1
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Ni D, Qi Z, Wang Y, Man Y, Pang J, Tang W, Chen J, Li J, Li G. KLF15-activated MARCH2 boosts cell proliferation and epithelial-mesenchymal transition and presents diagnostic significance for hepatocellular carcinoma. Exp Cell Res 2024; 440:114117. [PMID: 38848952 DOI: 10.1016/j.yexcr.2024.114117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 05/07/2024] [Accepted: 06/03/2024] [Indexed: 06/09/2024]
Abstract
PURPOSE Membrane associated ubiquitin ligase MARCH2 majorly involves in inflammation response and protein trafficking. However, its comprehensive role in hepatocellular carcinoma (HCC) is largely unknown. METHODS Firstly, multiple bioinformatic analyses were applied to determine MARCH2 mRNA level, its expression comparison in diverse molecular and immune subtypes, and diagnostic value in HCC. Subsequently, RNA-seq, real-time quantitative PCR, immunohistochemistry and cell proliferation assay are used to explore the epithelial-mesenchymal transition (EMT) and proliferation by gene-silencing or overexpressing in cultured HCC cells or in vivo xenograft. Moreover, dual luciferase reporter assay and immunoblotting are delved into verify the transcription factor that activating MARCH2 promoter. RESULTS Multiple bioinformatic analyses demonstrate that MARCH2 is upregulated in multiple cancer types and exhibits startling diagnostic value as well as distinct molecular and immune subtypes in HCC. RNA-seq analysis reveals MARCH2 may promote EMT, cell proliferation and migration in HepG2 cells. Furthermore, overexpression of MARCH2 triggers EMT and significantly enhances HCC cell migration, proliferation and colony formation in a ligase activity-dependent manner. Additionally, above observations are validated in the HepG2 mice xenografts. For up-stream mechanism, transcription factor KLF15 is highly expressed in HCC and activates MARCH2 expression. CONCLUSION KLF15 activated MARCH2 triggers EMT and serves as a fascinating biomarker for precise diagnosis of HCC. Consequently, MARCH2 emerges as a promising candidate for target therapy in cancer management.
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Affiliation(s)
- Dongsheng Ni
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China; Graduate School of Peking Union Medical College, Beijing, 100730, PR China
| | - Zhaolai Qi
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China; Graduate School of Peking Union Medical College, Beijing, 100730, PR China
| | - Yuefeng Wang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China
| | - Yong Man
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China
| | - Jing Pang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China
| | - Weiqing Tang
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China
| | - Jingzhou Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China; National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Fuwai Central-China Hospital, Central-China Branch of National Center for Cardiovascular Diseases, Zhengzhou, PR China
| | - Jian Li
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China
| | - Guoping Li
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730, PR China; Graduate School of Peking Union Medical College, Beijing, 100730, PR China.
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2
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Saferali A, Kim W, Xu Z, Chase RP, Cho MH, Laederach A, Castaldi PJ, Hersh CP. Colocalization analysis of 3' UTR alternative polyadenylation quantitative trait loci reveals novel mechanisms underlying associations with lung function. Hum Mol Genet 2024; 33:1164-1175. [PMID: 38569558 DOI: 10.1093/hmg/ddae055] [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: 09/18/2023] [Revised: 02/02/2024] [Indexed: 04/05/2024] Open
Abstract
While many disease-associated single nucleotide polymorphisms (SNPs) are expression quantitative trait loci (eQTLs), a large proportion of genome-wide association study (GWAS) variants are of unknown function. Alternative polyadenylation (APA) plays an important role in posttranscriptional regulation by allowing genes to shorten or extend 3' untranslated regions (UTRs). We hypothesized that genetic variants that affect APA in lung tissue may lend insight into the function of respiratory associated GWAS loci. We generated alternative polyadenylation (apa) QTLs using RNA sequencing and whole genome sequencing on 1241 subjects from the Lung Tissue Research Consortium (LTRC) as part of the NHLBI TOPMed project. We identified 56 179 APA sites corresponding to 13 582 unique genes after filtering out APA sites with low usage. We found that a total of 8831 APA sites were associated with at least one SNP with q-value < 0.05. The genomic distribution of lead APA SNPs indicated that the majority are intronic variants (33%), followed by downstream gene variants (26%), 3' UTR variants (17%), and upstream gene variants (within 1 kb region upstream of transcriptional start site, 10%). APA sites in 193 genes colocalized with GWAS data for at least one phenotype. Genes containing the top APA sites associated with GWAS variants include membrane associated ring-CH-type finger 2 (MARCHF2), nectin cell adhesion molecule 2 (NECTIN2), and butyrophilin subfamily 3 member A2 (BTN3A2). Overall, these findings suggest that APA may be an important mechanism for genetic variants in lung function and chronic obstructive pulmonary disease (COPD).
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Affiliation(s)
- Aabida Saferali
- Channing Division of Network Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, United States
| | - Wonji Kim
- Channing Division of Network Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, United States
| | - Zhonghui Xu
- Channing Division of Network Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, United States
| | - Robert P Chase
- Channing Division of Network Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, United States
| | - Michael H Cho
- Channing Division of Network Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, United States
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115, United States
| | - Alain Laederach
- Department of Biology, University of North Carolina at Chapel Hill, 120 South Road, Chapel Hill, NC 27599, United States
| | - Peter J Castaldi
- Channing Division of Network Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, United States
- Division of General Medicine and Primary Care, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, United States
| | - Craig P Hersh
- Channing Division of Network Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, United States
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115, United States
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3
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Okiyoneda T, Borgo C, Bosello Travain V, Pedemonte N, Salvi M. Targeting ubiquitination machinery in cystic fibrosis: Where do we stand? Cell Mol Life Sci 2024; 81:271. [PMID: 38888668 DOI: 10.1007/s00018-024-05295-z] [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: 03/27/2024] [Revised: 05/16/2024] [Accepted: 05/25/2024] [Indexed: 06/20/2024]
Abstract
Cystic Fibrosis (CF) is a genetic disease caused by mutations in CFTR gene expressing the anion selective channel CFTR located at the plasma membrane of different epithelial cells. The most commonly investigated variant causing CF is F508del. This mutation leads to structural defects in the CFTR protein, which are recognized by the endoplasmic reticulum (ER) quality control system. As a result, the protein is retained in the ER and degraded via the ubiquitin-proteasome pathway. Although blocking ubiquitination to stabilize the CFTR protein has long been considered a potential pharmacological approach in CF, progress in this area has been relatively slow. Currently, no compounds targeting this pathway have entered clinical trials for CF. On the other hand, the emergence of Orkambi initially, and notably the subsequent introduction of Trikafta/Kaftrio, have demonstrated the effectiveness of molecular chaperone-based therapies for patients carrying the F508del variant and even showed efficacy against other variants. These treatments directly target the CFTR variant protein without interfering with cell signaling pathways. This review discusses the limits and potential future of targeting protein ubiquitination in CF.
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Affiliation(s)
- Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo, 669-1330, Japan.
| | - Christian Borgo
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy
- Department of Medicine, University of Padova, 35128, Padova, Italy
| | | | - Nicoletta Pedemonte
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genoa, Italy
| | - Mauro Salvi
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy.
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4
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Ito K, Harada I, Martinez C, Sato K, Lee E, Port E, Byerly JH, Nayak A, Tripathi E, Zhu J, Irie HY. MARCH2, a Novel Oncogene-regulated SNAIL E3 Ligase, Suppresses Triple-negative Breast Cancer Metastases. CANCER RESEARCH COMMUNICATIONS 2024; 4:946-957. [PMID: 38457262 PMCID: PMC10977041 DOI: 10.1158/2767-9764.crc-23-0090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 01/02/2024] [Accepted: 03/04/2024] [Indexed: 03/10/2024]
Abstract
Epithelial-mesenchymal transition (EMT) in cancer promotes metastasis and chemotherapy resistance. A subset of triple-negative breast cancer (TNBC) exhibits a mesenchymal gene signature that is associated with poor patient outcomes. We previously identified PTK6 tyrosine kinase as an oncogenic driver of EMT in a subset of TNBC. PTK6 induces EMT by stabilizing SNAIL, a key EMT-initiating transcriptional factor. Inhibition of PTK6 activity reverses mesenchymal features of TNBC cells and suppresses their metastases by promoting SNAIL degradation via a novel mechanism. In the current study, we identify membrane-associated RING-CH2 (MARCH2) as a novel PTK6-regulated E3 ligase that promotes the ubiquitination and degradation of SNAIL protein. The MARCH2 RING domain is critical for SNAIL ubiquitination and subsequent degradation. PTK6 inhibition promotes the interaction of MARCH2 with SNAIL. Overexpression of MARCH2 exhibits tumor suppressive properties and phenocopies the effects of SNAIL downregulation and PTK6 inhibition in TNBC cells, such as inhibition of migration, anoikis resistance, and metastasis. Consistent with this, higher levels of MARCH2 expression in breast and other cancers are associated with better prognosis. We have identified MARCH2 as a novel SNAIL E3 ligase that regulates EMT and metastases of mesenchymal TNBC. SIGNIFICANCE EMT is a process directly linked to drug resistance and metastasis of cancer cells. We identified MARCH2 as a novel regulator of SNAIL, a key EMT driver, that promotes SNAIL ubiquitination and degradation in TNBC cells. MARCH2 is oncogene regulated and inhibits growth and metastasis of TNBC. These insights could contribute to novel strategies to therapeutically target TNBC.
