1
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Dessaux C, Ganier L, Guiraud L, Borg JP. Recent insights into the therapeutic strategies targeting the pseudokinase PTK7 in cancer. Oncogene 2024; 43:1973-1984. [PMID: 38773263 PMCID: PMC11196218 DOI: 10.1038/s41388-024-03060-x] [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: 03/12/2024] [Revised: 05/02/2024] [Accepted: 05/03/2024] [Indexed: 05/23/2024]
Abstract
The generation of drugs counteracting deregulated protein kinases has been a major focus in cancer therapy development. Breakthroughs in this effort have produced many therapeutic agents to the benefit of patients, mostly through the development of chemical or antibody-based drugs targeting active kinases. These strategies are challenged when considering catalytically inactive protein kinases (or pseudokinases), which represent 10% of the human kinome with many of relevance in cancer. Among the so-called pseudotyrosine kinases, the PTK7 receptor tyrosine kinase (RTK) stands as a bona fide target overexpressed in several solid tumors and hematological malignancies and linked to metastasis, poor prognosis, and resistance to treatment. Despite the lack of catalytic activity, PTK7 has signaling capacities through heterodimerization with active RTKs and offers pharmacological targeting opportunities through its inactive kinase domain. Moreover, PTK7-targeting strategies based on antibody-drug conjugates, aptamers, and CAR-T cell-based therapies have demonstrated encouraging results in preclinical and clinical settings. We review the most recent data assigning to PTK7 a prominent role in cancer progression as well as current preclinical and clinical targeting strategies against RTK family pseudokinases including PTK7.
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Affiliation(s)
- Charlotte Dessaux
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Equipe labellisée Ligue 'Cell polarity, Cell signaling and Cancer', Marseille, France
| | - Laetitia Ganier
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Equipe labellisée Ligue 'Cell polarity, Cell signaling and Cancer', Marseille, France
- adMare BioInnovations, Vancouver, BC, Canada
| | - Louis Guiraud
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Equipe labellisée Ligue 'Cell polarity, Cell signaling and Cancer', Marseille, France
| | - Jean-Paul Borg
- Aix Marseille Univ, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Equipe labellisée Ligue 'Cell polarity, Cell signaling and Cancer', Marseille, France.
- Institut Universitaire de France, Paris, France.
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2
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Vella V, Ditsiou A, Chalari A, Eravci M, Wooller SK, Gagliano T, Bani C, Kerschbamer E, Karakostas C, Xu B, Zhang Y, Pearl FM, Lopez G, Peng L, Stebbing J, Klinakis A, Giamas G. Kinome-Wide Synthetic Lethal Screen Identifies PANK4 as a Modulator of Temozolomide Resistance in Glioblastoma. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306027. [PMID: 38353396 PMCID: PMC11022721 DOI: 10.1002/advs.202306027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 12/23/2023] [Indexed: 02/17/2024]
Abstract
Temozolomide (TMZ) represents the cornerstone of therapy for glioblastoma (GBM). However, acquisition of resistance limits its therapeutic potential. The human kinome is an undisputable source of druggable targets, still, current knowledge remains confined to a limited fraction of it, with a multitude of under-investigated proteins yet to be characterized. Here, following a kinome-wide RNAi screen, pantothenate kinase 4 (PANK4) isuncovered as a modulator of TMZ resistance in GBM. Validation of PANK4 across various TMZ-resistant GBM cell models, patient-derived GBM cell lines, tissue samples, as well as in vivo studies, corroborates the potential translational significance of these findings. Moreover, PANK4 expression is induced during TMZ treatment, and its expression is associated with a worse clinical outcome. Furthermore, a Tandem Mass Tag (TMT)-based quantitative proteomic approach, reveals that PANK4 abrogation leads to a significant downregulation of a host of proteins with central roles in cellular detoxification and cellular response to oxidative stress. More specifically, as cells undergo genotoxic stress during TMZ exposure, PANK4 depletion represents a crucial event that can lead to accumulation of intracellular reactive oxygen species (ROS) and subsequent cell death. Collectively, a previously unreported role for PANK4 in mediating therapeutic resistance to TMZ in GBM is unveiled.
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Affiliation(s)
- Viviana Vella
- Department of Biochemistry and BiomedicineSchool of Life SciencesUniversity of Sussex, FalmerBrightonBN1 9QGUK
| | - Angeliki Ditsiou
- Department of Biochemistry and BiomedicineSchool of Life SciencesUniversity of Sussex, FalmerBrightonBN1 9QGUK
| | - Anna Chalari
- Center of Basic ResearchBiomedical Research Foundation of the Academy of AthensAthens11527Greece
| | - Murat Eravci
- Department of Biochemistry and BiomedicineSchool of Life SciencesUniversity of Sussex, FalmerBrightonBN1 9QGUK
| | - Sarah K. Wooller
- School of Life SciencesBioinformatics GroupUniversity of Sussex, FalmerBrightonBN1 9QGUK
| | | | - Cecilia Bani
- Department of Biochemistry and BiomedicineSchool of Life SciencesUniversity of Sussex, FalmerBrightonBN1 9QGUK
| | | | - Christos Karakostas
- Center of Basic ResearchBiomedical Research Foundation of the Academy of AthensAthens11527Greece
| | - Bin Xu
- Cancer CenterRenmin Hospital of Wuhan UniversityWuhanHubei430064China
| | - Yongchang Zhang
- Department of Medical OncologyLung Cancer and Gastrointestinal UnitHunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South UniversityChangshaHunan430064China
| | - Frances M.G. Pearl
- School of Life SciencesBioinformatics GroupUniversity of Sussex, FalmerBrightonBN1 9QGUK
| | - Gianluca Lopez
- Division of PathologyFondazione IRCCS Ca' Granda – Ospedale Maggiore PoliclinicoMilan20122Italy
- Department of Biomedical, Surgical and Dental SciencesUniversity of MilanMilan20122Italy
| | - Ling Peng
- Department of Respiratory DiseaseZhejiang Provincial People's HospitalHangzhouZhejiang310003China
| | - Justin Stebbing
- Department of Life SciencesAnglia Ruskin UniversityEast RoadCambridgeCB1 1PTUK
| | - Apostolos Klinakis
- Center of Basic ResearchBiomedical Research Foundation of the Academy of AthensAthens11527Greece
| | - Georgios Giamas
- Department of Biochemistry and BiomedicineSchool of Life SciencesUniversity of Sussex, FalmerBrightonBN1 9QGUK
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3
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Lal R, Ritchie J, Richmond L, Keeshan K. Detecting endogenous TRIB2 protein expression by flow cytometry and Western blotting. Methods Enzymol 2022; 667:59-77. [PMID: 35525555 DOI: 10.1016/bs.mie.2022.03.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Protein kinases catalyze the transfer of a phosphate group thereby activating proteins and initiating signaling cascades. Their cousins, the pseudokinases, are enzymatically nonactive counterparts of protein kinases that can be considered zombie enzymes. Interestingly, pseudokinases, which constitute about 10% of the human kinome, have been implicated in many cancers, despite their sequences predicting a lack of catalytic activity. Owing to recent research, it has been demonstrated that dysregulation of many pseudokinases triggers changes in cell signaling, proliferation, and drug resistance. This review is aimed at describing methods that can be used for detection of Tribbles family of pseudokinases, specifically TRIB2. We describe intracellular staining by flow cytometry and Western blotting techniques for the detection of endogenous TRIB2 protein.
