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Balaguer N, Moreno I, Herrero M, González M, Simón C, Vilella F. Heterogeneous nuclear ribonucleoprotein C1 may control miR-30d levels in endometrial exosomes affecting early embryo implantation. Mol Hum Reprod 2019; 24:411-425. [PMID: 29846695 DOI: 10.1093/molehr/gay026] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/28/2018] [Indexed: 12/19/2022] Open
Abstract
STUDY QUESTION Is there a specific mechanism to load the microRNA (miRNA), hsa-miR-30d, into exosomes to facilitate maternal communication with preimplantation embryos? SUMMARY ANSWER The heterogeneous nuclear ribonucleoprotein C1 (hnRNPC1) is involved in the internalization of endometrial miR-30d into exosomes to prepare for its subsequent incorporation into trophectoderm cells. WHAT IS KNOWN ALREADY Our group previously described a novel cell-to-cell communication mechanism involving the delivery of endometrial miRNAs from the maternal endometrium to the trophectoderm cells of preimplantation embryos. Specifically, human endometrial miR-30d is taken up by murine blastocysts causing the overexpression of certain genes involved in embryonic adhesion (Itb3, Itga7 and Cdh5) increasing embryo adhesion rates. STUDY DESIGN, SIZE, DURATION Transfer of maternal miR-30d to preimplantation embryos was confirmed by co-culture of wild-type (WT) and miR-30d knockout (KO) murine embryos with primary cultures of human endometrial epithelial cells (hEECs) in which mir-30d was labeled with specific Molecular Beacon (MB) or SmartFlare probes. Potential molecules responsible for the miR-30d loading into exosomes were purified by pull-down analysis with a biotinylated form of miR-30d on protein lysates from human endometrial exosomes, identified using mass spectrometry and assessed by flow cytometry, western blotting and co-localization studies. The role of hnRNPC1 in the miR-30d loading and transportation was interrogated by quantification of this miRNA in exosomes isolated from endometrial cells in which hnRNPC1 was transiently silenced using small interference RNA. Finally, the transfer of miR-30d to WT and KO embryos was assessed upon co-culture with sihnRNPC1 transfected cells. PARTICIPANTS/MATERIALS, SETTING, METHODS Murine embryos from miR-30d WT and KO mice, (strain MirC26tm1Mtm/Mmjax), were obtained by oviduct flushing of superovulated females. Endometrial Exosomes were purified by ultracentrifugation of supernatants from primary cultures of hEECs or Ishikawa cells. MB and Smartflare miR-30d probes were detected by confocal and/or transmission electron microscopy (TEM). hEECs and exosomes derived from them were subjected to pull-down with a biotinylated form of miR-30d. Captured proteins were identified by mass spectrometry (MS/MS). Western blotting was performed to detect hnRNPC1 and CYR61 in whole lysates, subcellular fractions and secreted vesicles from hEECs. Co-localization studies of the selected proteins with the exosomal marker CD63 were performed. FACS analysis was carried out to determine the presence of hnRNPC1 inside exosomes. Silencing of hnRNPC1 was conducted in the Ishikawa Cell Line with the Smart Pool Accell HNRNPC siRNA at a final concentration of 50 nM. RT-qPCRs were done to determine the messenger levels of miR-30d in cells and exosomes. Co-cultures of WT and KO embryos were established with Ishikawa cells double-transfected with sihnRPNC1 and MB probes. MAIN RESULTS AND THE ROLE OF CHANCE MS/MS analysis allowed us to identify hnRNPC1 as a possible protein to influence miR-30d loading into exosomes. Co-localization studies of hnRNPC1 with CD63 and FACS analyses suggested the presence of hnRNPC1 inside exosomes. Silencing of hnRNPC1 in Ishikawa cells resulted in a sharp decrease of the levels of miR-30d in both epithelial-like cells (P = 0.0001) and exosomes (P = 0.0152), suggesting its potential role in miR-30d biogenesis and transfer. Co-culture assays of miR-30d KO embryos with sihnRNPC1 hEECs revealed a decrease in embryo-miR-30d acquisition during the adhesion and invasion stages. In turn, transient silencing of hnRNPC1 results in a significant decrease of blastocyst adhesion compared to mock transfection conditions using Block-it, in both WT [Mean ± SD; 67 ± 10.0% vs. 38 ± 8.5%(P = 0.0006)] and miR-30d KO embryos [Mean ± SD; 50 ± 11.5% vs. 26 ± 8.8% (P = 0.0029) (n = 2); 14 embryos transferred per condition tested]. LARGE-SCALE DATA MS/MS data are available via ProteomeXchange with identifier PXD008773. LIMITATIONS, REASONS FOR CAUTION The Ishikawa Cell Line was used as a model of hEECs in silencing experiments due to the low survival rates of primary hEECs after transfection. WIDER IMPLICATIONS OF THE FINDINGS The data show that hnRNPC1 may be involved in the internalization of miR-30d inside exosomes. The decreased rates of embryo adhesion in endometrial epithelial-like cells transiently silenced with sihnRNPC1evidence that hnRNPC1 could be an important player in the maternal-embryo communication established in the early stages of implantation. STUDY FUNDING AND COMPETING INTEREST(S) This work was supported by the Miguel Servet Program Type I of Instituto de Salud Carlos III [CP13/00038]; FIS project [PI14/00545] to F.V.; the 'Atracció de Talent' Program from VLC-CAMPUS [UV-INV-PREDOC14-178329 to NB]; a Torres-Quevedo grant (PTQ-13-06133) by the Spanish Ministry of Economy and Competitiveness to IM and MINECO/FEDER Grant [SAF2015-67154-R] to C.S. The authors declare there is no conflict of interest.