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Affiliation(s)
- Koichi Ito
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Ibuki Harada
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Criseyda Martinez
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Katsutoshi Sato
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | | | - Elisa Port
- Department of Surgery, Mount Sinai Hospital, New York, New York
| | - Jessica H Byerly
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Anupma Nayak
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ekta Tripathi
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jun Zhu
- Sema4, Stamford, Connecticut
| | - Hanna Y Irie
- Division of Hematology and Medical Oncology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
- Department of Oncological Sciences, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York
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5
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Kok M, Hartnett-Scott K, Happe CL, MacDonald ML, Aizenman E, Brodsky JL. The expression system influences stability, maturation efficiency, and oligomeric properties of the potassium-chloride co-transporter KCC2. Neurochem Int 2024; 174:105695. [PMID: 38373478 PMCID: PMC10923169 DOI: 10.1016/j.neuint.2024.105695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/21/2024]
Abstract
The neuron-specific K+/Cl- co-transporter 2, KCC2, which is critical for brain development, regulates γ-aminobutyric acid-dependent inhibitory neurotransmission. Consistent with its function, mutations in KCC2 are linked to neurodevelopmental disorders, including epilepsy, schizophrenia, and autism. KCC2 possesses 12 transmembrane spans and forms an intertwined dimer. Based on its complex architecture and function, reduced cell surface expression and/or activity have been reported when select disease-associated mutations are present in the gene encoding the protein, SLC12A5. These data suggest that KCC2 might be inherently unstable, as seen for other complex polytopic ion channels, thus making it susceptible to cellular quality control pathways that degrade misfolded proteins. To test these hypotheses, we examined KCC2 stability and/or maturation in five model systems: yeast, HEK293 cells, primary rat neurons, and rat and human brain synaptosomes. Although studies in yeast revealed that KCC2 is selected for endoplasmic reticulum-associated degradation (ERAD), experiments in HEK293 cells supported a more subtle role for ERAD in maintaining steady-state levels of KCC2. Nevertheless, this system allowed for an analysis of KCC2 glycosylation in the ER and Golgi, which serves as a read-out for transport through the secretory pathway. In turn, KCC2 was remarkably stable in primary rat neurons, suggesting that KCC2 folds efficiently in more native systems. Consistent with these data, the mature glycosylated form of KCC2 was abundant in primary rat neurons as well as in rat and human brain. Together, this work details the first insights into the influence that the cellular and membrane environments have on several fundamental KCC2 properties, acknowledges the advantages and disadvantages of each system, and helps set the stage for future experiments to assess KCC2 in a normal or disease setting.
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Affiliation(s)
- Morgan Kok
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Karen Hartnett-Scott
- Department of Neurobiology and the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Cassandra L Happe
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Matthew L MacDonald
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Elias Aizenman
- Department of Neurobiology and the Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
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6
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Umthong S, Timilsina U, D’Angelo M, Stavrou S. Determining the antiviral mechanism of MARCH2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.18.558306. [PMID: 37786722 PMCID: PMC10541590 DOI: 10.1101/2023.09.18.558306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Membrane-associated RING-CH (MARCH) 2 protein is a member of the MARCH protein family of RING-CH finger E3 ubiquitin ligases that have important functions in regulating the levels of proteins found on the cell surface. MARCH1, 2 and 8 inhibit HIV-1 infection by preventing the incorporation of the envelope glycoproteins in nascent virions. However, a better understanding on the mechanism utilized by MARCH proteins to restrict HIV-1 is needed. In this report, we identify an amino acid in human MARCH2, that is absent in mouse MARCH2, critical for its antiretroviral function. Moreover, we map the domains of human MARCH2 critical for restricting as well as binding to the HIV-1 envelope glycoproteins. Our findings reveal important new aspects of the antiviral mechanism utilized by human MARCH2 to restrict HIV-1 that have potential implications to all MARCH proteins with antiviral functions.
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Affiliation(s)
- Supawadee Umthong
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
- Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Uddhav Timilsina
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
| | - Mary D’Angelo
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
| | - Spyridon Stavrou
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, United States
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7
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Popov G, Fiebig-Comyn A, Syriste L, Little DJ, Skarina T, Stogios PJ, Birstonas S, Coombes BK, Savchenko A. Distinct Molecular Features of NleG Type 3 Secreted Effectors Allow for Different Roles during Citrobacter rodentium Infection in Mice. Infect Immun 2023; 91:e0050522. [PMID: 36511702 PMCID: PMC9872709 DOI: 10.1128/iai.00505-22] [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: 11/17/2022] [Accepted: 11/19/2022] [Indexed: 12/15/2022] Open
Abstract
The NleGs are the largest family of type 3 secreted effectors in attaching and effacing (A/E) pathogens, such as enterohemorrhagic Escherichia coli (EHEC), enteropathogenic E. coli, and Citrobacter rodentium. NleG effectors contain a conserved C-terminal U-box domain acting as a ubiquitin protein ligase and target host proteins via a variable N-terminal portion. The specific roles of these effectors during infection remain uncertain. Here, we demonstrate that the three NleG effectors-NleG1Cr, NleG7Cr, and NleG8Cr-encoded by C. rodentium DBS100 play distinct roles during infection in mice. Using individual nleGCr knockout strains, we show that NleG7Cr contributes to bacterial survival during enteric infection while NleG1Cr promotes the expression of diarrheal symptoms and NleG8Cr contributes to accelerated lethality in susceptible mice. Furthermore, the NleG8Cr effector contains a C-terminal PDZ domain binding motif that enables interaction with the host protein GOPC. Both the PDZ domain binding motif and the ability to engage with host ubiquitination machinery via the intact U-box domain proved to be necessary for NleG8Cr function, contributing to the observed phenotype during infection. We also establish that the PTZ binding motif in the EHEC NleG8 (NleG8Ec) effector, which shares 60% identity with NleG8Cr, is engaged in interactions with human GOPC. The crystal structure of the NleG8Ec C-terminal peptide in complex with the GOPC PDZ domain, determined to 1.85 Å, revealed a conserved interaction mode similar to that observed between GOPC and eukaryotic PDZ domain binding motifs. Despite these common features, nleG8Ec does not complement the ΔnleG8Cr phenotype during infection, revealing functional diversification between these NleG effectors.
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Affiliation(s)
- Georgy Popov
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Aline Fiebig-Comyn
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Lukas Syriste
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Dustin J. Little
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada
| | - Tatiana Skarina
- Department of Chemical Engineering and Applied Chemistry, Toronto University, Toronto, Ontario, Canada
| | - Peter J. Stogios
- Department of Chemical Engineering and Applied Chemistry, Toronto University, Toronto, Ontario, Canada
| | - Sarah Birstonas
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada
| | - Brian K. Coombes
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Alexei Savchenko
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- Department of Chemical Engineering and Applied Chemistry, Toronto University, Toronto, Ontario, Canada
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8
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Excoffon KJDA, Avila CL, Alghamri MS, Kolawole AO. The magic of MAGI-1: A scaffolding protein with multi signalosomes and functional plasticity. Biol Cell 2022; 114:185-198. [PMID: 35389514 DOI: 10.1111/boc.202200014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/01/2022] [Accepted: 04/04/2022] [Indexed: 11/29/2022]
Abstract
MAGI-1 is a critical cellular scaffolding protein with over 110 different cellular and microbial protein interactors. Since the discovery of MAGI-1 in 1997, MAGI-1 has been implicated in diverse cellular functions such as polarity, cell-cell communication, neurological processes, kidney function, and a host of diseases including cancer and microbial infection. Additionally, MAGI-1 has undergone nomenclature changes in response to the discovery of an additional PDZ domain, leading to lack of continuity in the literature. We address the nomenclature of MAGI-1 as well as summarize many of the critical functions of the known interactions. Given the importance of many of the interactors, such as human papillomavirus E6, the Coxsackievirus and adenovirus receptor (CAR), and PTEN, the enhancement or disruption of MAGI-based interactions has the potential to affect cellular functions that can potentially be harnessed as a therapeutic strategy for a variety of diseases.
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Affiliation(s)
| | - Christina L Avila
- Department of Biological Sciences, Wright State University, Dayton, Ohio, USA
| | - Mahmoud S Alghamri
- Department of Biological Sciences, Wright State University, Dayton, Ohio, USA
| | - Abimbola O Kolawole
- Department of Biological Sciences, Wright State University, Dayton, Ohio, USA
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9
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Borgo C, D'Amore C, Capurro V, Tomati V, Sondo E, Cresta F, Castellani C, Pedemonte N, Salvi M. Targeting the E1 ubiquitin-activating enzyme (UBA1) improves elexacaftor/tezacaftor/ivacaftor efficacy towards F508del and rare misfolded CFTR mutants. Cell Mol Life Sci 2022; 79:192. [PMID: 35292885 PMCID: PMC8924136 DOI: 10.1007/s00018-022-04215-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/16/2022] [Accepted: 02/21/2022] [Indexed: 02/08/2023]
Abstract
The advent of Trikafta (Kaftrio in Europe) (a triple-combination therapy based on two correctors—elexacaftor/tezacaftor—and the potentiator ivacaftor) has represented a revolution for the treatment of patients with cystic fibrosis (CF) carrying the most common misfolding mutation, F508del-CFTR. This therapy has proved to be of great efficacy in people homozygous for F508del-CFTR and is also useful in individuals with a single F508del allele. Nevertheless, the efficacy of this therapy needs to be improved, especially in light of the extent of its use in patients with rare class II CFTR mutations. Using CFBE41o- cells expressing F508del-CFTR, we provide mechanistic evidence that targeting the E1 ubiquitin-activating enzyme (UBA1) by TAK-243, a small molecule in clinical trials for other diseases, boosts the rescue of F508del-CFTR induced by CFTR correctors. Moreover, TAK-243 significantly increases the F508del-CFTR short-circuit current induced by elexacaftor/tezacaftor/ivacaftor in differentiated human primary airway epithelial cells, a gold standard for the pre-clinical evaluation of patients’ responsiveness to pharmacological treatments. This new combinatory approach also leads to an improvement in CFTR conductance on cells expressing other rare CF-causing mutations, including N1303K, for which Trikafta is not approved. These findings show that Trikafta therapy can be improved by the addition of a drug targeting the misfolding detection machinery at the beginning of the ubiquitination cascade and may pave the way for an extension of Trikafta to low/non-responding rare misfolded CFTR mutants.
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Affiliation(s)
- Christian Borgo
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.
| | - Claudio D'Amore
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy
| | - Valeria Capurro
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy
| | - Elvira Sondo
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy
| | - Federico Cresta
- Centro Fibrosi Cistica, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Carlo Castellani
- Centro Fibrosi Cistica, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Nicoletta Pedemonte
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy.
| | - Mauro Salvi
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.
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10
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Farinha CM, Gentzsch M. Revisiting CFTR Interactions: Old Partners and New Players. Int J Mol Sci 2021; 22:13196. [PMID: 34947992 PMCID: PMC8703571 DOI: 10.3390/ijms222413196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 01/07/2023] Open
Abstract
Remarkable progress in CFTR research has led to the therapeutic development of modulators that rescue the basic defect in cystic fibrosis. There is continuous interest in studying CFTR molecular disease mechanisms as not all cystic fibrosis patients have a therapeutic option available. Addressing the basis of the problem by comprehensively understanding the critical molecular associations of CFTR interactions remains key. With the availability of CFTR modulators, there is interest in comprehending which interactions are critical to rescue CFTR and which are altered by modulators or CFTR mutations. Here, the current knowledge on interactions that govern CFTR folding, processing, and stability is summarized. Furthermore, we describe protein complexes and signal pathways that modulate the CFTR function. Primary epithelial cells display a spatial control of the CFTR interactions and have become a common system for preclinical and personalized medicine studies. Strikingly, the novel roles of CFTR in development and differentiation have been recently uncovered and it has been revealed that specific CFTR gene interactions also play an important role in transcriptional regulation. For a comprehensive understanding of the molecular environment of CFTR, it is important to consider CFTR mutation-dependent interactions as well as factors affecting the CFTR interactome on the cell type, tissue-specific, and transcriptional levels.