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Affiliation(s)
- Ridhima Lal
- Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, SC, United Kingdom
| | - Jake Ritchie
- Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, SC, United Kingdom
| | - Laura Richmond
- Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, SC, United Kingdom
| | - Karen Keeshan
- Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, SC, United Kingdom.
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4
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Paul A, Subhadarshini S, Srinivasan N. Pseudokinases repurpose flexibility signatures associated with the protein kinase fold for noncatalytic roles. Proteins 2021; 90:747-764. [PMID: 34708889 DOI: 10.1002/prot.26271] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/22/2021] [Accepted: 10/18/2021] [Indexed: 01/27/2023]
Abstract
The bilobal protein kinase-like fold in pseudokinases lack one or more catalytic residues, conserved in canonical protein kinases, and are considered enzymatically deficient. Tertiary structures of pseudokinases reveal that their loops topologically equivalent to activation segments of kinases adopt contracted configurations, which is typically extended in active conformation of kinases. Herein, anisotropic network model based normal mode analysis (NMA) was conducted on 51 active conformation structures of protein kinases and 26 crystal structures of pseudokinases. Our observations indicate that although backbone fluctuation profiles are similar for individual kinase-pseudokinase families, low intensity mean square fluctuations in pseudo-activation segment and other sub-structures impart rigidity to pseudokinases. Analyses of collective motions from functional modes reveal that pseudokinases, compared to active kinases, undergo distinct conformational transitions using the same structural fold. All-atom NMA of protein kinase-pseudokinase pairs from each family, sharing high amino acid sequence identities, yielded distinct community clusters, partitioned by residues exhibiting highly correlated fluctuations. It appears that atomic fluctuations from equivalent activation segments guide community membership and network topologies for respective kinase and pseudokinase. Our findings indicate that such adaptations in backbone and side-chain fluctuations render pseudokinases competent for catalysis-independent roles.
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Affiliation(s)
- Anindita Paul
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India
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5
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Paul A, Srinivasan N. Genome-wide and structural analyses of pseudokinases encoded in the genome of Arabidopsis thaliana provide functional insights. Proteins 2020; 88:1620-1638. [PMID: 32667690 DOI: 10.1002/prot.25981] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 05/26/2020] [Accepted: 07/12/2020] [Indexed: 12/31/2022]
Abstract
Protein Kinase-Like Non-Kinases (PKLNKs), commonly known as "pseudokinases", are homologous to eukaryotic Ser/Thr/Tyr protein kinases (PKs) but lack the crucial aspartate residue in the catalytic loop, indispensable for phosphotransferase activity. Therefore, they are predicted to be "catalytically inactive" enzyme homologs. Analysis of protein-kinase like sequences from Arabidopsis thaliana led to the identification of more than 120 pseudokinases lacking catalytic aspartate, majority of which are closely related to the plant-specific receptor-like kinase family. These pseudokinases engage in different biological processes, enabled by their diverse domain architectures and specific subcellular localizations. Structural comparison of pseudokinases with active and inactive conformations of canonical PKs, belonging to both plant and animal origin, revealed unique structural differences. The currently available crystal structures of pseudokinases show that the loop topologically equivalent to activation segment of PKs adopts a distinct-folded conformation, packing against the pseudoenzyme core, in contrast to the extended and inhibitory geometries observed for active and inactive states, respectively, of catalytic PKs. Salt-bridge between ATP-binding Lys and DFG-Asp as well as hydrophobic interactions between the conserved nonpolar residue C-terminal to the equivalent DFG motif and nonpolar residues in C-helix mediate such a conformation in pseudokinases. This results in enhanced solvent accessibility of the pseudocatalytic loop in pseudokinases that can possibly serve as an interacting surface while associating with other proteins. Specifically, our analysis identified several residues that may be involved in pseudokinase regulation and hints at the repurposing of pseudocatalytic residues to achieve mechanistic control over noncatalytic functions of pseudoenzymes.
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Affiliation(s)
- Anindita Paul
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
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6
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Abdeldayem A, Raouf YS, Constantinescu SN, Moriggl R, Gunning PT. Advances in covalent kinase inhibitors. Chem Soc Rev 2020; 49:2617-2687. [DOI: 10.1039/c9cs00720b] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This comprehensive review details recent advances, challenges and innovations in covalent kinase inhibition within a 10 year period (2007–2018).
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Affiliation(s)
- Ayah Abdeldayem
- Department of Chemical & Physical Sciences
- University of Toronto
- Mississauga
- Canada
- Department of Chemistry
| | - Yasir S. Raouf
- Department of Chemical & Physical Sciences
- University of Toronto
- Mississauga
- Canada
- Department of Chemistry
| | | | - Richard Moriggl
- Institute of Animal Breeding and Genetics
- University of Veterinary Medicine
- 1210 Vienna
- Austria
| | - Patrick T. Gunning
- Department of Chemical & Physical Sciences
- University of Toronto
- Mississauga
- Canada
- Department of Chemistry
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7
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Pseudokinases: From Allosteric Regulation of Catalytic Domains and the Formation of Macromolecular Assemblies to Emerging Drug Targets. Catalysts 2019. [DOI: 10.3390/catal9090778] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Pseudokinases are a member of the kinase superfamily that lack one or more of the canonical residues required for catalysis. Protein pseudokinases are widely distributed across species and are present in proteins that perform a great diversity of roles in the cell. They represent approximately 10% to 40% of the kinome of a multicellular organism. In the human, the pseudokinase subfamily consists of approximately 60 unique proteins. Despite their lack of one or more of the amino acid residues typically required for the productive interaction with ATP and metal ions, which is essential for the phosphorylation of specific substrates, pseudokinases are important functional molecules that can act as dynamic scaffolds, competitors, or modulators of protein–protein interactions. Indeed, pseudokinase misfunctions occur in diverse diseases and represent a new therapeutic window for the development of innovative therapeutic approaches. In this contribution, we describe the structural features of pseudokinases that are used as the basis of their classification; analyse the interactome space of human pseudokinases and discuss their potential as suitable drug targets for the treatment of various diseases, including metabolic, neurological, autoimmune, and cell proliferation disorders.