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Affiliation(s)
- N Balaguer
- Department of Pediatrics, Obstetrics and Gynecology, School of Medicine, University of Valencia, Valencia, Spain
| | - I Moreno
- Department of Basic Research, Igenomix, S.L. Parque Tecnológico de Paterna, Valencia, Spain.,Department of Obstetrics and Gynecology, School of Medicine, Stanford University, CA, USA
| | - M Herrero
- Department of Basic Research, Igenomix, S.L. Parque Tecnológico de Paterna, Valencia, Spain
| | - M González
- Department of Basic Research, Igenomix, S.L. Parque Tecnológico de Paterna, Valencia, Spain
| | - C Simón
- Department of Pediatrics, Obstetrics and Gynecology, School of Medicine, University of Valencia, Valencia, Spain.,Department of Basic Research, Igenomix, S.L. Parque Tecnológico de Paterna, Valencia, Spain.,Department of Obstetrics and Gynecology, School of Medicine, Stanford University, CA, USA.,Department of Reproductive Medicine, Igenomix Foundation, Instituto de Investigación Sanitaria Hospital Clínico (INCLIVA), Valencia, Spain
| | - F Vilella
- Department of Obstetrics and Gynecology, School of Medicine, Stanford University, CA, USA.,Department of Reproductive Medicine, Igenomix Foundation, Instituto de Investigación Sanitaria Hospital Clínico (INCLIVA), Valencia, Spain
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Rastogi M, Sharma N, Singh SK. Flavivirus NS1: a multifaceted enigmatic viral protein. Virol J 2016; 13:131. [PMID: 27473856 PMCID: PMC4966872 DOI: 10.1186/s12985-016-0590-7] [Citation(s) in RCA: 161] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 07/26/2016] [Indexed: 12/31/2022] Open
Abstract
Flaviviruses are emerging arthropod-borne viruses representing an immense global health problem. The prominent viruses of this group include dengue virus, yellow fever virus, Japanese encephalitis virus, West Nile virus tick borne encephalitis virus and Zika Virus. These are endemic in many parts of the world. They are responsible for the illness ranging from mild flu like symptoms to severe hemorrhagic, neurologic and cognitive manifestations leading to death. NS1 is a highly conserved non-structural protein among flaviviruses, which exist in diverse forms. The intracellular dimer form of NS1 plays role in genome replication, whereas, the secreted hexamer plays role in immune evasion. The secreted NS1 has been identified as a potential diagnostic marker for early detection of the infections caused by flaviviruses. In addition to the diagnostic marker, the importance of NS1 has been reported in the development of therapeutics. NS1 based subunit vaccines are at various stages of development. The structural details and diverse functions of NS1 have been discussed in detail in this review.
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Affiliation(s)
- Meghana Rastogi
- Institute of Medical Sciences (IMS), Laboratory of Human Molecular Virology & Immunology, Molecular Biology Unit, Faculty of Medicine, Banaras Hindu University, Varanasi, 221005, India
| | - Nikhil Sharma
- Laboratory of Neurovirology and Inflammation Biology, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Hyderabad, 500007, India
| | - Sunit Kumar Singh
- Institute of Medical Sciences (IMS), Laboratory of Human Molecular Virology & Immunology, Molecular Biology Unit, Faculty of Medicine, Banaras Hindu University, Varanasi, 221005, India.
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Dhanjal S, Kajitani N, Glahder J, Mossberg AK, Johansson C, Schwartz S. Heterogeneous Nuclear Ribonucleoprotein C Proteins Interact with the Human Papillomavirus Type 16 (HPV16) Early 3'-Untranslated Region and Alleviate Suppression of HPV16 Late L1 mRNA Splicing. J Biol Chem 2015; 290:13354-71. [PMID: 25878250 DOI: 10.1074/jbc.m115.638098] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Indexed: 01/09/2023] Open
Abstract
In order to identify cellular factors that regulate human papillomavirus type 16 (HPV16) gene expression, cervical cancer cells permissive for HPV16 late gene expression were identified and characterized. These cells either contained a novel spliced variant of the L1 mRNAs that bypassed the suppressed HPV16 late, 5'-splice site SD3632; produced elevated levels of RNA-binding proteins SRSF1 (ASF/SF2), SRSF9 (SRp30c), and HuR that are known to regulate HPV16 late gene expression; or were shown by a gene expression array analysis to overexpress the RALYL RNA-binding protein of the heterogeneous nuclear ribonucleoprotein C (hnRNP C) family. Overexpression of RALYL or hnRNP C1 induced HPV16 late gene expression from HPV16 subgenomic plasmids and from episomal forms of the full-length HPV16 genome. This induction was dependent on the HPV16 early untranslated region. Binding of hnRNP C1 to the HPV16 early, untranslated region activated HPV16 late 5'-splice site SD3632 and resulted in production of HPV16 L1 mRNAs. Our results suggested that hnRNP C1 controls HPV16 late gene expression.
