diverse, although the literature hardly offers any molecular mechanisms governing their activities in the cell, tissue, or the whole organism. This review describes the involvement of YB proteins in RNA-dependent processes, such as mRNA packaging into mRNPs, mRNA translation, and mRNA stabilization. In addition, recent data on the structural peculiarities of YB proteins underlying their interactions with nucleic acids are discussed.
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Schultz CW, Preet R, Dhir T, Dixon DA, Brody JR. Understanding and targeting the disease-related RNA binding protein human antigen R (HuR). WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 11:e1581. [PMID: 31970930 DOI: 10.1002/wrna.1581] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/02/2019] [Accepted: 12/07/2019] [Indexed: 02/06/2023]
Abstract
Altered gene expression is a characteristic feature of many disease states such as tumorigenesis, and in most cancers, it facilitates cancer cell survival and adaptation. Alterations in global gene expression are strongly impacted by post-transcriptional gene regulation. The RNA binding protein (RBP) HuR (ELAVL1) is an established regulator of post-transcriptional gene regulation and is overexpressed in most human cancers. In many cancerous settings, HuR is not only overexpressed, but it is "overactive" as denoted by increased subcellular localization within the cytoplasm. This dysregulation of HuR expression and cytoplasmic localization allows HuR to stabilize and increase the translation of various prosurvival messenger RNA (mRNAs) involved in the pathogenesis of numerous cancers and various diseases. Based on almost 20 years of work, HuR is now recognized as a therapeutic target. Herein, we will review the role HuR plays in the pathophysiology of different diseases and ongoing therapeutic strategies to target HuR. We will focus on three ongoing-targeted strategies: (1) inhibiting HuR's translocation from the nucleus to the cytoplasm; (2) inhibiting the ability of HuR to bind target RNA; and (3) silencing HuR expression levels. In an oncologic setting, HuR has been demonstrated to be critical for a cancer cell's ability to survive a variety of cancer relevant stressors (including drugs and elements of the tumor microenvironment) and targeting this protein has been shown to sensitize cancer cells further to insult. We strongly believe that targeting HuR could be a powerful therapeutic target to treat different diseases, particularly cancer, in the near future. This article is categorized under: RNA in Disease and Development > RNA in Disease NRA Turnover and Surveillance > Regulation of RNA Stability Translation > Translation Regulation.
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Affiliation(s)
- Christopher W Schultz
- Department of Surgery, Jefferson Pancreas, Biliary and Related Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Ranjan Preet
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas
| | - Teena Dhir
- Department of Surgery, Jefferson Pancreas, Biliary and Related Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Dan A Dixon
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas
| | - Jonathan R Brody
- Department of Surgery, Jefferson Pancreas, Biliary and Related Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania
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7
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Park YS, Lee JE, Park JI, Myung CH, Lim YH, Park CK, Hwang JS. Inhibitory mechanism of ginsenoside Rh3 on granulocyte-macrophage colony-stimulating factor expression in UV-B-irradiated murine SP-1 keratinocytes. J Ginseng Res 2018; 44:274-281. [PMID: 32148409 PMCID: PMC7031754 DOI: 10.1016/j.jgr.2018.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 11/20/2018] [Accepted: 12/18/2018] [Indexed: 12/16/2022] Open
Abstract
Background Ultraviolet (UV) goes through the epidermis and promotes release of inflammatory cytokines in keratinocytes. Granulocyte–macrophage colony-stimulating factor (GM-CSF), one of the keratinocyte-derived cytokines, regulates proliferation and differentiation of melanocytes. Extracellular signal–regulated kinase (ERK1/2) and protein kinase C (PKC) signaling pathways regulate expression of GM-CSF. Based on these results, we found that ginsenoside Rh3 prevented GM-CSF production and release in UV-B–exposed SP-1 keratinocytes and that this inhibitory effect resulted from the reduction of PKCδ and ERK phosphorylation. Methods We investigated the mechanism by which ginsenoside Rh3 from Panax ginseng inhibited GM-CSF release from UV-B–irradiated keratinocytes. Results Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) or UV-B induced release of GM-CSF in the SP-1 keratinocytes. To elucidate whether the change in GM-CSF expression could be related to PKC signaling, the cells were pretreated with H7, an inhibitor of PKC, and irradiated with UV-B. GM-CSF was decreased by H7 in a dose-dependent manner. When we analyzed which ginsenosides repressed GM-CSF expression among 15 ginsenosides, ginsenoside Rh3 showed the largest decline to 40% of GM-CSF expression in enzyme-linked immunosorbent assay. Western blot analysis showed that TPA enhanced the phosphorylation of PKCδ and ERK in the keratinocytes. When we examined the effect of ginsenoside Rh3, we identified that ginsenoside Rh3 inhibited the TPA-induced phosphorylation levels of PKCδ and ERK. Conclusion In summary, we found that ginsenoside Rh3 impeded UV-B–induced GM-CSF production through repression of PKCδ and ERK phosphorylation in SP-1 keratinocytes.
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Affiliation(s)
- Young Sun Park
- Department of Genetic Engineering & Graduate School of Biotechnology, Kyung Hee University, Yongin, Republic of Korea
| | - Ji Eun Lee
- Department of Genetic Engineering & Graduate School of Biotechnology, Kyung Hee University, Yongin, Republic of Korea
| | - Jong Il Park
- Department of Genetic Engineering & Graduate School of Biotechnology, Kyung Hee University, Yongin, Republic of Korea
| | - Cheol Hwan Myung
- Department of Genetic Engineering & Graduate School of Biotechnology, Kyung Hee University, Yongin, Republic of Korea
| | - Young-Ho Lim
- KGC R&D Headquarters, Daejeon, Republic of Korea
| | | | - Jae Sung Hwang
- Department of Genetic Engineering & Graduate School of Biotechnology, Kyung Hee University, Yongin, Republic of Korea
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8
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Lindquist JA, Mertens PR. Cold shock proteins: from cellular mechanisms to pathophysiology and disease. Cell Commun Signal 2018; 16:63. [PMID: 30257675 PMCID: PMC6158828 DOI: 10.1186/s12964-018-0274-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 09/13/2018] [Indexed: 12/21/2022] Open
Abstract
Cold shock proteins are multifunctional RNA/DNA binding proteins, characterized by the presence of one or more cold shock domains. In humans, the best characterized members of this family are denoted Y-box binding proteins, such as Y-box binding protein-1 (YB-1). Biological activities range from the regulation of transcription, splicing and translation, to the orchestration of exosomal RNA content. Indeed, the secretion of YB-1 from cells via exosomes has opened the door to further potent activities. Evidence links a skewed cold shock protein expression pattern with cancer and inflammatory diseases. In this review the evidence for a causative involvement of cold shock proteins in disease development and progression is summarized. Furthermore, the potential application of cold shock proteins for diagnostics and as targets for therapy is elucidated.
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Affiliation(s)
- Jonathan A Lindquist
- Clinic for Nephrology and Hypertension, Diabetology and Endocrinology, Otto-von-Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Peter R Mertens
- Clinic for Nephrology and Hypertension, Diabetology and Endocrinology, Otto-von-Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany.
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Rao GK, Wong A, Collinge M, Sarhan J, Yarovinsky TO, Ramgolam VS, Gaestel M, Pardi R, Bender JR. T cell LFA-1-induced proinflammatory mRNA stabilization is mediated by the p38 pathway kinase MK2 in a process regulated by hnRNPs C, H1 and K. PLoS One 2018; 13:e0201103. [PMID: 30048492 PMCID: PMC6065199 DOI: 10.1371/journal.pone.0201103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 07/09/2018] [Indexed: 11/18/2022] Open
Abstract
Activation of the β2 integrin lymphocyte function-associated antigen-1 (LFA-1) in T cells induces stabilization of proinflammatory AU-rich element (ARE)-bearing mRNAs, by triggering the nuclear-to-cytoplasmic translocation of the mRNA-binding and -stabilizing protein HuR. However, the mechanism by which LFA-1 engagement controls HuR localization is not known. Here, we identify and characterize four key regulators of LFA-1-induced changes in HuR activity: the p38 pathway kinase MK2 and the constitutive nuclear proteins hnRNPs C, H1 and K. LFA-1 engagement results in rapid, sequential activation of p38 and MK2. Post-LFA-1 activation, MK2 inducibly associates with both hnRNPC and HuR, resulting in the dissociation of HuR from hnRNPs C, H1 and K. Freed from the three hnRNPs, HuR translocates from the nucleus to the cytoplasm, and mediates the stabilization of labile cytokine transcripts. Our results suggest that the modulation of T cell cytokine mRNA half-life is an intricate process that is negatively regulated by hnRNPs C, H1 and K and requires MK2 as a critical activator.