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8
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Plasmodium pseudo-Tyrosine Kinase-like binds PP1 and SERA5 and is exported to host erythrocytes. Sci Rep 2019; 9:8120. [PMID: 31148576 PMCID: PMC6544628 DOI: 10.1038/s41598-019-44542-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 05/15/2019] [Indexed: 01/13/2023] Open
Abstract
Pseudokinases play key roles in many biological processes but they are poorly understood compared to active kinases. Eight putative pseudokinases have been predicted in Plasmodium species. We selected the unique pseudokinase belonging to tyrosine kinase like (TKL) family for detailed structural and functional analysis in P. falciparum and P. berghei. The primary structure of PfpTKL lacks residues critical for kinase activity, supporting its annotation as a pseudokinase. The recombinant pTKL pseudokinase domain was able to bind ATP, but lacked catalytic activity as predicted. The sterile alpha motif (SAM) and RVxF motifs of PfpTKL were found to interact with the P. falciparum proteins serine repeat antigen 5 (SERA5) and protein phosphatase type 1 (PP1) respectively, suggesting that pTKL has a scaffolding role. Furthermore, we found that PP1c activity in a heterologous model was modulated in an RVxF-dependent manner. During the trophozoite stages, PbpTKL was exported to infected erythrocytes where it formed complexes with proteins involved in cytoskeletal organization or host cell maturation and homeostasis. Finally, genetic analysis demonstrated that viable strains obtained by genomic deletion or knocking down PbpTKL did not affect the course of parasite intra-erythrocytic development or gametocyte emergence, indicating functional redundancy during these parasite stages.
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9
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Pseudo-DUBs as allosteric activators and molecular scaffolds of protein complexes. Biochem Soc Trans 2018; 46:453-466. [PMID: 29472364 DOI: 10.1042/bst20160268] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 01/10/2018] [Accepted: 01/13/2018] [Indexed: 12/17/2022]
Abstract
The ubiquitin (Ub) proteasome system and Ub signalling networks are crucial to cell biology and disease development. Deubiquitylases (DUBs) control cell signalling by removing mono-Ub and polyubiquitin chains from substrates. DUBs take part in almost all processes that regulate cellular life and are frequently dysregulated in disease. We have catalogued 99 currently known DUBs in the human genome and sequence conservation analyses of catalytic residues suggest that 11 lack enzyme activity and are classed as pseudo-DUBs. These pseudoenzymes play important biological roles by allosterically activating catalytically competent DUBs as well as other active enzymes. Additionally, pseudoenzymes act as assembly scaffolds of macromolecular complexes. We discuss how pseudo-DUBs have lost their catalytic activity, their diverse mechanisms of action and their potential as therapeutic targets. Many known pseudo-DUBs play crucial roles in cell biology and it is likely that unstudied and overlooked pseudo-DUB genes will have equally important functions.
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10
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Zheng PP, Li J, Kros JM. Breakthroughs in modern cancer therapy and elusive cardiotoxicity: Critical research-practice gaps, challenges, and insights. Med Res Rev 2017; 38:325-376. [PMID: 28862319 PMCID: PMC5763363 DOI: 10.1002/med.21463] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 07/14/2017] [Accepted: 07/15/2017] [Indexed: 12/16/2022]
Abstract
To date, five cancer treatment modalities have been defined. The three traditional modalities of cancer treatment are surgery, radiotherapy, and conventional chemotherapy, and the two modern modalities include molecularly targeted therapy (the fourth modality) and immunotherapy (the fifth modality). The cardiotoxicity associated with conventional chemotherapy and radiotherapy is well known. Similar adverse cardiac events are resurging with the fourth modality. Aside from the conventional and newer targeted agents, even the most newly developed, immune‐based therapeutic modalities of anticancer treatment (the fifth modality), e.g., immune checkpoint inhibitors and chimeric antigen receptor (CAR) T‐cell therapy, have unfortunately led to potentially lethal cardiotoxicity in patients. Cardiac complications represent unresolved and potentially life‐threatening conditions in cancer survivors, while effective clinical management remains quite challenging. As a consequence, morbidity and mortality related to cardiac complications now threaten to offset some favorable benefits of modern cancer treatments in cancer‐related survival, regardless of the oncologic prognosis. This review focuses on identifying critical research‐practice gaps, addressing real‐world challenges and pinpointing real‐time insights in general terms under the context of clinical cardiotoxicity induced by the fourth and fifth modalities of cancer treatment. The information ranges from basic science to clinical management in the field of cardio‐oncology and crosses the interface between oncology and onco‐pharmacology. The complexity of the ongoing clinical problem is addressed at different levels. A better understanding of these research‐practice gaps may advance research initiatives on the development of mechanism‐based diagnoses and treatments for the effective clinical management of cardiotoxicity.
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Affiliation(s)
- Ping-Pin Zheng
- Cardio-Oncology Research Group, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Pathology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Jin Li
- Department of Oncology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Johan M Kros
- Department of Pathology, Erasmus Medical Center, Rotterdam, the Netherlands
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11
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MicroRNA-497 inhibits tumor growth and increases chemosensitivity to 5-fluorouracil treatment by targeting KSR1. Oncotarget 2016; 7:2660-71. [PMID: 26673620 PMCID: PMC4823062 DOI: 10.18632/oncotarget.6545] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 11/16/2015] [Indexed: 12/19/2022] Open
Abstract
Colorectal cancer (CRC) is one of the leading cancer-related causes of death in the world. Recently, downregulation of microRNA-497 (miR-497) has been observed in CRC tissues. In this study, we found that miR-497 expression levels were downregulated in human CRC specimens compared to the adjacent normal tissues. MiR-497 expression levels were strongly correlated with clinical stages and lymph node metastases. Furthermore, kinase suppressor of ras 1 (KSR1), a known oncogene, was a direct target of miR-497, and KSR1 expression levels were inversely correlated with miR-497 expression levels in human CRC specimens. Overexpression of miR-497 inhibited cell proliferation, migration, invasion and increased chemosensitivity to 5-fluorouracil treatment, whereas forced expression of KSR1 had the opposite effect. Taken together, these results revealed that lower miR-497 levels in human CRC tissues induce KSR1 expression which is associated with CRC cancer occurrence, advanced stages, metastasis and chemoresistance. Lower miR-497 levels may be a potential biomarker for CRC advanced stages and treatment response.
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12
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Baljuls A, Dobrzyński M, Rauch J, Rauch N, Kolch W. Stabilization of C-RAF:KSR1 complex by DiRas3 reduces availability of C-RAF for dimerization with B-RAF. Cell Signal 2016; 28:1451-62. [DOI: 10.1016/j.cellsig.2016.06.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 06/18/2016] [Accepted: 06/27/2016] [Indexed: 12/19/2022]
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13
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Hammarén HM, Virtanen AT, Silvennoinen O. Nucleotide-binding mechanisms in pseudokinases. Biosci Rep 2015; 36:e00282. [PMID: 26589967 PMCID: PMC4718504 DOI: 10.1042/bsr20150226] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 11/11/2015] [Accepted: 11/20/2015] [Indexed: 01/01/2023] Open
Abstract
Pseudokinases are classified by the lack of one or several of the highly conserved motifs involved in nucleotide (nt) binding or catalytic activity of protein kinases (PKs). Pseudokinases represent ∼10% of the human kinome and they are found in all evolutionary classes of kinases. It has become evident that pseudokinases, which were initially considered somewhat peculiar dead kinases, are important components in several signalling cascades. Furthermore, several pseudokinases have been linked to human diseases, particularly cancer, which is raising interest for therapeutic approaches towards these proteins. The ATP-binding pocket is a well-established drug target and elucidation of the mechanism and properties of nt binding in pseudokinases is of significant interest and importance. Recent studies have demonstrated that members of the pseudokinase family are very diverse in structure as well as in their ability and mechanism to bind nts or perform phosphoryl transfer reactions. This diversity also precludes prediction of pseudokinase function, or the importance of nt binding for said function, based on primary sequence alone. Currently available data indicate that ∼40% of pseudokinases are able to bind nts, whereas only few are able to catalyse occasional phosphoryl transfer. Pseudokinases employ diverse mechanisms to bind nts, which usually occurs at low, but physiological, affinity. ATP binding serves often a structural role but in most cases the functional roles are not precisely known. In the present review, we discuss the various mechanisms that pseudokinases employ for nt binding and how this often low-affinity binding can be accurately analysed.