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Affiliation(s)
- Soniya Dhanjal
- From the Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden
| | - Naoko Kajitani
- From the Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden
| | - Jacob Glahder
- From the Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden
| | - Ann-Kristin Mossberg
- From the Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden
| | - Cecilia Johansson
- From the Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden
| | - Stefan Schwartz
- From the Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden
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Dechtawewat T, Songprakhon P, Limjindaporn T, Puttikhunt C, Kasinrerk W, Saitornuang S, Yenchitsomanus PT, Noisakran S. Role of human heterogeneous nuclear ribonucleoprotein C1/C2 in dengue virus replication. Virol J 2015; 12:14. [PMID: 25890165 PMCID: PMC4351676 DOI: 10.1186/s12985-014-0219-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 11/27/2014] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Host and viral proteins are involved in dengue virus (DENV) replication. Heterogeneous ribonucleoprotein (hnRNP) C1/C2 are abundant host cellular proteins that exhibit RNA binding activity and play important roles in the replication of positive-strand RNA viruses such as poliovirus and hepatitis C virus. hnRNP C1/C2 have previously been shown to interact with vimentin and viral NS1 in DENV-infected cells; however, their functional role in DENV replication is not clearly understood. In the present study, we investigated the role of hnRNP C1/C2 in DENV replication by using an in vitro model of DENV infection in a hepatocyte cell line (Huh7) and siRNA-mediated knockdown of hnRNP C1/C2. METHODS Huh7 cells were transfected with hnRNP C1/C2-specific siRNA or irrelevant siRNA (control) followed by infection with DENV. Mock and DENV-infected knockdown cells were processed for immunoprecipitation using hnRNP C1/C2-specific antibody or their isotype-matched control antibody. The immunoprecipitated samples were subjected to RNA extraction and reverse transcriptase polymerase chain reaction (RT-PCR) for detection of DENV RNA. In addition, the knockdown cells harvested at varying time points after the infection were assessed for cell viability, cell proliferation, percentage of DENV infection, amount of viral RNA, and viral E and NS1 expression. Culture supernatants were subjected to focus forming unit assays to determine titers of infectious DENV. DENV luciferase reporter assay was also set up to determine viral translation. RESULTS Immunoprecipitation with the anti-hnRNP C1/C2 antibody and subsequent RT-PCR revealed the presence of DENV RNA in the immunoprecipitated complex containing hnRNP C1/C2 proteins. Transfection with hnRNP C1/C2-specific siRNA resulted in a significant reduction of hnRNP C1/C2 mRNA and protein levels but did not induce cell death during DENV infection. The reduced hnRNP C1/C2 expression decreased the percentage of DENV antigen-positive cells as well as the amount of DENV RNA and the relative levels of DENV E and NS1 proteins; however, it had no direct effect on DENV translation. In addition, a significant reduction of DENV titers was observed in the supernatant from DENV-infected cells following the knockdown of hnRNP C1/C2. CONCLUSIONS Our findings suggest that hnRNP C1/C2 is involved in DENV replication at the stage of viral RNA synthesis.
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Affiliation(s)
- Thanyaporn Dechtawewat
- Division of Molecular Medicine, Office of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
- Graduate Program in Immunology, Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Pucharee Songprakhon
- Division of Molecular Medicine, Office of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Thawornchai Limjindaporn
- Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Chunya Puttikhunt
- Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok, 10700, Thailand.
- Division of Dengue Hemorrhagic Fever Research Unit, Office of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Watchara Kasinrerk
- Division of Clinical Immunology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand.
- Biomedical Technology Research Center, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Chiang Mai, 50200, Thailand.
| | - Sawanan Saitornuang
- Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok, 10700, Thailand.
- Division of Dengue Hemorrhagic Fever Research Unit, Office of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Pa-Thai Yenchitsomanus
- Division of Molecular Medicine, Office of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Sansanee Noisakran
- Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok, 10700, Thailand.
- Division of Dengue Hemorrhagic Fever Research Unit, Office of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
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Huang Q, Zhang J, Peng S, Du M, Ow S, Pu H, Pan C, Shen H. Proteomic analysis of perfluorooctane sulfonate-induced apoptosis in human hepatic cells using the iTRAQ technique. J Appl Toxicol 2013; 34:1342-51. [PMID: 24301089 DOI: 10.1002/jat.2963] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 10/10/2013] [Accepted: 10/14/2013] [Indexed: 01/09/2023]
Abstract
Perfluorooctane sulfonate (PFOS) is one of the most commonly used perfluorinated compounds, whose environmental exposure has been associated with a number of adverse health outcomes. However, the molecular mechanisms involved in PFOS toxicity are still not well elucidated. In the present study, we applied iTRAQ labeling quantitative proteomic technology to investigate the differential protein expression profiles of non-tumor human hepatic cells (L-02) exposed to PFOS. A total of 18 proteins were differentially expressed in a dose-dependent manner in PFOS-treated cells versus the control. Among these, 11 proteins were up-regulated and 7 were down-regulated. Gene ontology analysis indicated that PFOS would exert toxic effects on L-02 cells by affecting multiple biological processes, including protein biosynthesis and degradation, mRNA processing and splicing, transcription, signal transduction and transport. Furthermore, the proteomic results especially proposed that the inhibition of HNRNPC, HUWE1 and UBQLN1, as well as the induction of PAF1 is involved in the activation of the p53 and c-myc signaling pathways, which then trigger the apoptotic process in L-02 cells exposed to PFOS. Overall, these data will aid our understanding of the mechanisms responsible for PFOS-mediated hepatotoxicity, and develop useful biomarkers for monitoring and evaluating PFOS contamination in the environment.