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Affiliation(s)
- Carlos M. Farinha
- BioISI—Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
| | - Martina Gentzsch
- Marsico Lung Institute and Cystic Fibrosis Research Center, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Pediatrics, Division of Pediatric Pulmonology, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
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11
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Strub MD, Gao L, Tan K, McCray PB. Analysis of multiple gene co-expression networks to discover interactions favoring CFTR biogenesis and ΔF508-CFTR rescue. BMC Med Genomics 2021; 14:258. [PMID: 34717611 PMCID: PMC8557508 DOI: 10.1186/s12920-021-01106-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 10/20/2021] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND We previously reported that expression of a miR-138 mimic or knockdown of SIN3A in primary cultures of cystic fibrosis (CF) airway epithelia increased ΔF508-CFTR mRNA and protein levels, and partially restored CFTR-dependent chloride transport. Global mRNA transcript profiling in ΔF508-CFBE cells treated with miR-138 mimic or SIN3A siRNA identified two genes, SYVN1 and NEDD8, whose inhibition significantly increased ΔF508-CFTR trafficking, maturation, and function. Little is known regarding the dynamic changes in the CFTR gene network during such rescue events. We hypothesized that analysis of condition-specific gene networks from transcriptomic data characterizing ΔF508-CFTR rescue could help identify dynamic gene modules associated with CFTR biogenesis. METHODS We applied a computational method, termed M-module, to analyze multiple gene networks, each of which exhibited differential activity compared to a baseline condition. In doing so, we identified both unique and shared gene pathways across multiple differential networks. To construct differential networks, gene expression data from CFBE cells were divided into three groups: (1) siRNA inhibition of NEDD8 and SYVN1; (2) miR-138 mimic and SIN3A siRNA; and (3) temperature (27 °C for 24 h, 40 °C for 24 h, and 27 °C for 24 h followed by 40 °C for 24 h). RESULTS Interrogation of individual networks (e.g., NEDD8/SYVN1 network), combinations of two networks (e.g., NEDD8/SYVN1 + temperature networks), and all three networks yielded sets of 1-modules, 2-modules, and 3-modules, respectively. Gene ontology analysis revealed significant enrichment of dynamic modules in pathways including translation, protein metabolic/catabolic processes, protein complex assembly, and endocytosis. Candidate CFTR effectors identified in the analysis included CHURC1, GZF1, and RPL15, and siRNA-mediated knockdown of these genes partially restored CFTR-dependent transepithelial chloride current to ΔF508-CFBE cells. CONCLUSIONS The ability of the M-module to identify dynamic modules involved in ΔF508 rescue provides a novel approach for studying CFTR biogenesis and identifying candidate suppressors of ΔF508.
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Affiliation(s)
- Matthew D Strub
- Department of Pediatrics, University of Iowa, 6320 PBDB, 169 Newton Road, Iowa City, IA, 52242, USA.,Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA, 52245, USA
| | - Long Gao
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Kai Tan
- Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.,Department of Pediatrics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Paul B McCray
- Department of Pediatrics, University of Iowa, 6320 PBDB, 169 Newton Road, Iowa City, IA, 52242, USA. .,Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA, 52245, USA.
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12
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Liu X, Xu F, Ren L, Zhao F, Huang Y, Wei L, Wang Y, Wang C, Fan Z, Mei S, Song J, Zhao Z, Cen S, Liang C, Wang J, Guo F. MARCH8 inhibits influenza A virus infection by targeting viral M2 protein for ubiquitination-dependent degradation in lysosomes. Nat Commun 2021; 12:4427. [PMID: 34285233 PMCID: PMC8292393 DOI: 10.1038/s41467-021-24724-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 06/30/2021] [Indexed: 01/05/2023] Open
Abstract
The membrane-associated RING-CH (MARCH) proteins are E3 ligases that regulate the stability of various cellular membrane proteins. MARCH8 has been reported to inhibit the infection of HIV-1 and a few other viruses, thus plays an important role in host antiviral defense. However, the antiviral spectrum and the underlying mechanisms of MARCH8 are incompletely defined. Here, we demonstrate that MARCH8 profoundly inhibits influenza A virus (IAV) replication both in vitro and in mice. Mechanistically, MARCH8 suppresses IAV release through redirecting viral M2 protein from the plasma membrane to lysosomes for degradation. Specifically, MARCH8 catalyzes the K63-linked polyubiquitination of M2 at lysine residue 78 (K78). A recombinant A/Puerto Rico/8/34 virus carrying the K78R M2 protein shows greater replication and more severe pathogenicity in cells and mice. More importantly, we found that the M2 protein of the H1N1 IAV has evolved to acquire non-lysine amino acids at positions 78/79 to resist MARCH8-mediated ubiquitination and degradation. Together, our data support the important role of MARCH8 in host anti-IAV intrinsic immune defense by targeting M2, and suggest the inhibitory pressure of MARCH8 on H1N1 IAV transmission in the human population.
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Affiliation(s)
- Xiaoman Liu
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Fengwen Xu
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Lili Ren
- NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Key Laboratory of Respiratory Disease Pathogenomics, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Fei Zhao
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yu Huang
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Liang Wei
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yingying Wang
- NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Key Laboratory of Respiratory Disease Pathogenomics, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Conghui Wang
- NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.,Key Laboratory of Respiratory Disease Pathogenomics, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Zhangling Fan
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Shan Mei
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jingdong Song
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Zhendong Zhao
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Shan Cen
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Chen Liang
- McGill University AIDS Centre, Lady Davis Institute, Jewish General Hospital, Montreal, Canada
| | - Jianwei Wang
- NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China. .,Key Laboratory of Respiratory Disease Pathogenomics, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
| | - Fei Guo
- NHC Key Laboratory of Systems Biology of Pathogens and Center for AIDS Research, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
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13
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MAGI-1 PDZ2 Domain Blockade Averts Adenovirus Infection via Enhanced Proteolysis of the Apical Coxsackievirus and Adenovirus Receptor. J Virol 2021; 95:e0004621. [PMID: 33762416 DOI: 10.1128/jvi.00046-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Adenoviruses (AdVs) are etiological agents of gastrointestinal, heart, eye, and respiratory tract infections that can be lethal for immunosuppressed people. Many AdVs use the coxsackievirus and adenovirus receptor (CAR) as a primary receptor. The CAR isoform resulting from alternative splicing that includes the eighth exon, CAREx8, localizes to the apical surface of polarized epithelial cells and is responsible for the initiation of AdV infection. We have shown that the membrane level of CAREx8 is tightly regulated by two MAGI-1 PDZ domains, PDZ2 and PDZ4, resulting in increased or decreased AdV transduction, respectively. We hypothesized that targeting the interactions between the MAGI-1 PDZ2 domain and CAREx8 would decrease the apical CAREx8 expression level and prevent AdV infection. Decoy peptides that target MAGI-1 PDZ2 were synthesized (TAT-E6 and TAT-NET1). PDZ2 binding peptides decreased CAREx8 expression and reduced AdV transduction. CAREx8 degradation was triggered by the activation of the regulated intramembrane proteolysis (RIP) pathway through a disintegrin and metalloproteinase (ADAM17) and γ-secretase. Further analysis revealed that ADAM17 interacts directly with the MAGI-1 PDZ3 domain, and blocking the PDZ2 domain enhanced the accessibility of ADAM17 to the substrate (CAREx8). Finally, we validated the efficacy of TAT-PDZ2 peptides in protecting the epithelia from AdV transduction in vivo using a novel transgenic animal model. Our data suggest that TAT-PDZ2 binding peptides are novel anti-AdV molecules that act by enhanced RIP of CAREx8 and decreased AdV entry. This strategy has additional translational potential for targeting other viral receptors that have PDZ binding domains, such as the angiotensin-converting enzyme 2 receptor. IMPORTANCE Adenovirus is a common threat in immunosuppressed populations and military recruits. There are no currently approved treatments/prophylactic agents that protect from most AdV infections. Here, we developed peptide-based small molecules that can suppress AdV infection of polarized epithelia by targeting the AdV receptor, coxsackievirus and adenovirus receptor (CAREx8). The newly discovered peptides target a specific PDZ domain of the CAREx8-interacting protein MAGI-1 and decrease AdV transduction in multiple polarized epithelial models. Peptide-induced CAREx8 degradation is triggered by extracellular domain (ECD) shedding through ADAM17 followed by γ-secretase-mediated nuclear translocation of the C-terminal domain. The enhanced shedding of the CAREx8 ECD further protected the epithelium from AdV infection. Taken together, these novel molecules protect the epithelium from AdV infection. This approach may be applicable to the development of novel antiviral molecules against other viruses that use a receptor with a PDZ binding domain.
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14
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Chathuranga K, Kim TH, Lee H, Park JS, Kim JH, Chathuranga WAG, Ekanayaka P, Choi YJ, Lee CH, Kim CJ, Jung JU, Lee JS. Negative regulation of NEMO signaling by the ubiquitin E3 ligase MARCH2. EMBO J 2020; 39:e105139. [PMID: 32935379 PMCID: PMC7604578 DOI: 10.15252/embj.2020105139] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 08/07/2020] [Accepted: 08/11/2020] [Indexed: 01/01/2023] Open
Abstract
NF‐κB essential modulator (NEMO) is a key regulatory protein that functions during NF‐κB‐ and interferon‐mediated signaling in response to extracellular stimuli and pathogen infections. Tight regulation of NEMO is essential for host innate immune responses and for maintenance of homeostasis. Here, we report that the E3 ligase MARCH2 is a novel negative regulator of NEMO‐mediated signaling upon bacterial or viral infection. MARCH2 interacted directly with NEMO during the late phase of infection and catalyzed K‐48‐linked ubiquitination of Lys326 on NEMO, which resulted in its degradation. Deletion of MARCH2 resulted in marked resistance to bacterial/viral infection, along with increased innate immune responses both in vitro and in vivo. In addition, MARCH2−/− mice were more susceptible to LPS challenge due to massive production of cytokines. Taken together, these findings provide new insight into the molecular regulation of NEMO and suggest an important role for MARCH2 in homeostatic control of innate immune responses.