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Affiliation(s)
- Gautham K. Rao
- Department of Internal Medicine, Section of Cardiovascular Medicine,
Cardiovascular Research Center, Yale University School of Medicine, New Haven,
Connecticut, United States of America
- Department of Immunobiology, Yale University School of Medicine, New
Haven, Connecticut, United States of America
- Raymond and Beverly Sackler Foundation Cardiovascular Laboratory, New
Haven, Connecticut, United States of America
| | - Albert Wong
- Raymond and Beverly Sackler Foundation Cardiovascular Laboratory, New
Haven, Connecticut, United States of America
- Department of Cell Biology, Yale University School of Medicine, New
Haven, Connecticut, United States of America
| | - Mark Collinge
- Department of Internal Medicine, Section of Cardiovascular Medicine,
Cardiovascular Research Center, Yale University School of Medicine, New Haven,
Connecticut, United States of America
- Department of Immunobiology, Yale University School of Medicine, New
Haven, Connecticut, United States of America
- Raymond and Beverly Sackler Foundation Cardiovascular Laboratory, New
Haven, Connecticut, United States of America
| | - Joseph Sarhan
- Department of Internal Medicine, Section of Cardiovascular Medicine,
Cardiovascular Research Center, Yale University School of Medicine, New Haven,
Connecticut, United States of America
- Department of Immunobiology, Yale University School of Medicine, New
Haven, Connecticut, United States of America
- Raymond and Beverly Sackler Foundation Cardiovascular Laboratory, New
Haven, Connecticut, United States of America
| | - Timur O. Yarovinsky
- Department of Internal Medicine, Section of Cardiovascular Medicine,
Cardiovascular Research Center, Yale University School of Medicine, New Haven,
Connecticut, United States of America
- Department of Immunobiology, Yale University School of Medicine, New
Haven, Connecticut, United States of America
- Raymond and Beverly Sackler Foundation Cardiovascular Laboratory, New
Haven, Connecticut, United States of America
| | - Vinod S. Ramgolam
- Department of Internal Medicine, Section of Cardiovascular Medicine,
Cardiovascular Research Center, Yale University School of Medicine, New Haven,
Connecticut, United States of America
- Department of Immunobiology, Yale University School of Medicine, New
Haven, Connecticut, United States of America
- Raymond and Beverly Sackler Foundation Cardiovascular Laboratory, New
Haven, Connecticut, United States of America
| | - Matthias Gaestel
- Institute of Biochemistry, Medical School Hannover, Hannover,
Germany
| | - Ruggero Pardi
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele,
Milan, Italy
| | - Jeffrey R. Bender
- Department of Internal Medicine, Section of Cardiovascular Medicine,
Cardiovascular Research Center, Yale University School of Medicine, New Haven,
Connecticut, United States of America
- Department of Immunobiology, Yale University School of Medicine, New
Haven, Connecticut, United States of America
- Raymond and Beverly Sackler Foundation Cardiovascular Laboratory, New
Haven, Connecticut, United States of America
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Tanaka A, Aoki F, Suzuki MG. Conserved Domains in the Transformer Protein Act Complementary to Regulate Sex-Specific Splicing of Its Own Pre-mRNA. Sex Dev 2018; 12:180-190. [PMID: 29804107 DOI: 10.1159/000489444] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/29/2017] [Indexed: 01/13/2023] Open
Abstract
The transformer (tra) gene, which is a female-determining master gene in the housefly Musca domestica, acts as a memory device for sex determination via its auto-regulatory function, i.e., through the contribution of the TRA protein to female-specific splicing of its own pre-mRNA. The TRA protein contains 4 small domains that are specifically conserved among TRA proteins (domains 1-4). Domain 2, also named TRA-CAM domain, is the most conserved, but its function remains unknown. To examine whether these domains are involved in the auto-regulatory function, we performed in vitro splicing assays using a tra minigene containing a partial genomic sequence of the M. domestica tra (Mdtra) gene. Co-transfection of the Mdtra minigene and an MdTRA protein expression vector into cultured insect cells strongly induced female-specific splicing of the minigene. A series of deletion mutation analyses demonstrated that these domains act complementarily to induce female-specific splicing. Domain 1 and the TRA-CAM domain were necessary for the female-specific splicing when the MdTRA protein lacked both domains 3 and 4. In this situation, mutation of the well-conserved 3 amino acids (GEG) in the TRA-CAM domain significantly reduced the female-specific splicing activity of MdTRA. GST-pull down analyses demonstrated that the MdTRA protein specifically enriched on the male-specific exonic region (exon 2b), which contains the putative TRA/TRA-2 binding sites, and that the GEG mutation disrupts this enrichment. Since the MdTRA protein interacts with its own pre-mRNA through TRA-2, our findings suggest that the conserved amino acid residues in the TRA-CAM domain may be crucial for the interaction between MdTRA and TRA-2, enhancing MdTRA recruitment on its pre-mRNA to induce female-specific splicing of tra in the housefly.
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11
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Esnault S, Hebert AS, Jarjour NN, Coon JJ, Mosher DF. Proteomic and Phosphoproteomic Changes Induced by Prolonged Activation of Human Eosinophils with IL-3. J Proteome Res 2018; 17:2102-2111. [PMID: 29706072 DOI: 10.1021/acs.jproteome.8b00057] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Purified human eosinophils treated for 18-24 h with IL-3 adopt a unique activated phenotype marked by increased reactivity to aggregated immunoglobulin-G (IgG). To characterize this phenotype, we quantified protein abundance and phosphorylation by multiplexed isobaric labeling combined with high-resolution mass spectrometry. Purified blood eosinophils of five individuals were treated with IL-3 or no cytokine for 20 h, and comparative data were obtained on abundance of 5385 proteins and phosphorylation at 7330 sites. The 1150 proteins that were significantly up-regulated ( q < 0.05, pairwise t test with Benjamini-Hochberg correction) by IL-3 included the IL3RA and CSF2RB subunits of the IL-3 receptor, the low-affinity receptor for IgG (FCGR2B), 96 proteins involved in protein translation, and 55 proteins involved in cytoskeleton organization. Among the 703 proteins that decreased were 78 mitochondrial proteins. Dynamic regulation of protein phosphorylation was detected at 4218 sites. These included multiple serines in CSF2RB; Y694 of STAT5, a key site of activating phosphorylation downstream of IL3RA/CSF2RB; and multiple sites in RPS6KA1, RPS6, and EIF4B, which are responsible for translational initiation. We conclude that IL-3 up-regulates overall protein synthesis and targets specific proteins for up-regulation, including its own receptor.
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Affiliation(s)
- Stephane Esnault
- Department of Medicine , University of Wisconsin , Madison , Wisconsin 53792 , United States
| | - Alexander S Hebert
- Department of Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States
| | - Nizar N Jarjour
- Department of Medicine , University of Wisconsin , Madison , Wisconsin 53792 , United States
| | - Joshua J Coon
- Department of Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States.,Department of Biomolecular Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States.,Morgridge Institute for Research , Madison , Wisconsin 53715 , United States.,Genome Center of Wisconsin , Madison , Wisconsin 53706 , United States
| | - Deane F Mosher
- Department of Medicine , University of Wisconsin , Madison , Wisconsin 53792 , United States.,Department of Biomolecular Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States
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12
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Ezegbunam W, Foronjy R. Posttranscriptional control of airway inflammation. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 9. [PMID: 29071794 DOI: 10.1002/wrna.1455] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/07/2017] [Accepted: 09/08/2017] [Indexed: 12/18/2022]
Abstract
Acute inflammation in the lungs is a vital protective response, efficiently and swiftly eliminating inciters of tissue injury. However, in respiratory diseases characterized by chronic inflammation, such as chronic obstructive pulmonary disease and asthma, enhanced expression of inflammatory mediators leads to tissue damage and impaired lung function. Although transcription is an essential first step in the induction of proinflammatory genes, tight regulation of inflammation requires more rapid, flexible responses. Increasing evidence shows that such responses are achieved by posttranscriptional mechanisms directly affecting mRNA stability and translation initiation. RNA-binding proteins, microRNAs, and long noncoding RNAs interact with messenger RNA and each other to impact the stability and/or translation of mRNAs implicated in lung inflammation. Recent research has shown that these biological processes play a central role in the pathogenesis of several important pulmonary conditions. This review will highlight several posttranscriptional control mechanisms that influence lung inflammation and the known associations of derangements in these mechanisms with common respiratory diseases. WIREs RNA 2018, 9:e1455. doi: 10.1002/wrna.1455 This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Turnover and Surveillance > Regulation of RNA Stability.
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Affiliation(s)
- Wendy Ezegbunam
- Division of Pulmonary and Critical Care Medicine, Department of Medicine and Cell Biology, SUNY Downstate Medical Center, Brooklyn, NY, USA
| | - Robert Foronjy
- Division of Pulmonary and Critical Care Medicine, Department of Medicine and Cell Biology, SUNY Downstate Medical Center, Brooklyn, NY, USA
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13
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Esnault S, Shen ZJ, Malter JS. Protein Translation and Signaling in Human Eosinophils. Front Med (Lausanne) 2017; 4:150. [PMID: 28971096 PMCID: PMC5609579 DOI: 10.3389/fmed.2017.00150] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 09/01/2017] [Indexed: 01/01/2023] Open
Abstract
We have recently reported that, unlike IL-5 and GM-CSF, IL-3 induces increased translation of a subset of mRNAs. In addition, we have demonstrated that Pin1 controls the activity of mRNA binding proteins, leading to enhanced mRNA stability, GM-CSF protein production and prolonged eosinophil (EOS) survival. In this review, discussion will include an overview of cap-dependent protein translation and its regulation by intracellular signaling pathways. We will address the more general process of mRNA post-transcriptional regulation, especially regarding mRNA binding proteins, which are critical effectors of protein translation. Furthermore, we will focus on (1) the roles of IL-3-driven sustained signaling on enhanced protein translation in EOS, (2) the mechanisms regulating mRNA binding proteins activity in EOS, and (3) the potential targeting of IL-3 signaling and the signaling leading to mRNA binding activity changes to identify therapeutic targets to treat EOS-associated diseases.
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Affiliation(s)
- Stephane Esnault
- Department of Medicine, Allergy, Pulmonary, and Critical Care Medicine Division, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| | - Zhong-Jian Shen
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - James S Malter
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, United States
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14
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Ge S, Li T, Yao Q, Yan H, Huiyun Z, Zheng Y, Zhang B, He S. Expression of proteinase-activated receptor (PAR)-2 in monocytes from allergic patients and potential molecular mechanism. Cell Biol Toxicol 2016; 32:529-542. [PMID: 27423452 DOI: 10.1007/s10565-016-9353-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/05/2016] [Indexed: 02/05/2023]
Abstract
Serine proteases play an important role in inflammation via PARs. However, little is known of expression levels of PARs on monocytes of allergic patients, and influence of serine proteases and PARs on TNF-α secretion from monocytes. Using quantitative real-time PCR (qPCR) and flowcytometry techniques, we observed that the expression level of PAR-2 in monocytes of patients with allergic rhinitis and asthma was increased by 42.9 and 38.2 %. It was found that trypsin, thrombin, and tryptase induced up to 200, 320, and 310 % increase in TNF-α release from monocytes at 16 h, respectively. PAR-1 agonist peptide, SFLLR-NH2, and PAR-2 agonist peptide tc-LIGRLO-NH2 provoked up to 210 and 240 % increase in release of TNF-α. Since SCH 79797, a PAR-1 antagonist, and PD98059, an inhibitor of ERK inhibited thrombin- and SFLLR-NH2-induced TNF-α release, the action of thrombin is most likely through a PAR-1- and ERK-mediated signaling mechanism. Similarly, because FSLLRN-NH2, an inhibitor of PAR-2 diminished tryptase- and tc-LIGRLO-NH2-induced TNF-α release, the action of tryptase appears PAR-2 dependent. Moreover, in vivo study showed that both recombinant cockroach major allergens Per a 1 and Per a 7 provoked upregulation of PAR-2 and PAR-1 expression on CD14+ cells in OVA-sensitized mouse peritoneum. In conclusion, increased expression of PAR-2 in monocytes of AR and asthma implicates that PAR-2 likely play a role in allergy. PAR-2- and PAR-1-mediated TNF-α release from monocytes suggests that these unique protease receptors are involved in the pathogenesis of inflammation.
