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Liu T, Huang S, Zhang Q, Xia Y, Zhang M, Sun B. Reconciling ASPP-p53 binding mode discrepancies through an ensemble binding framework that bridges crystallography and NMR data. PLoS Comput Biol 2024; 20:e1011519. [PMID: 38324587 PMCID: PMC10878502 DOI: 10.1371/journal.pcbi.1011519] [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: 09/20/2023] [Revised: 02/20/2024] [Accepted: 01/24/2024] [Indexed: 02/09/2024] Open
Abstract
ASPP2 and iASPP bind to p53 through their conserved ANK-SH3 domains to respectively promote and inhibit p53-dependent cell apoptosis. While crystallography has indicated that these two proteins employ distinct surfaces of their ANK-SH3 domains to bind to p53, solution NMR data has suggested similar surfaces. In this study, we employed multi-scale molecular dynamics (MD) simulations combined with free energy calculations to reconcile the discrepancy in the binding modes. We demonstrated that the binding mode based solely on a single crystal structure does not enable iASPP's RT loop to engage with p53's C-terminal linker-a verified interaction. Instead, an ensemble of simulated iASPP-p53 complexes facilitates this interaction. We showed that the ensemble-average inter-protein contacting residues and NMR-detected interfacial residues qualitatively overlap on ASPP proteins, and the ensemble-average binding free energies better match experimental KD values compared to single crystallgarphy-determined binding mode. For iASPP, the sampled ensemble complexes can be grouped into two classes, resembling the binding modes determined by crystallography and solution NMR. We thus propose that crystal packing shifts the equilibrium of binding modes towards the crystallography-determined one. Lastly, we showed that the ensemble binding complexes are sensitive to p53's intrinsically disordered regions (IDRs), attesting to experimental observations that these IDRs contribute to biological functions. Our results provide a dynamic and ensemble perspective for scrutinizing these important cancer-related protein-protein interactions (PPIs).
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Affiliation(s)
- Te Liu
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Sichao Huang
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Qian Zhang
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Yu Xia
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Manjie Zhang
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Bin Sun
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
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2
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Beacham GM, Wei DT, Beyrent E, Zhang Y, Zheng J, Camacho MMK, Florens L, Hollopeter G. The Caenorhabditis elegans ASPP homolog APE-1 is a junctional protein phosphatase 1 modulator. Genetics 2022; 222:iyac102. [PMID: 35792852 PMCID: PMC9434228 DOI: 10.1093/genetics/iyac102] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 06/28/2022] [Indexed: 08/19/2023] Open
Abstract
How serine/threonine phosphatases are spatially and temporally tuned by regulatory subunits is a fundamental question in cell biology. Ankyrin repeat, SH3 domain, proline-rich-region-containing proteins are protein phosphatase 1 catalytic subunit binding partners associated with cardiocutaneous diseases. Ankyrin repeat, SH3 domain, proline-rich-region-containing proteins localize protein phosphatase 1 catalytic subunit to cell-cell junctions, but how ankyrin repeat, SH3 domain, proline-rich-region-containing proteins localize and whether they regulate protein phosphatase 1 catalytic subunit activity in vivo is unclear. Through a Caenorhabditis elegans genetic screen, we find that loss of the ankyrin repeat, SH3 domain, proline-rich-region-containing protein homolog, APE-1, suppresses a pathology called "jowls," providing us with an in vivo assay for APE-1 activity. Using immunoprecipitations and mass spectrometry, we find that APE-1 binds the protein phosphatase 1 catalytic subunit called GSP-2. Through structure-function analysis, we discover that APE-1's N-terminal half directs the APE-1-GSP-2 complex to intercellular junctions. Additionally, we isolated mutations in highly conserved residues of APE-1's ankyrin repeats that suppress jowls yet do not preclude GSP-2 binding, implying APE-1 does more than simply localize GSP-2. Indeed, in vivo reconstitution of APE-1 suggests the ankyrin repeats modulate phosphatase output, a function we find to be conserved among vertebrate homologs.
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Affiliation(s)
| | - Derek T Wei
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Erika Beyrent
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Ying Zhang
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Jian Zheng
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Mari M K Camacho
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Laurence Florens
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Gunther Hollopeter
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
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3
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Gomes AS, Ramos H, Inga A, Sousa E, Saraiva L. Structural and Drug Targeting Insights on Mutant p53. Cancers (Basel) 2021; 13:3344. [PMID: 34283062 PMCID: PMC8268744 DOI: 10.3390/cancers13133344] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 12/20/2022] Open
Abstract
p53 is a transcription factor with a pivotal role in cell homeostasis and fate. Its impairment is a major event in tumor onset and development. In fact, about half of human cancers bear TP53 mutations that not only halt the normal function of p53, but also may acquire oncogenic gain of functions that favor tumorigenesis. Although considered undruggable for a long time, evidence has proven the capability of many compounds to restore a wild-type (wt)-like function to mutant p53 (mutp53). However, they have not reached the clinic to date. Structural studies have strongly contributed to the knowledge about p53 structure, stability, dynamics, function, and regulation. Importantly, they have afforded relevant insights into wt and mutp53 pharmacology at molecular levels, fostering the design and development of p53-targeted anticancer therapies. Herein, we provide an integrated view of mutp53 regulation, particularly focusing on mutp53 structural traits and on targeting agents capable of its reactivation, including their biological, biochemical and biophysical features. With this, we expect to pave the way for the development of improved small molecules that may advance precision cancer therapy by targeting p53.
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Affiliation(s)
- Ana Sara Gomes
- LAQV/REQUIMTE, Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal; (A.S.G.); (H.R.)
| | - Helena Ramos
- LAQV/REQUIMTE, Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal; (A.S.G.); (H.R.)
| | - Alberto Inga
- Laboratory of Transcriptional Networks, Department CIBIO, University of Trento, Via Sommarive 9, 38123 Trento, Italy;
| | - Emília Sousa
- Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal;
- CIIMAR-Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Novo Edifício do Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal
| | - Lucília Saraiva
- LAQV/REQUIMTE, Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal; (A.S.G.); (H.R.)