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Affiliation(s)
| | - Tae-Hwan Kim
- College of Veterinary Medicine, Chungnam National University, Daejeon, Korea.,Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea
| | - Hyuncheol Lee
- College of Veterinary Medicine, Chungnam National University, Daejeon, Korea.,California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
| | - Jun-Seol Park
- College of Veterinary Medicine, Chungnam National University, Daejeon, Korea
| | - Jae-Hoon Kim
- Laboratory Animal Resource Center, Korea Research Institute of Bioscience and Biotechnology, University of Science and Technology (UST), Daejeon, Korea
| | | | - Pathum Ekanayaka
- College of Veterinary Medicine, Chungnam National University, Daejeon, Korea
| | - Youn Jung Choi
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Chul-Ho Lee
- Laboratory Animal Resource Center, Korea Research Institute of Bioscience and Biotechnology, University of Science and Technology (UST), Daejeon, Korea
| | - Chul-Joong Kim
- College of Veterinary Medicine, Chungnam National University, Daejeon, Korea
| | - Jae U Jung
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Jong-Soo Lee
- College of Veterinary Medicine, Chungnam National University, Daejeon, Korea
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15
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Strub MD, McCray, Jr. PB. Transcriptomic and Proteostasis Networks of CFTR and the Development of Small Molecule Modulators for the Treatment of Cystic Fibrosis Lung Disease. Genes (Basel) 2020; 11:genes11050546. [PMID: 32414011 PMCID: PMC7288469 DOI: 10.3390/genes11050546] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/18/2022] Open
Abstract
Cystic fibrosis (CF) is a lethal autosomal recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The diversity of mutations and the multiple ways by which the protein is affected present challenges for therapeutic development. The observation that the Phe508del-CFTR mutant protein is temperature sensitive provided proof of principle that mutant CFTR could escape proteosomal degradation and retain partial function. Several specific protein interactors and quality control checkpoints encountered by CFTR during its proteostasis have been investigated for therapeutic purposes, but remain incompletely understood. Furthermore, pharmacological manipulation of many CFTR interactors has not been thoroughly investigated for the rescue of Phe508del-CFTR. However, high-throughput screening technologies helped identify several small molecule modulators that rescue CFTR from proteosomal degradation and restore partial function to the protein. Here, we discuss the current state of CFTR transcriptomic and biogenesis research and small molecule therapy development. We also review recent progress in CFTR proteostasis modulators and discuss how such treatments could complement current FDA-approved small molecules.
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Affiliation(s)
- Matthew D. Strub
- Interdisciplinary Graduate Program in Genetics, The University of Iowa, Iowa City, IA 52242, USA;
- Stead Family Department of Pediatrics, The University of Iowa, Iowa City, IA 52242, USA
| | - Paul B. McCray, Jr.
- Interdisciplinary Graduate Program in Genetics, The University of Iowa, Iowa City, IA 52242, USA;
- Stead Family Department of Pediatrics, The University of Iowa, Iowa City, IA 52242, USA
- Correspondence: ; Tel.: +1-(319)-335-6844
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16
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Fukuda R, Okiyoneda T. Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Ubiquitylation as a Novel Pharmaceutical Target for Cystic Fibrosis. Pharmaceuticals (Basel) 2020; 13:ph13040075. [PMID: 32331485 PMCID: PMC7243099 DOI: 10.3390/ph13040075] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/20/2020] [Accepted: 04/20/2020] [Indexed: 12/22/2022] Open
Abstract
Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene decrease the structural stability and function of the CFTR protein, resulting in cystic fibrosis. Recently, the effect of CFTR-targeting combination therapy has dramatically increased, and it is expected that add-on drugs that modulate the CFTR surrounding environment will further enhance their effectiveness. Various interacting proteins have been implicated in the structural stability of CFTR and, among them, molecules involved in CFTR ubiquitylation are promising therapeutic targets as regulators of CFTR degradation. This review focuses on the ubiquitylation mechanism that contributes to the stability of mutant CFTR at the endoplasmic reticulum (ER) and post-ER compartments and discusses the possibility as a pharmacological target for cystic fibrosis (CF).
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17
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Regulation of CFTR Biogenesis by the Proteostatic Network and Pharmacological Modulators. Int J Mol Sci 2020; 21:ijms21020452. [PMID: 31936842 PMCID: PMC7013518 DOI: 10.3390/ijms21020452] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/06/2020] [Accepted: 01/08/2020] [Indexed: 12/14/2022] Open
Abstract
Cystic fibrosis (CF) is the most common lethal inherited disease among Caucasians in North America and a significant portion of Europe. The disease arises from one of many mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator, or CFTR. The most common disease-associated allele, F508del, along with several other mutations affect the folding, transport, and stability of CFTR as it transits from the endoplasmic reticulum (ER) to the plasma membrane, where it functions primarily as a chloride channel. Early data demonstrated that F508del CFTR is selected for ER associated degradation (ERAD), a pathway in which misfolded proteins are recognized by ER-associated molecular chaperones, ubiquitinated, and delivered to the proteasome for degradation. Later studies showed that F508del CFTR that is rescued from ERAD and folds can alternatively be selected for enhanced endocytosis and lysosomal degradation. A number of other disease-causing mutations in CFTR also undergo these events. Fortunately, pharmacological modulators of CFTR biogenesis can repair CFTR, permitting its folding, escape from ERAD, and function at the cell surface. In this article, we review the many cellular checkpoints that monitor CFTR biogenesis, discuss the emergence of effective treatments for CF, and highlight future areas of research on the proteostatic control of CFTR.
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18
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Kumar P, Sen C, Peters K, Frizzell RA, Biswas R. Comparative analyses of long non-coding RNA profiles in vivo in cystic fibrosis lung airway and parenchyma tissues. Respir Res 2019; 20:284. [PMID: 31842871 PMCID: PMC6916039 DOI: 10.1186/s12931-019-1259-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 12/09/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Recent advances in the functional analyses of endogenous non-coding RNA (ncRNA) molecules, including long non-coding RNAs (LncRNAs), have provided a new perspective on the crucial roles of RNA in gene regulation. Consequently, LncRNA deregulation is a key factor in various diseases, including pulmonary disorders like Cystic Fibrosis (CF). CF is the most common life limiting recessive disease in the U.S., and is due to mutations in the CFTR gene. CF mutations, of which the most common is F508del-CFTR, prevents correct folding, trafficking and function of the mutant CFTR protein and is further manifested by the hyper-expression of pro-inflammatory cytokines and chemokines into the airway lumen leading to bronchiectasis and culminating in lung destruction. METHODS Here we report a distinct LncRNA signature and corresponding mRNAs that distinguishes CF lung (airway and parenchyma) tissues from matched non-CF controls (n = 4 each group), generated by microarray specific for LncRNAs which includes corresponding mRNA expressions. In silico analyses of the cellular processes that are impacted by these LncRNAs was performed using Gene Ontology (GO). A selected subset of LncRNAs were validated by quantitative real-time PCR. RESULTS We have identified 636 LncRNAs differentially expressed in CF airway epithelium and 1974 in CF lung parenchyma compared to matched non-CF controls (fold change ≥2, p < 0.05), majority of which (> 50%) are intergenic. Interestingly, 15 of these differentially expressed LncRNAs and 9 coding mRNAs are common to airway and parenchyma tissues. GO analyses indicates that signaling pathways and cell membrane functions are significantly affected by the alteration in LncRNA expressions in CF lung tissues. Seven of the differentially expressed LncRNAs, exhibit similar expression trends in CFBE41o- compared to control cells. CONCLUSION Understanding the mechanisms by which these LncRNAs regulate CF disease phenotype will help develop novel therapeutic targets for CF and related pulmonary diseases, such as COPD and Asthma.
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Affiliation(s)
- Parameet Kumar
- Department of Anatomy, Physiology and Genetics, School of Medicine, Uniformed Services University of the Health Sciences, Room B4024, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA
| | - Chaitali Sen
- Department of Anatomy, Physiology and Genetics, School of Medicine, Uniformed Services University of the Health Sciences, Room B4024, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA
| | - Kathryn Peters
- Departments of Pediatrics and Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, 15261, USA
| | - Raymond A Frizzell
- Departments of Pediatrics and Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, 15261, USA
| | - Roopa Biswas
- Department of Anatomy, Physiology and Genetics, School of Medicine, Uniformed Services University of the Health Sciences, Room B4024, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA.
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19
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Membrane-associated RING-CH (MARCH) proteins down-regulate cell surface expression of the interleukin-6 receptor alpha chain (IL6Rα). Biochem J 2019; 476:2869-2882. [DOI: 10.1042/bcj20190577] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/04/2019] [Accepted: 09/05/2019] [Indexed: 01/13/2023]
Abstract
Abstract
Interleukin 6 (IL6) is a cytokine that regulates a number of important immune and inflammatory pathways. We used the ability of IL6 to inhibit the clonal proliferation of the mouse M1 myeloid leukemia cell line in agar to positively screen a cDNA expression library for proteins that inhibited IL6 activity. We found three clones completely resistant to IL6 that contained the cDNA for the Membrane-Associated RING-CH E3 ubiquitin ligase MARCH2. MARCH2 is a member of a family of membrane-bound E3 ubiquitin ligases that target cell surface receptors for degradation. MARCH2 overexpressing M1 clones retained responsiveness to the related cytokines leukemia inhibitory factor and oncostatin M and we showed that its inhibitory effect was a result of selective down-regulation of the IL6 receptor alpha chain and not the shared receptor subunit, gp130 or other signalling molecules. This activity of MARCH2 was also shared with related proteins MARCH4, MARCH9 and an isoform of MARCH3. The transmembrane domains and C-terminal domains, as well as a functional RING domain, of MARCH proteins were all required for substrate recognition and down-regulation. Genetic deletion of individual MARCH proteins in mice had no or little effect on IL6Rα levels but combined deletions of MARCH2,3 and 4 displayed elevated steady-state levels of IL6Rα in selected haemopoietic cell subsets including CD8+ and CD4+ T cells. These studies extend the potential immunosuppressive roles of MARCH proteins to include down-regulation of IL6 inflammatory responses.
