1
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Nalawansha DA, Mangano K, den Besten W, Potts PR. TAC-tics for Leveraging Proximity Biology in Drug Discovery. Chembiochem 2024; 25:e202300712. [PMID: 38015747 DOI: 10.1002/cbic.202300712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 11/30/2023]
Abstract
Chemically induced proximity (CIP) refers to co-opting naturally occurring biological pathways using synthetic molecules to recruit neosubstrates that are not normally encountered or to enhance the affinity of naturally occurring interactions. Leveraging proximity biology through CIPs has become a rapidly evolving field and has garnered considerable interest in basic research and drug discovery. PROteolysis TArgeting Chimera (PROTAC) is a well-established CIP modality that induces the proximity between a target protein and an E3 ubiquitin ligase, causing target protein degradation via the ubiquitin-proteasome system. Inspired by PROTACs, several other induced proximity modalities have emerged to modulate both proteins and RNA over recent years. In this review, we summarize the critical advances and opportunities in the field, focusing on protein degraders, RNA degraders and non-degrader modalities such as post-translational modification (PTM) and protein-protein interaction (PPI) modulators. We envision that these emerging proximity-based drug modalities will be valuable resources for both biological research and therapeutic discovery in the future.
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Affiliation(s)
| | - Kyle Mangano
- Induced Proximity Platform, Amgen Research, Thousand Oaks, CA 91320, USA
| | - Willem den Besten
- Induced Proximity Platform, Amgen Research, Thousand Oaks, CA 91320, USA
| | - Patrick Ryan Potts
- Induced Proximity Platform, Amgen Research, Thousand Oaks, CA 91320, USA
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2
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Rui H, Ashton KS, Min J, Wang C, Potts PR. Protein-protein interfaces in molecular glue-induced ternary complexes: classification, characterization, and prediction. RSC Chem Biol 2023; 4:192-215. [PMID: 36908699 PMCID: PMC9994104 DOI: 10.1039/d2cb00207h] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 01/02/2023] [Indexed: 01/04/2023] Open
Abstract
Molecular glues are a class of small molecules that stabilize the interactions between proteins. Naturally occurring molecular glues are present in many areas of biology where they serve as central regulators of signaling pathways. Importantly, several clinical compounds act as molecular glue degraders that stabilize interactions between E3 ubiquitin ligases and target proteins, leading to their degradation. Molecular glues hold promise as a new generation of therapeutic agents, including those molecular glue degraders that can redirect the protein degradation machinery in a precise way. However, rational discovery of molecular glues is difficult in part due to the lack of understanding of the protein-protein interactions they stabilize. In this review, we summarize the structures of known molecular glue-induced ternary complexes and the interface properties. Detailed analysis shows different mechanisms of ternary structure formation. Additionally, we also review computational approaches for predicting protein-protein interfaces and highlight the promises and challenges. This information will ultimately help inform future approaches for rational molecular glue discovery.
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Affiliation(s)
- Huan Rui
- Center for Research Acceleration by Digital Innovation, Amgen Research Thousand Oaks CA 91320 USA
| | - Kate S Ashton
- Medicinal Chemistry, Amgen Research Thousand Oaks CA 91320 USA
| | - Jaeki Min
- Induced Proximity Platform, Amgen Research Thousand Oaks CA 91320 USA
| | - Connie Wang
- Digital, Technology & Innovation, Amgen Thousand Oaks CA 91320 USA
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3
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Abstract
The discovery of new small molecule ligands for E3 ligases will enable the creation of novel proteolysis targeting chimeras (PROTACs) and molecular glues to tackle traditionally undruggable proteins. Diversifying both the chemical matter for each E3 ligase and the type of ligases will be important to fully capture the potential of these targeted protein degradation modalities. A key step in this process is to establish an integrated screening platform for the rapid identification and optimization of small molecule ligands for E3 ligases. Here, we provide a method to evaluate E3 ligase ligands using AlphaScreen technology. AlphaScreen allows for the evaluation of a wide array of molecular interactions and is utilized extensively in small molecule screening campaigns. This bead-based proximity technology offers facile development for interactions across a wide range of affinities and can be adapted to interrogate E3 ligase-degron interactions. In this protocol, we demonstrate the development of AlphaScreen for E3 ligase ligand competition assays toward the discovery of new ligands for E3 ligases.
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Affiliation(s)
- Robert G Guenette
- Induced Proximity Platform, Amgen Research, Thousand Oaks, CA, United States
| | - Patrick Ryan Potts
- Induced Proximity Platform, Amgen Research, Thousand Oaks, CA, United States.
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4
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Abstract
Targeted protein degradation (TPD) strategies have revolutionized how scientists tackle challenging protein targets deemed undruggable with traditional small molecule inhibitors. Many promising campaigns to inhibit proteins have failed due to factors surrounding inhibition selectivity and targeting of compounds to specific tissues and cell types. One of the major improvements that PROTAC (proteolysis targeting chimera) and molecular glue technology can exert is highly selective control of target inhibition. Multiple studies have shown that PROTACs can gain selectivity for their protein targets beyond that of their parent ligands via optimization of linker length and stabilization of ternary complexes. Due to the bifunctional nature of PROTACs, the tissue selective nature of E3 ligases can be exploited to uncover novel targeting mechanisms. In this review, we provide critical analysis of the recent progress towards making selective PROTAC molecules and new PROTAC technologies that will continue to push the boundaries of achieving selectivity. These efforts have wide implications in the future of treating disease as they will broaden the possible targets that can be addressed by small molecules, like undruggable proteins or broadly active targets that would benefit from degradation in specific tissue types.