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4
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Jankauskaite J, Jiménez-García B, Dapkunas J, Fernández-Recio J, Moal IH. SKEMPI 2.0: an updated benchmark of changes in protein-protein binding energy, kinetics and thermodynamics upon mutation. Bioinformatics 2019; 35:462-469. [PMID: 30020414 PMCID: PMC6361233 DOI: 10.1093/bioinformatics/bty635] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 07/17/2018] [Indexed: 11/18/2022] Open
Abstract
Motivation Understanding the relationship between the sequence, structure, binding energy, binding kinetics and binding thermodynamics of protein–protein interactions is crucial to understanding cellular signaling, the assembly and regulation of molecular complexes, the mechanisms through which mutations lead to disease, and protein engineering. Results We present SKEMPI 2.0, a major update to our database of binding free energy changes upon mutation for structurally resolved protein–protein interactions. This version now contains manually curated binding data for 7085 mutations, an increase of 133%, including changes in kinetics for 1844 mutations, enthalpy and entropy changes for 443 mutations, and 440 mutations, which abolish detectable binding. Availability and implementation The database is available as supplementary data and at https://life.bsc.es/pid/skempi2/. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Justina Jankauskaite
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Brian Jiménez-García
- Barcelona Supercomputing Center (BSC), Barcelona, Spain.,Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht, the Netherlands
| | - Justas Dapkunas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Juan Fernández-Recio
- Barcelona Supercomputing Center (BSC), Barcelona, Spain.,Institut de Biologia Molecular de Barcelona (IBMB), CSIC, Barcelona, Spain
| | - Iain H Moal
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridge, UK
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5
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Chen S, Wu J, Zhong S, Li Y, Zhang P, Ma J, Ren J, Tan Y, Wang Y, Au KF, Siebold C, Bond GL, Chen Z, Lu M, Jones EY, Lu X. iASPP mediates p53 selectivity through a modular mechanism fine-tuning DNA recognition. Proc Natl Acad Sci U S A 2019; 116:17470-17479. [PMID: 31395738 PMCID: PMC6717262 DOI: 10.1073/pnas.1909393116] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The most frequently mutated protein in human cancer is p53, a transcription factor (TF) that regulates myriad genes instrumental in diverse cellular outcomes including growth arrest and cell death. Cell context-dependent p53 modulation is critical for this life-or-death balance, yet remains incompletely understood. Here we identify sequence signatures enriched in genomic p53-binding sites modulated by the transcription cofactor iASPP. Moreover, our p53-iASPP crystal structure reveals that iASPP displaces the p53 L1 loop-which mediates sequence-specific interactions with the signature-corresponding base-without perturbing other DNA-recognizing modules of the p53 DNA-binding domain. A TF commonly uses multiple structural modules to recognize its cognate DNA, and thus this mechanism of a cofactor fine-tuning TF-DNA interactions through targeting a particular module is likely widespread. Previously, all tumor suppressors and oncoproteins that associate with the p53 DNA-binding domain-except the oncogenic E6 from human papillomaviruses (HPVs)-structurally cluster at the DNA-binding site of p53, complicating drug design. By contrast, iASPP inhibits p53 through a distinct surface overlapping the E6 footprint, opening prospects for p53-targeting precision medicine to improve cancer therapy.
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Affiliation(s)
- Shuo Chen
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Jiale Wu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Shan Zhong
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Yuntong Li
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Ping Zhang
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Jingyi Ma
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Jingshan Ren
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Yun Tan
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yunhao Wang
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242
| | - Kin Fai Au
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242
- Department of Biostatistics, University of Iowa, Iowa City, IA 52242
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Gareth L Bond
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Zhu Chen
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China;
| | - Min Lu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China;
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom;
| | - Xin Lu
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom;
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6
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Structural basis for activation of plasma-membrane Ca 2+-ATPase by calmodulin. Commun Biol 2018; 1:206. [PMID: 30511020 PMCID: PMC6255812 DOI: 10.1038/s42003-018-0203-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 10/26/2018] [Indexed: 01/17/2023] Open
Abstract
Plasma-membrane Ca2+-ATPases expel Ca2+ from the cytoplasm and are key regulators of Ca2+ homeostasis in eukaryotes. They are autoinhibited under low Ca2+ concentrations. Calmodulin (CaM)-binding to a unique regulatory domain releases the autoinhibition and activates the pump. However, the structural basis for this activation, including the overall structure of this calcium pump and its complex with calmodulin, is unknown. We previously determined the high-resolution structure of calmodulin in complex with the regulatory domain of the plasma-membrane Ca2+-ATPase ACA8 and revealed a bimodular mechanism of calcium control in eukaryotes. Here we show that activation of ACA8 by CaM involves large conformational changes. Combining advanced modeling of neutron scattering data acquired from stealth nanodiscs and native mass spectrometry with detailed dissection of binding constants, we present a structural model for the full-length ACA8 Ca2+ pump in its calmodulin-activated state illustrating a displacement of the regulatory domain from the core enzyme. Julius Nitsche et al. demonstrate that binding of two calmodulin molecules displaces the regulatory domain of the plasma-membrane Ca2+-ATPase ACA8 to fully activate this Ca2+ pump by relieving the autoinhibition. This work provides structural evidence for the previously proposed bimodular activation mechanism.
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7
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Fagerholm R, Khan S, Schmidt MK, GarcClosas M, Heikkilä P, Saarela J, Beesley J, Jamshidi M, Aittomäki K, Liu J, Raza Ali H, Andrulis IL, Beckmann MW, Behrens S, Blows FM, Brenner H, Chang-Claude J, Couch FJ, Czene K, Fasching PA, Figueroa J, Floris G, Glendon G, Guo Q, Hall P, Hallberg E, Hamann U, Holleczek B, Hooning MJ, Hopper JL, Jager A, Kabisch M, Investigators KC, Keeman R, Kosma VM, Lambrechts D, Lindblom A, Mannermaa A, Margolin S, Provenzano E, Shah M, Southey MC, Dennis J, Lush M, Michailidou K, Wang Q, Bolla MK, Dunning AM, Easton DF, Pharoah PD., Chenevix-Trench G, Blomqvist C, Nevanlinna H. TP53-based interaction analysis identifies cis-eQTL variants for TP53BP2, FBXO28, and FAM53A that associate with survival and treatment outcome in breast cancer. Oncotarget 2017; 8:18381-18398. [PMID: 28179588 PMCID: PMC5392336 DOI: 10.18632/oncotarget.15110] [Citation(s) in RCA: 9] [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: 12/21/2016] [Accepted: 01/01/2017] [Indexed: 01/13/2023] Open
Abstract
TP53 overexpression is indicative of somatic TP53 mutations and associates with aggressive tumors and poor prognosis in breast cancer. We utilized a two-stage SNP association study to detect variants associated with breast cancer survival in a TP53-dependent manner. Initially, a genome-wide study (n = 575 cases) was conducted to discover candidate SNPs for genotyping and validation in the Breast Cancer Association Consortium (BCAC). The SNPs were then tested for interaction with tumor TP53 status (n = 4,610) and anthracycline treatment (n = 17,828). For SNPs interacting with anthracycline treatment, siRNA knockdown experiments were carried out to validate candidate genes.In the test for interaction between SNP genotype and TP53 status, we identified one locus, represented by rs10916264 (p(interaction) = 3.44 × 10-5; FDR-adjusted p = 0.0011) in estrogen receptor (ER) positive cases. The rs10916264 AA genotype associated with worse survival among cases with ER-positive, TP53-positive tumors (hazard ratio [HR] 2.36, 95% confidence interval [C.I] 1.45 - 3.82). This is a cis-eQTL locus for FBXO28 and TP53BP2; expression levels of these genes were associated with patient survival specifically in ER-positive, TP53-mutated tumors. Additionally, the SNP rs798755 was associated with survival in interaction with anthracycline treatment (p(interaction) = 9.57 × 10-5, FDR-adjusted p = 0.0130). RNAi-based depletion of a predicted regulatory target gene, FAM53A, indicated that this gene can modulate doxorubicin sensitivity in breast cancer cell lines.If confirmed in independent data sets, these results may be of clinical relevance in the development of prognostic and predictive marker panels for breast cancer.