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Affiliation(s)
- Qingyu Huang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
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Huang Q, Zhang J, Martin FL, Peng S, Tian M, Mu X, Shen H. Perfluorooctanoic acid induces apoptosis through the p53-dependent mitochondrial pathway in human hepatic cells: a proteomic study. Toxicol Lett 2013; 223:211-20. [PMID: 24035753 DOI: 10.1016/j.toxlet.2013.09.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 08/28/2013] [Accepted: 09/04/2013] [Indexed: 12/23/2022]
Abstract
Perfluorooctanoic acid (PFOA) is one of the most commonly used perfluorinated compounds, and exposure to it has been associated with a number of adverse health effects. However, the molecular mechanisms involved in PFOA toxicity are still not well characterized. In the present study, flow cytometry analysis revealed that PFOA induced oxidative stress, cell cycle arrest and apoptosis in human non-tumor hepatic cells (L-02). Furthermore, we investigated the alterations in protein profile within L-02 cells exposed to PFOA, aiming to explore the mechanisms underlying PFOA hepatotoxicity on the proteome level. Of the 28 proteins showing significant differential expression in response to PFOA, 24 were down-regulated and 4 were up-regulated. This proteomic study proposed that the inhibition of some proteins, including GRP78, HSP27, CTSD and hnRNPC may be involved in the activation of p53, which consequently triggered the apoptotic process in L-02 cells. Induction of apoptosis via the p53-dependent mitochondrial pathway is further suggested as one of the key toxicological events occurring in L-02 cells under PFOA stress. We hope these data will shed new light on the molecular mechanisms responsible for PFOA-mediated toxicity in human liver cells, and from such studies useful biomarkers indicative of PFOA exposure could be developed.
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Affiliation(s)
- Qingyu Huang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China
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Jung EJ, Lee SY, Kim CW. Proteomic analysis of novel targets associated with TrkA-mediated tyrosine phosphorylation signaling pathways in SK-N-MC neuroblastoma cells. Proteomics 2013; 13:355-67. [PMID: 23319303 PMCID: PMC3580882 DOI: 10.1002/pmic.201200251] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/28/2012] [Accepted: 10/25/2012] [Indexed: 02/04/2023]
Abstract
Tropomyosin-related kinase A (TrkA) is a receptor-type protein tyrosine kinase and exploits pleiotypic roles via nerve growth factor (NGF)-dependent or NGF-independent mechanisms in various cell types. Here, we showed that the inhibition of TrkA activity by GW441756 resulted in the suppression of tyrosine phosphorylation of cellular proteins including extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK). To find novel targets associated with TrkA-mediated tyrosine phosphorylation signaling pathways, we investigated GW441756 effects on TrkA-dependent targets in SK-N-MC neuroblastoma cells by proteomic analysis. The major TrkA-dependent protein spots controlled by GW441756 were determined by PDQuest image analysis, identified by MALDI-TOF MS and MALDI-TOF/TOF MS/MS, and verified by 2DE/Western blot analysis. Thus, we found that most of the identified protein spots were modified forms in a normal condition, and their modifications were regulated by TrkA activity. Especially, our results demonstrated that the modifications of α-tubulin and heterogeneous nuclear ribonucleoproteins C1/C2 (hnRNP C1/C2) were significantly upregulated by TrkA, whereas α-enolase modification was downregulated by TrkA, and it was suppressed by GW441756, indicating that TrkA activity is required for their modifications. Taken together, we suggest here that the major novel TrkA-dependent targets such as α-tubulin, hnRNP C1/C2, and α-enolase could play an essential role in TrkA-mediated tyrosine phosphorylation signaling pathways via regulation of their posttranslational modifications.
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Affiliation(s)
- Eun Joo Jung
- Department of Biochemistry and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, South Korea
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Eyckmans J, Lin GL, Chen CS. Adhesive and mechanical regulation of mesenchymal stem cell differentiation in human bone marrow and periosteum-derived progenitor cells. Biol Open 2012; 1:1058-68. [PMID: 23213385 PMCID: PMC3507189 DOI: 10.1242/bio.20122162] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 06/27/2012] [Indexed: 11/23/2022] Open
Abstract
It has previously been demonstrated that cell shape can influence commitment of human bone marrow-derived mesenchymal stem cells (hBMCs) to adipogenic, osteogenic, chondrogenic, and other lineages. Human periosteum-derived cells (hPDCs) exhibit multipotency similar to hBMCs, but hPDCs may offer enhanced potential for osteogenesis and chondrogenesis given their apparent endogenous role in bone and cartilage repair in vivo. Here, we examined whether hPDC differentiation is regulated by adhesive and mechanical cues comparable to that reported for hBMC differentiation. When cultured in the appropriate induction media, hPDCs at high cell seeding density demonstrated enhanced levels of adipogenic or chondrogenic markers as compared with hPDCs at low cell seeding density. Cell seeding density correlated inversely with projected area of cell spreading, and directly limiting cell spreading with micropatterned substrates promoted adipogenesis or chondrogenesis while substrates promoting cell spreading supported osteogenesis. Interestingly, cell seeding density influenced differentiation through both changes in cell shape and non-shape-mediated effects: density-dependent adipogenesis and chondrogenesis were regulated primarily by cell shape whereas non-shape effects strongly influenced osteogenic potential. Inhibition of cytoskeletal contractility by adding the Rho kinase inhibitor Y27632 further enhanced adipogenic differentiation and discouraged osteogenic differentiation of hPDCs. Together, our results suggest that multipotent lineage decisions of hPDCs are impacted by cell adhesive and mechanical cues, though to different extents than hBMCs. Thus, future studies of hPDCs and other primary stem cell populations with clinical potential should consider varying biophysical metrics for more thorough optimization of stem cell differentiation.