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Affiliation(s)
| | - Seung Wook Yang
- Induced Proximity Platform, Amgen, Thousand Oaks, CA 91320, USA.
| | - Jaeki Min
- Induced Proximity Platform, Amgen, Thousand Oaks, CA 91320, USA.
| | - Baikang Pei
- Genome Analysis Unit, Amgen, Thousand Oaks, CA 91320, USA
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5
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Min J, Mayasundari A, Keramatnia F, Jonchere B, Yang SW, Jarusiewicz J, Actis M, Das S, Young B, Slavish J, Yang L, Li Y, Fu X, Garrett SH, Yun M, Li Z, Nithianantham S, Chai S, Chen T, Shelat A, Lee RE, Nishiguchi G, White SW, Roussel MF, Potts PR, Fischer M, Rankovic Z. Phenyl‐Glutarimides: Alternative Cereblon Binders for the Design of PROTACs. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jaeki Min
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Anand Mayasundari
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Fatemeh Keramatnia
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Barbara Jonchere
- Department of Tumor Cell Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Seung Wook Yang
- Department of Cell & Molecular Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Jamie Jarusiewicz
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Marisa Actis
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Sourav Das
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Brandon Young
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Jake Slavish
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Lei Yang
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Yong Li
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Xiang Fu
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Shalandus H. Garrett
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Mi‐Kyung Yun
- Department of Structural Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Zhenmei Li
- Department of Structural Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Stanley Nithianantham
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Sergio Chai
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Anang Shelat
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Richard E. Lee
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Gisele Nishiguchi
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Stephen W. White
- Department of Structural Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Martine F. Roussel
- Department of Tumor Cell Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Patrick Ryan Potts
- Department of Cell & Molecular Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Marcus Fischer
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
- Department of Structural Biology St. Jude Children's Research Hospital Memphis TN 38105 USA
| | - Zoran Rankovic
- Department of Chemical Biology and Therapeutics St. Jude Children's Research Hospital Memphis TN 38105 USA
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6
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Min J, Mayasundari A, Keramatnia F, Jonchere B, Yang SW, Jarusiewicz J, Actis M, Das S, Young B, Slavish J, Yang L, Li Y, Fu X, Garrett SH, Yun MK, Li Z, Nithianantham S, Chai S, Chen T, Shelat A, Lee RE, Nishiguchi G, White SW, Roussel MF, Potts PR, Fischer M, Rankovic Z. Phenyl-Glutarimides: Alternative Cereblon Binders for the Design of PROTACs. Angew Chem Int Ed Engl 2021; 60:26663-26670. [PMID: 34614283 PMCID: PMC8648984 DOI: 10.1002/anie.202108848] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Indexed: 12/15/2022]
Abstract
Targeting cereblon (CRBN) is currently one of the most frequently reported proteolysis-targeting chimera (PROTAC) approaches, owing to favorable drug-like properties of CRBN ligands, immunomodulatory imide drugs (IMiDs). However, IMiDs are known to be inherently unstable, readily undergoing hydrolysis in body fluids. Here we show that IMiDs and IMiD-based PROTACs rapidly hydrolyze in commonly utilized cell media, which significantly affects their cell efficacy. We designed novel CRBN binders, phenyl glutarimide (PG) analogues, and showed that they retained affinity for CRBN with high ligand efficiency (LE >0.48) and displayed improved chemical stability. Our efforts led to the discovery of PG PROTAC 4 c (SJ995973), a uniquely potent degrader of bromodomain and extra-terminal (BET) proteins that inhibited the viability of human acute myeloid leukemia MV4-11 cells at low picomolar concentrations (IC50 =3 pM; BRD4 DC50 =0.87 nM). These findings strongly support the utility of PG derivatives in the design of CRBN-directed PROTACs.
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Affiliation(s)
- Jaeki Min
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Anand Mayasundari
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Fatemeh Keramatnia
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Barbara Jonchere
- Department of Tumor Cell Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Seung Wook Yang
- Department of Cell & Molecular Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Jamie Jarusiewicz
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Marisa Actis
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Sourav Das
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Brandon Young
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Jake Slavish
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Lei Yang
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Yong Li
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Xiang Fu
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Shalandus H. Garrett
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Mi-Kyung Yun
- Department of Structural Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Zhenmei Li
- Department of Structural Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Stanley Nithianantham
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Sergio Chai
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Anang Shelat
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Richard E. Lee
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Gisele Nishiguchi
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Stephen W. White
- Department of Structural Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Martine F. Roussel
- Department of Tumor Cell Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Patrick Ryan Potts
- Department of Cell & Molecular Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Marcus Fischer
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
- Department of Structural Biology, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
| | - Zoran Rankovic
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105, United States
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7
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Koirala S, Klein J, Zheng Y, Glenn NO, Eisemann T, Fon Tacer K, Miller DJ, Kulak O, Lu M, Finkelstein DB, Neale G, Tillman H, Vogel P, Strand DW, Lum L, Brautigam CA, Pascal JM, Clements WK, Potts PR. Tissue-Specific Regulation of the Wnt/β-Catenin Pathway by PAGE4 Inhibition of Tankyrase. Cell Rep 2021; 32:107922. [PMID: 32698014 DOI: 10.1016/j.celrep.2020.107922] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/30/2020] [Accepted: 06/26/2020] [Indexed: 01/10/2023] Open
Abstract
Spatiotemporal control of Wnt/β-catenin signaling is critical for organism development and homeostasis. The poly-(ADP)-ribose polymerase Tankyrase (TNKS1) promotes Wnt/β-catenin signaling through PARylation-mediated degradation of AXIN1, a component of the β-catenin destruction complex. Although Wnt/β-catenin is a niche-restricted signaling program, tissue-specific factors that regulate TNKS1 are not known. Here, we report prostate-associated gene 4 (PAGE4) as a tissue-specific TNKS1 inhibitor that robustly represses canonical Wnt/β-catenin signaling in human cells, zebrafish, and mice. Structural and biochemical studies reveal that PAGE4 acts as an optimal substrate decoy that potently hijacks substrate binding sites on TNKS1 to prevent AXIN1 PARylation and degradation. Consistently, transgenic expression of PAGE4 in mice phenocopies TNKS1 knockout. Physiologically, PAGE4 is selectively expressed in stromal prostate fibroblasts and functions to establish a proper Wnt/β-catenin signaling niche through suppression of autocrine signaling. Our findings reveal a non-canonical mechanism for TNKS1 inhibition that functions to establish tissue-specific control of the Wnt/β-catenin pathway.