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Affiliation(s)
- Rainer Fagerholm
- Department of Obstetrics and Gynecology, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
| | - Sofia Khan
- Department of Obstetrics and Gynecology, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
| | - Marjanka K. Schmidt
- Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands
| | - Montserrat GarcClosas
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA
| | - Päivi Heikkilä
- Department of Pathology, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
| | - Jani Saarela
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Finland
| | - Jonathan Beesley
- Department of Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Maral Jamshidi
- Department of Obstetrics and Gynecology, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
| | - Kristiina Aittomäki
- Department of Clinical Genetics, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
| | - Jianjun Liu
- Human Genetics Division, Genome Institute of Singapore, Singapore, Singapore
| | - H. Raza Ali
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, UK
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Irene L. Andrulis
- Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Matthias W. Beckmann
- Department of Gynaecology and Obstetrics, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Comprehensive Cancer Center Erlangen-EMN, Erlangen, Germany
| | - Sabine Behrens
- Division of Cancer Epidemiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Fiona M. Blows
- Centre for Cancer Genetic Epidemiology, Department of Oncology, University of Cambridge, Cambridge, UK
| | - Hermann Brenner
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany
- German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
- Division of Preventive Oncology, German Cancer Research Center (DKFZ) and National Center for Tumor Diseases (NCT), Heidelberg, Germany
| | - Jenny Chang-Claude
- Division of Cancer Epidemiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- University Cancer Center Hamburg (UCCH), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fergus J. Couch
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Kamila Czene
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Peter A. Fasching
- Department of Gynaecology and Obstetrics, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Comprehensive Cancer Center Erlangen-EMN, Erlangen, Germany
- David Geffen School of Medicine, Department of Medicine Division of Hematology and Oncology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Jonine Figueroa
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA
- Usher Institute of Population Health Sciences and Informatics, The University of Edinburgh Medical School, Edinburgh, UK
| | - Giuseppe Floris
- Leuven Multidisciplinary Breast Center, Department of Oncology, KULeuven, Leuven Cancer Institute, University Hospitals Leuven
| | - Gord Glendon
- Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, Canada
| | - Qi Guo
- Centre for Cancer Genetic Epidemiology, Department of Oncology, University of Cambridge, Cambridge, UK
| | - Per Hall
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Emily Hallberg
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - Ute Hamann
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | - Maartje J. Hooning
- Department of Medical Oncology, Family Cancer Clinic, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - John L. Hopper
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global health, The University of Melbourne, Melbourne, Australia
| | - Agnes Jager
- Department of Medical Oncology, Family Cancer Clinic, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Maria Kabisch
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | - Renske Keeman
- Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands
| | - Veli-Matti Kosma
- Cancer Center of Eastern Finland, University of Eastern Finland, Kuopio, Finland
- Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, Kuopio, Finland
- Imaging Center, Department of Clinical Pathology, Kuopio University Hospital, Kuopio, Finland
| | - Diether Lambrechts
- Vesalius Research Center, VIB, Leuven, Belgium
- Laboratory for Translational Genetics, Department of Oncology, University of Leuven, Leuven, Belgium
| | - Annika Lindblom
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Arto Mannermaa
- Cancer Center of Eastern Finland, University of Eastern Finland, Kuopio, Finland
- Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, Kuopio, Finland
- Imaging Center, Department of Clinical Pathology, Kuopio University Hospital, Kuopio, Finland
| | - Sara Margolin
- Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Elena Provenzano
- Department of Oncology, University of Cambridge, Addenbrookes Hospital, Cambridge, UK
- Department of Histopathology, Addenbrookes Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
- Cambridge Experimental Cancer Medicine Centre and NIHR Cambridge Biomedical Research Centre, Cambridge, UK
| | - Mitul Shah
- Centre for Cancer Genetic Epidemiology, Department of Oncology, University of Cambridge, Cambridge, UK
| | - Melissa C. Southey
- Department of Pathology, The University of Melbourne, Melbourne, Australia
| | - Joe Dennis
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Michael Lush
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Kyriaki Michailidou
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- Department of Electron Microscopy/Molecular Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Qin Wang
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Manjeet K. Bolla
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Alison M. Dunning
- Centre for Cancer Genetic Epidemiology, Department of Oncology, University of Cambridge, Cambridge, UK
| | - Douglas F. Easton
- Centre for Cancer Genetic Epidemiology, Department of Oncology, University of Cambridge, Cambridge, UK
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Paul D.P . Pharoah
- Centre for Cancer Genetic Epidemiology, Department of Oncology, University of Cambridge, Cambridge, UK
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | | | - Carl Blomqvist
- Department of Oncology, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
- Department of Oncology, University of Örebro, Örebro, Sweden
| | - Heli Nevanlinna
- Department of Obstetrics and Gynecology, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
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8
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2-Sulfonylpyrimidines: Mild alkylating agents with anticancer activity toward p53-compromised cells. Proc Natl Acad Sci U S A 2016; 113:E5271-80. [PMID: 27551077 DOI: 10.1073/pnas.1610421113] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The tumor suppressor p53 has the most frequently mutated gene in human cancers. Many of p53's oncogenic mutants are just destabilized and rapidly aggregate, and are targets for stabilization by drugs. We found certain 2-sulfonylpyrimidines, including one named PK11007, to be mild thiol alkylators with anticancer activity in several cell lines, especially those with mutationally compromised p53. PK11007 acted by two routes: p53 dependent and p53 independent. PK11007 stabilized p53 in vitro via selective alkylation of two surface-exposed cysteines without compromising its DNA binding activity. Unstable p53 was reactivated by PK11007 in some cancer cell lines, leading to up-regulation of p53 target genes such as p21 and PUMA. More generally, there was cell death that was independent of p53 but dependent on glutathione depletion and associated with highly elevated levels of reactive oxygen species and induction of endoplasmic reticulum (ER) stress, as also found for the anticancer agent PRIMA-1(MET)(APR-246). PK11007 may be a lead for anticancer drugs that target cells with nonfunctional p53 or impaired reactive oxygen species (ROS) detoxification in a wide variety of mutant p53 cells.
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9
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Gibbs EB, Showalter SA. Quantitative biophysical characterization of intrinsically disordered proteins. Biochemistry 2015; 54:1314-26. [PMID: 25631161 DOI: 10.1021/bi501460a] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Intrinsically disordered proteins (IDPs) are broadly defined as protein regions that do not cooperatively fold into a spatially or temporally stable structure. Recent research strongly supports the hypothesis that a conserved functional role for structural disorder renders IDPs uniquely capable of functioning in biological processes such as cellular signaling and transcription. Recently, the frequency of application of rigorous mechanistic biochemistry and quantitative biophysics to disordered systems has increased dramatically. For example, the launch of the Protein Ensemble Database (pE-DB) demonstrates that the potential now exists to refine models for the native state structure of IDPs using experimental data. However, rigorous assessment of which observables place the strongest and least biased constraints on those ensembles is now needed. Most importantly, the past few years have seen strong growth in the number of biochemical and biophysical studies attempting to connect structural disorder with function. From the perspective of equilibrium thermodynamics, there is a clear need to assess the relative significance of hydrophobic versus electrostatic forces in IDP interactions, if it is possible to generalize at all. Finally, kinetic mechanisms that invoke conformational selection and/or induced fit are often used to characterize coupled IDP folding and binding, although application of these models is typically built upon thermodynamic observations. Recently, the reaction rates and kinetic mechanisms of more intrinsically disordered systems have been tested through rigorous kinetic experiments. Motivated by these exciting advances, here we provide a review and prospectus for the quantitative study of IDP structure, thermodynamics, and kinetics.
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Affiliation(s)
- Eric B Gibbs
- Department of Chemistry, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
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10
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Iosub-Amir A, Friedler A. Protein–protein interactions of ASPP2: an emerging therapeutic target. MEDCHEMCOMM 2014. [DOI: 10.1039/c4md00147h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ASPP2 induces apoptosis and is downregulated in many types of cancer, making it a promising target for anti-cancer drugs.