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Affiliation(s)
- Jeroen Eyckmans
- Department of Bioengineering, University of Pennsylvania , 510 Skirkanich Hall, 210 South 33rd Street, Philadelphia, PA 19104 , USA ; Laboratory for Skeletal Development and Joint Disorders, Katholieke Universiteit Leuven , Herestraat 49, Box 813, B-3000 Leuven , Belgium
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Kanlaya R, Pattanakitsakul SN, Sinchaikul S, Chen ST, Thongboonkerd V. Vimentin interacts with heterogeneous nuclear ribonucleoproteins and dengue nonstructural protein 1 and is important for viral replication and release. MOLECULAR BIOSYSTEMS 2010; 6:795-806. [PMID: 20567765 DOI: 10.1039/b923864f] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Our previous study using expression proteomics demonstrated that many proteins, particularly five forms of heterogeneous nuclear ribonucleoproteins (hnRNPs), were up-regulated in human endothelial cells upon dengue virus infection. To address functional significance of these proteins in response to dengue virus infection, we performed a functional proteomics study to identify hnRNPs-interacting proteins in the infected EA.hy926 cells. Immunoprecipitation followed by 2-D PAGE and mass spectrometric analyses revealed 18 and 13 interacting partners of hnRNP C1/C2 and hnRNP K, respectively. Interestingly, vimentin was a common partner for both hnRNP C1/C2 and K. The interaction between vimentin and these hnRNPs was confirmed by reciprocal immunoprecipitation followed by Western blot analysis and also by double immunofluorescence staining. Disruption of vimentin intermediate filament by acrylamide not only dissociated these complexes but also reduced nuclear hnRNPs expression, whereas cytosolic hnRNPs expression was unchanged. We also demonstrated that vimentin was strongly associated with dengue non-structural protein 1 (NS1). Disruption of vimentin intermediate filament not only dissociated this complex but also reduced dengue NS1 expression, as well as viral replication and release. Our data report for the first time that vimentin interacts with hnRNPs and dengue NS1, and plays a crucial role in replication and release of dengue virus.
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Affiliation(s)
- Rattiyaporn Kanlaya
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, 12th Floor Adulyadejvikrom Building, 2 Prannok Road, Bangkoknoi, Bangkok 10700, Thailand
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Son Y, Kim S, Choi K, Park Y, Eo S, Kim Y, Rhim B, Kim K. p35 interacts with α-tubulin and organelle proteins: Nuclear translocation of p35 in dying cells. Proteomics 2009; 9:4036-47. [DOI: 10.1002/pmic.200900122] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Xiao L, Eto M, Kazanietz MG. ROCK mediates phorbol ester-induced apoptosis in prostate cancer cells via p21Cip1 up-regulation and JNK. J Biol Chem 2009; 284:29365-75. [PMID: 19667069 DOI: 10.1074/jbc.m109.007971] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
It is established that androgen-dependent prostate cancer cells undergo apoptosis upon treatment with phorbol esters and related analogs, an effect primarily mediated by PKCdelta. Treatment of LNCaP prostate cancer cells with phorbol 12-myristate 13-acetate (PMA) causes a strong and sustained activation of RhoA and its downstream effector ROCK (Rho kinase) as well as the formation of stress fibers. These effects are impaired in cells subjected to PKCdelta RNA interference depletion. Functional studies revealed that expression of a dominant negative RhoA mutant or treatment with the ROCK inhibitor Y-27632 inhibits the apoptotic effect of PMA in LNCaP cells. Remarkably, the cytoskeleton inhibitors cytochalasin B and blebbistatin blocked not only PMA-induced apoptosis but also the activation of JNK, a mediator of the cell death effect by the phorbol ester. In addition, we found that up-regulation of the cell cycle inhibitor p21(Cip1) is required for PMA-induced apoptosis and that inhibitors of ROCK or the cytoskeleton organization prevent p21(Cip1) induction. Real time PCR analysis and reporter gene assay revealed that PMA induces p21(Cip1) transcriptionally in a ROCK- and cytoskeleton-dependent manner. p21(Cip1) promoter analysis revealed that PMA induction is dependent on Sp1 elements in the p21(Cip1) promoter but independent of p53. Taken together, our studies implicate ROCK-mediated up-regulation of p21(Cip1) and the cytoskeleton in PKCdelta-dependent apoptosis in prostate cancer cells.