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Affiliation(s)
- Sajjan Koirala
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Jonathon Klein
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Yumei Zheng
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Nicole O Glenn
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA; Department of Biology, Belmont University, Nashville, TN, USA
| | - Travis Eisemann
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Klementina Fon Tacer
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Darcie J Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ozlem Kulak
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Meifen Lu
- Veterinary Pathology Core, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - David B Finkelstein
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Geoffrey Neale
- Hartwell Center, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Heather Tillman
- Veterinary Pathology Core, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Peter Vogel
- Veterinary Pathology Core, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Douglas W Strand
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lawrence Lum
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Pfizer, La Jolla, CA, USA
| | - Chad A Brautigam
- Departments of Biophysics and Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - John M Pascal
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Wilson K Clements
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA.
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8
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Florke Gee RR, Chen H, Lee AK, Daly CA, Wilander BA, Fon Tacer K, Potts PR. Emerging roles of the MAGE protein family in stress response pathways. J Biol Chem 2020; 295:16121-16155. [PMID: 32921631 PMCID: PMC7681028 DOI: 10.1074/jbc.rev120.008029] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 09/08/2020] [Indexed: 12/21/2022] Open
Abstract
The melanoma antigen (MAGE) proteins all contain a MAGE homology domain. MAGE genes are conserved in all eukaryotes and have expanded from a single gene in lower eukaryotes to ∼40 genes in humans and mice. Whereas some MAGEs are ubiquitously expressed in tissues, others are expressed in only germ cells with aberrant reactivation in multiple cancers. Much of the initial research on MAGEs focused on exploiting their antigenicity and restricted expression pattern to target them with cancer immunotherapy. Beyond their potential clinical application and role in tumorigenesis, recent studies have shown that MAGE proteins regulate diverse cellular and developmental pathways, implicating them in many diseases besides cancer, including lung, renal, and neurodevelopmental disorders. At the molecular level, many MAGEs bind to E3 RING ubiquitin ligases and, thus, regulate their substrate specificity, ligase activity, and subcellular localization. On a broader scale, the MAGE genes likely expanded in eutherian mammals to protect the germline from environmental stress and aid in stress adaptation, and this stress tolerance may explain why many cancers aberrantly express MAGEs Here, we present an updated, comprehensive review on the MAGE family that highlights general characteristics, emphasizes recent comparative studies in mice, and describes the diverse functions exerted by individual MAGEs.
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Affiliation(s)
- Rebecca R Florke Gee
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, Tennessee, USA; Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Helen Chen
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Anna K Lee
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Christina A Daly
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, Tennessee, USA; Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Benjamin A Wilander
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, Tennessee, USA; Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Klementina Fon Tacer
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, Tennessee, USA; School of Veterinary Medicine, Texas Tech University, Amarillo, Texas, USA.
| | - Patrick Ryan Potts
- Cell and Molecular Biology Department, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
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9
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Yang SW, Huang X, Lin W, Min J, Miller DJ, Mayasundari A, Rodrigues P, Griffith EC, Gee CT, Li L, Li W, Lee RE, Rankovic Z, Chen T, Potts PR. Structural basis for substrate recognition and chemical inhibition of oncogenic MAGE ubiquitin ligases. Nat Commun 2020; 11:4931. [PMID: 33004795 PMCID: PMC7529893 DOI: 10.1038/s41467-020-18708-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 09/08/2020] [Indexed: 12/17/2022] Open
Abstract
Testis-restricted melanoma antigen (MAGE) proteins are frequently hijacked in cancer and play a critical role in tumorigenesis. MAGEs assemble with E3 ubiquitin ligases and function as substrate adaptors that direct the ubiquitination of novel targets, including key tumor suppressors. However, how MAGEs recognize their targets is unknown and has impeded the development of MAGE-directed therapeutics. Here, we report the structural basis for substrate recognition by MAGE ubiquitin ligases. Biochemical analysis of the degron motif recognized by MAGE-A11 and the crystal structure of MAGE-A11 bound to the PCF11 substrate uncovered a conserved substrate binding cleft (SBC) in MAGEs. Mutation of the SBC disrupted substrate recognition by MAGEs and blocked MAGE-A11 oncogenic activity. A chemical screen for inhibitors of MAGE-A11:substrate interaction identified 4-Aminoquinolines as potent inhibitors of MAGE-A11 that show selective cytotoxicity. These findings provide important insights into the large family of MAGE ubiquitin ligases and identify approaches for developing cancer-specific therapeutics.
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Affiliation(s)
- Seung Wook Yang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Xin Huang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Wenwei Lin
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Jaeki Min
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Darcie J Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Anand Mayasundari
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Patrick Rodrigues
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Elizabeth C Griffith
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Clifford T Gee
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Lei Li
- Division of Computational Biomedicine, Department of Biological Chemistry, School of Medicine, University of California Irvine, 5270 California Ave, Irvine, CA, 92617, USA
| | - Wei Li
- Division of Computational Biomedicine, Department of Biological Chemistry, School of Medicine, University of California Irvine, 5270 California Ave, Irvine, CA, 92617, USA
| | - Richard E Lee
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Zoran Rankovic
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA.