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Affiliation(s)
- Shuqing Ge
- Allergy and Clinical Immunology Research Centre, the First Affiliated Hospital of Liaoning Medical University, No. 2, Section 5, Renmin Street, Guta District, Jinzhou, Liaoning, 121001, People's Republic of China
- Department of Dentistry, the First Affiliated Hospital of Liaoning Medical University, Jinzhou, Liaoning, 121001, China
| | - Tao Li
- Department of Infectious Diseases, Shantou University Medical College, Shantou, 515031, China
| | - Qijian Yao
- Department of Infectious Diseases, Shantou University Medical College, Shantou, 515031, China
| | - Hongling Yan
- Clinical Research Centre, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, 210029, China
| | - Zhang Huiyun
- Allergy and Clinical Immunology Research Centre, the First Affiliated Hospital of Liaoning Medical University, No. 2, Section 5, Renmin Street, Guta District, Jinzhou, Liaoning, 121001, People's Republic of China
| | - Yanshan Zheng
- Department of Infectious Diseases, Shantou University Medical College, Shantou, 515031, China
| | - Bin Zhang
- Department of Dentistry, the First Affiliated Hospital of Liaoning Medical University, Jinzhou, Liaoning, 121001, China
| | - Shaoheng He
- Allergy and Clinical Immunology Research Centre, the First Affiliated Hospital of Liaoning Medical University, No. 2, Section 5, Renmin Street, Guta District, Jinzhou, Liaoning, 121001, People's Republic of China.
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15
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Shen ZJ, Malter JS. Determinants of eosinophil survival and apoptotic cell death. Apoptosis 2015; 20:224-34. [PMID: 25563855 DOI: 10.1007/s10495-014-1072-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Eosinophils (Eos) are potent inflammatory cells and abundantly present in the sputum and lung of patients with allergic asthma. During both transit to and residence in the lung, Eos contact prosurvival cytokines, particularly IL-3, IL-5 and GM-CSF, that attenuate cell death. Cytokine signaling modulates the expression and function of a number of intracellular pro- and anti-apoptotic molecules. Both intrinsic mitochondrial and extrinsic receptor-mediated pathways are affected. This article discusses the fundamental role of the extracellular and intracellular molecules that initiate and control survival decisions by human Eos and highlights the role of the cis-trans isomerase, Pin1 in controlling these processes.
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Affiliation(s)
- Zhong-Jian Shen
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9072, USA,
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16
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Shen ZJ, Malter JS. Regulation of AU-Rich Element RNA Binding Proteins by Phosphorylation and the Prolyl Isomerase Pin1. Biomolecules 2015; 5:412-34. [PMID: 25874604 PMCID: PMC4496679 DOI: 10.3390/biom5020412] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 03/23/2015] [Accepted: 03/31/2015] [Indexed: 01/19/2023] Open
Abstract
The accumulation of 3' untranslated region (3'-UTR), AU-rich element (ARE) containing mRNAs, are predominantly controlled at the post-transcriptional level. Regulation appears to rely on a variable and dynamic interaction between mRNA target and ARE-specific binding proteins (AUBPs). The AUBP-ARE mRNA recognition is directed by multiple intracellular signals that are predominantly targeted at the AUBPs. These include (but are unlikely limited to) methylation, acetylation, phosphorylation, ubiquitination and isomerization. These regulatory events ultimately affect ARE mRNA location, abundance, translation and stability. In this review, we describe recent advances in our understanding of phosphorylation and its impact on conformation of the AUBPs, interaction with ARE mRNAs and highlight the role of Pin1 mediated prolyl cis-trans isomerization in these biological process.
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Affiliation(s)
- Zhong-Jian Shen
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390-8548, USA.
| | - James S Malter
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX 75390-8548, USA.
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17
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Ghosh S, Hoselton SA, Dorsam GP, Schuh JM. Hyaluronan fragments as mediators of inflammation in allergic pulmonary disease. Immunobiology 2014; 220:575-88. [PMID: 25582403 DOI: 10.1016/j.imbio.2014.12.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 12/10/2014] [Accepted: 12/15/2014] [Indexed: 12/22/2022]
Abstract
Asthma is frequently caused and/or exacerbated by sensitization to allergens, which are ubiquitous in many indoor and outdoor environments. Severe asthma is characterized by airway hyperresponsiveness and bronchial constriction in response to an inhaled allergen, leading to a disease course that is often very difficult to treat with standard asthma therapies. As a result of interactions among inflammatory cells, structural cells, and the intercellular matrix of the allergic lung, patients with sensitization to allergens may experience a greater degree of tissue injury followed by airway wall remodeling and progressive, accumulated pulmonary dysfunction as part of the disease sequela. In addition, turnover of extracellular matrix (ECM) components is a hallmark of tissue injury and repair. This review focuses on the role of the glycosaminoglycan hyaluronan (HA), a component of the ECM, in pulmonary injury and repair with an emphasis on allergic asthma. Both the synthesis and degradation of the ECM are critical contributors to tissue repair and remodeling. Fragmented HA accumulates during tissue injury and functions in ways distinct from the larger native polymer. There is gathering evidence that HA degradation products are active participants in stimulating the expression of inflammatory genes in a variety of immune cells at the injury site. In this review, we will consider recent advances in the understanding of the mechanisms that are associated with HA accumulation and inflammatory cell recruitment in the asthmatic lung.
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Affiliation(s)
- Sumit Ghosh
- Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108, USA.
| | - Scott A Hoselton
- Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108, USA
| | - Glenn P Dorsam
- Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108, USA
| | - Jane M Schuh
- Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108, USA
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18
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Ghosh S, Samarasinghe AE, Hoselton SA, Dorsam GP, Schuh JM. Hyaluronan deposition and co-localization with inflammatory cells and collagen in a murine model of fungal allergic asthma. Inflamm Res 2014; 63:475-84. [PMID: 24519432 DOI: 10.1007/s00011-014-0719-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 01/20/2014] [Accepted: 01/24/2014] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE Allergic asthma is a chronic inflammatory disease of the airways characterized by excessive inflammation and remodeling of the extracellular matrix (ECM) and associated cells of the airway wall. Under inflammatory conditions, hyaluronan (HA), a major component of the ECM, undergoes dynamic changes, which may in turn affect the recruitment and activation of inflammatory cells leading to acute and chronic immunopathology of allergic asthma. METHODS In the present study, we measured the changes in HA levels generated at sites of inflammation, and examined its effect on inflammatory responses and collagen deposition in an Aspergillus fumigatus murine inhalational model of allergic asthma. RESULTS We found that HA levels are elevated in allergic animals and that the increase correlated with the influx of inflammatory cells 5 days after the second allergen challenge. This increase in HA levels appeared largely due to upregulation of hyaluronidase-1 (HYAL1) and hyaluronidase-2 (HYAL2). Furthermore, HA co-localizes with areas of new collagen synthesis and deposition. CONCLUSIONS Overall, our findings contribute to the growing literature that focuses on the components of ECM as inflammatory mediators rather than mere structural support products. The evidence of HA localization in fungal allergic asthma provides the impetus to study HA more closely with allergic leukocytes in murine models. Further studies examining HA's role in mediating cellular responses may help to develop targets for treatment in patients with severe asthma due to fungal sensitization.
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Affiliation(s)
- Sumit Ghosh
- Department of Veterinary and Microbiological Sciences, North Dakota State University, Dept 7690, P.O. Box 6050, Fargo, ND, 58105, USA,
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Chen J, Cascio J, Magee JD, Techasintana P, Gubin MM, Dahm GM, Calaluce R, Yu S, Atasoy U. Posttranscriptional gene regulation of IL-17 by the RNA-binding protein HuR is required for initiation of experimental autoimmune encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2013; 191:5441-50. [PMID: 24166976 DOI: 10.4049/jimmunol.1301188] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
IL-17 is a proinflammatory cytokine produced by activated Th17 cells and other immune cells. IL-17-producing Th17 cells are major contributors to chronic inflammatory and autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis, and inflammatory bowel disease. Although the transcriptional regulation of Th17 cells is well understood, the posttranscriptional regulation of IL-17 gene expression remains unknown. The RNA-binding protein HuR positively regulates the stability of many target mRNAs via binding the AU-rich elements present in the 3' untranslated region of many inflammatory cytokines including IL-4, IL-13, and TNF-α. However, the regulation of IL-17 expression by HuR has not been established. CD4(+) Th17 cells from HuR knockout mice had decreased IL-17 steady-state mRNA and protein levels compared with wild-type Th17 cells, as well as decreases in frequency of IL-17(+) cells. Moreover, we demonstrated that HuR directly binds to the IL-17 mRNA 3' untranslated region by using RNA immunoprecipitation and biotin pulldown assays. In addition, the knockout of HuR decreased cellular proliferation of CD4(+) T cells. Mice with adoptively transferred HuR KO Th17 cells had delayed initiation and reduced disease severity in the onset of experimental autoimmune encephalomyelitis compared with wild-type Th17 cells. Our results reveal a HuR-induced posttranscriptional regulatory mechanism of Th17 differentiation that influences IL-17 expression. These findings may provide novel therapeutic targets for the treatment of Th17-mediated autoimmune neuroinflammation.