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20
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Li DT, Habtemichael EN, Julca O, Sales CI, Westergaard XO, DeVries SG, Ruiz D, Sayal B, Bogan JS. GLUT4 Storage Vesicles: Specialized Organelles for Regulated Trafficking. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:453-470. [PMID: 31543708 PMCID: PMC6747935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Fat and muscle cells contain a specialized, intracellular organelle known as the GLUT4 storage vesicle (GSV). Insulin stimulation mobilizes GSVs, so that these vesicles fuse at the cell surface and insert GLUT4 glucose transporters into the plasma membrane. This example is likely one instance of a broader paradigm for regulated, non-secretory exocytosis, in which intracellular vesicles are translocated in response to diverse extracellular stimuli. GSVs have been studied extensively, yet these vesicles remain enigmatic. Data support the view that in unstimulated cells, GSVs are present as a pool of preformed small vesicles, which are distinct from endosomes and other membrane-bound organelles. In adipocytes, GSVs contain specific cargoes including GLUT4, IRAP, LRP1, and sortilin. They are formed by membrane budding, involving sortilin and probably CHC22 clathrin in humans, but the donor compartment from which these vesicles form remains uncertain. In unstimulated cells, GSVs are trapped by TUG proteins near the endoplasmic reticulum - Golgi intermediate compartment (ERGIC). Insulin signals through two main pathways to mobilize these vesicles. Signaling by the Akt kinase modulates Rab GTPases to target the GSVs to the cell surface. Signaling by the Rho-family GTPase TC10α stimulates Usp25m-mediated TUG cleavage to liberate the vesicles from the Golgi. Cleavage produces a ubiquitin-like protein modifier, TUGUL, that links the GSVs to KIF5B kinesin motors to promote their movement to the cell surface. In obesity, attenuation of these processes results in insulin resistance and contributes to type 2 diabetes and may simultaneously contribute to hypertension and dyslipidemia in the metabolic syndrome.
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Affiliation(s)
- Don T. Li
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT,Department of Cell Biology, Yale University School of Medicine, Yale University, New Haven, CT
| | - Estifanos N. Habtemichael
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT
| | - Omar Julca
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT
| | - Chloe I. Sales
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT
| | - Xavier O. Westergaard
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT
| | - Stephen G. DeVries
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT
| | - Diana Ruiz
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT
| | - Bhavesh Sayal
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT
| | - Jonathan S. Bogan
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, Yale University, New Haven, CT,Department of Cell Biology, Yale University School of Medicine, Yale University, New Haven, CT,To whom all correspondence should be addressed: Jonathan S. Bogan, Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, P.O. Box 208020, New Haven, CT 06520-8020; Tel: 203-785-6319; Fax: 203-785-6462;
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Huang Y, Arora K, Mun KS, Yang F, Moon C, Yarlagadda S, Jegga A, Weaver T, Naren AP. Targeting DNAJB9, a novel ER luminal co-chaperone, to rescue ΔF508-CFTR. Sci Rep 2019; 9:9808. [PMID: 31285458 PMCID: PMC6614449 DOI: 10.1038/s41598-019-46161-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 06/19/2019] [Indexed: 01/30/2023] Open
Abstract
The molecular mechanism of Endoplasmic Reticulum-associated degradation (ERAD) of Cystic fibrosis transmembrane-conductance regulator (CFTR) is largely unknown. Particularly, it is unknown what ER luminal factor(s) are involved in ERAD. Herein, we used ProtoArray to identify an ER luminal co-chaperone, DNAJB9, which can directly interact with CFTR. For both WT- and ΔF508 (deletion of phenylalanine at position 508, the most common CF-causing mutant)-CFTR, knockdown of DNAJB9 by siRNA increased their expression levels on the cell surface and, consequently, upregulated their function. Furthermore, genetic ablation of DNAJB9 in WT mice increased CFTR expression and enhanced CFTR-dependent fluid secretion in enteroids. Importantly, DNAJB9 deficiency upregulated enteroids' fluid secretion in CF mice (homozygous for ΔF508), and silencing one allele of DNAJB9 is sufficient to rescue ΔF508-CFTR in vitro and in vivo, suggesting that DNAJB9 may be a rate-limiting factor in CFTR ERAD pathway. Our studies identified the first ER luminal co-chaperone involved in CFTR ERAD, and DNAJB9 could be a novel therapeutic target for CF.
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Affiliation(s)
- Yunjie Huang
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - Kavisha Arora
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - Kyu Shik Mun
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - Fanmuyi Yang
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - ChangSuk Moon
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - Sunitha Yarlagadda
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - Anil Jegga
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - Timothy Weaver
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States
| | - Anjaparavanda P Naren
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, United States.
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22
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23
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Yoo W, Cho EB, Kim S, Yoon JB. The E3 ubiquitin ligase MARCH2 regulates ERGIC3-dependent trafficking of secretory proteins. J Biol Chem 2019; 294:10900-10912. [PMID: 31142615 DOI: 10.1074/jbc.ra119.007435] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 05/17/2019] [Indexed: 11/06/2022] Open
Abstract
The E3 ubiquitin ligase membrane-associated ring-CH-type finger 2 (MARCH2) is known to be involved in intracellular vesicular trafficking, but its role in the early secretory pathway between the endoplasmic reticulum (ER) and Golgi compartments is largely unknown. Human ER-Golgi intermediate compartment protein 2 (ERGIC2) and ERGIC3 are orthologs of Erv41 and Erv46 in yeast, proteins that form a heteromeric complex, cycle between the ER and Golgi, and function as cargo receptors in both anterograde and retrograde protein trafficking. Here, we report that MARCH2 directs ubiquitination and subsequent degradation of ERGIC3 and that MARCH2 depletion increases endogenous ERGIC3 levels. We provide evidence that the lysine residues at positions 6 and 8 of ERGIC3 are the major sites of MARCH2-mediated ubiquitination. Of note, MARCH2 did not significantly decrease the levels of an ERGIC3 variant with lysine-to-arginine substitutions at residues 6 and 8. We also show that ERGIC3 binds to itself or to ERGIC2, whereas ERGIC2 is unable to interact with itself. Our results indicate that α1-antitrypsin and haptoglobin are likely to be cargo proteins of ERGIC3. We further observed that α1-antitrypsin and haptoglobin specifically bind to ERGIC3 and that ERGIC3 depletion decreases their secretion. Moreover, MARCH2 reduced secretion of α1-antitrypsin and haptoglobin, and coexpression of the ubiquitination-resistant ERGIC3 variant largely restored their secretion, suggesting that MARCH2-mediated ERGIC3 ubiquitination is the major cause of the decrease in trafficking of ERGIC3-binding secretory proteins. Our findings provide detailed insights into the regulation of the early secretory pathway by MARCH2 and into ERGIC3 function.
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Affiliation(s)
- Wonjin Yoo
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea and
| | - Eun-Bee Cho
- Department of Medical Lifesciences, Catholic University of Korea, Seoul 06591, Korea
| | - Sungjoo Kim
- Department of Medical Lifesciences, Catholic University of Korea, Seoul 06591, Korea
| | - Jong-Bok Yoon
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea and.
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24
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Tan C, Byrne EFX, Ah-Cann C, Call MJ, Call ME. A serine in the first transmembrane domain of the human E3 ubiquitin ligase MARCH9 is critical for down-regulation of its protein substrates. J Biol Chem 2018; 294:2470-2485. [PMID: 30554144 DOI: 10.1074/jbc.ra118.004836] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 12/05/2018] [Indexed: 01/29/2023] Open
Abstract
The membrane-associated RING-CH (MARCH) family of membrane-bound E3 ubiquitin ligases regulates the levels of cell-surface membrane proteins, many of which are involved in immune responses. Although their role in ubiquitin-dependent endocytosis and degradation of cell-surface proteins is extensively documented, the features of MARCH proteins and their substrates that drive the molecular recognition events leading to ubiquitin transfer remain poorly defined. In this study, we sought to determine the features of human MARCH9 that are required for regulating the surface levels of its substrate proteins. Consistent with previous studies of other MARCH proteins, we found that susceptibility to MARCH9 activity is encoded in the transmembrane (TM) domains of its substrates. Accordingly, substitutions at specific residues and motifs within MARCH9's TM domains resulted in varying degrees of functional impairment. Most notably, a single serine-to-alanine substitution in the first of its two TM domains rendered MARCH9 completely unable to alter the surface levels of two different substrates: the major histocompatibility class I molecule HLA-A2 and the T-cell co-receptor CD4. Solution NMR analysis of a MARCH9 fragment encompassing the two TM domains and extracellular connecting loop revealed that the residues contributing most to MARCH9 activity are located in the α-helical portions of TM1 and TM2 that are closest to the extracellular face of the lipid bilayer. This observation defines a key region required for substrate regulation. In summary, our biochemical and structural findings demonstrate that specific sequences in the α-helical MARCH9 TM domains make crucial contributions to its ability to down-regulate its protein substrates.
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Affiliation(s)
- Cyrus Tan
- From the Structural Biology Division, The Walter and Eliza Hall Institute of Medical Research, 3052 Parkville, Victoria, Australia.,the Department of Medical Biology, University of Melbourne, 3052 Parkville, Victoria, Australia
| | - Eamon F X Byrne
- the Department of Bioengineering, Stanford University, Stanford, California 94305, and
| | - Casey Ah-Cann
- the Department of Medical Biology, University of Melbourne, 3052 Parkville, Victoria, Australia.,the ACRF Stem Cells and Cancer Division, The Walter and Eliza Hall Institute of Medical Research, 3052 Parkville, Victoria, Australia
| | - Melissa J Call
- From the Structural Biology Division, The Walter and Eliza Hall Institute of Medical Research, 3052 Parkville, Victoria, Australia, .,the Department of Medical Biology, University of Melbourne, 3052 Parkville, Victoria, Australia
| | - Matthew E Call
- From the Structural Biology Division, The Walter and Eliza Hall Institute of Medical Research, 3052 Parkville, Victoria, Australia, .,the Department of Medical Biology, University of Melbourne, 3052 Parkville, Victoria, Australia
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25
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Balázs A, Mall MA. Role of the SLC26A9 Chloride Channel as Disease Modifier and Potential Therapeutic Target in Cystic Fibrosis. Front Pharmacol 2018; 9:1112. [PMID: 30327603 PMCID: PMC6174851 DOI: 10.3389/fphar.2018.01112] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/10/2018] [Indexed: 12/13/2022] Open
Abstract
The solute carrier family 26, member 9 (SLC26A9) is an epithelial chloride channel that is expressed in several organs affected in patients with cystic fibrosis (CF) including the lungs, the pancreas, and the intestine. Emerging evidence suggests SLC26A9 as a modulator of wild-type and mutant CFTR function, and as a potential alternative target to circumvent the basic ion transport defect caused by deficient CFTR-mediated chloride transport in CF. In this review, we summarize in vitro studies that revealed multifaceted molecular and functional interactions between SLC26A9 and CFTR that may be implicated in normal transepithelial chloride secretion in health, as well as impaired chloride/fluid transport in CF. Further, we focus on recent genetic association studies and investigations utilizing genetically modified mouse models that identified SLC26A9 as a disease modifier and supported an important role of this alternative chloride channel in the pathophysiology of several organ manifestations in CF, as well as other chronic lung diseases such as asthma and non-CF bronchiectasis. Collectively, these findings and the overlapping endogenous expression with CFTR suggest SLC26A9 an attractive novel therapeutic target that may be exploited to restore epithelial chloride secretion in patients with CF irrespective of their CFTR genotype. In addition, pharmacological activation of SLC26A9 may help to augment the effect of CFTR modulator therapies in patients with CF carrying responsive mutations such as the most common disease-causing mutation F508del-CFTR. However, future research and development including the identification of compounds that activate SLC26A9-mediated chloride transport are needed to explore this alternative chloride channel as a therapeutic target in CF and potentially other muco-obstructive lung diseases.