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10
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Chen H, Victor AK, Klein J, Tacer KF, Tai DJ, de Esch C, Nuttle A, Temirov J, Burnett LC, Rosenbaum M, Zhang Y, Ding L, Moresco JJ, Diedrich JK, Yates JR, Tillman HS, Leibel RL, Talkowski ME, Billadeau DD, Reiter LT, Potts PR. Loss of MAGEL2 in Prader-Willi syndrome leads to decreased secretory granule and neuropeptide production. JCI Insight 2020; 5:138576. [PMID: 32879135 PMCID: PMC7526459 DOI: 10.1172/jci.insight.138576] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/22/2020] [Indexed: 12/17/2022] Open
Abstract
Prader-Willi syndrome (PWS) is a developmental disorder caused by loss of maternally imprinted genes on 15q11-q13, including melanoma antigen gene family member L2 (MAGEL2). The clinical phenotypes of PWS suggest impaired hypothalamic neuroendocrine function; however, the exact cellular defects are unknown. Here, we report deficits in secretory granule (SG) abundance and bioactive neuropeptide production upon loss of MAGEL2 in humans and mice. Unbiased proteomic analysis of Magel2pΔ/m+ mice revealed a reduction in components of SG in the hypothalamus that was confirmed in 2 PWS patient-derived neuronal cell models. Mechanistically, we show that proper endosomal trafficking by the MAGEL2-regulated WASH complex is required to prevent aberrant lysosomal degradation of SG proteins and reduction of mature SG abundance. Importantly, loss of MAGEL2 in mice, NGN2-induced neurons, and human patients led to reduced neuropeptide production. Thus, MAGEL2 plays an important role in hypothalamic neuroendocrine function, and cellular defects in this pathway may contribute to PWS disease etiology. Moreover, these findings suggest unanticipated approaches for therapeutic intervention.
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Affiliation(s)
- Helen Chen
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - A Kaitlyn Victor
- Department of Neurology, Department of Pediatrics, and Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Jonathon Klein
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Klementina Fon Tacer
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Derek Jc Tai
- Center for Genomic Medicine, Department of Neurology, Department of Pathology, and Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts, USA.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
| | - Celine de Esch
- Center for Genomic Medicine, Department of Neurology, Department of Pathology, and Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts, USA.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
| | - Alexander Nuttle
- Center for Genomic Medicine, Department of Neurology, Department of Pathology, and Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts, USA.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
| | - Jamshid Temirov
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Lisa C Burnett
- Levo Therapeutics, Inc., Skokie, Illinois, USA.,Division of Molecular Genetics, Department of Pediatrics, and Naomi Berrie Diabetes Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, New York, USA
| | - Michael Rosenbaum
- Division of Molecular Genetics, Department of Pediatrics, and Naomi Berrie Diabetes Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, New York, USA
| | - Yiying Zhang
- Division of Molecular Genetics, Department of Pediatrics, and Naomi Berrie Diabetes Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, New York, USA
| | - Li Ding
- Division of Oncology Research and Schulze Center for Novel Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | - James J Moresco
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Jolene K Diedrich
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - John R Yates
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Heather S Tillman
- Veterinary Pathology Core, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Rudolph L Leibel
- Division of Molecular Genetics, Department of Pediatrics, and Naomi Berrie Diabetes Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, New York, USA
| | - Michael E Talkowski
- Center for Genomic Medicine, Department of Neurology, Department of Pathology, and Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts, USA.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
| | - Daniel D Billadeau
- Division of Oncology Research and Schulze Center for Novel Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | - Lawrence T Reiter
- Department of Neurology, Department of Pediatrics, and Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
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11
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Abstract
SIRT1 is a NAD+ -dependent deacetylase that controls key metabolic and signaling pathways, including inactivating the p53 tumor suppressor. However, the mechanisms controlling SIRT1 enzymatic activity in the context of cancer are unclear. Here, we show that the previously undescribed CSAG2 protein is a direct activator of SIRT1. CSAG2 is normally restricted to expression in the male germline but is frequently re-activated in cancers. CSAG2 is necessary for cancer cell proliferation and promotes tumorigenesis in vivo. Biochemical studies revealed that CSAG2 directly binds to and stimulates SIRT1 activity toward multiple substrates. Importantly, CSAG2 enhances SIRT1-mediated deacetylation of p53, inhibits p53 transcriptional activity, and improves cell survival in response to genotoxic stress. Mechanistically, CSAG2 binds SIRT1 catalytic domain and promotes activity independent of altering substrate affinity. Together, our results identify a previously undescribed mechanism for SIRT1 activation in cancer cells and highlight unanticipated approaches to therapeutically modulate SIRT1.
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Affiliation(s)
- Xu Yang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
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12
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Lee AK, Klein J, Fon Tacer K, Lord T, Oatley MJ, Oatley JM, Porter SN, Pruett-Miller SM, Tikhonova EB, Karamyshev AL, Wang YD, Yang P, Korff A, Kim HJ, Taylor JP, Potts PR. Translational Repression of G3BP in Cancer and Germ Cells Suppresses Stress Granules and Enhances Stress Tolerance. Mol Cell 2020; 79:645-659.e9. [PMID: 32692974 DOI: 10.1016/j.molcel.2020.06.037] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/10/2020] [Accepted: 06/29/2020] [Indexed: 02/08/2023]
Abstract
Stress granules (SGs) are membrane-less ribonucleoprotein condensates that form in response to various stress stimuli via phase separation. SGs act as a protective mechanism to cope with acute stress, but persistent SGs have cytotoxic effects that are associated with several age-related diseases. Here, we demonstrate that the testis-specific protein, MAGE-B2, increases cellular stress tolerance by suppressing SG formation through translational inhibition of the key SG nucleator G3BP. MAGE-B2 reduces G3BP protein levels below the critical concentration for phase separation and suppresses SG initiation. Knockout of the MAGE-B2 mouse ortholog or overexpression of G3BP1 confers hypersensitivity of the male germline to heat stress in vivo. Thus, MAGE-B2 provides cytoprotection to maintain mammalian spermatogenesis, a highly thermosensitive process that must be preserved throughout reproductive life. These results demonstrate a mechanism that allows for tissue-specific resistance against stress and could aid in the development of male fertility therapies.