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Affiliation(s)
- Jing Chen
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65212
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20
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Zhang H, Yang H, Ma W, Zhang Z, He S. Modulation of PAR expression and tryptic enzyme induced IL-4 production in mast cells by IL-29. Cytokine 2013; 61:469-77. [PMID: 23218741 DOI: 10.1016/j.cyto.2012.10.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Revised: 09/17/2012] [Accepted: 10/31/2012] [Indexed: 12/25/2022]
Abstract
Interleukin (IL)-29 is a relatively newly discovered cytokine, which has been shown to be actively involved in the pathogenesis of allergic inflammation. However, little is known of the effects of IL-29 on protease activated receptor (PAR) expression and potential mechanisms of cytokine production in mast cells. In the present study, we examined potential influence of IL-29 on PAR expression and cytokine production in P815 and bone marrow derived mast cells (BMMCs) by using flow cytometry analysis, quantitative real time PCR, and ELISA techniques. The results showed that IL-29 downregulated the expression of PAR-1 by up to 56.2%, but had little influence on the expression of PAR-2, PAR-3 and PAR-4. IL-29 also induced downregulation of expression of PAR-1 mRNA. However, when mast cells were pre-incubated with IL-29, thrombin-, trypsin- and tryptase-induced expression of PAR-2, PAR-3 and PAR-4 was upregulated, respectively. IL-29 provoked approximately up to 1.9-fold increase in IL-4 release when mast cells was challenged with IL-29. Administration of IL-29 blocking antibody, AG490 or LY294002 abolished IL-29-induced IL-4 release from P815 cells. It was found that IL-29 diminished trypsin- and tryptase-induced IL-4 release from P815 cells following 16 h incubation. In conclusion, IL-29 can regulate expression of PARs and tryptase- and trypsin-induced IL-4 production in mast cells, through which participates in the mast cell related inflammation.
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Affiliation(s)
- Huiyun Zhang
- Department of Pathophysiology, Hainan Medical College, Haikou, Hainan 571101, China
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21
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Damgaard CK, Lykke-Andersen J. Regulation of ARE-mRNA Stability by Cellular Signaling: Implications for Human Cancer. Cancer Treat Res 2013; 158:153-80. [PMID: 24222358 DOI: 10.1007/978-3-642-31659-3_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
During recent years, it has become clear that regulation of mRNA stability is an important event in the control of gene expression. The stability of a large class of mammalian mRNAs is regulated by AU-rich elements (AREs) located in the mRNA 3' UTRs. mRNAs with AREs are inherently labile but as a response to different cellular cues they can become either stabilized, allowing expression of a given gene, or further destabilized to silence their expression. These tightly regulated mRNAs include many that encode growth factors, proto-oncogenes, cytokines, and cell cycle regulators. Failure to properly regulate their stability can therefore lead to uncontrolled expression of factors associated with cell proliferation and has been implicated in several human cancers. A number of transfactors that recognize AREs and regulate the translation and degradation of ARE-mRNAs have been identified. These transfactors are regulated by signal transduction pathways, which are often misregulated in cancers. This chapter focuses on the function of ARE-binding proteins with an emphasis on their regulation by signaling pathways and the implications for human cancer.
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22
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Li W, Wang X, Gao G. Expression of YB-1 enhances production of murine leukemia virus vectors by stabilizing genomic viral RNA. Protein Cell 2012; 3:943-9. [PMID: 23225179 DOI: 10.1007/s13238-012-2090-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 09/04/2012] [Indexed: 12/25/2022] Open
Abstract
Murine leukemia virus (MLV)-based retroviral vectors is widely used for gene transfer and basic research, and production of high-titer retroviral vectors is very important. Here we report that expression of the Y-box binding protein 1 (YB-1) enhanced the production of infectious MLV vectors. YB-1 specifically increased the stability of viral genomic RNA in virus-producing cells, and thus increasing viral RNA levels in both producer cells and virion particles. The viral element responsive to YB-1 was mapped to the repeat sequence (R region) in MLV genomic RNA. These results identified YB-1 as a MLV mRNA stabilizer, which can be used for improving production of MLV vectors.
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Affiliation(s)
- Wei Li
- Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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23
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Cheng G, Swaidani S, Sharma M, Lauer ME, Hascall VC, Aronica MA. Correlation of hyaluronan deposition with infiltration of eosinophils and lymphocytes in a cockroach-induced murine model of asthma. Glycobiology 2012; 23:43-58. [PMID: 22917573 DOI: 10.1093/glycob/cws122] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Asthma is a chronic inflammatory disease that exhibits airway remodeling with changes in the extracellular matrix (ECM). The role of the ECM in mediating these changes is poorly understood. Hyaluronan (HA), a major component of the ECM, has been implicated in many biological processes in diseases. This study investigates the processes involved in HA synthesis, deposition and localization during the propagation of cockroach-induced asthma. Mice were sensitized and challenged with cockroach antigen, and sacrificed at various time points during an 8-week challenge protocol. Analysis of bronchoalveolar lavage (BAL) fluid revealed an increase in total nucleated cells as early as 6h, which peaked at 6 days. Histopathologic analysis of the lung tissue revealed an influx of inflammatory cells at the peribronchial and perivascular regions starting at 12 h, which peaked at 6 days and persisted to 8 weeks. Eosinophils predominated in the early time points while lymphocytes predominated during the late time points. Quantitative polymerase chain reaction (PCR) data showed that hyaluronan synthase 1 (HAS1) mRNA peaked within 6 h and then declined. HAS2 mRNA also peaked within 6 h but remained elevated throughout the 8-week exposure course. HA levels in lung tissue and BAL increased at 12 h and peaked by 6 and 8 days, respectively. Inflammatory cells and new collagen formation localized in areas of HA deposition. Taken together, these data support a role for HA in the pathogenesis in asthma.
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Eliseeva IA, Kim ER, Guryanov SG, Ovchinnikov LP, Lyabin DN. Y-box-binding protein 1 (YB-1) and its functions. BIOCHEMISTRY (MOSCOW) 2012; 76:1402-33. [PMID: 22339596 DOI: 10.1134/s0006297911130049] [Citation(s) in RCA: 250] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review describes the structure and functions of Y-box binding protein 1 (YB-1) and its homologs. Interactions of YB-1 with DNA, mRNAs, and proteins are considered. Data on the participation of YB-1 in DNA reparation and transcription, mRNA splicing and translation are systematized. Results on interactions of YB-1 with cytoskeleton components and its possible role in mRNA localization are discussed. Data on intracellular distribution of YB-1, its redistribution between the nucleus and the cytoplasm, and its secretion and extracellular functions are summarized. The effect of YB-1 on cell differentiation, its involvement in extra- and intracellular signaling pathways, and its role in early embryogenesis are described. The mechanisms of regulation of YB-1 expression in the cell are presented. Special attention is paid to the involvement of YB-1 in oncogenic cell transformation, multiple drug resistance, and dissemination of tumors. Both the oncogenic and antioncogenic activities of YB-1 are reviewed. The potential use of YB-1 in diagnostics and therapy as an early cancer marker and a molecular target is discussed.
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Affiliation(s)
- I A Eliseeva
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
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25
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Abstract
The cytoplasmic events that control mammalian gene expression, primarily mRNA stability and translation, potently influence the cellular response to internal and external signals. The ubiquitous RNA-binding protein (RBP) HuR is one of the best-studied regulators of cytoplasmic mRNA fate. Through its post-transcriptional influence on specific target mRNAs, HuR can alter the cellular response to proliferative, stress, apoptotic, differentiation, senescence, inflammatory and immune stimuli. In light of its central role in important cellular functions, HuR's role in diseases in which these responses are aberrant is increasingly appreciated. Here, we review the mechanisms that control HuR function, its influence on target mRNAs, and how impairment in HuR-governed gene expression programs impact upon different disease processes. We focus on HuR's well-recognized implication in cancer and chronic inflammation, and discuss emerging studies linking HuR to cardiovascular, neurological, and muscular pathologies. We also discuss the progress, potential, and challenges of targeting HuR therapeutically.
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Affiliation(s)
- Subramanya Srikantan
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, MD 21224, USA
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26
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Raffetseder U, Liehn EA, Weber C, Mertens PR. Role of cold shock Y-box protein-1 in inflammation, atherosclerosis and organ transplant rejection. Eur J Cell Biol 2011; 91:567-75. [PMID: 21943779 DOI: 10.1016/j.ejcb.2011.07.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 07/05/2011] [Accepted: 07/08/2011] [Indexed: 12/14/2022] Open
Abstract
Chemokines (chemoattractant cytokines) are crucial regulators of immune cell extravasation from the bloodstream into inflamed tissue. Dysfunctional regulation and perpetuated chemokine gene expression are linked to progressive chronic inflammatory diseases and, in respect to transplanted organs, may trigger graft rejection. RANTES (regulated upon activation, normal T cell expressed and secreted (also known as CCL5)) is a model chemokine with relevance in numerous inflammatory diseases where the innate immune response predominates. Transcription factor Y-box binding protein-1 (YB-1) serves as a trans-regulator of CCL5 gene transcription in vascular smooth muscle cells and leucocytes. This review provides an update on YB-1 as a mediator of inflammatory processes and focuses on the role of YB-1 in CCL5 expression in diseases with monocytic cell infiltrates, albeit acute or chronic. Paradigms of such diseases encompass atherosclerosis and transplant rejection where cold shock protein YB-1 takes a dominant role in transcriptional regulation.
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Affiliation(s)
- Ute Raffetseder
- Department of Nephrology and Clinical Immunology, University Hospital RWTH-Aachen, Pauwelsstrasse 30, 52057 Aachen, Germany.
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Wang ZH, Li SJ, Qi Y, Zhao JJ, Liu XY, Han Y, Xu P, Chen XH. HuD regulates the cpg15 expression via the 3'-UTR and AU-rich element. Neurochem Res 2011; 36:1027-36. [PMID: 21424739 DOI: 10.1007/s11064-011-0443-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2011] [Indexed: 11/29/2022]
Abstract
The candidate plasticity related gene 15 (cpg15) plays important roles in neural development and plasticity. In the present study, we studied the role of the cpg15 3'-untranslated region (UTR) in regulating the expression of the gene. The results showed that the presence of the 3'-UTR significantly decreases, while loss of a putative AU-rich element (ARE) in the 3'-UTR increases the cpg15 expression, indicating that the 3'-UTR and ARE may be essential for regulation of cpg15 expression. In addition, HuD, a neural-specific RNA binding protein, increased the cpg15 expression, which depends on the presence of the 3'-UTR and ARE. RNA-binding protein immunoprecipitation (RIP) assay demonstrated that HuD forms a complex with cpg15 mRNA in the cells of rat hippocampus. Deletion of HuD domains RRM1 plus RRM2 or Hinge region plus RRM3 attenuates the function of HuD in enhancing the cpg15 expression. The results suggest that HuD regulates the cpg15 expression via the 3'-UTR-mediated mechanism, which requires the presence of the ARE.