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Affiliation(s)
- Anita Balázs
- Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany.,German Center for Lung Research, Giessen, Germany
| | - Marcus A Mall
- Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany.,German Center for Lung Research, Giessen, Germany
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26
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Fukuda R, Okiyoneda T. Peripheral Protein Quality Control as a Novel Drug Target for CFTR Stabilizer. Front Pharmacol 2018; 9:1100. [PMID: 30319426 PMCID: PMC6170605 DOI: 10.3389/fphar.2018.01100] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 09/10/2018] [Indexed: 12/12/2022] Open
Abstract
Conformationally defective cystic fibrosis transmembrane conductance regulator (CFTR) including rescued ΔF508-CFTR is rapidly eliminated from the plasma membrane (PM) even in the presence of a CFTR corrector and potentiator, limiting the therapeutic effort of the combination therapy. CFTR elimination from the PM is determined by the conformation-dependent ubiquitination as a part of the peripheral quality control (PQC) mechanism. Recently, the molecular machineries responsible for the CFTR PQC mechanism which includes molecular chaperones and ubiquitination enzymes have been revealed. This review summarizes the molecular mechanism of the CFTR PQC and discusses the possibility that the peripheral ubiquitination mechanism becomes a novel drug target to develop the CFTR stabilizer as a novel class of CFTR modulator.
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Affiliation(s)
- Ryosuke Fukuda
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Nishinomiya, Japan
| | - Tsukasa Okiyoneda
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Nishinomiya, Japan
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27
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Zhang Y, Lu J, Liu X. MARCH2 is upregulated in HIV-1 infection and inhibits HIV-1 production through envelope protein translocation or degradation. Virology 2018; 518:293-300. [PMID: 29573664 DOI: 10.1016/j.virol.2018.02.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Revised: 02/02/2018] [Accepted: 02/02/2018] [Indexed: 01/09/2023]
Abstract
MARCH2 is one of the MARCH family E3 ligases, which contains eleven members that play pivotal roles in controlling the turn-over of membrane proteins, such as MHC class I, MHC class II, and cell surface receptors. In this study, we found the expression of MARCH2 to be upregulated upon HIV-1 infection. MARCH2 inhibits the production and infection of HIV-1 through ligase activity-dependent envelope protein degradation and/or intracellular retention, a mechanism shared by MARCH8 that also leads to the inhibition of HIV-1 infection. Nevertheless, unlike MARCH8 and other MARCH proteins whose transcription levels are unrelated to viral infection, the expression level of MARCH2 is markedly upregulated upon HIV-1 infection, conferring MARCH2 a unique role in monitoring and regulating the HIV-1 infection-associated process.
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Affiliation(s)
- You Zhang
- State Key Laboratory of Medicinal Chemical Biology, Department of Biochemistry and Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jing Lu
- State Key Laboratory of Medicinal Chemical Biology, Department of Biochemistry and Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Xinqi Liu
- State Key Laboratory of Medicinal Chemical Biology, Department of Biochemistry and Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071, China.
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28
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Okiyoneda T, Veit G, Sakai R, Aki M, Fujihara T, Higashi M, Susuki-Miyata S, Miyata M, Fukuda N, Yoshida A, Xu H, Apaja PM, Lukacs GL. Chaperone-Independent Peripheral Quality Control of CFTR by RFFL E3 Ligase. Dev Cell 2018; 44:694-708.e7. [PMID: 29503157 DOI: 10.1016/j.devcel.2018.02.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 12/28/2017] [Accepted: 01/30/2018] [Indexed: 01/09/2023]
Abstract
The peripheral protein quality control (QC) system removes non-native membrane proteins, including ΔF508-CFTR, the most common CFTR mutant in cystic fibrosis (CF), from the plasma membrane (PM) for lysosomal degradation by ubiquitination. It remains unclear how unfolded membrane proteins are recognized and targeted for ubiquitination and how they are removed from the apical PM. Using comprehensive siRNA screens, we identified RFFL, an E3 ubiquitin (Ub) ligase that directly and selectively recognizes unfolded ΔF508-CFTR through its disordered regions. RFFL retrieves the unfolded CFTR from the PM for lysosomal degradation by chaperone-independent K63-linked poly-ubiquitination. RFFL ablation enhanced the functional expression of cell-surface ΔF508-CFTR in the presence of folding corrector molecules, and this effect was further improved by inhibiting the Hsc70-dependent ubiquitination machinery. We propose that multiple peripheral QC mechanisms evolved to dispose of non-native PM proteins and to preserve cellular proteostasis, even at the cost of eliminating partially functional polypeptides.
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Affiliation(s)
- Tsukasa Okiyoneda
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan; Department of Physiology, McGill University, 3655 Promenade Sir-William-Osler, Montréal, QC H3G 1Y6, Canada.
| | - Guido Veit
- Department of Physiology, McGill University, 3655 Promenade Sir-William-Osler, Montréal, QC H3G 1Y6, Canada
| | - Ryohei Sakai
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Misaki Aki
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Takeshi Fujihara
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Momoko Higashi
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Seiko Susuki-Miyata
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Masanori Miyata
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Norihito Fukuda
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Akihiko Yoshida
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Haijin Xu
- Department of Physiology, McGill University, 3655 Promenade Sir-William-Osler, Montréal, QC H3G 1Y6, Canada
| | - Pirjo M Apaja
- Department of Physiology, McGill University, 3655 Promenade Sir-William-Osler, Montréal, QC H3G 1Y6, Canada
| | - Gergely L Lukacs
- Department of Physiology, McGill University, 3655 Promenade Sir-William-Osler, Montréal, QC H3G 1Y6, Canada; Department of Biochemistry, McGill University, Montréal, QC H3G 1Y6, Canada; Department of GRASP, McGill University, Montréal, QC H3G 1Y6, Canada.
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29
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Lee H, Cheong SM, Han W, Koo Y, Jo SB, Cho GS, Yang JS, Kim S, Han JK. March2 is required for head formation by mediating Dishevelled degradation in concert with Dapper1. Development 2018; 145:dev.143107. [DOI: 10.1242/dev.143107] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 02/21/2018] [Indexed: 11/20/2022]
Abstract
Dishevelled (Dvl/Dsh) is a key scaffold protein that propagates Wnt signaling essential for embryogenesis and homeostasis. However, whether antagonism of Wnt signaling necessary for vertebrate head formation can be achieved through regulation of Dsh protein stability is unclear. Here we show that membrane-associated RING-CH2 (March2), a RING-type E3 ubiquitin ligase, antagonizes Wnt signaling by regulating the turnover of Dsh protein via ubiquitin-mediated lysosomal degradation in prospective head region of Xenopus. We further found that March2 acquires regional and functional specificities for head formation from the Dsh-interacting protein Dapper1 (Dpr1). Dpr1 stabilizes interaction between March2 and Dsh for mediating ubiquitination and subsequent degradation of Dsh protein only in the dorso-animal region of Xenopus embryo. These results suggest that March2 restricts cytosolic pools of Dsh protein and leads to subsequent limitation of Wnt signaling for the precise vertebrate head development.
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Affiliation(s)
- Hyeyoon Lee
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
- Present address: Division of Molecular Embryology, DKFZ-ZMBH Alliance, Deutsches Krebsforschungszentrum (DKFZ), 69120 Heidelberg, Germany
| | - Seong-Moon Cheong
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
- Present address: Department of Neurology, The F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Wonhee Han
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
| | - Youngmu Koo
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
| | - Saet-Byeol Jo
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
| | - Gun-Sik Cho
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
- Present address: Laboratory of Stem Cells, NEXEL, Seoul, Republic of Korea
| | - Jae-Seong Yang
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
- Present address: EMBL/CRG Systems Biology Research Unit, Center for Genomic Regulation, Dr. Aiguader 88, Barcelona, Spain
| | - Sanguk Kim
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
| | - Jin-Kwan Han
- Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 37673, Korea
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30
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Bauer J, Bakke O, Morth JP. Overview of the membrane-associated RING-CH (MARCH) E3 ligase family. N Biotechnol 2017; 38:7-15. [DOI: 10.1016/j.nbt.2016.12.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 12/05/2016] [Accepted: 12/13/2016] [Indexed: 12/17/2022]
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Knockout of MARCH2 inhibits the growth of HCT116 colon cancer cells by inducing endoplasmic reticulum stress. Cell Death Dis 2017; 8:e2957. [PMID: 28749466 PMCID: PMC5584615 DOI: 10.1038/cddis.2017.347] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 06/16/2017] [Accepted: 06/19/2017] [Indexed: 02/06/2023]
Abstract
Membrane-associated RING-CH protein 2 (MARCH2), a member of the MARCH family, functions in vesicle trafficking and autophagy regulation. In this study, we established MARCH2 knockout HCT116 cell lines using CRISPR/Cas9-mediated genome editing to evaluate the role of MARCH2 in colon cancer in vitro and in vivo. Knockout of MARCH2 suppressed cell proliferation, and promoted autophagy, apoptosis and G2/M phase cell cycle arrest. These effects were associated with activation of endoplasmic reticulum (ER) stress. In addition, loss of MARCH2 sensitized HCT116 cells to the chemotherapy drugs etoposide and cisplatin. Moreover, we analyzed the clinical significance of MARCH2 in human colon carcinoma (n=100). High MARCH2 expression was significantly associated with advanced clinicopathological features and poorer overall survival in colon carcinoma. MARCH2 expression correlated negatively with expression of the unfolded protein response molecule p-PERK in colon cancer. Collectively, these data reveal a relationship between MARCH2, ER stress and colon cancer, and indicates MARCH2 may have an important role in the development and progression of colon cancer.