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Affiliation(s)
- Liqing Xiao
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6160, USA
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Noisakran S, Sengsai S, Thongboonkerd V, Kanlaya R, Sinchaikul S, Chen ST, Puttikhunt C, Kasinrerk W, Limjindaporn T, Wongwiwat W, Malasit P, Yenchitsomanus PT. Identification of human hnRNP C1/C2 as a dengue virus NS1-interacting protein. Biochem Biophys Res Commun 2008; 372:67-72. [PMID: 18471994 DOI: 10.1016/j.bbrc.2008.04.165] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Accepted: 04/28/2008] [Indexed: 01/24/2023]
Abstract
Dengue virus nonstructural protein 1 (NS1) is a key glycoprotein involved in the production of infectious virus and the pathogenesis of dengue diseases. Very little is known how NS1 interacts with host cellular proteins and functions in dengue virus-infected cells. This study aimed at identifying NS1-interacting host cellular proteins in dengue virus-infected cells by employing co-immunoprecipitation, two-dimensional gel electrophoresis, and mass spectrometry. Using lysates of dengue virus-infected human embryonic kidney cells (HEK 293T), immunoprecipitation with an anti-NS1 monoclonal antibody revealed eight isoforms of dengue virus NS1 and a 40-kDa protein, which was subsequently identified by quadrupole time-of-flight tandem mass spectrometry (Q-TOF MS/MS) as human heterogeneous nuclear ribonucleoprotein (hnRNP) C1/C2. Further investigation by co-immunoprecipitation and co-localization confirmed the association of hnRNP C1/C2 and dengue virus NS1 proteins in dengue virus-infected cells. Their interaction may have implications in virus replication and/or cellular responses favorable to survival of the virus in host cells.
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Affiliation(s)
- Sansanee Noisakran
- Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand
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14
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Christian KJ, Lang MA, Raffalli-Mathieu F. Interaction of heterogeneous nuclear ribonucleoprotein C1/C2 with a novel cis-regulatory element within p53 mRNA as a response to cytostatic drug treatment. Mol Pharmacol 2008; 73:1558-67. [PMID: 18296503 DOI: 10.1124/mol.107.042507] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We describe a novel cis-element in the 5' coding region of p53 mRNA and its interaction with heterogeneous nuclear ribonucleoprotein (hnRNP)C1/C2. This element is located in a putative hairpin loop structure, within the first 101 nucleotides downstream of the start codon. The binding of hnRNPC1/C2 is strongly enhanced in response to the DNA-damaging drug cisplatin [cis-diamminedichloroplatinum(II)] and the cytostatic transcriptional inhibitor actinomycin D (dactinomycin), both known inducers of apoptosis and p53. Strongly stimulated binding is observed in both nuclear and cytoplasmic compartments, and it is accompanied by a cytoplasmic increase of hnRNPC1/C2. Changes in hnRNPC1/C2 protein levels are not proportional to binding activity, suggesting qualitative changes in hnRNPC1/C2 upon activation. Phosphorylation studies reveal contrasting characteristics of the cytoplasmic and nuclear hnRNPC1/C2 interaction with p53 mRNA. Results from chimeric p53-luciferase reporter constructs suggest that hnRNPC1/C2 regulates p53 expression via this binding site. Our results are consistent with a mechanism in which the interaction of hnRNPC1/C2 with a cis-element within the coding region of the p53 transcript regulates the expression of p53 mRNA before and during apoptosis. In addition, we report that preapoptotic signals induced by transcriptional inhibition trigger the appearance of a truncated, exclusively cytoplasmic 43-kDa variant of p53 before apoptosis.
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Affiliation(s)
- Kyle J Christian
- Division of Pharmaceutical Biochemistry, Uppsala Biomedical Center, Box 578 Biomedicum, Uppsala University, S-75123 Uppsala, Sweden.
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15
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Shi J, Wei L. Rho kinase in the regulation of cell death and survival. Arch Immunol Ther Exp (Warsz) 2007; 55:61-75. [PMID: 17347801 PMCID: PMC2612781 DOI: 10.1007/s00005-007-0009-7] [Citation(s) in RCA: 198] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Accepted: 12/21/2006] [Indexed: 12/19/2022]
Abstract
Rho kinase (ROCK) belongs to a family of serine/threonine kinases that are activated via interaction with Rho GTPases. ROCK is involved in a wide range of fundamental cellular functions, such as contraction, adhesion, migration, and proliferation. Recent studies have shown that ROCK plays an important role in the regulation of apoptosis in various cell types and animal disease models. Two ROCK isoforms, ROCK1 and ROCK2, are assumed to be function redundant, this based largely on kinase construct overexpression and chemical inhibitors (Y27632 and fasudil) which inhibit both ROCK1 and ROCK2. Gene targeting and RNA interference approaches allow further dissection of distinct cellular, physiological, and patho-physiological functions of the two ROCK isoforms. This review, based on recent molecular, cellular, and animal studies, focuses on the current understanding of ROCK signaling in the regulation of apoptosis and highlights new findings from recently generated ROCK-deficient mice.