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Affiliation(s)
- Zhong-Hui Wang
- Laboratory of Genomic Physiology and State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032, People's Republic of China
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28
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Jiang D, Liang J, Noble PW. Hyaluronan as an immune regulator in human diseases. Physiol Rev 2011; 91:221-64. [PMID: 21248167 DOI: 10.1152/physrev.00052.2009] [Citation(s) in RCA: 747] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Accumulation and turnover of extracellular matrix components are the hallmarks of tissue injury. Fragmented hyaluronan stimulates the expression of inflammatory genes by a variety of immune cells at the injury site. Hyaluronan binds to a number of cell surface proteins on various cell types. Hyaluronan fragments signal through both Toll-like receptor (TLR) 4 and TLR2 as well as CD44 to stimulate inflammatory genes in inflammatory cells. Hyaluronan is also present on the cell surface of epithelial cells and provides protection against tissue damage from the environment by interacting with TLR2 and TLR4. Hyaluronan and hyaluronan-binding proteins regulate inflammation, tissue injury, and repair through regulating inflammatory cell recruitment, release of inflammatory cytokines, and cell migration. This review focuses on the role of hyaluronan as an immune regulator in human diseases.
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Affiliation(s)
- Dianhua Jiang
- Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Duke University School of Medicine, Durham, North Carolina 27710, USA.
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29
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Guo X, Wu Y, Hartley RS. MicroRNA-125a represses cell growth by targeting HuR in breast cancer. RNA Biol 2010; 6:575-83. [PMID: 19875930 DOI: 10.4161/rna.6.5.10079] [Citation(s) in RCA: 164] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
MicroRNAs (miRNAs) are a class of naturally occurring, small, non-coding RNAs that control gene expression during development,normal cell function and disease. Although there is emerging evidence that some miRNAs can function as oncogenes or tumor suppressors, there is limited understanding of the role of miRNAs in cancer. In this study, we observed that the expression of miR-125a was inversely correlated with HuR expression in several different breast carcinoma cell lines. HuR is a stress-induced RNA binding protein whose expression is elevated or localization perturbed in several different cancers. Increased cytoplasmic localization of HuR is a prognostic marker in breast cancer. Real time PCR and gene reporter assays indicated that HuR was translationally repressed by miR-125a. Re-establishing miR-125a expression in breast cancer cells decreased HuR protein level and inhibited cell growth. Using MCF-7 breast cancer cells, we further clarified that miR-125a inhibited cell growth via a dramatic suppression of cell proliferation and promotion of apoptosis.In addition, cell migration was also inhibited by miR-125a overexpression. Importantly, the repression of cell proliferation and migration engendered by miR-125a was partly rescued by HuR re-expression. Our results suggest that miR-125a may function as a tumor suppressor for breast cancer, with HuR as a direct and functional target.
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Affiliation(s)
- Xu Guo
- Department of Cell Biology and Physiology and Cancer Research and Treatment Center, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
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30
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Papadopoulou C, Patrinou-Georgoula M, Guialis A. Extensive association of HuR with hnRNP proteins within immunoselected hnRNP and mRNP complexes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2010; 1804:692-703. [DOI: 10.1016/j.bbapap.2009.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 10/08/2009] [Accepted: 11/09/2009] [Indexed: 10/20/2022]
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Zhang H, Lin L, Yang H, Zhang Z, Yang X, Zhang L, He S. Induction of IL-13 production and upregulation of gene expression of protease activated receptors in P815 cells by IL-6. Cytokine 2010; 50:138-45. [PMID: 20189822 DOI: 10.1016/j.cyto.2010.02.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2009] [Revised: 12/22/2009] [Accepted: 02/02/2010] [Indexed: 01/08/2023]
Abstract
Interleukin (IL)-6 is a multifunctional cytokine which has been showed to induce up-regulated expression of Fc epsilon RI receptor and histamine production in mast cells. However, little is known of its effects on Th2 cytokine secretion and protease activated receptor (PAR) expression in mast cells. In the present study, we examined potential influence of IL-6 on IL-13, IL-4 and IL-10 release from P815 cells and PAR expression on P815 cells by using flow cytometry analysis, quantitative real-time PCR, ELISA and cellular activation of signaling ELISA (CASE) techniques. The results showed that IL-6 induced up to 1.8-fold increase in IL-13, but not IL-4 or IL-10 release from P815 cells, and FSLLRY-NH(2) did not affect IL-6 induced IL-13 release. Tryptase elicited 2.0-fold increase in IL-13 release from P815 cells, which can be inhibited by IL-6. IL-6 elicited the up-regulated expression of PAR-1, PAR-2, PAR-3 and PAR-4 mRNAs, but had little effects on expression of PAR proteins. U0126, PD98059 and LY204002 abolished IL-6 induced IL-13 release when they were preincubated with P815 cells, indicating ERK and Akt cell signaling pathways may be involved in the event. In conclusion, IL-6 can stimulate IL-13 release from mast cells through an ERK and Akt cell signaling pathway dependent, but PAR independent mechanism.
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Affiliation(s)
- Huiyun Zhang
- Department of Pathophysiology, Hainan Medical College, Haikou, Hainan, China.
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Sturrock A, Vollbrecht T, Mir-Kasimov M, McManus M, Wilcoxen SE, Paine R. Mechanisms of suppression of alveolar epithelial cell GM-CSF expression in the setting of hyperoxic stress. Am J Physiol Lung Cell Mol Physiol 2009; 298:L446-53. [PMID: 20034963 DOI: 10.1152/ajplung.00161.2009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Pulmonary expression of granulocyte/macrophage colony-stimulating factor (GM-CSF) is critically important for normal functional maturation of alveolar macrophages. We found previously that lung GM-CSF is dramatically suppressed in mice exposed to hyperoxia. Alveolar epithelial cells (AEC) are a major source of GM-CSF in the peripheral lung, and in vivo hyperoxia resulted in greatly reduced expression of GM-CSF protein by AEC ex vivo. We now explore the mechanisms responsible for this effect, using primary cultures of murine AEC exposed to hyperoxia in vitro. Exposure of AEC to 80% oxygen/5% CO(2) for 48 h did not induce overt toxicity, but resulted in significantly decreased GM-CSF protein and mRNA expression compared with cells in normoxia. Similar effects were seen when AEC were stressed with serum deprivation, an alternative inducer of oxidative stress. The effects in AEC were opposite those in a murine lung epithelial cell line (MLE-12 cells), in which hyperoxia induced GM-CSF expression. Both hyperoxia and serum deprivation resulted in increased intracellular reactive oxygen species (ROS) in AEC. Hyperoxia and serum deprivation induced significantly accelerated turnover of GM-CSF mRNA. Treatment of AEC with catalase during oxidative stress preserved GM-CSF protein and mRNA and was associated with stabilization of GM-CSF mRNA. We conclude that hyperoxia-induced suppression of AEC GM-CSF expression is a function of ROS-induced destabilization of GM-CSF mRNA. We speculate that AEC oxidative stress results in significantly impaired pulmonary innate immune defense due to effects on local GM-CSF expression in the lung.
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Affiliation(s)
- Anne Sturrock
- Department of Veterans Affairs Medicine Center, and Division of Respiratory, Critical Care, and Occupational Pulmonary Medicine, University of Utah School of Medicine, 26 North 1900 East, Salt Lake City, UT 84132, USA
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Zhang H, Yang H, Zhang L, Yang X, Zhang Z, Lin Q, He S. Induction of IL-4 release and upregulated expression of protease activated receptors by GM-CSF in P815 cells. Cytokine 2009; 48:196-202. [PMID: 19651524 DOI: 10.1016/j.cyto.2009.07.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Revised: 06/02/2009] [Accepted: 07/06/2009] [Indexed: 11/16/2022]
Abstract
GM-CSF has been showed to be able to induce up-regulated receptor and cytokine expression in mast cells in inflammatory conditions. However, little is known of its effects on protease activated receptor (PAR) expression and Th2 cytokine secretion from mast cells. In the present study, we examined potential influence of GM-CSF on mast cell PAR expression and IL-4 and IL-10 release by using flow cytometry analysis, quantitative real time PCR, ELISA and cellular activation of signaling ELISA (CASE) techniques. The results showed that GM-CSF induced up to 3.0-fold increase in IL-4 release from P815 cells, and FSLLRY-NH(2) and trans-cinnamoyl (tc)-YPGKF-NH(2) did not affect GM-CSF induced IL-4 release. GM-CSF reduced tryptase and trypsin induced IL-4 release by up to approximately 55.8% and 70.3%, respectively. GM-CSF elicited the upregulated expression of PAR-1, PAR-2, PAR-3 and PAR-4 mRNAs, but enhanced only PAR-4 protein expression in P815 cells. U0126, PD98059 and LY204002 almost completely abolished GM-CSF induced IL-4 release when they were preincubated with P815 cells for 30 min, indicating ERK and Akt cell signaling pathways may be involved in the event. In conclusion, GM-CSF can stimulate IL-4 release from mast cells through an ERK and Akt cell signaling pathway dependent, but PAR independent mechanism. GM-CSF may serve as a regulator for IL-4 production in mast cells and through which participates in the mast cell related inflammation.