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32
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Bertrand CA, Mitra S, Mishra SK, Wang X, Zhao Y, Pilewski JM, Madden DR, Frizzell RA. The CFTR trafficking mutation F508del inhibits the constitutive activity of SLC26A9. Am J Physiol Lung Cell Mol Physiol 2017; 312:L912-L925. [PMID: 28360110 PMCID: PMC5495941 DOI: 10.1152/ajplung.00178.2016] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 03/22/2017] [Accepted: 03/22/2017] [Indexed: 11/22/2022] Open
Abstract
Several members of the SLC26A family of anion transporters associate with CFTR, forming complexes in which CFTR and SLC26A functions are reciprocally regulated. These associations are thought to be facilitated by PDZ scaffolding interactions. CFTR has been shown to be positively regulated by NHERF-1, and negatively regulated by CAL in airway epithelia. However, it is unclear which PDZ-domain protein(s) interact with SLC26A9, a SLC26A family member found in airway epithelia. We have previously shown that primary, human bronchial epithelia (HBE) from non-CF donors exhibit constitutive anion secretion attributable to SLC26A9. However, constitutive anion secretion is absent in HBE from CF donors. We examined whether changes in SLC26A9 constitutive activity could be attributed to a loss of CFTR trafficking, and what role PDZ interactions played. HEK293 coexpressing SLC26A9 with the trafficking mutant F508del CFTR exhibited a significant reduction in constitutive current compared with cells coexpressing SLC26A9 and wt CFTR. We found that SLC26A9 exhibits complex glycosylation when coexpressed with F508del CFTR, but its expression at the plasma membrane is decreased. SLC26A9 interacted with both NHERF-1 and CAL, and its interaction with both significantly increased with coexpression of wt CFTR. However, coexpression with F508del CFTR only increased SLC26A9's interaction with CAL. Mutation of SLC26A9's PDZ motif decreased this association with CAL, and restored its constitutive activity. Correcting aberrant F508del CFTR trafficking in CF HBE with corrector VX-809 also restored SLC26A9 activity. We conclude that when SLC26A9 is coexpressed with F508del CFTR, its trafficking defect leads to a PDZ motif-sensitive intracellular retention of SLC26A9.
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Affiliation(s)
- Carol A Bertrand
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania;
| | - Shalini Mitra
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Sanjay K Mishra
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Xiaohui Wang
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Yu Zhao
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Joseph M Pilewski
- Department of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; and
| | - Dean R Madden
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Raymond A Frizzell
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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33
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Lopes-Pacheco M. CFTR Modulators: Shedding Light on Precision Medicine for Cystic Fibrosis. Front Pharmacol 2016; 7:275. [PMID: 27656143 PMCID: PMC5011145 DOI: 10.3389/fphar.2016.00275] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 08/11/2016] [Indexed: 12/15/2022] Open
Abstract
Cystic fibrosis (CF) is the most common life-threatening monogenic disease afflicting Caucasian people. It affects the respiratory, gastrointestinal, glandular and reproductive systems. The major cause of morbidity and mortality in CF is the respiratory disorder caused by a vicious cycle of obstruction of the airways, inflammation and infection that leads to epithelial damage, tissue remodeling and end-stage lung disease. Over the past decades, life expectancy of CF patients has increased due to early diagnosis and improved treatments; however, these patients still present limited quality of life. Many attempts have been made to rescue CF transmembrane conductance regulator (CFTR) expression, function and stability, thereby overcoming the molecular basis of CF. Gene and protein variances caused by CFTR mutants lead to different CF phenotypes, which then require different treatments to quell the patients' debilitating symptoms. In order to seek better approaches to treat CF patients and maximize therapeutic effects, CFTR mutants have been stratified into six groups (although several of these mutations present pleiotropic defects). The research with CFTR modulators (read-through agents, correctors, potentiators, stabilizers and amplifiers) has achieved remarkable progress, and these drugs are translating into pharmaceuticals and personalized treatments for CF patients. This review summarizes the main molecular and clinical features of CF, emphasizes the latest clinical trials using CFTR modulators, sheds light on the molecular mechanisms underlying these new and emerging treatments, and discusses the major breakthroughs and challenges to treating all CF patients.
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Affiliation(s)
- Miquéias Lopes-Pacheco
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro Rio de Janeiro, Brazil
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McClure ML, Barnes S, Brodsky JL, Sorscher EJ. Trafficking and function of the cystic fibrosis transmembrane conductance regulator: a complex network of posttranslational modifications. Am J Physiol Lung Cell Mol Physiol 2016; 311:L719-L733. [PMID: 27474090 DOI: 10.1152/ajplung.00431.2015] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 07/26/2016] [Indexed: 12/19/2022] Open
Abstract
Posttranslational modifications add diversity to protein function. Throughout its life cycle, the cystic fibrosis transmembrane conductance regulator (CFTR) undergoes numerous covalent posttranslational modifications (PTMs), including glycosylation, ubiquitination, sumoylation, phosphorylation, and palmitoylation. These modifications regulate key steps during protein biogenesis, such as protein folding, trafficking, stability, function, and association with protein partners and therefore may serve as targets for therapeutic manipulation. More generally, an improved understanding of molecular mechanisms that underlie CFTR PTMs may suggest novel treatment strategies for CF and perhaps other protein conformational diseases. This review provides a comprehensive summary of co- and posttranslational CFTR modifications and their significance with regard to protein biogenesis.
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Affiliation(s)
- Michelle L McClure
- Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Stephen Barnes
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Eric J Sorscher
- Department of Pediatrics, Emory University, Atlanta, Georgia
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Xia D, Qu L, Li G, Hongdu B, Xu C, Lin X, Lou Y, He Q, Ma D, Chen Y. MARCH2 regulates autophagy by promoting CFTR ubiquitination and degradation and PIK3CA-AKT-MTOR signaling. Autophagy 2016; 12:1614-30. [PMID: 27308891 DOI: 10.1080/15548627.2016.1192752] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
MARCH2 (membrane-associated RING-CH protein 2), an E3 ubiquitin ligase, is mainly associated with the vesicle trafficking. In the present study, for the first time, we demonstrated that MARCH2 negatively regulates autophagy. Our data indicated that overexpression of MARCH2 impaired autophagy, as evidenced by attenuated levels of LC3B-II and impaired degradation of endogenous and exogenous autophagic substrates. By contrast, loss of MARCH2 expression had the opposite effects. In vivo experiments demonstrate that MARCH2 knockout mediated autophagy results in an inhibition of tumorigenicity. Further investigation revealed that the induction of autophagy by MARCH2 deficiency was mediated through the PIK3CA-AKT-MTOR signaling pathway. Additionally, we found that MARCH2 interacts with CFTR (cystic fibrosis transmembrane conductance regulator), promotes the ubiquitination and degradation of CFTR, and inhibits CFTR-mediated autophagy in tumor cells. The functional PDZ domain of MARCH2 is required for the association with CFTR. Thus, our study identified a novel negative regulator of autophagy and suggested that the physical and functional connection between the MARCH2 and CFTR in different conditions will be elucidated in the further experiments.
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Affiliation(s)
- Dan Xia
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
| | - Liujing Qu
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
| | - Ge Li
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
| | - Beiqi Hongdu
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
| | - Chentong Xu
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
| | - Xin Lin
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
| | - Yaxin Lou
- d Medical and Healthy Analytical Center, Peking University , Beijing , China
| | - Qihua He
- d Medical and Healthy Analytical Center, Peking University , Beijing , China
| | - Dalong Ma
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
| | - Yingyu Chen
- a Department of Immunology , Peking University School of Basic Medical Sciences , Beijing , China.,b Key Laboratory of Medical Immunology, Ministry of Health, Peking University Health Sciences Center , Beijing , China.,c Center for Human Disease Genomics, Peking University , Beijing , China
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Bali V, Lazrak A, Guroji P, Matalon S, Bebok Z. Mechanistic Approaches to Improve Correction of the Most Common Disease-Causing Mutation in Cystic Fibrosis. PLoS One 2016; 11:e0155882. [PMID: 27214033 PMCID: PMC4877091 DOI: 10.1371/journal.pone.0155882] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 05/05/2016] [Indexed: 12/28/2022] Open
Abstract
The most common mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene leads to deletion of the phenylalanine at position 508 (ΔF508) in the CFTR protein and causes multiple folding and functional defects. Contrary to large-scale efforts by industry and academia, no significant therapeutic benefit has been achieved with a single “corrector”. Therefore, investigations concentrate on drug combinations. Orkambi (Vertex Pharmaceuticals), the first FDA-approved drug for treatment of cystic fibrosis (CF) caused by this mutation, is a combination of a corrector (VX-809) that facilitates ΔF508 CFTR biogenesis and a potentiator (VX-770), which improves its function. Yet, clinical trials utilizing this combination showed only modest therapeutic benefit. The low efficacy Orkambi has been attributed to VX-770-mediated destabilization of VX-809-rescued ΔF508 CFTR. Here we report that the negative effects of VX-770 can be reversed by increasing the half-life of the endoplasmic reticulum (ER) form (band B) of ΔF508 CFTR with another corrector (Corr-4a.) Although Corr-4a alone has only minimal effects on ΔF508 CFTR rescue, it increases the half-life of ΔF508 CFTR band B when it is present during half-life measurements. Our data shows that stabilization of band B ΔF508 CFTR with Corr-4a and simultaneous rescue with VX-809, leads to a >2-fold increase in cAMP-activated, CFTRinh-172-inhibited currents compared to VX-809 alone, or VX-809+VX-770. The negative effects of VX-770 and the Corr-4a protection are specific to the native I507-ATT ΔF508 CFTR without affecting the inherently more stable, synonymous variant I507-ATC ΔF508 CFTR. Our studies emphasize that stabilization of ΔF508 CFTR band B in the ER might improve its functional rescue by Orkambi.