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Affiliation(s)
- Anat Iosub-Amir
- Institute of Chemistry
- The Hebrew University of Jerusalem
- Safra Campus
- Jerusalem 91904, Israel
| | - Assaf Friedler
- Institute of Chemistry
- The Hebrew University of Jerusalem
- Safra Campus
- Jerusalem 91904, Israel
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11
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Mapping the structural and dynamical features of multiple p53 DNA binding domains: insights into loop 1 intrinsic dynamics. PLoS One 2013; 8:e80221. [PMID: 24324553 PMCID: PMC3855832 DOI: 10.1371/journal.pone.0080221] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 09/30/2013] [Indexed: 11/19/2022] Open
Abstract
The transcription factor p53 regulates cellular integrity in response to stress. p53 is mutated in more than half of cancerous cells, with a majority of the mutations localized to the DNA binding domain (DBD). In order to map the structural and dynamical features of the DBD, we carried out multiple copy molecular dynamics simulations (totaling 0.8 μs). Simulations show the loop 1 to be the most dynamic element among the DNA-contacting loops (loops 1-3). Loop 1 occupies two major conformational states: extended and recessed; the former but not the latter displays correlations in atomic fluctuations with those of loop 2 (~24 Å apart). Since loop 1 binds to the major groove whereas loop 2 binds to the minor groove of DNA, our results begin to provide some insight into the possible mechanism underpinning the cooperative nature of DBD binding to DNA. We propose (1) a novel mechanism underlying the dynamics of loop 1 and the possible tread-milling of p53 on DNA and (2) possible mutations on loop 1 residues to restore the transcriptional activity of an oncogenic mutation at a distant site.
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12
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Rotem-Bamberger S, Katz C, Friedler A. Regulation of ASPP2 interaction with p53 core domain by an intramolecular autoinhibitory mechanism. PLoS One 2013; 8:e58470. [PMID: 23472201 PMCID: PMC3589414 DOI: 10.1371/journal.pone.0058470] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 02/06/2013] [Indexed: 11/30/2022] Open
Abstract
ASPP2 is a key protein in regulating apoptosis both in p53-dependent and-independent pathways. The C-terminal part of ASPP2 contains four ankyrin repeats and an SH3 domain (Ank-SH3) that mediate the interactions of ASPP2 with apoptosis related proteins such as p53, Bcl-2 and the p65 subunit of NFκB. p53 core domain (p53CD) binds the n-src loop and the RT loop of ASPP2 SH3. ASPP2 contains a disordered proline rich domain (ASPP2 Pro) that forms an intramolecular autoinhibitory interaction with the Ank-SH3 domains. Here we show how this intramolecular interaction affects the intermolecular interactions of ASPP2 with p53, Bcl-2 and NFkB. We used biophysical methods to obtain better understanding of the relationship between ASPP2 and its partners for getting a comprehensive view on ASPP2 pathways. Fluorescence anisotropy competition experiments revealed that both ASPP2 Pro and p53CD competed for binding the n-src loop of the ASPP2 SH3, indicating regulation of p53CD binding to this loop by ASPP2 Pro. Peptides derived from the ASPP2-binding interface of Bcl-2 did not compete with p53CD or NFkB peptides for binding the ASPP2 n-src loop. However, p53CD displaced the NFκB peptide (residues 303–332) from its complex with ASPP2 Ank-SH3, indicating that NFκB 303–332 and p53CD bind a partly overlapping site in ASPP2 SH3, mostly in the RT loop. These results are in agreement with previous docking studies, which showed that ASPP2 Ank-SH3 binds Bcl-2 and NFκB mostly via distinct sites from p53. However they show some overlap between the binding sites of p53CD and NFkB in ASPP2 Ank-SH3. Our results provide experimental evidence that the intramolecular interaction in ASPP2 regulates its binding to p53CD and that ASPP2 Ank-SH3 binds Bcl-2 and NFκB via distinct sites.
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Affiliation(s)
- Shahar Rotem-Bamberger
- Institute of Chemistry, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Chen Katz
- Institute of Chemistry, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Assaf Friedler
- Institute of Chemistry, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
- * E-mail:
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13
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Canning P, von Delft F, Bullock AN. Structural basis for ASPP2 recognition by the tumor suppressor p73. J Mol Biol 2012; 423:515-27. [PMID: 22917970 PMCID: PMC3472557 DOI: 10.1016/j.jmb.2012.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 08/03/2012] [Accepted: 08/13/2012] [Indexed: 11/27/2022]
Abstract
Tumor suppressors p53, p63 and p73 comprise a family of stress-responsive transcription factors with distinct functions in development and tumor suppression. Most human cancers lose p53 function, yet all three proteins are capable of inducing apoptosis or cellular senescence. Mechanisms are therefore under investigation to activate p73-dependent apoptosis in p53-deficient cancer cells. Significantly, the DNA-binding domain (DBD) of p73 escapes viral oncoproteins and displays an enhanced thermal stability. To further understand the variant features of p73, we solved the high-resolution crystal structure of the p73 DBD as well as its complex with the ankyrin repeat and SH3 domains of the pro-apoptotic factor ASPP2. The p73 structure exhibits the same conserved architecture as p53 but displays a divergent L2 loop, a known site of protein-protein interaction. The loop in p73 is changed by a two-residue insertion that also induces repacking around the site of the p53 mutational hotspot R175. Importantly, the binding of ASPP2 is preserved by conformational changes in both the ankyrin repeat and SH3 domains. These results further highlight the structural variation that impacts p53 family interactions within the p53 interactome.
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Affiliation(s)
| | | | - Alex N. Bullock
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, UK
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14
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Knöll R, Linke WA, Zou P, Miocic S, Kostin S, Buyandelger B, Ku CH, Neef S, Bug M, Schäfer K, Knöll G, Felkin LE, Wessels J, Toischer K, Hagn F, Kessler H, Didié M, Quentin T, Maier LS, Teucher N, Unsöld B, Schmidt A, Birks EJ, Gunkel S, Lang P, Granzier H, Zimmermann WH, Field LJ, Faulkner G, Dobbelstein M, Barton PJR, Sattler M, Wilmanns M, Chien KR. Telethonin deficiency is associated with maladaptation to biomechanical stress in the mammalian heart. Circ Res 2011; 109:758-69. [PMID: 21799151 DOI: 10.1161/circresaha.111.245787] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Telethonin (also known as titin-cap or t-cap) is a 19-kDa Z-disk protein with a unique β-sheet structure, hypothesized to assemble in a palindromic way with the N-terminal portion of titin and to constitute a signalosome participating in the process of cardiomechanosensing. In addition, a variety of telethonin mutations are associated with the development of several different diseases; however, little is known about the underlying molecular mechanisms and telethonin's in vivo function. OBJECTIVE Here we aim to investigate the role of telethonin in vivo and to identify molecular mechanisms underlying disease as a result of its mutation. METHODS AND RESULTS By using a variety of different genetically altered animal models and biophysical experiments we show that contrary to previous views, telethonin is not an indispensable component of the titin-anchoring system, nor is deletion of the gene or cardiac specific overexpression associated with a spontaneous cardiac phenotype. Rather, additional titin-anchorage sites, such as actin-titin cross-links via α-actinin, are sufficient to maintain Z-disk stability despite the loss of telethonin. We demonstrate that a main novel function of telethonin is to modulate the turnover of the proapoptotic tumor suppressor p53 after biomechanical stress in the nuclear compartment, thus linking telethonin, a protein well known to be present at the Z-disk, directly to apoptosis ("mechanoptosis"). In addition, loss of telethonin mRNA and nuclear accumulation of this protein is associated with human heart failure, an effect that may contribute to enhanced rates of apoptosis found in these hearts. CONCLUSIONS Telethonin knockout mice do not reveal defective heart development or heart function under basal conditions, but develop heart failure following biomechanical stress, owing at least in part to apoptosis of cardiomyocytes, an effect that may also play a role in human heart failure.