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Affiliation(s)
- Henrik M Hammarén
- School of Medicine, University of Tampere, Biokatu 8, FI-33014 Tampere, Finland
| | - Anniina T Virtanen
- School of Medicine, University of Tampere, Biokatu 8, FI-33014 Tampere, Finland
| | - Olli Silvennoinen
- School of Medicine, University of Tampere, Biokatu 8, FI-33014 Tampere, Finland Clinical Hematology, Department of Internal Medicine, Tampere University Hospital, Medisiinarinkatu 3, FI-33520 Tampere, Finland
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14
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Abstract
Tribbles pseudokinase 3 (TRIB3) belongs to the tribbles family of pseudokinases. In this article, we summarize several observation obtained by our laboratories supporting that TRIB3 plays a crucial role in the anti-cancer activity of cannabinoids (a novel family of potential anti-cancer agents derived from marijuana) and that TRIB3 genetic inactivation enhances cancer generation and progression.
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15
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Di Michele M, Stes E, Vandermarliere E, Arora R, Astorga-Wells J, Vandenbussche J, van Heerde E, Zubarev R, Bonnet P, Linders JTM, Jacoby E, Brehmer D, Martens L, Gevaert K. Limited Proteolysis Combined with Stable Isotope Labeling Reveals Conformational Changes in Protein (Pseudo)kinases upon Binding Small Molecules. J Proteome Res 2015; 14:4179-93. [PMID: 26293246 DOI: 10.1021/acs.jproteome.5b00282] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Likely due to conformational rearrangements, small molecule inhibitors may stabilize the active conformation of protein kinases and paradoxically promote tumorigenesis. We combined limited proteolysis with stable isotope labeling MS to monitor protein conformational changes upon binding of small molecules. Applying this method to the human serine/threonine kinase B-Raf, frequently mutated in cancer, we found that binding of ATP or its nonhydrolyzable analogue AMP-PNP, but not ADP, stabilized the structure of both B-Raf(WT) and B-Raf(V600E). The ATP-competitive type I B-Raf inhibitor vemurafenib and the type II inhibitor sorafenib stabilized the kinase domain (KD) but had distinct effects on the Ras-binding domain. Stabilization of the B-Raf(WT) KD was confirmed by hydrogen/deuterium exchange MS and molecular dynamics simulations. Our results are further supported by cellular assays in which we assessed cell viability and phosphorylation profiles in cells expressing B-Raf(WT) or B-Raf(V600E) in response to vemurafenib or sorafenib. Our data indicate that an overall stabilization of the B-Raf structure by specific inhibitors activates MAPK signaling and increases cell survival, helping to explain clinical treatment failure. We also applied our method to monitor conformational changes upon nucleotide binding of the pseudokinase KSR1, which holds high potential for inhibition in human diseases.
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Affiliation(s)
- Michela Di Michele
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Elisabeth Stes
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Elien Vandermarliere
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Rohit Arora
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans , Pôle de chimie, Rue de Chartres, 45100 Orléans, France
| | | | - Jonathan Vandenbussche
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Erika van Heerde
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Roman Zubarev
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet , Scheelelaberatoriet Scheeles väg 2, SE-171 77 Stockholm, Sweden
| | - Pascal Bonnet
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans , Pôle de chimie, Rue de Chartres, 45100 Orléans, France
| | - Joannes T M Linders
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Edgar Jacoby
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Dirk Brehmer
- Oncology Discovery, Janssen Research and Development, A Division of Janssen Pharmaceutica NV , Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Lennart Martens
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
| | - Kris Gevaert
- Department of Medical Protein Research, VIB , A. Baertsoenkaai 3, 9000 Ghent, Belgium.,Department of Biochemistry, Ghent University , A. Baertsoenkaai 3, 9000 Ghent, Belgium
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16
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Hamilton G, Rath B, Klameth L, Hochmair M. Receptor tyrosine kinase expression of circulating tumor cells in small cell lung cancer. Oncoscience 2015; 2:629-34. [PMID: 26328272 PMCID: PMC4549360 DOI: 10.18632/oncoscience.179] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 07/25/2015] [Indexed: 01/22/2023] Open
Abstract
Small cell lung cancer (SCLC) has a poor prognosis and is found disseminated at first presentation in the majority of cases. The cell biological mechanisms underlying metastasis and drug resistance are not clear. SCLC is characterized by high numbers of circulating tumor cells (CTCs) and we were able to expand several CTC lines ex vivo and to relate chitinase-3-like-1/YKL-40 (CHI3L1) as marker. Availability of expanded SCLC CTC cells allowed for a screening of receptor tyrosine kinases (RTKs) expressed. The metastatic CHI3L1-negative SCLC cell line SCLC26A, established from a pleural effusion was used for comparison. The CTC cell line BHGc10 was found to exhibit increased expression of RYK, AXL, Tie-1, Dtk, ROR1/2, several ephrins (Eph) and FGF/EGF receptors compared to SCLC26A. All of these RTKs have been associated with cell motility, invasion and poor prognosis in diverse cancer entities without knowledge of their association with CTCs. The identification of RYK, AXL and ROR1/2 as pseudokinases, lacking activity, seems to be related to the observed failure of RTK inhibitors in SCLC. These kinases are involved in the noncanonical WNT pathway and their expression in SCLC CTCs represents a cancer stem cell-like phenotype.