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Affiliation(s)
- Vedrana Bali
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Ahmed Lazrak
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Lung Injury and Repair Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Purushotham Guroji
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Sadis Matalon
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Lung Injury and Repair Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Zsuzsanna Bebok
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Lung Injury and Repair Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- * E-mail:
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Palma AG, Galizia L, Kotsias BA, Marino GI. CFTR channel in oocytes from Xenopus laevis and its regulation by xShroom1 protein. Pflugers Arch 2016; 468:871-80. [PMID: 26888038 DOI: 10.1007/s00424-016-1800-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 01/18/2016] [Accepted: 02/10/2016] [Indexed: 01/24/2023]
Abstract
Shroom is a family of related proteins linked to the actin cytoskeleton. xShroom1 is constitutively expressed in Xenopus laevis oocytes, and it is required for the expression of the epithelial sodium channel (ENaC). As there is a close relationship between ENaC and the cystic fibrosis transmembrane regulator (CFTR), we examined the action of xShroom1 on CFTR expression and activity. Biotinylation was used to measure CFTR surface expression, and currents were registered with voltage clamp when stimulated with forskolin and 3-isobutyl-1-methylxanthine. Oocytes were coinjected with CFTR complementary RNAs (cRNAs) and xShroom1 sense or antisense oligonucleotides. We observed an increment in CFTR currents and CFTR surface expression in oocytes coinjected with CFTR and xShroom1 antisense oligonucleotides. MG-132, a proteasome inhibitor, did not prevent the increment in currents when xShroom1 was suppressed by antisense oligonucleotides. In addition, we inhibited the delivery of newly synthesized proteins to the plasma membrane with BFA and we found that the half-life of plasma membrane CFTR was prolonged when coinjected with the xShroom1 antisense oligonucleotides. Chloroquine, an inhibitor of the late endosome/lysosome, did not significantly increase CFTR currents when xShroom1 expression was inhibited. The higher expression of CFTR when xShroom1 is suppressed is in concordance with the functional studies suggesting that the suppression of the xShroom1 protein resulted in an increment in CFTR currents by promoting the increase of the half-life of CFTR in the plasma membrane. The role of xShroom1 in regulating CFTR expression could be relevant in the understanding of the channel malfunction in several diseases.
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Affiliation(s)
- Alejandra G Palma
- Laboratorio de Canales Iónicos, Instituto de Investigaciones Médicas Alfredo Lanari, Universidad de Buenos Aires, IDIM-CONICET, C. de Malvinas 3150, 1427, Buenos Aires, Argentina
| | - Luciano Galizia
- Laboratorio de Canales Iónicos, Instituto de Investigaciones Médicas Alfredo Lanari, Universidad de Buenos Aires, IDIM-CONICET, C. de Malvinas 3150, 1427, Buenos Aires, Argentina
| | - Basilio A Kotsias
- Laboratorio de Canales Iónicos, Instituto de Investigaciones Médicas Alfredo Lanari, Universidad de Buenos Aires, IDIM-CONICET, C. de Malvinas 3150, 1427, Buenos Aires, Argentina
| | - Gabriela I Marino
- Laboratorio de Canales Iónicos, Instituto de Investigaciones Médicas Alfredo Lanari, Universidad de Buenos Aires, IDIM-CONICET, C. de Malvinas 3150, 1427, Buenos Aires, Argentina.
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Sun L, Zheng J, Wang Q, Song R, Liu H, Meng R, Tao T, Si Y, Jiang W, He J. NHERF1 regulates actin cytoskeleton organization through modulation of α-actinin-4 stability. FASEB J 2015; 30:578-89. [PMID: 26432781 DOI: 10.1096/fj.15-275586] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 09/21/2015] [Indexed: 01/12/2023]
Abstract
The actin cytoskeleton is composed of a highly dynamic network of filamentous proteins, yet the molecular mechanism that regulates its organization and remodeling remains elusive. In this study, Na(+)/H(+) exchanger regulatory factor (NHERF)-1 loss-of-function and gain-of-function experiments reveal that polymerized actin cytoskeleton (F-actin) in HeLa cells is disorganized by NHERF1, whereas actin protein expression levels exhibit no detectable change. To elucidate the molecular mechanism underlying actin cytoskeleton disorganization by NHERF1, a combined 2-dimensional electrophoresis-matrix-assisted laser desorption/ionization-time of flight mass spectrometry approach was used to screen for proteins regulated by NHERF1 in HeLa cells. α-Actinin-4, an actin cross-linking protein, was identified. Glutathione S-transferase pull-down and coimmunoprecipitation studies showed the α-actinin-4 carboxyl-terminal region specifically interacted with the NHERF1 postsynaptic density 95/disc-large/zona occludens-1 domain. The NHERF1/α-actinin-4 interaction increased α-actinin-4 ubiquitination and decreased its expression levels, resulting in actin cytoskeleton disassembly. Our study identified α-actinin-4 as a novel NHERF1 interaction partner and provided new insights into the regulatory mechanism of the actin cytoskeleton by NHERF1.
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Affiliation(s)
- Licui Sun
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Junfang Zheng
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Qiqi Wang
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Ran Song
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Hua Liu
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Ran Meng
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Tao Tao
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Yang Si
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Wenguo Jiang
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Junqi He
- *Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, China; Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University-Cardiff University Joint Centre for Biomedical Research, Cancer Institute of Capital Medical University, Beijing, China; and Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
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Liu Y, Ao X, Jia Z, Bai XY, Xu Z, Hu G, Jiang X, Chen M, Wu H. FOXK2 transcription factor suppresses ERα-positive breast cancer cell growth through down-regulating the stability of ERα via mechanism involving BRCA1/BARD1. Sci Rep 2015; 5:8796. [PMID: 25740706 PMCID: PMC4350111 DOI: 10.1038/srep08796] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 02/04/2015] [Indexed: 01/05/2023] Open
Abstract
Estrogen receptors (ERs) are critical regulators of breast cancer development. Identification of molecules that regulate the function of ERs may facilitate the development of more effective breast cancer treatment strategies. In this study, we showed that the forkhead transcription factor FOXK2 interacted with ERα, and inhibited ERα-regulated transcriptional activities by enhancing the ubiquitin-mediated degradation of ERα. This process involved the interaction between FOXK2 and BRCA1/BARD1, the E3 ubiquitin ligase of ERα. FOXK2 interacted with BARD1 and acted as a scaffold protein for BRCA1/BARD1 and ERα, leading to enhanced degradation of ERα, which eventually accounted for its decreased transcriptional activity. Consistent with these observations, overexpression of FOXK2 inhibited the transcriptional activity of ERα, decreased the transcription of ERα target genes, and suppressed the proliferation of ERα-positive breast cancer cells. In contract, knockdown of FOXK2 in MCF-7 cells promoted cell proliferation. However, when ERα was also knocked down, knockdown of FOXK2 had no effect on cell proliferation. These findings suggested that FOXK2 might act as a negative regulator of ERα, and its association with both ERα and BRCA1/BARD1 could lead to the down-regulation of ERα transcriptional activity, effectively regulating the function of ERα.
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Affiliation(s)
- Ying Liu
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Xiang Ao
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Zhaojun Jia
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Xiao-Yan Bai
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Zhaowei Xu
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Gaolei Hu
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Xiao Jiang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Min Chen
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China
| | - Huijian Wu
- 1] School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China [2] School of Life Science and Medicine, Dalian University of Technology, Panjin 114221, Liaoning, China
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The Membrane Associated RING-CH Proteins: A Family of E3 Ligases with Diverse Roles through the Cell. INTERNATIONAL SCHOLARLY RESEARCH NOTICES 2014; 2014:637295. [PMID: 27419207 PMCID: PMC4897099 DOI: 10.1155/2014/637295] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 08/22/2014] [Indexed: 01/03/2023]
Abstract
Since the discovery that conjugation of ubiquitin to proteins can drive proteolytic degradation, ubiquitination has been shown to perform a diverse range of functions in the cell. It plays an important role in endocytosis, signal transduction, trafficking of vesicles inside the cell, and even DNA repair. The process of ubiquitination-mediated control has turned out to be remarkably complex, involving a diverse array of proteins and many levels of control. This review focuses on a family of structurally related E3 ligases termed the membrane-associated RING-CH (MARCH) ubiquitin ligases, which were originally discovered as structural homologs to the virals E3s, K3, and K5 from Kaposi's sarcoma-associated herpesvirus (KSHV). These proteins contain a catalytic RING-CH finger and are typically membrane-bound, with some having up to 14 putative transmembrane domains. Despite several lines of evidence showing that the MARCH proteins play a complex and essential role in several cellular processes, this family remains understudied.
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Chaperoning proteins for destruction: diverse roles of Hsp70 chaperones and their co-chaperones in targeting misfolded proteins to the proteasome. Biomolecules 2014; 4:704-24. [PMID: 25036888 PMCID: PMC4192669 DOI: 10.3390/biom4030704] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/31/2014] [Accepted: 06/24/2014] [Indexed: 01/04/2023] Open
Abstract
Molecular chaperones were originally discovered as heat shock-induced proteins that facilitate proper folding of proteins with non-native conformations. While the function of chaperones in protein folding has been well documented over the last four decades, more recent studies have shown that chaperones are also necessary for the clearance of terminally misfolded proteins by the Ub-proteasome system. In this capacity, chaperones protect misfolded degradation substrates from spontaneous aggregation, facilitate their recognition by the Ub ligation machinery and finally shuttle the ubiquitylated substrates to the proteasome. The physiological importance of these functions is manifested by inefficient proteasomal degradation and the accumulation of protein aggregates during ageing or in certain neurodegenerative diseases, when chaperone levels decline. In this review, we focus on the diverse roles of stress-induced chaperones in targeting misfolded proteins to the proteasome and the consequences of their compromised activity. We further discuss the implications of these findings to the identification of new therapeutic targets for the treatment of amyloid diseases.
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Pranke IM, Sermet-Gaudelus I. Biosynthesis of cystic fibrosis transmembrane conductance regulator. Int J Biochem Cell Biol 2014; 52:26-38. [DOI: 10.1016/j.biocel.2014.03.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 03/19/2014] [Accepted: 03/20/2014] [Indexed: 01/19/2023]
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Piper RC, Dikic I, Lukacs GL. Ubiquitin-dependent sorting in endocytosis. Cold Spring Harb Perspect Biol 2014; 6:6/1/a016808. [PMID: 24384571 DOI: 10.1101/cshperspect.a016808] [Citation(s) in RCA: 149] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
When ubiquitin (Ub) is attached to membrane proteins on the plasma membrane, it directs them through a series of sorting steps that culminate in their delivery to the lumen of the lysosome where they undergo complete proteolysis. Ubiquitin is recognized by a series of complexes that operate at a number of vesicle transport steps. Ubiquitin serves as a sorting signal for internalization at the plasma membrane and is the major signal for incorporation into intraluminal vesicles of multivesicular late endosomes. The sorting machineries that catalyze these steps can bind Ub via a variety of Ub-binding domains. At the same time, many of these complexes are themselves ubiquitinated, thus providing a plethora of potential mechanisms to regulate their activity. Here we provide an overview of how membrane proteins are selected for ubiquitination and deubiquitination within the endocytic pathway and how that ubiquitin signal is interpreted by endocytic sorting machineries.
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Affiliation(s)
- Robert C Piper
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
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