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Affiliation(s)
- Ralph Knöll
- Imperial College, National Heart & Lung Institute, British Heart Foundation, Centre for Research Excellence, Myocardial Genetics, London, UK.
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15
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Benyamini H, Friedler A. The ASPP interaction network: electrostatic differentiation between pro- and anti-apoptotic proteins. J Mol Recognit 2011; 24:266-74. [PMID: 20623514 DOI: 10.1002/jmr.1048] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The ASPP proteins are apoptosis regulators: ASPP1 and ASPP2 promote, while iASPP inhibits, apoptosis. The mechanism by which these different outcomes are achieved is still unknown. The C-terminal ankyrin repeats and SH3 domain (ANK-SH3) mediate the interactions of the ASPP proteins with major apoptosis regulators such as p53, Bcl-2, and NFκB. The structure of the complex between ASPP2(ANK-SH3) and the core domain of p53 (p53CD) was previously determined. We have recently characterized the individual interactions of ASPP2(ANK-SH3) with Bcl-2 and NFκB, as well as a regulatory intramolecular interaction with the proline rich domain of ASPP2. Here we compared the ASPP interactions at two levels: ASPP2(ANK-SH3) with different proteins, and different ASPP family members with each protein partner. We found that the binding sites of ASPP2 to p53CD, Bcl-2, and NFκB are different, yet lie on the same face of ASPP2(ANK-SH3) . The intramolecular binding site to the proline rich domain overlaps the three intermolecular binding sites. To reveal the basis of functional diversity in the ASPP family, we compared their protein-binding domains. A subset of surface-exposed residues differentiates ASPP1 and ASPP2 from iASPP: ASPP1/2 are more negatively charged in specific residues that contact positively charged residues of p53CD, Bcl-2, and NFκB. We also found a gain of positive charge at the non-protein binding face of ASPP1/2, suggesting a role in electrostatic direction towards the negatively charged protein binding face. The electrostatic differences in binding interfaces between the ASPP proteins may be one of the causes for their different function.
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Affiliation(s)
- Hadar Benyamini
- The Institute of Chemistry, The Hebrew University of Jerusalem, Safra Campus, Givat Ram, Jerusalem 91904, Israel
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16
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Chen J, Xie F, Zhang L, Jiang WG. iASPP is over-expressed in human non-small cell lung cancer and regulates the proliferation of lung cancer cells through a p53 associated pathway. BMC Cancer 2010; 10:694. [PMID: 21192816 PMCID: PMC3022889 DOI: 10.1186/1471-2407-10-694] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 12/30/2010] [Indexed: 11/12/2022] Open
Abstract
Background iASPP is a key inhibitor of tumour suppressor p53 and is found to be up-regulated in certain malignant conditions. The present study investigated the expression of iASPP in clinical lung cancer, a leading cancer type in the world, and the biological impact of this molecule on lung cancer cells. Methods iASPP protein levels in lung cancer tissues were evaluated using an immunohistochemical method. In vitro, iASPP gene expression was suppressed with a lentvirus-mediated shRNA method and the biological impact after knocking down iASSP on lung cancer cell lines was investigated in connection with the p53 expression status. Results We showed here that the expression of iASPP was significantly higher in lung cancer tissues compared with the adjacent normal tissues. iASPP shRNA treatment resulted in a down-regulation of iASPP in lung cancer cells. There was a subsequent reduction of cell proliferation of the two lung tumour cell lines A459 and 95D both of which had wild-type p53 expression. In contrast, reduction of iASPP in H1229 cells, a cell with little p53 expression, had no impact on its growth rate. Conclusions iASPP regulates the proliferation and motility of lung cancer cells. This effect is intimately associated with the p53 pathway. Together with the pattern of the over-expression in clinical lung cancers, it is concluded that iASPP plays an pivotal role in the progression of lung cancer and is a potential target for lung cancer therapy.
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Affiliation(s)
- Jinfeng Chen
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Thoracic Surgery, Peking University School of Oncology and Beijing Cancer Hospital & Institute Beijing, 100142 PR China
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Fernandez-Fernandez MR, Sot B. The relevance of protein-protein interactions for p53 function: the CPE contribution. Protein Eng Des Sel 2010; 24:41-51. [PMID: 20952436 DOI: 10.1093/protein/gzq074] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The relevance of p53 as a tumour suppressor is evident from the fact that more than 50% of the human cancers hold mutations in the gene coding for p53, and of the remaining cancers a considerable number have alterations in the p53 pathway. From its discovery 30 years ago, the importance of p53 as an essential transcription factor for tumour suppression has become clear. More recently, new and seemingly diverse roles of p53 have been discovered. It soon became clear that protein-protein interactions play an important role in the regulation of the p53 function at different levels. Here we review the contribution by Prof. Fersht and his group towards understanding the basis and functional relevance of p53 protein-protein interactions, and the important role that protein science, biophysics and structural biology have played in the science produced in the Centre for Protein Engineering over the years.
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Liu HS, Hsu PY, Lai MD, Chang HY, Ho CL, Cheng HL, Chen HT, Lin YJ, Wu TJ, Tzai TS, Chow NH. An unusual function of RON receptor tyrosine kinase as a transcriptional regulator in cooperation with EGFR in human cancer cells. Carcinogenesis 2010; 31:1456-64. [PMID: 20498137 DOI: 10.1093/carcin/bgq100] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Homodimerization of RON (MST1R), a receptor tyrosine kinase, usually occurs in cells stimulated by a ligand and leads to the downstream activation of signaling pathways. Here we report that bladder cancer cells, in response to physiological stress, use an alternative mechanism for signaling activation. Time-course studies indicated that RON migrated directly from the membrane to the nucleus of bladder cancer cells in response to serum starvation. Biochemical and genetic studies implied that this nuclear internalization was complexed with epidermal growth factor receptor (EGFR) and required the docking of importins. In vivo analysis confirmed that nuclear RON was present in 38.4% (28/73) of primary bladder tumors. Chromatin immunoprecipitation (ChIP) on microarray analysis further revealed that this internalized complex bound to at least 134 target genes known to participate in three stress-responsive networks: p53, stress-activated protein kinase/c-jun N-terminal kinase and phosphatidylinositol 3-kinase/Akt. These findings suggest that RON, in a complex with EGFR, acts as a transcriptional regulator in response to acute disturbances (e.g. serum starvation) imposed on cancer cells. In an attempt to re-establish homeostasis, these cells bypass regular mechanisms required by ligand stimulation and trigger the RON-directed transcriptional response, which confers a survival advantage.
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Affiliation(s)
- Hsiao-Sheng Liu
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan
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19
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Abstract
The tumor suppressor protein p53 is a transcription factor that plays a key role in the prevention of cancer development. In response to oncogenic or other stresses, the p53 protein is activated and regulates the expression of a variety of target genes, resulting in cell cycle arrest, senescence, or apoptosis. Mutation of the p53 gene is the most common genetic alteration in human cancer, affecting more than 50% of human tumors. Most of these mutations inactivate the DNA-binding domain of the protein. In this chapter, we describe the structure of the wild-type p53 protein and present structural and functional data that provide the molecular basis for understanding the effects of common cancer mutations. Further, we assess novel therapeutic strategies that aim to rescue the function of p53 cancer mutants.