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Affiliation(s)
- Jianjian Shi
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, School of Medicine, R4 building, Room 370, 1044 West Walnut Str, Indianapolis, IN 46202-5225, USA
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16
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Chen H, Hewison M, Adams JS. Functional Characterization of Heterogeneous Nuclear Ribonuclear Protein C1/C2 in Vitamin D Resistance. J Biol Chem 2006; 281:39114-20. [PMID: 17071612 DOI: 10.1074/jbc.m608006200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Clinically apparent hereditary vitamin D-resistant rickets (HVDRR) usually results from a loss of function mutation in the vitamin D receptor (VDR). We recently described a human with the classical HVDRR phenotype but normal VDR function. Hormone resistance resulted from constitutive overexpression of heterogeneous nuclear ribonucleoprotein (hnRNP) that competed with a normally functioning VDR-retinoid X receptor (RXR) dimer for binding to the vitamin D response element (VDRE). Here we describe the purification, molecular cloning, and expression of this vitamin D resistance-causing, competitive response element-binding protein (REBiP) hnRNP C1/C2. When overexpressed in vitamin D-responsive cells, cDNAs for both hnRNPC1 and hnRNPC2 inhibited VDR-VDRE-directed transactivation (28 and 43%, respectively; both p < 0.005). By contrast, transient expression of an hnRNP C1/C2 small interfering RNA increased VDR transactivation by 39% (p < 0.005). Chromatin immunoprecipitation of nucleoproteins bound to the transcriptionally active 1,25-dihydroxy vitamin D-driven CYP24 promoter revealed the presence of REBiP in vitamin D-responsive human cells and indicated that the normal pattern of 1,25-dihydroxy vitamin D-initiated cyclical movement of the VDR on and off the VDRE is legislated by competitive, reciprocal occupancy of the VDRE by hnRNP C1/C2. The temporal and reciprocal pattern of VDR and hnRNPC1/C2 interaction with the VDRE was lost in HVDRR cells overexpressing the hnRNP C1/C2 REBiP. These observations provide further evidence for the functional importance of REBiP as a component of the multiprotein complex involved in the regulation of vitamin D-mediated transcription. In particular, chromatin immunoprecipitation data suggest that, in addition to its RNA-processing functions, hnRNP C1/C2 may be a key determinant of the temporal patterns of VDRE occupancy.
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Affiliation(s)
- Hong Chen
- Division of Endocrinology, Diabetes and Metabolism, Burns and Allen Research Institute, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, California 90048, USA
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17
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Tabbert A, Kappes F, Knippers R, Kellermann J, Lottspeich F, Ferrando-May E. Hypophosphorylation of the architectural chromatin protein DEK in death-receptor-induced apoptosis revealed by the isotope coded protein label proteomic platform. Proteomics 2006; 6:5758-72. [PMID: 17001602 DOI: 10.1002/pmic.200600197] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
During apoptosis nuclear morphology changes dramatically due to alterations of chromatin architecture and cleavage of structural nuclear proteins. To characterize early events in apoptotic nuclear dismantling we have performed a proteomic study of apoptotic nuclei. To this end we have combined a cell-free apoptosis system with a proteomic platform based on the differential isotopic labeling of primary amines with N-nicotinoyloxy-succinimide. We exploited the ability of this system to produce nuclei arrested at different stages of apoptosis to analyze proteome alterations which occur prior to or at a low level of caspase activation. We show that the majority of proteins affected at the onset of apoptosis are involved in chromatin architecture and RNA metabolism. Among them is DEK, an architectural chromatin protein which is linked to autoimmune disorders. The proteomic analysis points to the occurrence of multiple PTMs in early apoptotic nuclei. This is confirmed by showing that the level of phosphorylation of DEK is decreased following apoptosis induction. These results suggest the unexpected existence of an early crosstalk between cytoplasm and nucleus during apoptosis. They further establish a previously unrecognized link between DEK and cell death, which will prove useful in the elucidation of the physiological function of this protein.
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Affiliation(s)
- Anja Tabbert
- University of Konstanz, Molecular Toxicology Group, Konstanz, Germany
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18
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Abstract
Exposure of cells to phorbol ester activates protein kinase C (PKC) to induce apoptosis or differentiation, depending on the cellular context. In erythroblastic cell lines, TF-1 and D2, upregulation of the RhoA signaling promotes phorbol ester-induced apoptosis through activating Rho-associated kinase (ROCK)/phosphorylation of myosin light chain (MLC), thus generating membrane contraction force. As a result, cell adhesion is inhibited and death receptor-mediated death pathway is activated in these cells with a concurrent changes in nucleocytoplasmic signaling for protein trafficking. A microtubule-regulated GEF-H1, which is a specific RhoA activator, was identified to contribute to RhoA activation in these cells. Thus, a cytoskeleton-regulated RhoA signaling cooperates with PKC activation constitutes a cellular context to determine the cell fate in response to phorbol ester stimulation.
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Affiliation(s)
- Zee-Fen Chang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei, Taiwan, ROC.