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Affiliation(s)
- Gerhard Hamilton
- Ludwig Boltzmann Cluster of Translational Oncology, Vienna, Austria
| | - Barbara Rath
- Ludwig Boltzmann Cluster of Translational Oncology, Vienna, Austria
| | - Lukas Klameth
- Ludwig Boltzmann Cluster of Translational Oncology, Vienna, Austria
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17
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Zhang H, Angelopoulos N, Xu Y, Grothey A, Nunes J, Stebbing J, Giamas G. Proteomic profile of KSR1-regulated signalling in response to genotoxic agents in breast cancer. Breast Cancer Res Treat 2015; 151:555-68. [PMID: 26022350 PMCID: PMC4452580 DOI: 10.1007/s10549-015-3443-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 05/22/2015] [Indexed: 12/18/2022]
Abstract
Kinase suppressor of Ras 1 (KSR1) has been implicated in tumorigenesis in multiple cancers, including skin, pancreatic and lung carcinomas. However, our recent study revealed a role of KSR1 as a tumour suppressor in breast cancer, the expression of which is potentially correlated with chemotherapy response. Here, we aimed to further elucidate the KSR1-regulated signalling in response to genotoxic agents in breast cancer. Stable isotope labelling by amino acids in cell culture (SILAC) coupled to high-resolution mass spectrometry (MS) was implemented to globally characterise cellular protein levels induced by KSR1 in the presence of doxorubicin or etoposide. The acquired proteomic signature was compared and GO-STRING analysis was subsequently performed to illustrate the activated functional signalling networks. Furthermore, the clinical associations of KSR1 with identified targets and their relevance in chemotherapy response were examined in breast cancer patients. We reveal a comprehensive repertoire of thousands of proteins identified in each dataset and compare the unique proteomic profiles as well as functional connections modulated by KSR1 after doxorubicin (Doxo-KSR1) or etoposide (Etop-KSR1) stimulus. From the up-regulated top hits, several proteins, including STAT1, ISG15 and TAP1 are also found to be positively associated with KSR1 expression in patient samples. Moreover, high KSR1 expression, as well as high abundance of these proteins, is correlated with better survival in breast cancer patients who underwent chemotherapy. In aggregate, our data exemplify a broad functional network conferred by KSR1 with genotoxic agents and highlight its implication in predicting chemotherapy response in breast cancer.
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Affiliation(s)
- Hua Zhang
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, ICTEM Building, Du Cane Road, London, W12 ONN UK
| | - Nicos Angelopoulos
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, ICTEM Building, Du Cane Road, London, W12 ONN UK
| | - Yichen Xu
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, ICTEM Building, Du Cane Road, London, W12 ONN UK
| | - Arnhild Grothey
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, ICTEM Building, Du Cane Road, London, W12 ONN UK
| | - Joao Nunes
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, ICTEM Building, Du Cane Road, London, W12 ONN UK
| | - Justin Stebbing
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, ICTEM Building, Du Cane Road, London, W12 ONN UK
| | - Georgios Giamas
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, ICTEM Building, Du Cane Road, London, W12 ONN UK
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18
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Salazar M, Lorente M, García-Taboada E, Gómez EP, Dávila D, Zúñiga-García P, Flores JM, Rodríguez A, Hegedus Z, Mosén-Ansorena D, Aransay AM, Hernández-Tiedra S, López-Valero I, Quintanilla M, Sánchez C, Iovanna JL, Dusetti N, Guzmán M, Francis SE, Carracedo A, Kiss-Toth E, Velasco G. TRIB3 suppresses tumorigenesis by controlling mTORC2/AKT/FOXO signaling. Mol Cell Oncol 2015; 2:e980134. [PMID: 27308456 PMCID: PMC4905291 DOI: 10.4161/23723556.2014.980134] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 10/20/2014] [Accepted: 10/21/2014] [Indexed: 11/19/2022]
Abstract
In a recent article, we found that Tribbles pseudokinase 3 (TRIB3) plays a tumor suppressor role and that this effect relies on the dysregulation of the phosphorylation of v-akt murine thymoma viral oncogene homolog (AKT) by the mammalian target of rapamycin complex 2 (mTORC2 complex), and the subsequent hyperphosphorylation and inactivation of the transcription factor Forkhead box O3 (FOXO3).
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Affiliation(s)
- María Salazar
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigaciones Sanitarias San Carlos (IdISSC); Madrid, Spain
| | - Mar Lorente
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigaciones Sanitarias San Carlos (IdISSC); Madrid, Spain
| | - Elena García-Taboada
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University ; Madrid, Spain
| | - Eduardo Pérez Gómez
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigación Hospital 12 de Octubre (I+12); Madrid, Spain
| | - David Dávila
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigaciones Sanitarias San Carlos (IdISSC); Madrid, Spain
| | | | - Juana M Flores
- Department of Animal Surgery and Medicine; School of Veterinary; Complutense University ; Madrid, Spain
| | - Antonio Rodríguez
- Department of Animal Surgery and Medicine; School of Veterinary; Complutense University ; Madrid, Spain
| | - Zoltan Hegedus
- Institute of Biophysics; Hungarian Academy of Sciences ; Szeged, Hungary
| | | | - Ana M Aransay
- CIC bioGUNE-CIBERehd, Bizkaia Technology Park ; Derio, Spain
| | - Sonia Hernández-Tiedra
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigaciones Sanitarias San Carlos (IdISSC); Madrid, Spain
| | - Israel López-Valero
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigaciones Sanitarias San Carlos (IdISSC); Madrid, Spain
| | - Miguel Quintanilla
- Instituto de Investigaciones Biomédicas Alberto Sols; Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM) ; Madrid, Spain
| | - Cristina Sánchez
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigación Hospital 12 de Octubre (I+12); Madrid, Spain
| | - Juan L Iovanna
- Centre de Recherche en Carcérologie de Marseille (CRCM); INSERM UMR 1068, CNRS UMR 7258, Aix Marseille Université and Institut Paoli Calmette ; Marseille, France
| | - Nelson Dusetti
- Centre de Recherche en Carcérologie de Marseille (CRCM); INSERM UMR 1068, CNRS UMR 7258, Aix Marseille Université and Institut Paoli Calmette ; Marseille, France
| | - Manuel Guzmán
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) and Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS); Madrid, Spain
| | - Sheila E Francis
- Department of Cardiovascular Science; University of Sheffield ; Sheffield, UK
| | - Arkaitz Carracedo
- CIC bioGUNE, Bizkaia Technology Park; Derio, Spain; Ikerbasque, Basque Foundation for Science; Bilbao, Spain; Biochemistry and Molecular Biology Department; University of the Basque Country (UPV/EHU); Bilbao, Spain
| | - Endre Kiss-Toth
- Department of Cardiovascular Science; University of Sheffield ; Sheffield, UK
| | - Guillermo Velasco
- Department of Biochemistry and Molecular Biology I; School of Biology; Complutense University; Madrid, Spain; Instituto de Investigaciones Sanitarias San Carlos (IdISSC); Madrid, Spain
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19
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Stebbing J, Zhang H, Xu Y, Lit LC, Green AR, Grothey A, Lombardo Y, Periyasamy M, Blighe K, Zhang W, Shaw JA, Ellis IO, Lenz HJ, Giamas G. KSR1 regulates BRCA1 degradation and inhibits breast cancer growth. Oncogene 2015; 34:2103-14. [PMID: 24909178 DOI: 10.1038/onc.2014.129] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/02/2014] [Accepted: 04/12/2014] [Indexed: 12/16/2022]
Abstract
Kinase suppressor of Ras-1 (KSR1) facilitates signal transduction in Ras-dependent cancers, including pancreatic and lung carcinomas but its role in breast cancer has not been well studied. Here, we demonstrate for the first time it functions as a tumor suppressor in breast cancer in contrast to data in other tumors. Breast cancer patients (n>1000) with high KSR1 showed better disease-free and overall survival, results also supported by Oncomine analyses, microarray data (n=2878) and genomic data from paired tumor and cell-free DNA samples revealing loss of heterozygosity. KSR1 expression is associated with high breast cancer 1, early onset (BRCA1), high BRCA1-associated ring domain 1 (BARD1) and checkpoint kinase 1 (Chk1) levels. Phospho-profiling of major components of the canonical Ras-RAF-mitogen-activated protein kinases pathway showed no significant changes after KSR1 overexpression or silencing. Moreover, KSR1 stably transfected cells formed fewer and smaller size colonies compared to the parental ones, while in vivo mouse model also demonstrated that the growth of xenograft tumors overexpressing KSR1 was inhibited. The tumor suppressive action of KSR1 is BRCA1 dependent shown by 3D-matrigel and soft agar assays. KSR1 stabilizes BRCA1 protein levels by reducing BRCA1 ubiquitination through increasing BARD1 abundance. These data link these proteins in a continuum with clinical relevance and position KSR1 in the major oncoprotein pathways in breast tumorigenesis.