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Affiliation(s)
- Andreas C Joerger
- MRC Centre for Protein Engineering, Cambridge CB2 2QH, United Kingdom
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20
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Abstract
The tumor suppressor p53 is in equilibrium at cellular concentrations between dimers and tetramers. Oncogenic mutant p53 (mut) exerts a dominant-negative effect on co-expression of p53 wild-type (wt) and mut alleles in cancer cells. It is believed that wt and mut form hetero-tetramers of attenuated activity, via their tetramerization domains. Using electrospray mass spectrometry on isotopically labeled samples, we measured directly the composition and rates of formation of p53 complexes in the presence and absence of response element DNA. The dissociation of tetramers was unexpectedly very slow (t(1/2) = 40 min) at 37 degrees C, matched by slow association of dimers, which is approximately four times longer than the half-life of spontaneous denaturation of wt p53. On mixing wt tetramers with the oncogenic contact mutant R273H of low DNA affinity, we observed the same slow formation of only wt(4), wt(2)mut(2), and mut(4), in the ratio 1:2:1, on a cellular time scale. On mixing wt and mut with response element DNAs P21 and BAX, we observed only the complexes wt(4)xDNA, wt(2)mut(2)xDNA, and mut(4)xDNA, with relative dissociation constants 1:4:71 and 1:13:85, respectively, accounting for the dominant-negative effect by weakened affinity. p53 dimers assemble rapidly to tetramers on binding to response element DNA, initiated by the p53 DNA binding domains. The slow oligomerization of free p53, competing with spontaneous denaturation, has implications for the possible regulation of p53 by binding proteins and DNA that affect tetramerization kinetics as well as equilibria.
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21
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Tidow H, Andreeva A, Rutherford TJ, Fersht AR. Solution structure of the U11-48K CHHC zinc-finger domain that specifically binds the 5' splice site of U12-type introns. Structure 2009; 17:294-302. [PMID: 19217400 DOI: 10.1016/j.str.2008.11.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Revised: 11/24/2008] [Accepted: 11/26/2008] [Indexed: 10/21/2022]
Abstract
The formation of stable 18S U11/U12 di-snRNPs before their association with the pre-mRNA is a characteristic feature of the minor spliceosome. During the spliceosomal assembly, the 18S snRNP binds cooperatively to the introns' 5' splice and branch point site. The molecular basis for this recognition is still unknown. Here, we report the solution structure of the U11-48K CHHC Zn finger, a domain unique to the minor spliceosome. The CHHC Zn-finger structure revealed an unexpected similarity to the TFIIIA domains, with distinct features originating from the type and separation of the zinc-coordinating residues. We show that this domain specifically binds the 5' splice site sequence of U12-type introns when base paired to U11 snRNA in vitro and hence may contribute to the U12 intron recognition. We propose a model in which the U11-48K Zn finger stabilizes U11-5' splice site base pairing and thus plays an important role during the minor spliceosome assembly.
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Affiliation(s)
- Henning Tidow
- MRC Centre for Protein Engineering, Hills Road, Cambridge CB20QH, United Kingdom.
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22
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Liu H, Wang M, Diao S, Rao Q, Zhang X, Xing H, Wang J. siRNA-mediated down-regulation of iASPP promotes apoptosis induced by etoposide and daunorubicin in leukemia cells expressing wild-type p53. Leuk Res 2009; 33:1243-8. [PMID: 19299014 DOI: 10.1016/j.leukres.2009.02.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Revised: 02/11/2009] [Accepted: 02/14/2009] [Indexed: 11/25/2022]
Abstract
Oncoprotein inhibitory member of the ASPP family (iASPP) is a key inhibitor of tumor suppressor p53. Our previous study revealed that the expression of iASPP in acute leukemia (AL) patients was higher than that of normal control which implied that iASPP might play an important role in the pathogenesis and/or disease progression of AL. In this study, the iASPP expression was blocked by RNA interference (RNAi) in two leukemic cell lines, Nalm6 and K562, to explore the effects of iASPP on leukemia cells. The results indicated that down-regulation of endogenous iASPP increased p53-dependent apoptosis of leukemia cells. Thus, iASPP could be a molecular target in leukemia therapy.
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Affiliation(s)
- Hang Liu
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Tianjin 300020, China
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23
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Ahn J, Byeon IJL, Byeon CH, Gronenborn AM. Insight into the structural basis of pro- and antiapoptotic p53 modulation by ASPP proteins. J Biol Chem 2009; 284:13812-13822. [PMID: 19246451 DOI: 10.1074/jbc.m808821200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
p53-dependent apoptosis is modulated by the ASPP family of proteins (apoptosis-stimulating proteins of p53; also called ankyrin repeat-, Src homology 3 domain-, and Pro-rich region-containing proteins). Its three known members, ASPP1, ASPP2, and iASPP, were previously found to interact with p53, influencing the apoptotic response of cells without affecting p53-induced cell cycle arrest. More specifically, the bona fide tumor suppressors, ASPP1 and ASPP2, bind to the core domain of p53 and stimulate transcription of apoptotic genes, whereas oncogenic iASPP also binds to the p53 core domain but inhibits p53-dependent apoptosis. Although the general interaction regions are known, details of the interfaces for each p53-ASPP complex have not been evaluated. We undertook a comprehensive biophysical characterization of ASPP-p53 complex formation and mapped the binding interfaces by NMR. We found that the interaction interface on p53 for the proapoptotic protein ASPP2 is distinct from that for the antiapoptotic iASPP. ASPP2 primarily binds to the core domain of p53, whereas iASPP predominantly interacts with a linker region adjacent to the core domain. Our detailed structural analyses of the ASPP-p53 interactions provide insight into the structural basis of the differential behavior of pro- and antiapoptotic ASPP family members.
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Affiliation(s)
- Jinwoo Ahn
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
| | - In-Ja L Byeon
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
| | - Chang-Hyeock Byeon
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
| | - Angela M Gronenborn
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260.
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Abstract
The tumor suppressor protein p53 induces or represses the expression of a variety of target genes involved in cell cycle control, senescence, and apoptosis in response to oncogenic or other cellular stress signals. It exerts its function as guardian of the genome through an intricate interplay of independently folded and intrinsically disordered functional domains. In this review, we provide insights into the structural complexity of p53, the molecular mechanisms of its inactivation in cancer, and therapeutic strategies for the pharmacological rescue of p53 function in tumors. p53 emerges as a paradigm for a more general understanding of the structural organization of modular proteins and the effects of disease-causing mutations.
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Affiliation(s)
- Andreas C Joerger
- Medical Research Council Centre for Protein Engineering, Cambridge, United Kingdom.
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25
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Patel S, George R, Autore F, Fraternali F, Ladbury JE, Nikolova PV. Molecular interactions of ASPP1 and ASPP2 with the p53 protein family and the apoptotic promoters PUMA and Bax. Nucleic Acids Res 2008; 36:5139-51. [PMID: 18676979 PMCID: PMC2532732 DOI: 10.1093/nar/gkn490] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The apoptosis stimulating p53 proteins, ASPP1 and ASPP2, are the first two common activators of the p53 protein family that selectively enable the latter to regulate specific apoptotic target genes, which facilitates yes yet unknown mechanisms for discrimination between cell cycle arrest and apoptosis. To better understand the interplay between ASPP- and p53-family of proteins we investigated the molecular interactions between them using biochemical methods and structure-based homology modelling. The data demonstrate that: (i) the binding of ASPP1 and ASPP2 to p53, p63 and p73 is direct; (ii) the C-termini of ASPP1 and ASPP2 interact with the DNA-binding domains of p53 protein family with dissociation constants, Kd, in the lower micro-molar range; (iii) the stoichiometry of binding is 1:1; (iv) the DNA-binding domains of p53 family members are sufficient for these protein–protein interactions; (v) EMSA titrations revealed that while tri-complex formation between ASPPs, p53 family of proteins and PUMA/Bax is mutually exclusive, ASPP2 (but not ASPP1) formed a complex with PUMA (but not Bax) and displaced p53 and p73. The structure-based homology modelling revealed subtle differences between ASPP2 and ASPP1 and together with the experimental data provide novel mechanistic insights.