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Affiliation(s)
- Anna K Lee
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Jonathon Klein
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Klementina Fon Tacer
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Tessa Lord
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Melissa J Oatley
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Jon M Oatley
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Shaina N Porter
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Shondra M Pruett-Miller
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Yong-Dong Wang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Peiguo Yang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ane Korff
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Hong Joo Kim
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - J Paul Taylor
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA.
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13
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Yang SW, Li L, Connelly JP, Porter SN, Kodali K, Gan H, Park JM, Tacer KF, Tillman H, Peng J, Pruett-Miller SM, Li W, Potts PR. A Cancer-Specific Ubiquitin Ligase Drives mRNA Alternative Polyadenylation by Ubiquitinating the mRNA 3' End Processing Complex. Mol Cell 2020; 77:1206-1221.e7. [PMID: 31980388 DOI: 10.1016/j.molcel.2019.12.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/02/2019] [Accepted: 12/23/2019] [Indexed: 12/14/2022]
Abstract
Alternative polyadenylation (APA) contributes to transcriptome complexity by generating mRNA isoforms with varying 3' UTR lengths. APA leading to 3' UTR shortening (3' US) is a common feature of most cancer cells; however, the molecular mechanisms are not understood. Here, we describe a widespread mechanism promoting 3' US in cancer through ubiquitination of the mRNA 3' end processing complex protein, PCF11, by the cancer-specific MAGE-A11-HUWE1 ubiquitin ligase. MAGE-A11 is normally expressed only in the male germline but is frequently re-activated in cancers. MAGE-A11 is necessary for cancer cell viability and is sufficient to drive tumorigenesis. Screening for targets of MAGE-A11 revealed that it ubiquitinates PCF11, resulting in loss of CFIm25 from the mRNA 3' end processing complex. This leads to APA of many transcripts affecting core oncogenic and tumor suppressors, including cyclin D2 and PTEN. These findings provide insights into the molecular mechanisms driving APA in cancer and suggest therapeutic strategies.
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Affiliation(s)
- Seung Wook Yang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Lei Li
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, CA 92697, USA; Division of Biostatistics, Dan L. Duncan Cancer Center and Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jon P Connelly
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shaina N Porter
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Kiran Kodali
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Haiyun Gan
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jung Mi Park
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Klementina Fon Tacer
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Heather Tillman
- Veterinary Pathology Core, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Junmin Peng
- Departments of Structural Biology and Developmental Neurobiology, Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shondra M Pruett-Miller
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Wei Li
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, CA 92697, USA; Division of Biostatistics, Dan L. Duncan Cancer Center and Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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14
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Ravichandran R, Kodali K, Peng J, Potts PR. Regulation of MAGE-A3/6 by the CRL4-DCAF12 ubiquitin ligase and nutrient availability. EMBO Rep 2019; 20:e47352. [PMID: 31267705 PMCID: PMC6607007 DOI: 10.15252/embr.201847352] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 04/08/2019] [Accepted: 04/18/2019] [Indexed: 12/12/2022] Open
Abstract
Melanoma antigen genes (MAGEs) are emerging as important oncogenic drivers that are normally restricted to expression in male germ cells but are aberrantly expressed in cancers and promote tumorigenesis. Mechanistically, MAGEs function as substrate specifying subunits of E3 ubiquitin ligases. Thus, the activation of germline-specific genes in cancer can drive metabolic and signaling pathways through altered ubiquitination to promote tumorigenesis. However, the mechanisms regulating MAGE expression and activity are unclear. Here, we describe how the MAGE-A3/6 proteins that function as repressors of autophagy are downregulated in response to nutrient deprivation. Short-term cellular starvation promotes rapid MAGE-A3/6 degradation in a proteasome-dependent manner. Proteomic analysis reveals that degradation of MAGE-A3/6 is controlled by the CRL4-DCAF12 E3 ubiquitin ligase. Importantly, the degradation of MAGE-A3/6 by CRL4-DCAF12 is required for starvation-induced autophagy. These findings suggest that oncogenic MAGEs can be dynamically controlled in response to stress to allow cellular adaptation, autophagy regulation, and tumor growth and that CRL4-DCAF12 activity is responsive to nutrient status.
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Affiliation(s)
- Ramya Ravichandran
- Department of Cell and Molecular BiologySt. Jude Children's Research HospitalMemphisTNUSA
| | - Kiran Kodali
- Departments of Structural Biology and Developmental NeurobiologyCenter for Proteomics and MetabolomicsSt. Jude Children's Research HospitalMemphisTNUSA
| | - Junmin Peng
- Departments of Structural Biology and Developmental NeurobiologyCenter for Proteomics and MetabolomicsSt. Jude Children's Research HospitalMemphisTNUSA
| | - Patrick Ryan Potts
- Department of Cell and Molecular BiologySt. Jude Children's Research HospitalMemphisTNUSA
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15
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Fon Tacer K, Montoya MC, Oatley MJ, Lord T, Oatley JM, Klein J, Ravichandran R, Tillman H, Kim M, Connelly JP, Pruett-Miller SM, Bookout AL, Binshtock E, Kamiński MM, Potts PR. MAGE cancer-testis antigens protect the mammalian germline under environmental stress. Sci Adv 2019; 5:eaav4832. [PMID: 31149633 PMCID: PMC6541465 DOI: 10.1126/sciadv.aav4832] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 04/17/2019] [Indexed: 05/17/2023]
Abstract
Ensuring robust gamete production even in the face of environmental stress is of utmost importance for species survival, especially in mammals that have low reproductive rates. Here, we describe a family of genes called melanoma antigens (MAGEs) that evolved in eutherian mammals and are normally restricted to expression in the testis (http://MAGE.stjude.org) but are often aberrantly activated in cancer. Depletion of Mage-a genes disrupts spermatogonial stem cell maintenance and impairs repopulation efficiency in vivo. Exposure of Mage-a knockout mice to genotoxic stress or long-term starvation that mimics famine in nature causes defects in spermatogenesis, decreased testis weights, diminished sperm production, and reduced fertility. Last, human MAGE-As are activated in many cancers where they promote fuel switching and growth of cells. These results suggest that mammalian-specific MAGE genes have evolved to protect the male germline against environmental stress, ensure reproductive success under non-optimal conditions, and are hijacked by cancer cells.