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Affiliation(s)
- Huiyun Zhang
- Department of Pathophysiology, Hainan Medical College, Haikou, Hainan 571101, China
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Kelly EAB, Koziol-White CJ, Clay KJ, Liu LY, Bates ME, Bertics PJ, Jarjour NN. Potential contribution of IL-7 to allergen-induced eosinophilic airway inflammation in asthma. THE JOURNAL OF IMMUNOLOGY 2009; 182:1404-10. [PMID: 19155487 DOI: 10.4049/jimmunol.182.3.1404] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The primary function of IL-7 is to promote maturation and survival of T cells. Through microarray expression analysis, we previously observed that human blood eosinophils express mRNA for IL-7R alpha (CD127) and its common gamma chain (CD132). The purpose of this study was to determine whether eosinophils have functional IL-7 receptors and to assess the potential contribution of IL-7 to eosinophilic airway inflammation by evaluating its presence in bronchoalveolar lavage (BAL) fluid of subjects with atopic asthma before and after segmental bronchoprovocation with allergen. Immunoblot analysis revealed that CD127 is present in highly purified human blood eosinophils. Furthermore, eosinophils responded to IL-7 with phosphorylation of STAT5, up-regulation of the activation marker CD69, and prolonged survival. Neutralization of GM-CSF but not IL-5 significantly blunted these functional responses, suggesting that IL-7 mediates its effects by promoting eosinophil release of autologous GM-CSF. Notably, the suppressive effect of anti-GM-CSF on STAT5 phosphorylation occurred within 10 min of eosinophil exposure to IL-7. Thus, IL-7 likely activates eosinophil release of preformed rather than newly synthesized GM-CSF. The biological relevance of IL-7 to eosinophilia in vivo was implicated in a study of airway allergen challenge in patients with allergic asthma. IL-7 concentrations in BAL fluid increased significantly 48 h after segmental allergen challenge and were highly correlated with BAL eosinophils (r = 0.7, p < 0.001). In conclusion, the airway response to allergen is associated with the generation of IL-7, which may contribute to airway inflammation by promoting enhanced eosinophil activation and survival. Activation of eosinophils is a novel function for IL-7.
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Affiliation(s)
- Elizabeth A B Kelly
- Section of Allergy, Pulmonary and Critical Care Medicine, Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792, USA.
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Velusamy T, Shetty P, Bhandary YP, Liu MC, Shetty S. Posttranscriptional Regulation of Urokinase Receptor Expression by Heterogeneous Nuclear Ribonuclear Protein C. Biochemistry 2008; 47:6508-17. [DOI: 10.1021/bi702338y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thirunavukkarasu Velusamy
- Texas Lung Injury Institute, Department of Specialty Care Services, The University of Texas Health Center at Tyler, 11937 U.S. Highway 271, Tyler, Texas 75708, and Department of Pharmacology, College of Pharmacy, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606
| | - Praveenkumar Shetty
- Texas Lung Injury Institute, Department of Specialty Care Services, The University of Texas Health Center at Tyler, 11937 U.S. Highway 271, Tyler, Texas 75708, and Department of Pharmacology, College of Pharmacy, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606
| | - Yashodhar P. Bhandary
- Texas Lung Injury Institute, Department of Specialty Care Services, The University of Texas Health Center at Tyler, 11937 U.S. Highway 271, Tyler, Texas 75708, and Department of Pharmacology, College of Pharmacy, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606
| | - Ming-Cheh Liu
- Texas Lung Injury Institute, Department of Specialty Care Services, The University of Texas Health Center at Tyler, 11937 U.S. Highway 271, Tyler, Texas 75708, and Department of Pharmacology, College of Pharmacy, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606
| | - Sreerama Shetty
- Texas Lung Injury Institute, Department of Specialty Care Services, The University of Texas Health Center at Tyler, 11937 U.S. Highway 271, Tyler, Texas 75708, and Department of Pharmacology, College of Pharmacy, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606
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hnRNP-R regulates the PMA-induced c-fos expression in retinal cells. Cell Mol Biol Lett 2008; 13:303-11. [PMID: 18197392 PMCID: PMC6275800 DOI: 10.2478/s11658-008-0002-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Accepted: 10/23/2007] [Indexed: 11/29/2022] Open
Abstract
This study focused on the function of hnRNP-R in the regulation of c-fos expression. We demonstrated that hnRNP-R accelerated the rise and decline phases of c-fos mRNAs and Fos proteins, allowing PMA to induce an augmented pulse response of c-fos expression. Then, we examined the role of the c-fos-derived AU-rich element (ARE) in hnRNP-R-regulated mRNA degradation. Studies with the ARE-GFP reporter gene showed that hnRNP-R significantly reduced the expression of GFP with an inserted ARE. Moreover, immunoprecipitation-RT-PCR analysis demonstrated that in R28 cells and rat retinal tissues, the c-fos mRNA was co-immunoprecipitated with hnRNP-R. These findings indicate that hnRNP-R regulates the c-fos expression in retinal cells, and that the ARE of c-fos mRNAs contributes to this regulation.
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Shen ZJ, Esnault S, Rosenthal LA, Szakaly RJ, Sorkness RL, Westmark PR, Sandor M, Malter JS. Pin1 regulates TGF-beta1 production by activated human and murine eosinophils and contributes to allergic lung fibrosis. J Clin Invest 2008; 118:479-90. [PMID: 18188456 DOI: 10.1172/jci32789] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Accepted: 10/31/2007] [Indexed: 12/21/2022] Open
Abstract
Eosinophilic inflammation is a cornerstone of chronic asthma that often culminates in subepithelial fibrosis with variable airway obstruction. Pulmonary eosinophils (Eos) are a predominant source of TGF-beta1, which drives fibroblast proliferation and extracellular matrix deposition. We investigated the regulation of TGF-beta1 and show here that the peptidyl-prolyl isomerase (PPIase) Pin1 promoted the stability of TGF-beta1 mRNA in human Eos. In addition, Pin1 regulated cytokine production by both in vitro and in vivo activated human Eos. We found that Pin1 interacted with both PKC-alpha and protein phosphatase 2A, which together control Pin1 isomerase activity. Pharmacologic blockade of Pin1 in a rat asthma model selectively reduced eosinophilic pulmonary inflammation, TGF-beta1 and collagen expression, and airway remodeling. Furthermore, chronically challenged Pin1(-/-) mice showed reduced peribronchiolar collagen deposition compared with wild-type controls. These data suggest that pharmacologic suppression of Pin1 may be a novel therapeutic option to prevent airway fibrosis in individuals with chronic asthma.
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Affiliation(s)
- Zhong-Jian Shen
- Waisman Center for Developmental Disabilities, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53705, USA
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Xiao PJ, Hu L, Li J, Lin W, Chen X, Xu P. NSSR1 is regulated in testes development and cryptorchidism and promotes the exon 5-included splicing of CREB transcripts. Mol Reprod Dev 2007; 74:1363-72. [PMID: 17427975 DOI: 10.1002/mrd.20719] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Neural salient serine/arginine rich protein 1 (NSSR1, alternatively SRp38) is a newly identified splicing factor that is highly expressed in neural and reproductive tissues. We showed that the expression of testicular NSSR1 increased significantly during mouse testes development. NSSR1 was mainly expressed in germ cells, but barely detected in Sertoli cells. Testicular NSSR1 was mostly phosphorylated and cytosolic in germ cells. In comparison, pituitary NSSR1 was mostly dephosphorylated and nuclear. In the cryptorchid testes, the dephosphorylated NSSR1 was significantly increased. RT-PCR analysis demonstrated that the alternative splicing of CREB and CREM genes was altered in the cryptorchid testes. In addition, CREB transcripts were associated with NSSR1 either in testes tissues or cultured GC-1 cells. Moreover, the studies with NSSR1 over-expression or silence demonstrated that NSSR1 promoted the exon 5 inclusion of CREB, indicating that NSSR1 is a new factor that regulates the alternative exon 5 inclusion of CREB transcripts. The findings for the first time provide the evidence indicating the potential importance of NSSR1 in testes development, spermatogenesis and cryptorchidism.
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Affiliation(s)
- Ping-Jie Xiao
- Laboratory of Genomic Physiology and State Key Laboratory of Medical Neurobiology, School of Life Sciences and Shanghai Medical College, Fudan University, Shanghai, China
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Abstract
A hallmark of tissue injury and repair is the turnover of extracellular matrix components. This review focuses on the role of the glycosaminoglycan hyaluronan in tissue injury and repair. Both the synthesis and degradation of extracellular matrix are critical contributors to tissue repair and remodeling. Fragmented hyaluronan accumulates during tissue injury and functions in ways distinct from the native polymer. There is accumulating evidence that hyaluronan degradation products can stimulate the expression of inflammatory genes by a variety of immune cells at the injury site. CD44 is the major cell-surface hyaluronan receptor and is required to clear hyaluronan degradation products produced during lung injury; impaired clearance of hyaluronan results in persistent inflammation. However, hyaluronan fragment stimulation of inflammatory gene expression is not dependent on CD44 in inflammatory macrophages. Instead, hyaluronan fragments utilize both Toll-like receptor (TLR) 4 and TLR2 to stimulate inflammatory genes in macrophages. Hyaluronan also is present on the cell surface of lung alveolar epithelial cells and provides protection against tissue damage by interacting with TLR2 and TLR4 on these parenchymal cells. The simple repeating structure of hyaluronan appears to be involved in a number of important aspects of noninfectious tissue injury and repair that are dependent on the size and location of the polymer as well as the interacting cells. Thus, the interactions between the endogenous matrix component hyaluronan and its signaling receptors initiate inflammatory responses, maintain structural cell integrity, and promote recovery from tissue injury.
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Affiliation(s)
- Dianhua Jiang
- Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Duke University School of Medicine, Durham, NC 27710, USA.