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Affiliation(s)
- Seema Patel
- Department of Biochemistry and Pharmaceutical Science Division, School of Biomedical and Health Sciences, King's College London, Franklin-Wilkins Building, 150 Stamford St., London SE1 9NH, UK
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Abstract
Background The tumour suppressor protein p53 protein has a core domain that binds DNA and is the site for most oncogenic mutations. This domain is quite unstable compared to its homologs p63 and p73. Two key residues in the core domain of p53 (Tyr236, Thr253), have been mutated in-silico, to their equivalent residues in p63 (Phe238 and Ile255) and p73 (Phe238 and Ile255), with subsequent increase in stability of p53. Computational studies have been performed to examine the basis of instability in p53. Results Molecular dynamics simulations suggest that mutations in p53 lead to increased conformational sampling of the phase space which stabilizes the system entropically. In contrast, reverse mutations, where p63 and p73 were mutated by replacing the Phe238 and Ile255 by Tyr and Thr respectively (as in p53), showed reduced conformational sampling although the change for p63 was much smaller than that for p73. Barriers to the rotation of sidechains containing aromatic rings at the core of the proteins were reduced several-fold when p53 was mutated; in contrast they increased when p73 was mutated and decreased by a small amount in p63. The rate of ring flipping of a Tyrosine residue at the boundary of two domains can be correlated with the change in stability, with implications for possible pathways of entry of agents that induce unfolding. Conclusion A double mutation at the core of the DNA binding domain of p53 leads to enhanced stability by increasing the softness of the protein. A change from a highly directional polar interaction of the core residues Tyr236 and Thr253 to a non-directional apolar interaction between Phe and Ile respectively may enable the system to adapt more easily and thus increase its robustness to structural perturbations, giving it increased stability. This leads to enhanced conformational sampling which in turn is associated with an increased "softness" of the protein core. However the system seems to become more rigid at the periphery. The success of this methodology in reproducing the experimental trends in the stability of p53 suggests that it has the potential to complement structural studies for rapidly estimating changes in stability upon mutations and could be an additional tool in the design of specific classes of proteins.
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Insights into the structure and protein-protein interactions of the pro-apoptotic protein ASPP2. Biochem Soc Trans 2008; 35:966-9. [PMID: 17956256 DOI: 10.1042/bst0350966] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
ASPP (apoptosis-stimulating protein of p53) 2 is a pro-apoptotic protein that stimulates the p53-mediated apoptotic response. Here, we provide an overview of the structure and protein-protein interactions of ASPP2. The C-terminus of ASPP2 contains Ank (ankyrin) repeats and an SH3 domain (Src homology 3 domain). The Ank-SH3 domains mediate interactions between ASPP2 and numerous proteins involved in apoptosis such as p53 and Bcl-2. The proline-rich domain of ASPP2 is unfolded in its native state, but was not shown to mediate intermolecular interactions. Instead, it makes an intramolecular domain-domain interaction with the Ank-SH3 C-terminal domains of ASPP2. This intramolecular interaction between the unstructured proline-rich domain and the structured Ank-SH3 domains in ASPP2, which is possible due to the unfolded nature of the proline-rich domain, is proposed to have an important role in regulating the intermolecular interactions of ASPP2 with its partner proteins.
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28
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Robinson RA, Lu X, Jones EY, Siebold C. Biochemical and Structural Studies of ASPP Proteins Reveal Differential Binding to p53, p63, and p73. Structure 2008; 16:259-68. [DOI: 10.1016/j.str.2007.11.012] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 11/08/2007] [Accepted: 11/09/2007] [Indexed: 01/03/2023]
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29
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Okhrimenko O, Jelesarov I. A survey of the year 2006 literature on applications of isothermal titration calorimetry. J Mol Recognit 2008; 21:1-19. [DOI: 10.1002/jmr.859] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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30
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Abstract
p53 mutations are found in 50% of human cancers. Molecular epidemiology has shown strong correlations between the spectrum of p53 mutations and exposure to exogenous carcinogens. This spectrum is influenced quantitatively and qualitatively by various upstream genetic filters that modulate carcinogen activation, detoxification, and/or DNA repair. In this review, we will discuss how other factors such as tissue specificity, SNP of genes associated with the p53 pathway, other genetic alterations, or p53 mutant heterogeneity can act as a second set of downstream filters that also have a profound impact on the spectrum of p53 mutations.
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Affiliation(s)
- Thierry Soussi
- Université P.M. Curie, 4 place Jussieu, 75005 Paris, France.
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31
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Tidow H, Melero R, Mylonas E, Freund SMV, Grossmann JG, Carazo JM, Svergun DI, Valle M, Fersht AR. Quaternary structures of tumor suppressor p53 and a specific p53 DNA complex. Proc Natl Acad Sci U S A 2007; 104:12324-9. [PMID: 17620598 PMCID: PMC1941468 DOI: 10.1073/pnas.0705069104] [Citation(s) in RCA: 161] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The homotetrameric tumor suppressor p53 consists of folded core and tetramerization domains, linked and flanked by intrinsically disordered segments that impede structure analysis by x-ray crystallography and NMR. Here, we solved the quaternary structure of human p53 in solution by a combination of small-angle x-ray scattering, which defined its shape, and NMR, which identified the core domain interfaces and showed that the folded domains had the same structure in the intact protein as in fragments. We combined the solution data with electron microscopy on immobilized samples that provided medium resolution 3D maps. Ab initio and rigid body modeling of scattering data revealed an elongated cross-shaped structure with a pair of loosely coupled core domain dimers at the ends, which are accessible for binding to DNA and partner proteins. The core domains in that open conformation closed around a specific DNA response element to form a compact complex whose structure was independently determined by electron microscopy. The structure of the DNA complex is consistent with that of the complex of four separate core domains and response element fragments solved by x-ray crystallography and contacts identified by NMR. Electron microscopy on the conformationally mobile, unbound p53 selected a minor compact conformation, which resembled the closed conformation, from the ensemble of predominantly open conformations. A multipronged structural approach could be generally useful for the structural characterization of the rapidly growing number of multidomain proteins with intrinsically disordered regions.