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Affiliation(s)
- Klementina Fon Tacer
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Marhiah C. Montoya
- Clinical & Translational Science Institute, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
- Departments of Pediatrics, Microbiology and Immunology, Carver College of Medicine, University of Iowa, IA, USA
| | - Melissa J. Oatley
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Tessa Lord
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Jon M. Oatley
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Jonathon Klein
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Ramya Ravichandran
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Heather Tillman
- Veterinary Pathology Core, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - MinSoo Kim
- Departments of Internal Medicine and Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jon P. Connelly
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | | | - Angie L. Bookout
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Emily Binshtock
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Marcin M. Kamiński
- Department of Immunology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Patrick Ryan Potts
- Department of Cell & Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
- Corresponding author.
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16
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Trošt N, Peña-Llopis S, Koirala S, Stojan J, Potts PR, Fon Tacer K, Martinez ED. Correction: γKlotho is a novel marker and cell survival factor in a subset of triple negative breast cancers. Oncotarget 2019; 10:916. [PMID: 30783519 PMCID: PMC6368237 DOI: 10.18632/oncotarget.26649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Nuša Trošt
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Samuel Peña-Llopis
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Sajjan Koirala
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jurij Stojan
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Patrick Ryan Potts
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Klementina Fon Tacer
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Elisabeth D Martinez
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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17
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Collins RR, Tacer KF, Rakheja D, Potts PR. Abstract 4880: MAGE gene family expression in pediatric medulloblastoma: frequency and possible therapeutic target. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-4880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: The melanoma antigen gene family (MAGE) is a group of related genes that were first discovered in malignant melanoma. Among the approximately 40 MAGE genes in the human genome, two thirds are classified as Type I (MAGE-A, MAGE-B, and MAGE-C), referred to also as cancer testis antigens (CTAs), proteins that are restricted to testis but often aberrantly expressed in many adult cancers. Despite their common expression in adult cancers and their oncogenic potential, little is known about their expression and role in pediatric cancers. To determine the frequency of MAGE expression in pediatric medulloblastoma, we measured expression levels of Type I MAGEs in patient tumors. In addition, we examined how MAGE expression in medulloblastoma cells affects their growth and oncogenic potential.
Methods: We searched the Children’s Health pathology database for pediatric medulloblastoma between 2008 - 2015 and were able to recover an adequate amount of RNA from formalin-fixed paraffin-embedded tissue samples of 34 patients. The RNA was converted to cDNA using reverse transcriptase, and the relative expression of 23 Type I MAGE genes was measured by qRT-PCR.
To determine if MAGE expression is critical for medulloblastoma cell survival we knocked down several MAGEs using siRNAs in two MAGE-expressing medulloblastoma cell lines (D283 and DAOY) and evaluated the effect by cell viability (Alamar Blue and Cell titer Glo), apoptosis assays (Annexin V), and colony formation in soft agar.
Results: In 34 medulloblastoma patient samples we found that 10 (29.4%) expressed at least one MAGE gene, and one case had high levels of expression of 10 of the 23 Type I MAGEs. MAGE expression was associated with the non-WNT/SHH (G3/G4) molecular subgroup of tumors in our study. There was no correlation between MAGE expression and histologic subtype. Furthermore, using MAGE-A/-B2 positive medulloblastoma cell lines, we showed that siRNA knock down of multiple MAGE-As and -B2 decreased cell viability by 15 - 80%, increased apoptosis (-B2), and decreased growth of cells in soft agar.
Conclusion: Type I MAGE genes are expressed in 30% of pediatric medulloblastoma in our study. In MAGE positive medulloblastoma cells, MAGE genes are important for cell survival and clonogenic growth. The decreased cell survival after MAGE knockdown appears to be related, at least in part, to increased apoptosis. Our results indicate that targeting of MAGEs in medulloblastoma may be a potential therapeutic option.
Citation Format: Rebecca R. Collins, Klementina Fon Tacer, Dinesh Rakheja, Patrick Ryan Potts. MAGE gene family expression in pediatric medulloblastoma: frequency and possible therapeutic target [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4880. doi:10.1158/1538-7445.AM2017-4880
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Affiliation(s)
- Rebecca R. Collins
- 1University of Texas Southwestern Medical Center and Children's Health, Dallas, TX
| | | | - Dinesh Rakheja
- 1University of Texas Southwestern Medical Center and Children's Health, Dallas, TX
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18
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Tomimatsu N, Mukherjee B, Harris JL, Boffo FL, Hardebeck MC, Potts PR, Khanna KK, Burma S. DNA-damage-induced degradation of EXO1 exonuclease limits DNA end resection to ensure accurate DNA repair. J Biol Chem 2017; 292:10779-10790. [PMID: 28515316 DOI: 10.1074/jbc.m116.772475] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 05/11/2017] [Indexed: 12/22/2022] Open
Abstract
End resection of DNA double-strand breaks (DSBs) to generate 3'-single-stranded DNA facilitates DSB repair via error-free homologous recombination (HR) while stymieing repair by the error-prone non-homologous end joining (NHEJ) pathway. Activation of DNA end resection involves phosphorylation of the 5' to 3' exonuclease EXO1 by the phosphoinositide 3-kinase-like kinases ATM (ataxia telangiectasia-mutated) and ATR (ATM and Rad3-related) and by the cyclin-dependent kinases 1 and 2. After activation, EXO1 must also be restrained to prevent over-resection that is known to hamper optimal HR and trigger global genomic instability. However, mechanisms by which EXO1 is restrained are still unclear. Here, we report that EXO1 is rapidly degraded by the ubiquitin-proteasome system soon after DSB induction in human cells. ATR inhibition attenuated DNA-damage-induced EXO1 degradation, indicating that ATR-mediated phosphorylation of EXO1 targets it for degradation. In accord with these results, EXO1 became resistant to degradation when its SQ motifs required for ATR-mediated phosphorylation were mutated. We show that upon the induction of DNA damage, EXO1 is ubiquitinated by a member of the Skp1-Cullin1-F-box (SCF) family of ubiquitin ligases in a phosphorylation-dependent manner. Importantly, expression of degradation-resistant EXO1 resulted in hyper-resection, which attenuated both NHEJ and HR and severely compromised DSB repair resulting in chromosomal instability. These findings indicate that the coupling of EXO1 activation with its eventual degradation is a timing mechanism that limits the extent of DNA end resection for accurate DNA repair.