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40
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Esnault S, Fang Y, Kelly EAB, Sedgwick JB, Fine J, Malter JS, Jarjour NN. Circadian changes in granulocyte-macrophage colony-stimulating factor message in circulating eosinophils. Ann Allergy Asthma Immunol 2007; 98:75-82. [PMID: 17225724 DOI: 10.1016/s1081-1206(10)60863-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Granulocyte-macrophage colony-stimulating factor (GM-CSF), which stimulates eosinophil recruitment, activation, and survival, is expressed by activated eosinophils. Although eosinophil recruitment and enhanced survival have been associated with nocturnal asthma (NA), the contribution of GM-CSF to NA is unknown. OBJECTIVE To determine whether circulating eosinophil GM-CSF expression correlates with the symptoms of NA. METHODS The GM-CSF messenger RNA (mRNA) expression at 4 PM and 4 AM was determined by reverse-transcriptase polymerase chain reaction with Southern blot analysis in subjects with and without NA and in controls. RESULTS A total of 142 asthma subjects were screened for nocturnal asthma with 1-week home peak expiratory flow rate (PEFR) monitoring. Eleven subjects had NA (>20% diurnal variation in PEFR on 4 of 7 days), and 6 met the criteria for non-NA (<10% diurnal variation in PEFR on 7 of 7 days); 8 controls were studied. In subjects with NA, GM-CSF mRNA expression in circulating eosinophils increased 3-fold at 4 AM compared with 4 PM. Diurnal changes in GM-CSF mRNA expression were not detected in the non-NA and control groups. CONCLUSIONS Day-night variation in eosinophil GM-CSF expression is associated with circadian variation in airway function in asthma, a key manifestation of asthma severity.
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Affiliation(s)
- Stéphane Esnault
- Waisman Center for Developmental Disabilities, Madison, Wisconsin, USA
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Esnault S, Shen ZJ, Whitesel E, Malter JS. The peptidyl-prolyl isomerase Pin1 regulates granulocyte-macrophage colony-stimulating factor mRNA stability in T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2007; 177:6999-7006. [PMID: 17082615 DOI: 10.4049/jimmunol.177.10.6999] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cytokine production is associated with both the normal and pathologic inflammatory response to injury. Previous studies have shown that the immunosuppressants cyclosporin A or FK506, which interact with the peptidyl-propyl isomerases cyclophilin A and FK506-binding protein (FKBP12), respectively, block cytokine expression. A third member of the peptidyl-propyl isomerase family, Pin1 is expressed by immune and other cells. Pin1 has been implicated in cell cycle progression, is overexpressed in human tumors, and may rescue neurons from tau-associated degeneration. However, the role of Pin1 in the immune system remains largely unknown. In this study, we analyze the role of Pin1 in GM-CSF expression by human PBMC and CD4+ lymphocytes. We show that Pin1 isomerase activity is necessary for activation-dependent, GM-CSF mRNA stabilization, accumulation, and protein secretion, but not non-AU-rich elements containing cytokine mRNAs, including TGF-beta and IL-4. Mechanistically, Pin1 mediated the association of the AU-rich element-binding protein, AUF1, with GM-CSF mRNA, which determined the rate of decay by the exosome.
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Affiliation(s)
- Stephane Esnault
- Waisman Center for Developmental Disabilities, Department of Pathology and Laboratory Medicine, University of Wisconsin School of Medicine, Madison, WI 53705, USA
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Kirino Y, Takeno M, Murakami S, Kobayashi M, Kobayashi H, Miura K, Ideguchi H, Ohno S, Ueda A, Ishigatsubo Y. Tumor necrosis factor α acceleration of inflammatory responses by down-regulating heme oxygenase 1 in human peripheral monocytes. ACTA ACUST UNITED AC 2007; 56:464-75. [PMID: 17265482 DOI: 10.1002/art.22370] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To examine the interaction between heme oxygenase 1 (HO-1), a stress-induced antiinflammatory protein, and tumor necrosis factor alpha (TNFalpha) in human peripheral blood monocytes. METHODS Peripheral blood mononuclear cells (PBMCs) were obtained from healthy donors or from patients with rheumatoid arthritis (RA) receiving the anti-tumor necrosis factor alpha (anti-TNFalpha) monoclonal antibody infliximab. CD14+ cells were isolated by magnetic cell sorting, cultured with TNFalpha or auranofin, and transfected with a plasmid encoding HO-1 or an HO-1-specific small interfering RNA vector. Protein and messenger RNA (mRNA) levels were examined by immunoblotting and real-time polymerase chain reaction. Cytokine levels in culture supernatants were measured by enzyme-linked immunosorbent assay. HO-1 gene transcription was evaluated using a luciferase reporter gene assay. Actinomycin D and cycloheximide were used to monitor the stability of mRNA and protein. RESULTS HO-1 is constitutively expressed by CD14+ PBMCs from healthy donors. TNFalpha suppressed HO-1 expression by accelerating the decay of mRNA without affecting gene transcription or protein stability. Forced expression or selective knock-down of the HO-1 gene expression resulted in down-regulation or up-regulation, respectively, of proinflammatory cytokine synthesis by monocytes. Treatment with infliximab significantly increased HO-1 mRNA levels and reduced TNFalpha synthesis by PBMCs from RA patients. CONCLUSION TNFalpha accelerated inflammatory responses by down-regulating HO-1 expression in human monocytes. TNF antagonists may block this TNF-dependent suppression of HO-1 expression, resulting in an amelioration of inflammation.
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Affiliation(s)
- Yohei Kirino
- Yokohama City University, Graduate School of Medicine, Yokohama, Japan
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43
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Yohe HC, O'Hara KA, Hunt JA, Kitzmiller TJ, Wood SG, Bement JL, Bement WJ, Szakacs JG, Wrighton SA, Jacobs JM, Kostrubsky V, Sinclair PR, Sinclair JF. Involvement of Toll-like receptor 4 in acetaminophen hepatotoxicity. Am J Physiol Gastrointest Liver Physiol 2006; 290:G1269-79. [PMID: 16439473 DOI: 10.1152/ajpgi.00239.2005] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The objective of this study was to determine whether Toll-like receptor 4 (TLR4) has a role in alcohol-mediated acetaminophen (APAP) hepatotoxicity. TLR4 is involved in the inflammatory response to endotoxin. Others have found that ethanol-mediated liver disease is decreased in C3H/HeJ mice, which have a mutated TLR4 resulting in a decreased response to endotoxin compared with endotoxin-responsive mice. In the present study, short-term (1 wk) pretreatment with ethanol plus isopentanol, the predominant alcohols in alcoholic beverages, caused no histologically observed liver damage in either C3H/HeJ mice or endotoxin-responsive C3H/HeN mice, despite an increase in nitrotyrosine levels in the livers of C3H/HeN mice. In C3H/HeN mice pretreated with the alcohols, subsequent exposure to APAP caused a transient decrease in liver nitrotyrosine formation, possibly due to competitive interaction of peroxynitrite with APAP producing 3-nitroacetaminophen. Treatment with APAP alone resulted in steatosis in addition to congestion and necrosis in both C3H/HeN and C3H/HeJ mice, but the effects were more severe in endotoxin-responsive C3H/HeN mice. In alcohol-pretreated endotoxin-responsive C3H/HeN mice, subsequent exposure to APAP resulted in further increases in liver damage, including severe steatosis, associated with elevated plasma levels of TNF-alpha. In contrast, alcohol pretreatment of C3H/HeJ mice caused little to no increase in APAP hepatotoxicity and no increase in plasma TNF-alpha. Portal blood endotoxin levels were very low and were not detectably elevated by any of the treatments. In conclusion, this study implicates a role of TLR4 in APAP-mediated hepatotoxicity.
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Affiliation(s)
- Herbert C Yohe
- Veterans Administration Medical Center, White River Junction, VT 05009, USA.
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Shen ZJ, Esnault S, Malter JS. The peptidyl-prolyl isomerase Pin1 regulates the stability of granulocyte-macrophage colony-stimulating factor mRNA in activated eosinophils. Nat Immunol 2005; 6:1280-7. [PMID: 16273101 DOI: 10.1038/ni1266] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2005] [Accepted: 08/30/2005] [Indexed: 01/15/2023]
Abstract
The infiltration, accumulation and degranulation of eosinophils in the lung represents a hallmark of active asthma. In vivo or in vitro eosinophil activation triggers the secretion of the antiapoptotic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF). We now identify Pin1, a cis-trans isomerase, as an essential component of the ribonucleoprotein complex responsible for GM-CSF mRNA stabilization, cytokine secretion and the survival of activated eosinophils. Pin1 regulated the association of the AU-rich element-binding proteins AUF1 and hnRNP C with GM-CSF mRNA, accelerating or slowing decay, respectively. These data indicate Pin1 is a key mediator of GM-CSF production.
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Affiliation(s)
- Zhong-Jian Shen
- The Waisman Center for Developmental Disabilities, the Department of Pathology and Laboratory Medicine, University of Wisconsin School of Medicine, Madison, Wisconsin 53705, USA
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45
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Chang X, Yamada R, Suzuki A, Kochi Y, Sawada T, Yamamoto K. Citrullination of fibronectin in rheumatoid arthritis synovial tissue. Rheumatology (Oxford) 2005; 44:1374-82. [PMID: 16105911 DOI: 10.1093/rheumatology/kei023] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Citrullination, catalysed by peptidylarginine deiminase (PAD), is the post-translational modification of peptidylarginine to citrulline, which is intimately involved in the pathogenesis of rheumatoid arthritis (RA). Fibronectin (Fn), a large glycoprotein, is expressed at high levels in arthritic joints and it mediates various physiological processes through interactions with cell-surface integrin receptors and growth factors. We investigated the citrullination of Fn and its potential contribution to the pathogenesis of RA. METHODS We localized Fn expression and citrullination in RA synovial tissue by immunohistochemistry, immunoprecipitation and western blotting. We also determined levels of citrullinated Fn in plasma from RA patients using sandwich enzyme-linked immunosorbent assay (ELISA). After incubating Fn with rabbit skeletal muscle PAD, we examined the binding ability of citrullinated Fn to vascular endothelial growth factor (VEGF) and integrin beta1 using a solid-phase receptor binding assay as well as the effect of the citrullinated Fn on apoptosis using cultured HL-60 cells. RESULTS Immunohistochemistry and western blotting analysis indicated that Fn formed extracellular aggregates that were specifically citrullinated in RA synovial tissue. No Fn deposits were observed in synovial tissues of osteoarthritis (OA). Sandwich ELISA detected higher levels of citrullinated Fn in plasma from patients with RA than from healthy controls or those with systemic lupus erythematosus. Following citrullination in vitro, the affinity of Fn for VEGF increased, but binding activity to integrin beta1 decreased and Fn no longer stimulated the apoptosis of monocytes induced from cultured HL-60 cells. CONCLUSIONS Our results suggest that the citrullination of Fn is a specific event for RA synovium, although others have detected citrullinated total proteins in inflamed synovial tissue of RA and non-RA patients. Citrullination of Fn could alter interactions between Fn and its receptors and growth factors, consequently contributing to mechanisms of RA pathogenesis such as perturbed angiogenesis and apoptosis.