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19
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Chang YC, Lee HH, Chen YJ, Bokoch GM, Chang ZF. Contribution of guanine exchange factor H1 in phorbol ester-induced apoptosis. Cell Death Differ 2006; 13:2023-32. [PMID: 16601754 DOI: 10.1038/sj.cdd.4401901] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Phorbol-12-myristate-13-acetate (PMA) treatment induces erythroblastoma D2 cells kept in suspension to undergo RhoA-dependent contraction and to become proapoptotic, while attached cells are induced to differentiate accompanied by the reduction of RhoA activity. In this study, we found that guanine exchange factor H1 (GEF-H1) is highly expressed in D2 cells. Depletion of GEF-H1 expression in D2 cells decreased RhoA activity and prevented PMA-induced contraction and apoptosis. Upon PMA stimulation, GEF-H1 became associated with microtubules in cells that were induced to differentiate. As a contrast, in the proapoptotic population of cells GEF-H1 stayed in the cytoplasm without showing PMA-responsive microtubule translocation. Given that GEF-H1 is inactivated when associated with microtubules and its release into cytosol due to depolymerization of microtubules activates RhoA, our results demonstrated that nonmicrotubule-associated GEF-H1 in D2 cells contributes to the sustained activation of RhoA/ROCK signaling in suspension cells, making cells susceptible to PMA-induced apoptosis.
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Affiliation(s)
- Y-C Chang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, No. 1 Section 1 Jen-Ai Road, Taipei, Taiwan, ROC
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20
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Thiede B, Kretschmer A, Rudel T. Quantitative proteome analysis of CD95 (Fas/Apo-1)-induced apoptosis by stable isotope labeling with amino acids in cell culture, 2-DE and MALDI-MS. Proteomics 2006; 6:614-22. [PMID: 16342138 DOI: 10.1002/pmic.200500120] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Proteome analysis of Jurkat T cells induced to undergo apoptosis by CD95 (Fas/Apo-1) treatment was performed to identify modified proteins. We used stable isotope labeling with amino acids in cell culture (SILAC) using leucine to identify proteins of apoptotic and control Jurkat T cells by 2-DE and MALDI-MS. Out of 224 spots analyzed, we quantified 213 spots with 3.5 leucine-containing peptide pairs on average; 28 proteins with a relative abundance of higher than 1.5 were found. Five new modified proteins including calcyclin binding protein, cytosolic acyl coenzyme A thioester hydrolase, heterogeneous ribonucleoprotein M, replication factor C 37-kDa subunit, and tropomyosin 4 chain were identified as being modified in response to apoptosis. In comparison to differential proteome analysis via silver-stained 2-D gels and PMF of total Jurkat T cell lysates, 15 additional apoptosis-modified proteins were identified though 8 proteins were not found. The described approach using SILAC instead of silver staining for relative quantification was simpler to perform regarding the number of required 2-D gels, that cumbersome gel comparisons were avoided, and more apoptosis-modified proteins were identified, but with a higher demand on data interpretation of the mass spectra obtained.
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Affiliation(s)
- Bernd Thiede
- Max Planck Institute for Infection Biology, Department Molecular Biology, Berlin, Germany
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Lewis SM, Holcik M. IRES in distress: translational regulation of the inhibitor of apoptosis proteins XIAP and HIAP2 during cell stress. Cell Death Differ 2005; 12:547-53. [PMID: 15818406 DOI: 10.1038/sj.cdd.4401602] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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22
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Zhao M, Discipio RG, Wimmer AG, Schraufstatter IU. Regulation of CXCR4-Mediated Nuclear Translocation of Extracellular Signal-Related Kinases 1 and 2. Mol Pharmacol 2005; 69:66-75. [PMID: 16210428 DOI: 10.1124/mol.105.016923] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Activation of the chemokine receptor CXCR4 by its agonist stromal cell-derived factor 1 (SDF-1) has been associated with cell migration and proliferation in many cell types, but the intracellular signaling cascades are incompletely defined. Here we show that CXCR4-dependent extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation was mediated through the Ras/Raf pathway, as demonstrated with a dominant-negative Ras mutant and pharmacological inhibitors. The Src inhibitor 4-amino-5-methylphenyl-7-(t-butyl)pyrazolo[3,4-d] pyrimidine (PP1) and the Rho-kinase (ROCK) inhibitor N-(4-pyridyl)-4-(1-aminoethyl)cyclohexanecarboxamide dihydrochloride (Y27632) also attenuated SDF-1-induced ERK1/2 phosphorylation. Involvement of Src could furthermore be demonstrated by Src phosphorylation and by the shortened ERK1/2 phosphorylation in SYF cells, which are Src/Yes/Fyn-deficient compared with Src-reconstituted Src(++) cells. Membrane translocation of RhoA could be detected similarly. A large portion of the SDF-1-mediated ERK phosphorylation was detected in the nucleus, as shown by Western blotting and confocal microscopy, and resulted in the phosphorylation of the transcription factor Elk. It is interesting that the nuclear accumulation of ERK1/2 and Elk phosphorylation was completely blocked by dominant-negative Rho, Y27632, PP1, and latrunculin B, indicating that the Rho/ROCK pathway, Src kinase, and the actin cytoskeleton were required in this process. In accordance, neither nuclear ERK phosphorylation nor Elk phosphorylation were observed in SYF cells stimulated with SDF-1 but were reconstituted in Src(++) cells. In summary, these results demonstrate that Src, Rho/ROCK, and an intact cytoskeleton contribute to overall ERK1/2 activation in SDF-1-stimulated cells and are indispensable for nuclear translocation of ERK1/2 and activation of transcription factors.
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Affiliation(s)
- Ming Zhao
- Division of Cancer Biology, La Jolla Institute for Molecular Medicine, 4570 Executive Drive, Suite 100, San Diego, CA 92121, USA.
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