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Affiliation(s)
- J Stebbing
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK
| | - H Zhang
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK
| | - Y Xu
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK
| | - L C Lit
- 1] Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK [2] Faculty of Medicine, Department of Physiology, University of Malaya, Kuala, Lumpur, Malaysia
| | - A R Green
- Department of Cellular Pathology, Queen's Medical Centre, Nottingham University Hospital NHS Trust, Nottingham, UK
| | - A Grothey
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK
| | - Y Lombardo
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK
| | - M Periyasamy
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK
| | - K Blighe
- Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, UK
| | - W Zhang
- Division of Medical Oncology, University of Southern California, Norris Comprehensive Cancer Centre, Keck School of Medicine, Los Angeles, CA, USA
| | - J A Shaw
- Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, UK
| | - I O Ellis
- Faculty of Medicine, Department of Physiology, University of Malaya, Kuala, Lumpur, Malaysia
| | - H J Lenz
- Division of Medical Oncology, University of Southern California, Norris Comprehensive Cancer Centre, Keck School of Medicine, Los Angeles, CA, USA
| | - G Giamas
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Imperial College Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, London, UK
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20
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Monaghan RM, Whitmarsh AJ. A new role for an old enemy. eLife 2015; 4:e06424. [PMID: 25668745 PMCID: PMC4337629 DOI: 10.7554/elife.06424] [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] [Indexed: 11/13/2022] Open
Abstract
Drugs that change the shape of AKT, a protein kinase that promotes tumor growth, may be more effective than drugs that only target its enzymatic activity.
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Affiliation(s)
- Richard M Monaghan
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Alan J Whitmarsh
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom,
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21
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Salazar M, Lorente M, García-Taboada E, Pérez Gómez E, Dávila D, Zúñiga-García P, María Flores J, Rodríguez A, Hegedus Z, Mosén-Ansorena D, Aransay AM, Hernández-Tiedra S, López-Valero I, Quintanilla M, Sánchez C, Iovanna JL, Dusetti N, Guzmán M, Francis SE, Carracedo A, Kiss-Toth E, Velasco G. Loss of Tribbles pseudokinase-3 promotes Akt-driven tumorigenesis via FOXO inactivation. Cell Death Differ 2014; 22:131-44. [PMID: 25168244 DOI: 10.1038/cdd.2014.133] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 07/11/2014] [Accepted: 07/24/2014] [Indexed: 01/08/2023] Open
Abstract
Tribbles pseudokinase-3 (TRIB3) has been proposed to act as an inhibitor of AKT although the precise molecular basis of this activity and whether the loss of TRIB3 contributes to cancer initiation and progression remain to be clarified. In this study, by using a wide array of in vitro and in vivo approaches, including a Trib3 knockout mouse, we demonstrate that TRIB3 has a tumor-suppressing role. We also find that the mechanism by which TRIB3 loss enhances tumorigenesis relies on the dysregulation of the phosphorylation of AKT by the mTORC2 complex, which leads to an enhanced phosphorylation of AKT on Ser473 and the subsequent hyperphosphorylation and inactivation of the transcription factor FOXO3. These observations support the notion that loss of TRIB3 is associated with a more aggressive phenotype in various types of tumors by enhancing the activity of the mTORC2/AKT/FOXO axis.
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Affiliation(s)
- M Salazar
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
| | - M Lorente
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
| | - E García-Taboada
- Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain
| | - E Pérez Gómez
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigación Hospital 12 de Octubre (I+12), Madrid, Spain
| | - D Dávila
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
| | | | - J María Flores
- Department of Animal Surgery and Medicine, School of Veterinary, Complutense University, Madrid, Spain
| | - A Rodríguez
- Department of Animal Surgery and Medicine, School of Veterinary, Complutense University, Madrid, Spain
| | - Z Hegedus
- Institute of Biophysics, Hungarian Academy of Sciences, Szeged, Hungary
| | | | - A M Aransay
- CIC bioGUNE-CIBERehd, Bizkaia Technology Park, Derio, Spain
| | - S Hernández-Tiedra
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
| | - I López-Valero
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
| | - M Quintanilla
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain
| | - C Sánchez
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigación Hospital 12 de Octubre (I+12), Madrid, Spain
| | - J L Iovanna
- Centre de Recherche en Carcérologie de Marseille (CRCM), INSERM UMR, CNRS UMR 7258, Aix Marseille Université and Institut Paoli Calmette, Marseille, France
| | - N Dusetti
- Centre de Recherche en Carcérologie de Marseille (CRCM), INSERM UMR, CNRS UMR 7258, Aix Marseille Université and Institut Paoli Calmette, Marseille, France
| | - M Guzmán
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) and Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | - S E Francis
- Department of Cardiovascular Science, University of Sheffield, Sheffield, UK
| | - A Carracedo
- 1] CIC bioGUNE, Bizkaia Technology Park, Derio, Spain [2] Ikerbasque, Basque Foundation for Science, Bilbao, Spain [3] Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), Bilbao, Spain
| | - E Kiss-Toth
- Department of Cardiovascular Science, University of Sheffield, Sheffield, UK
| | - G Velasco
- 1] Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, Madrid, Spain [2] Instituto de Investigaciones Sanitarias San Carlos (IdISSC), Madrid, Spain
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22
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Gentile A, Lazzari L, Benvenuti S, Trusolino L, Comoglio PM. The ROR1 pseudokinase diversifies signaling outputs in MET-addicted cancer cells. Int J Cancer 2014; 135:2305-16. [DOI: 10.1002/ijc.28879] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 02/21/2014] [Accepted: 03/20/2014] [Indexed: 01/07/2023]
Affiliation(s)
- Alessandra Gentile
- ECMO, Experimental Clinical Molecular Oncology, Candiolo Cancer Institute-FPO, IRCCS; Candiolo (Torino) Italy
| | - Luca Lazzari
- ECMO, Experimental Clinical Molecular Oncology, Candiolo Cancer Institute-FPO, IRCCS; Candiolo (Torino) Italy
| | - Silvia Benvenuti
- ECMO, Experimental Clinical Molecular Oncology, Candiolo Cancer Institute-FPO, IRCCS; Candiolo (Torino) Italy
| | - Livio Trusolino
- ECMO, Experimental Clinical Molecular Oncology, Candiolo Cancer Institute-FPO, IRCCS; Candiolo (Torino) Italy
- Department of Oncology; University of Torino School of Medicine; Torino Italy
| | - Paolo Maria Comoglio
- ECMO, Experimental Clinical Molecular Oncology, Candiolo Cancer Institute-FPO, IRCCS; Candiolo (Torino) Italy
- Department of Oncology; University of Torino School of Medicine; Torino Italy
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23
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Norris-Mullins B, VanderKolk K, Vacchina P, Joyce MV, Morales MA. LmaPA2G4, a homolog of human Ebp1, is an essential gene and inhibits cell proliferation in L. major. PLoS Negl Trop Dis 2014; 8:e2646. [PMID: 24421916 PMCID: PMC3888471 DOI: 10.1371/journal.pntd.0002646] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 12/03/2013] [Indexed: 11/18/2022] Open
Abstract
We have identified LmaPA2G4, a homolog of the human proliferation-associated 2G4 protein (also termed Ebp1), in a phosphoproteomic screening. Multiple sequence alignment and cluster analysis revealed that LmaPA2G4 is a non-peptidase member of the M24 family of metallopeptidases. This pseudoenzyme is structurally related to methionine aminopeptidases. A null mutant system based on negative selection allowed us to demonstrate that LmaPA2G4 is an essential gene in Leishmania major. Over-expression of LmaPA2G4 did not alter cell morphology or the ability to differentiate into metacyclic and amastigote stages. Interestingly, the over-expression affected cell proliferation and virulence in mouse footpad analysis. LmaPA2G4 binds a synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid [poly(I∶C)] as shown in an electrophoretic mobility shift assay (EMSA). Quantitative proteomics revealed that the over-expression of LmaPA2G4 led to accumulation of factors involved in translation initiation and elongation. Significantly, we found a strong reduction of de novo protein biosynthesis in transgenic parasites using a non-radioactive metabolic labeling assay. In conclusion, LmaPA2G4 is an essential gene and is potentially implicated in fundamental biological mechanisms, such as translation, making it an attractive target for therapeutic intervention.