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Affiliation(s)
- Nozomi Tomimatsu
- From the Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Bipasha Mukherjee
- From the Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Janelle Louise Harris
- Signal Transduction Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland 4006, Australia
| | - Francesca Ludovica Boffo
- Department of Molecular Medicine and Medical Biotechnology, Università Federico II, Napoli 80131, Italy, and
| | - Molly Catherine Hardebeck
- From the Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Kum Kum Khanna
- Signal Transduction Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland 4006, Australia
| | - Sandeep Burma
- From the Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390,
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19
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Jin X, Pan Y, Wang L, Zhang L, Ravichandran R, Potts PR, Jiang J, Wu H, Huang H. MAGE-TRIM28 complex promotes the Warburg effect and hepatocellular carcinoma progression by targeting FBP1 for degradation. Oncogenesis 2017; 6:e312. [PMID: 28394358 PMCID: PMC5520498 DOI: 10.1038/oncsis.2017.21] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 01/25/2017] [Accepted: 02/27/2017] [Indexed: 01/16/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is one of the leading cause of cancer death in the world. Fructose-1,6-biphosphatase (FBP1), a rate-limiting enzyme in gluconeogenesis, has been identified recently as a tumor suppressor in HCC and other cancer types. In this study, we demonstrated that the tripartite motif-containing protein 28 (TRIM28) binds directly to and promotes FBP1 for ubiquitination and degradation. MAGE-A3 and MAGE-C2, which are known to be overexpressed in HCC, can enhance TRIM28-dependent degradation of FBP1 by forming ubiquitin ligase complexes with TRIM28. We further showed that expression of TRIM28 increased glucose consumption and lactate production by promoting FBP1 degradation in HCC cells and that FBP1 is a key mediator of TRIM28-induced HCC growth in culture and in mice. Moreover, we demonstrated that FBP1 and TRIM28 protein levels inversely correlated in HCC patient specimens. Finally, we showed that the proteasome inhibitor bortezomib mitigated the Warburg effect by inhibiting FBP1 degradation in HCC. Collectively, our findings not only identify oncogenic MAGE-TRIM28 complex-mediated proteasome degradation of FBP1 as a key mechanism underlying downregulation of FBP1 proteins in HCC, but also reveal that MAGE-TRIM28-regulated reprogramming of cancer cell metabolism and HCC tumorigenesis is mediated, at least in part, through FBP1 degradation.
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Affiliation(s)
- X Jin
- Department of Digestive Surgical Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Y Pan
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - L Wang
- Department of Medical Informatics and Statistics, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - L Zhang
- Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - R Ravichandran
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - P R Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - J Jiang
- Department of Tumor Biological Treatment, The Third Affiliated Hospital of Soochow University, Changzhou, China
| | - H Wu
- Department of Pancreatic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - H Huang
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN, USA.,Department of Urology, Mayo Clinic College of Medicine, Rochester, MN, USA.,Mayo Clinic Cancer Center, Mayo Clinic College of Medicine, Rochester, MN, USA
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20
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Lee AK, Potts PR. A Comprehensive Guide to the MAGE Family of Ubiquitin Ligases. J Mol Biol 2017; 429:1114-1142. [PMID: 28300603 DOI: 10.1016/j.jmb.2017.03.005] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 03/07/2017] [Accepted: 03/07/2017] [Indexed: 12/28/2022]
Abstract
Melanoma antigen (MAGE) genes are conserved in all eukaryotes and encode for proteins sharing a common MAGE homology domain. Although only a single MAGE gene exists in lower eukaryotes, the MAGE family rapidly expanded in eutherians and consists of more than 50 highly conserved genes in humans. A subset of MAGEs initially garnered interest as cancer biomarkers and immunotherapeutic targets due to their antigenic properties and unique expression pattern that is primary restricted to germ cells and aberrantly reactivated in various cancers. However, further investigation revealed that MAGEs not only drive tumorigenesis but also regulate pathways essential for diverse cellular and developmental processes. Therefore, MAGEs are implicated in a broad range of diseases including neurodevelopmental, renal, and lung disorders, and cancer. Recent biochemical and biophysical studies indicate that MAGEs assemble with E3 RING ubiquitin ligases to form MAGE-RING ligases (MRLs) and act as regulators of ubiquitination by modulating ligase activity, substrate specification, and subcellular localization. Here, we present a comprehensive guide to MAGEs highlighting the molecular mechanisms of MRLs and their physiological roles in germ cell and neural development, oncogenic functions in cancer, and potential as therapeutic targets in disease.
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Affiliation(s)
- Anna K Lee
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
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21
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Abstract
In this issue of Molecular Cell, Nguyen et al. (2016) show that p300/CBP-mediated acetylation of glutamine synthetase (GS) triggers recognition by the CRL4(CRBN) E3 ubiquitin ligase, resulting in its ubiquitylation and degradation in response to high glutamine concentrations.