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Affiliation(s)
- X Chang
- The Laboratory for Rheumatic Diseases, SNP Research Center, The Institute of Physical and Chemical Research (RIKEN), 1-7-22 Suehiro, Yokohama, Kanagawa, 230-0045, Japan.
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Zhang A, Liu X, Cogan JG, Fuerst MD, Polikandriotis JA, Kelm RJ, Strauch AR. YB-1 coordinates vascular smooth muscle alpha-actin gene activation by transforming growth factor beta1 and thrombin during differentiation of human pulmonary myofibroblasts. Mol Biol Cell 2005; 16:4931-40. [PMID: 16093352 PMCID: PMC1243245 DOI: 10.1091/mbc.e05-03-0216] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Profibrotic regulatory mechanisms for tissue repair after traumatic injury have developed under strong evolutionary pressure to rapidly stanch blood loss and close open wounds. We have examined the roles played by two profibrotic mediators, transforming growth factor beta1 (TGFbeta1) and thrombin, in directing expression of the vascular smooth muscle alpha-actin (SMalphaA) gene, an important determinant of myofibroblast differentiation and early protein marker for stromal cell response to tissue injury. TGFbeta1 is a well known transcriptional activator of the SMalphaA gene in myofibroblasts. In contrast, thrombin independently elevates SMalphaA expression in human pulmonary myofibroblasts at the posttranscriptional level. A common feature of SMalphaA up-regulation mediated by thrombin and TGFbeta1 is the involvement of the cold shock domain protein YB-1, a potent repressor of SMalphaA gene transcription in human fibroblasts that also binds mRNA and regulates translational efficiency. YB-1 dissociates from SMalphaA enhancer DNA in the presence of TGFbeta1 or its Smad 2, 3, and 4 coregulatory mediators. Thrombin does not effect SMalphaA gene transcription but rather displaces YB-1 from SMalphaA exon 3 coding sequences previously shown to be required for mRNA translational silencing. The release of YB-1 from promoter DNA coupled with its ability to bind RNA and shuttle between the nucleus and cytoplasm is suggestive of a regulatory loop for coordinating SMalphaA gene output in human pulmonary myofibroblasts at both the transcriptional and translational levels. This loop may help restrict organ-destructive remodeling due to excessive myofibroblast differentiation.
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Affiliation(s)
- Aiwen Zhang
- Department of Physiology and Cell Biology, The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University College of Medicine and Public Health, Columbus, OH 43210, USA
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Pullmann R, Juhaszova M, López de Silanes I, Kawai T, Mazan-Mamczarz K, Halushka MK, Gorospe M. Enhanced proliferation of cultured human vascular smooth muscle cells linked to increased function of RNA-binding protein HuR. J Biol Chem 2005; 280:22819-26. [PMID: 15824116 PMCID: PMC1350862 DOI: 10.1074/jbc.m501106200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In dividing cells, the RNA-binding protein HuR associates with and stabilizes labile mRNAs encoding proliferative proteins, events that are linked to the increased cytoplasmic presence of HuR. Here, assessment of HuR levels in various vascular pathologies (intimal hyperplasia, atherosclerosis and neointimal proliferation, sclerosis of arterialized saphenous venous graft, and fibromuscular dysplasia) revealed a distinct increase in HuR expression and cytoplasmic abundance within the intima and neointima layers. On the basis of these observations, we postulated a role for HuR in promoting the proliferation of vascular smooth muscle cells. To test this hypothesis directly, we investigated the expression, subcellular localization, and proliferative influence of HuR in human vascular smooth muscle cells (hVSMCs). Treatment of hVSMCs with platelet-derived growth factor increased HuR levels in the cytoplasm, thereby influencing the expression of metabolic, proliferative, and structural genes. Importantly, knockdown of HuR expression by using RNA interference caused a reduction of hVSMC proliferation, both basally and following platelet-derived growth factor treatment. We propose that HuR contributes to regulating hVSMC growth and homeostasis in pathologies associated with vascular smooth muscle proliferation.
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Affiliation(s)
- Rudolf Pullmann
- Laboratory of Cellular and Molecular Biology and Laboratory of Cardiovascular Sciences, NIA-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
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48
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Lal A, Kawai T, Yang X, Mazan-Mamczarz K, Gorospe M. Antiapoptotic function of RNA-binding protein HuR effected through prothymosin alpha. EMBO J 2005; 24:1852-62. [PMID: 15861128 PMCID: PMC1142594 DOI: 10.1038/sj.emboj.7600661] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Accepted: 04/05/2005] [Indexed: 11/08/2022] Open
Abstract
We report the antiapoptotic effect of RNA-binding protein HuR, a critical regulator of the post-transcriptional fate of target transcripts. Among the most prominent mRNAs complexing with HuR is that encoding prothymosin alpha (ProTalpha), an inhibitor of the apoptosome. In HeLa cells, treatment with the apoptotic stimulus ultraviolet light (UVC) triggered the mobilization of ProTalpha mRNA to the cytoplasm and onto heavier polysomes, where its association with HuR increased dramatically. Analysis of a chimeric ProTalpha mRNA directly implicated HuR in regulating ProTalpha production: ProTalpha translation and cytoplasmic concentration increased in HuR-overexpressing cells and declined in cells in which HuR levels were lowered by RNA interference. Importantly, the antiapoptotic influence engendered by HuR was vitally dependent on ProTalpha expression, since use of oligomers that blocked ProTalpha translation abrogated the protective effect of HuR. Together, our data support a regulatory scheme whereby HuR binds the ProTalpha mRNA, elevates its cytoplasmic abundance and translation, and thereby elicits an antiapoptotic program.
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Affiliation(s)
- Ashish Lal
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Tomoko Kawai
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Xiaoling Yang
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Krystyna Mazan-Mamczarz
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Myriam Gorospe
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
- Box 12, LCMB, NIA-IRP, NIH 5600 Nathan Shock Drive, Baltimore, MD 21224, USA. Tel.: +1 410 558 8443; Fax: +1 410 558 8386; E-mail:
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49
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Ammit AJ. The role of mRNA stability in airway remodelling. Pulm Pharmacol Ther 2005; 18:405-15. [PMID: 16179216 DOI: 10.1016/j.pupt.2005.03.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2004] [Revised: 02/09/2005] [Accepted: 03/03/2005] [Indexed: 11/30/2022]
Abstract
As a consequence of long-term exposure to inflammatory mediators, the airways of asthmatics become remodelled. Airway fibrosis becomes apparent, with thickening of the lamina recticularis and increased interstitial matrix deposition being typical features of an asthmatic airway. Mucus hypersecretion occurs, airway smooth muscle mass is increased and neovascularization is evident in the subepithelial mucosa. As development of a remodelled airway is correlated with deterioration of lung function in asthmatics, there is an urgent need for therapies that reduce airway inflammation and reverse structural changes in a remodelled airway. However, in order to design efficacious anti-remodelling agents we first need a greater understanding of the molecular mechanism/s underlying the development of airway remodelling. To date, however, most studies have primarily focused on the transcriptional regulation of genes that promote airway remodelling. Post-transcriptional mechanisms, such as control of mRNA stability, remain largely unexplored. Levels of cellular mRNA transcripts are regulated by controlling the rate at which the mRNA decays, thus investigation into the mechanisms underlying mRNA stability in asthma are of critical importance. Therefore, this review will present an overview of the control of mRNA stability and examine how mRNA stability may play a role in the development of airway remodelling in asthma.
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Affiliation(s)
- Alaina J Ammit
- Respiratory Research Group, Faculty of Pharmacy, University of Sydney, NSW 2006, Australia.
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Peng Q, Lai D, Nguyen TTB, Chan V, Matsuda T, Hirst SJ. Multiple beta 1 integrins mediate enhancement of human airway smooth muscle cytokine secretion by fibronectin and type I collagen. THE JOURNAL OF IMMUNOLOGY 2005; 174:2258-64. [PMID: 15699160 DOI: 10.4049/jimmunol.174.4.2258] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Altered airway smooth muscle (ASM) function and enrichment of the extracellular matrix (ECM) with interstitial collagen and fibronectin are major pathological features of airway remodeling in asthma. We have previously shown that these ECM components confer enhanced ASM proliferation in vitro, but their action on its newly characterized secretory function is unknown. Here, we examined the effects of fibronectin and collagen types I, III, and V on IL-1beta-dependent secretory responses of human ASM cells, and characterized the involvement of specific integrins. Cytokine production (eotaxin, RANTES, and GM-CSF) was evaluated by ELISA, RT-PCR, and flow cytometry. Function-blocking integrin mAbs and RGD (Arg-Gly-Asp)-blocking peptides were used to identify integrin involvement. IL-1beta-dependent release of eotaxin, RANTES, and GM-CSF was enhanced by fibronectin and by fibrillar and monomeric type I collagen, with similar changes in mRNA abundance. Collagen types III and V had no effect on eotaxin or RANTES release but did modulate GM-CSF. Analogous changes in intracellular cytokine accumulation were found, but in <25% of the total ASM cell population. Function-blocking Ab and RGD peptide studies revealed that alpha2beta1, alpha5beta1, alphavbeta1, and alphavbeta3 integrins were required for up-regulation of IL-1beta-dependent ASM secretory responses by fibronectin, while alpha2beta1 was an important transducer for type I collagen. Thus, fibronectin and type I collagen enhance IL-1beta-dependent ASM secretory responses through a beta1 integrin-dependent mechanism. Enhancement of cytokine release from ASM by these ECM components may contribute to airway wall inflammation and remodeling in asthma.
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Affiliation(s)
- Qi Peng
- Department of Asthma, Allergy and Respiratory Science, The Guy's, King's and St. Thomas' School of Medicine, King's College London, Guy's Hospital Campus, London, United Kingdom
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