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Affiliation(s)
- Brianna Norris-Mullins
- Eck Institute for Global Health. Department of Biological Sciences. University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Kaitlin VanderKolk
- Eck Institute for Global Health. Department of Biological Sciences. University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Paola Vacchina
- Eck Institute for Global Health. Department of Biological Sciences. University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Michelle V. Joyce
- Mass Spectrometry and Proteomics Facility, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Miguel A. Morales
- Eck Institute for Global Health. Department of Biological Sciences. University of Notre Dame, Notre Dame, Indiana, United States of America
- * E-mail:
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24
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Zhang H, Xu Y, Filipovic A, Lit LC, Koo CY, Stebbing J, Giamas G. SILAC-based phosphoproteomics reveals an inhibitory role of KSR1 in p53 transcriptional activity via modulation of DBC1. Br J Cancer 2013; 109:2675-84. [PMID: 24129246 PMCID: PMC3833216 DOI: 10.1038/bjc.2013.628] [Citation(s) in RCA: 14] [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: 06/11/2013] [Revised: 09/13/2013] [Accepted: 09/18/2013] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND We have previously identified kinase suppressor of ras-1 (KSR1) as a potential regulatory gene in breast cancer. KSR1, originally described as a novel protein kinase, has a role in activation of mitogen-activated protein kinases. Emerging evidence has shown that KSR1 may have dual functions as an active kinase as well as a scaffold facilitating multiprotein complex assembly. Although efforts have been made to study the role of KSR1 in certain tumour types, its involvement in breast cancer remains unknown. METHODS A quantitative mass spectrometry analysis using stable isotope labelling of amino acids in cell culture (SILAC) was implemented to identify KSR1-regulated phosphoproteins in breast cancer. In vitro luciferase assays, co-immunoprecipitation as well as western blotting experiments were performed to further study the function of KSR1 in breast cancer. RESULTS Of significance, proteomic analysis reveals that KSR1 overexpression decreases deleted in breast cancer-1 (DBC1) phosphorylation. Furthermore, we show that KSR1 decreases the transcriptional activity of p53 by reducing the phosphorylation of DBC1, which leads to a reduced interaction of DBC1 with sirtuin-1 (SIRT1); this in turn enables SIRT1 to deacetylate p53. CONCLUSION Our findings integrate KSR1 into a network involving DBC1 and SIRT1, which results in the regulation of p53 acetylation and its transcriptional activity.
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Affiliation(s)
- H Zhang
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 ONN, UK
| | - Y Xu
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 ONN, UK
| | - A Filipovic
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 ONN, UK
| | - L C Lit
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 ONN, UK
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - C-Y Koo
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 ONN, UK
| | - J Stebbing
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 ONN, UK
| | - G Giamas
- Division of Cancer, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 ONN, UK
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25
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Yeung D, Chmielewski D, Mihai C, Agarwal G. Oligomerization of DDR1 ECD affects receptor-ligand binding. J Struct Biol 2013; 183:495-500. [PMID: 23810922 DOI: 10.1016/j.jsb.2013.06.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Revised: 05/15/2013] [Accepted: 06/20/2013] [Indexed: 01/22/2023]
Abstract
Discoidin domain receptor 1 (DDR1) is a widely expressed receptor tyrosine kinase (RTK) which regulates cell differentiation, proliferation and migration and remodeling of the extracellular matrix. Collagen(s) are the only known ligand for DDR1. We have previously reported that collagen stimulation leads to oligomerization of the full length receptor. In this study we investigated the effect of oligomerization of the DDR1 extracellular domain (ECD) pre and post ligand binding. Solid phase binding assays showed that oligomers of recombinant DDR1-Fc bound more strongly to collagen compared to dimeric DDR1-Fc alone. In addition, DDR1-Fc itself could oligomerize upon in-vitro binding to collagen when examined using atomic force microscopy. Inhibition of dynamin mediated receptor endocytosis could prevent ligand induced endocytosis of DDR1b-YFP in live cells. However inhibition of receptor endocytosis did not affect DDR1 oligomerization. In summary our results demonstrate that DDR1 ECD plays a crucial role in receptor oligomerization which mediates high-affinity interactions with its ligand.
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Affiliation(s)
- David Yeung
- Biomedical Engineering Department, 270 Bevis Hall, 1080 Carmack Road, The Ohio State University Columbus, OH 43210, USA
| | - David Chmielewski
- Davis Heart and Lung Research Institute, 473 West 12th Ave., Columbus, OH 43210, USA
| | - Cosmin Mihai
- Davis Heart and Lung Research Institute, 473 West 12th Ave., Columbus, OH 43210, USA
| | - Gunjan Agarwal
- Biomedical Engineering Department, 270 Bevis Hall, 1080 Carmack Road, The Ohio State University Columbus, OH 43210, USA; Davis Heart and Lung Research Institute, 473 West 12th Ave., Columbus, OH 43210, USA.