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Affiliation(s)
- Henning Tidow
- *Medical Research Council Centre for Protein Engineering, Hills Road, Cambridge CB2 0QH, United Kingdom
| | - Roberto Melero
- Centro Nacional de Biotecnología, Darwin 3, Cantoblanco 28049 Madrid, Spain
| | - Efstratios Mylonas
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, 22603 Hamburg, Germany
| | - Stefan M. V. Freund
- *Medical Research Council Centre for Protein Engineering, Hills Road, Cambridge CB2 0QH, United Kingdom
| | - J. Guenter Grossmann
- Molecular Biophysics Group, Council for the Central Laboratory of the Research Councils (CCLRC) Daresbury Laboratory, Warrington, Cheshire WA4 4AD, United Kingdom
| | - José María Carazo
- Centro Nacional de Biotecnología, Darwin 3, Cantoblanco 28049 Madrid, Spain
| | - Dmitri I. Svergun
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, 22603 Hamburg, Germany
- Institute of Crystallography, Russian Academy of Sciences, Leninsky pr. 59, 117333 Moscow, Russia; and
- To whom correspondence may be addressed. E-mail: , , or
| | - Mikel Valle
- Centro Nacional de Biotecnología, Darwin 3, Cantoblanco 28049 Madrid, Spain
- **CIC-bioGUNE, Parque Tecnológico de Bizkaia, 48160 Derio, Spain
- To whom correspondence may be addressed. E-mail: , , or
| | - Alan R. Fersht
- *Medical Research Council Centre for Protein Engineering, Hills Road, Cambridge CB2 0QH, United Kingdom
- To whom correspondence may be addressed. E-mail: , , or
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32
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Tidow H, Andreeva A, Rutherford TJ, Fersht AR. Solution structure of ASPP2 N-terminal domain (N-ASPP2) reveals a ubiquitin-like fold. J Mol Biol 2007; 371:948-58. [PMID: 17594908 DOI: 10.1016/j.jmb.2007.05.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2007] [Revised: 05/07/2007] [Accepted: 05/07/2007] [Indexed: 11/30/2022]
Abstract
Proteins of the ASPP family bind to p53 and regulate p53-mediated apoptosis. Two family members, ASPP1 and ASPP2, have pro-apoptotic functions while iASPP shows anti-apoptotic responses. However, both the mechanism of enhancement/repression of apoptosis and the molecular basis for their different responses remain unknown. To address the role of the N-termini of pro-apoptotic ASPP proteins, we solved the solution structure of N-ASPP2 (1-83) by NMR spectroscopy. The structure of this domain reveals a beta-Grasp ubiquitin-like fold. Our findings suggest a possible role for the N-termini of ASPP proteins in binding to other proteins in the apoptotic response network and thus mediating their selective pro-apoptotic function.
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Affiliation(s)
- Henning Tidow
- MRC Centre for Protein Engineering, Hills Road, Cambridge CB2 0QH, UK
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33
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Abstract
The tumor suppressor protein p53 is inactivated by mutation in about half of all human cancers. Most mutations are located in the DNA-binding domain of the protein. It is, therefore, important to understand the structure of p53 and how it responds to mutation, so as to predict the phenotypic response and cancer prognosis. In this review, we present recent structural and systematic functional data that elucidate the molecular basis of how p53 is inactivated by different types of cancer mutation. Intriguingly, common cancer mutants exhibit a variety of distinct local structural changes, while the overall structural scaffold is largely preserved. The diverse structural and energetic response to mutation determines: (i) the folding state of a particular mutant under physiological conditions; (ii) its affinity for the various p53 target DNA sequences; and (iii) its protein-protein interactions both within the p53 tetramer and with a multitude of regulatory proteins. Further, the structural details of individual mutants provide the basis for the design of specific and generic drugs for cancer therapy purposes. In combination with studies on second-site suppressor mutations, it appears that some mutants are ideal rescue candidates, whereas for others simple pharmacological rescue by small molecule drugs may not be successful.
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Affiliation(s)
- A C Joerger
- Centre for Protein Engineering, Medical Research Council Centre, Cambridge, UK.
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34
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Abstract
The strongest and undisputed fact about p53 is the high frequency of p53 alterations in human cancer and that mutant p53 proteins constitute a complex family of several hundred proteins with heterogeneous properties. Beyond these observations, the p53 pathway and its regulation in a normal cell is like a desert trail, always moving with the wind of novel findings. The field is full of black boxes that are often ignored for sake of simplicity or because they do not fit with the current dominant view. Mutant p53 protein accumulation in tumours is the best example of a preconceived idea, as there is no experimental evidence to explain this observation. In this review, we will discuss several questions concerning the activity or selection of p53 mutations. The central domain of the p53 protein targeted by 80% of p53 mutations is associated with the DNA-binding activity of the p53 protein, but it is also the binding site for several proteins that play a key role in p53 regulation such as ASPP proteins or BclxL. The role of impaired DNA binding and/or protein interactions in tumour development has not been fully elucidated. Similarly, novel animal models carrying either missense p53 mutations or inducible p53 have provided abundant observations, some of which could challenge our view on p53 function as a tumour suppressor gene. Finally, the possible clinical applications of p53 will be discussed.
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Affiliation(s)
- T Soussi
- Department of Life Sciences, Université Pierre et Marie Curie-Paris, Paris, France.
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35
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Zhang X, Diao S, Rao Q, Xing H, Liu H, Liao X, Wang M, Wang J. Identification of a Novel Isoform of iASPP and its Interaction with p53. J Mol Biol 2007; 368:1162-71. [PMID: 17391696 DOI: 10.1016/j.jmb.2007.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Revised: 02/28/2007] [Accepted: 03/01/2007] [Indexed: 01/07/2023]
Abstract
iASPP is an inhibitory member of ASPP (apoptosis stimulating protein of p53, or Ankyrin repeats, SH3 domain and proline-rich region contain Protein) family. As reported previously, it at least includes two isoforms, one is iASPP/RAI (351 amino acids, aa) and the other is iASPP (828 aa).Here, we identified a novel open reading frame of human iASPP, which encodes a 407 aa protein and highly matches with the C terminus of iASPP (828 aa, CAI60219). Hereafter, iASPP (407 aa) will be referred to as iASPP-SV (iASPP splice variant). In further study, we found that iASPP-SV is a nuclear protein, and is capable of binding to p53 in vivo. Moreover, overexpression of iASPP-SV can inhibit the transcriptional activity of p53 on the promoters of both Bax and p21.
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Affiliation(s)
- Xinwei Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Tianjin 300020, China
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Joerger AC, Ang HC, Fersht AR. Structural basis for understanding oncogenic p53 mutations and designing rescue drugs. Proc Natl Acad Sci U S A 2006; 103:15056-61. [PMID: 17015838 PMCID: PMC1635156 DOI: 10.1073/pnas.0607286103] [Citation(s) in RCA: 225] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The DNA-binding domain of the tumor suppressor p53 is inactivated by mutation in approximately 50% of human cancers. We have solved high-resolution crystal structures of several oncogenic mutants to investigate the structural basis of inactivation and provide information for designing drugs that may rescue inactivated mutants. We found a variety of structural consequences upon mutation: (i) the removal of an essential contact with DNA, (ii) creation of large, water-accessible crevices or hydrophobic internal cavities with no other structural changes but with a large loss of thermodynamic stability, (iii) distortion of the DNA-binding surface, and (iv) alterations to surfaces not directly involved in DNA binding but involved in domain-domain interactions on binding as a tetramer. These findings explain differences in functional properties and associated phenotypes (e.g., temperature sensitivity). Some mutants have the potential of being rescued by a generic stabilizing drug. In addition, a mutation-induced crevice is a potential target site for a mutant-selective stabilizing drug.
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Affiliation(s)
- Andreas C. Joerger
- Cambridge University Chemical Laboratory and Cambridge Centre for Protein Engineering, Medical Research Council Centre, Hills Road, Cambridge CB2 2QH, United Kingdom
| | - Hwee Ching Ang
- Cambridge University Chemical Laboratory and Cambridge Centre for Protein Engineering, Medical Research Council Centre, Hills Road, Cambridge CB2 2QH, United Kingdom
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