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26
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Huang XY, Ke AW, Shi GM, Zhang X, Zhang C, Shi YH, Wang XY, Ding ZB, Xiao YS, Yan J, Qiu SJ, Fan J, Zhou J. αB-crystallin complexes with 14-3-3ζ to induce epithelial-mesenchymal transition and resistance to sorafenib in hepatocellular carcinoma. Hepatology 2013; 57:2235-47. [PMID: 23316005 DOI: 10.1002/hep.26255] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 12/13/2012] [Indexed: 12/11/2022]
Abstract
UNLABELLED The overall survival of patients with hepatocellular carcinoma (HCC) remains poor, and the molecular pathogenesis remains incompletely defined in HCC. Here we report that increased expression of αB-Crystallin in human HCC predicts poor survival and disease recurrence after surgery. Multivariate analysis identifies αB-Crystallin expression as an independent predictor for postoperative recurrence and overall survival. We show that elevated expression of αB-Crystallin promotes HCC progression in vivo and in vitro. We demonstrate that αB-Crystallin overexpression fosters HCC progression by inducing epithelial-mesenchymal transition (EMT) in HCC cells through activation of the extracellular-regulated protein kinase (ERK) cascade, which can counteract the effect of sorafenib. αB-Crystallin complexes with and elevates 14-3-3ζ protein, leading to up-regulation of ERK1/2 activity. Moreover, overexpression of αB-Crystallin in HCC cells induces EMT progression through an ERK1/2/Fra-1/slug signaling pathway. Clinically, our data reveal that overexpression of both αB-Crystallin and 14-3-3ζ correlates with the HCC poorest survival outcomes, and sorafenib response is impaired in patients with αB-Crystallin overexpression. CONCLUSION These data suggest that the αB-Crystallin-14-3-3ζ complex acts synergistically to promote HCC progression by constitutively activating ERK signaling. This study reveals αB-Crystallin as a potential therapeutic target for HCC and a biomarker for predicting sorafenib treatment response. (HEPATOLOGY 2013).
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Affiliation(s)
- Xiao-Yong Huang
- Liver Cancer Institute, Zhongshan Hospital, Fudan University; Key Laboratory of Carcinogenesis and Cancer Invasion (Fudan University), Ministry of Education, Shanghai, PR China
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27
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Nozawa K, Ishitani R, Yoshihisa T, Sato M, Arisaka F, Kanamaru S, Dohmae N, Mangroo D, Senger B, Becker HD, Nureki O. Crystal structure of Cex1p reveals the mechanism of tRNA trafficking between nucleus and cytoplasm. Nucleic Acids Res 2013; 41:3901-14. [PMID: 23396276 PMCID: PMC3616705 DOI: 10.1093/nar/gkt010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In all eukaryotes, transcribed precursor tRNAs are maturated by processing and modification processes in nucleus and are transported to the cytoplasm. The cytoplasmic export protein (Cex1p) captures mature tRNAs from the nuclear export receptor (Los1p) on the cytoplasmic side of the nuclear pore complex, and it delivers them to eukaryotic elongation factor 1α. This conserved Cex1p function is essential for the quality control of mature tRNAs to ensure accurate translation. However, the structural basis of how Cex1p recognizes tRNAs and shuttles them to the translational apparatus remains unclear. Here, we solved the 2.2 Å resolution crystal structure of Saccharomyces cerevisiae Cex1p with C-terminal 197 disordered residues truncated. Cex1p adopts an elongated architecture, consisting of N-terminal kinase-like and a C-terminal α-helical HEAT repeat domains. Structure-based biochemical analyses suggested that Cex1p binds tRNAs on its inner side, using the positively charged HEAT repeat surface and the C-terminal disordered region. The N-terminal kinase-like domain acts as a scaffold to interact with the Ran-exportin (Los1p·Gsp1p) machinery. These results provide the structural basis of Los1p·Gsp1p·Cex1p·tRNA complex formation, thus clarifying the dynamic mechanism of tRNA shuttling from exportin to the translational apparatus.
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Affiliation(s)
- Kayo Nozawa
- Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan
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28
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Fu HL, Valiathan RR, Arkwright R, Sohail A, Mihai C, Kumarasiri M, Mahasenan KV, Mobashery S, Huang P, Agarwal G, Fridman R. Discoidin domain receptors: unique receptor tyrosine kinases in collagen-mediated signaling. J Biol Chem 2013; 288:7430-7437. [PMID: 23335507 DOI: 10.1074/jbc.r112.444158] [Citation(s) in RCA: 158] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The discoidin domain receptors (DDRs) are receptor tyrosine kinases that recognize collagens as their ligands. DDRs display unique structural features and distinctive activation kinetics, which set them apart from other members of the kinase superfamily. DDRs regulate cell-collagen interactions in normal and pathological conditions and thus are emerging as major sensors of collagen matrices and potential novel therapeutic targets. New structural and biological information has shed light on the molecular mechanisms that regulate DDR signaling, turnover, and function. This minireview provides an overview of these areas of DDR research with the goal of fostering further investigation of these intriguing and unique receptors.
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Affiliation(s)
- Hsueh-Liang Fu
- Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201
| | - Rajeshwari R Valiathan
- Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201
| | - Richard Arkwright
- Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201
| | - Anjum Sohail
- Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201
| | - Cosmin Mihai
- Davis Heart and Lung Research Institute and Biomedical Engineering Department, Ohio State University, Columbus, Ohio 43210
| | - Malika Kumarasiri
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Kiran V Mahasenan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Paul Huang
- Institute of Cancer Research, Chester Beatty Laboratories, London SW3 6JB, United Kingdom
| | - Gunjan Agarwal
- Davis Heart and Lung Research Institute and Biomedical Engineering Department, Ohio State University, Columbus, Ohio 43210
| | - Rafael Fridman
- Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201.
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H11/HspB8 and Its Herpes Simplex Virus Type 2 Homologue ICP10PK Share Functions That Regulate Cell Life/Death Decisions and Human Disease. Autoimmune Dis 2012; 2012:395329. [PMID: 23056924 PMCID: PMC3463903 DOI: 10.1155/2012/395329] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/20/2012] [Accepted: 08/21/2012] [Indexed: 12/24/2022] Open
Abstract
Small heat shock proteins (sHsp) also known as HspB are a large family of widely expressed proteins that contain a 90 residues domain known as α-crystallin. Here, we focus on the family member H11/HspB8 and its herpes simplex virus type 2 (HSV-2) homologue ICP10PK, and discuss the possible impact of this relationship on human disease. H11/HspB8 and ICP10PK are atypical protein kinases. They share multi-functional activity that encompasses signaling, unfolded protein response (UPR) and the regulation of life cycle potential. In melanocytes H11/HspB8 causes growth arrest. It is silenced in a high proportion of melanoma prostate cancer, Ewing's sarcoma and hematologic malignancies through aberrant DNA methylation. Its restored expression induces cell death and inhibits tumor growth in xenograft models, identifying H11/HspB8 as a tumor suppressor. This function involves the activation of multiple and distinct death pathways, all of which initiate with H11/HspB8-mediated phosphorylation of transforming growth factor β-activated kinase 1 (TAK1). Both ICP10PK and H11/HspB8 were implicated in inflammatory processes that involve dendritic cells activation through Toll-like receptor-dependent pathways and may contribute to the onset of autoimmunity. The potential evolutionary relationship of H11/HspB8 to ICP10PK, its impact on human disorders and the development of therapeutic strategies are discussed.
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