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Affiliation(s)
- Sajjan Koirala
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
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22
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Abstract
Autophagy is commonly altered in cancer and has a complicated, but important role in regulation of tumor growth. Autophagy is often tumor suppressive in the early stages of cancer development, but contributes to the late stages of tumor growth. Because of this, putative oncogenes that modulate autophagy signaling are especially interesting. Here we discuss our recent work detailing the function of the MAGEA-TRIM28 ubiquitin ligase as an oncogene product that targets PRKAA1/AMPKα1 for ubiquitination and proteasome-mediated degradation. Degradation of AMPK, a master cellular energy sensor and regulator, by MAGEA-TRIM28 results in significantly reduced autophagy and changes in cellular metabolism, including upregulation of MTOR signaling. Overall, expression of MAGEA3 (or MAGEA6) and degradation of AMPK is sufficient to induce transformation of normal cells and promote multiple hallmarks of cancer.
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Affiliation(s)
- Carlos T Pineda
- a Departments of Physiology, Pharmacology, and Biochemistry; UT Southwestern ; Dallas , TX , USA
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23
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Hao YH, Fountain MD, Fon Tacer K, Xia F, Bi W, Kang SHL, Patel A, Rosenfeld JA, Le Caignec C, Isidor B, Krantz ID, Noon SE, Pfotenhauer JP, Morgan TM, Moran R, Pedersen RC, Saenz MS, Schaaf CP, Potts PR. USP7 Acts as a Molecular Rheostat to Promote WASH-Dependent Endosomal Protein Recycling and Is Mutated in a Human Neurodevelopmental Disorder. Mol Cell 2015; 59:956-69. [PMID: 26365382 DOI: 10.1016/j.molcel.2015.07.033] [Citation(s) in RCA: 139] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 07/07/2015] [Accepted: 07/30/2015] [Indexed: 12/01/2022]
Abstract
Endosomal protein recycling is a fundamental cellular process important for cellular homeostasis, signaling, and fate determination that is implicated in several diseases. WASH is an actin-nucleating protein essential for this process, and its activity is controlled through K63-linked ubiquitination by the MAGE-L2-TRIM27 ubiquitin ligase. Here, we show that the USP7 deubiquitinating enzyme is an integral component of the MAGE-L2-TRIM27 ligase and is essential for WASH-mediated endosomal actin assembly and protein recycling. Mechanistically, USP7 acts as a molecular rheostat to precisely fine-tune endosomal F-actin levels by counteracting TRIM27 auto-ubiquitination/degradation and preventing overactivation of WASH through directly deubiquitinating it. Importantly, we identify de novo heterozygous loss-of-function mutations of USP7 in individuals with a neurodevelopmental disorder, featuring intellectual disability and autism spectrum disorder. These results provide unanticipated insights into endosomal trafficking, illuminate the cooperativity between an ubiquitin ligase and a deubiquitinating enzyme, and establish a role for USP7 in human neurodevelopmental disease.
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Affiliation(s)
- Yi-Heng Hao
- Departments of Physiology, Pharmacology, and Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Michael D Fountain
- Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Klementina Fon Tacer
- Departments of Physiology, Pharmacology, and Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Fan Xia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Weimin Bi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sung-Hae L Kang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ankita Patel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | | | | | - Bertrand Isidor
- Service de Génétique Médicale, CHU de Nantes, Nantes 44093, France
| | - Ian D Krantz
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah E Noon
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Jean P Pfotenhauer
- Division of Medical Genetics and Genomic Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Thomas M Morgan
- Division of Medical Genetics and Genomic Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Rocio Moran
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Robert C Pedersen
- Department of Pediatrics, Tripler Army Medical Center, Honolulu, HI 96859, USA
| | - Margarita S Saenz
- Clinical Genetics and Metabolism, Children's Hospital Colorado, Aurora, CO 80045, USA
| | - Christian P Schaaf
- Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA.
| | - Patrick Ryan Potts
- Departments of Physiology, Pharmacology, and Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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24
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Abstract
The Melanoma Antigen Gene (MAGE) protein family is a large, highly conserved group of proteins that share a common MAGE homology domain. Intriguingly, many MAGE proteins are restricted in expression to reproductive tissues, but are aberrantly expressed in a wide variety of cancer types. Originally discovered as antigens on tumor cells and developed as cancer immunotherapy targets, recent literature suggests a more prominent role for MAGEs in driving tumorigenesis. This review will highlight recent developments into the function of MAGEs as oncogenes, their mechanisms of action in regulation of ubiquitin ligases, and outstanding questions in the field.
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Affiliation(s)
- Jenny L Weon
- Departments of Physiology, Pharmacology, and Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390, United States
| | - Patrick Ryan Potts
- Departments of Physiology, Pharmacology, and Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390, United States.
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25
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Pineda CT, Ramanathan S, Fon Tacer K, Weon JL, Potts MB, Ou YH, White MA, Potts PR. Degradation of AMPK by a cancer-specific ubiquitin ligase. Cell 2015; 160:715-728. [PMID: 25679763 DOI: 10.1016/j.cell.2015.01.034] [Citation(s) in RCA: 255] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/03/2014] [Accepted: 01/15/2015] [Indexed: 12/19/2022]
Abstract
AMP-activated protein kinase (AMPK) is a master sensor and regulator of cellular energy status. Upon metabolic stress, AMPK suppresses anabolic and promotes catabolic processes to regain energy homeostasis. Cancer cells can occasionally suppress the growth-restrictive AMPK pathway by mutation of an upstream regulatory kinase. Here, we describe a widespread mechanism to suppress AMPK through its ubiquitination and degradation by the cancer-specific MAGE-A3/6-TRIM28 ubiquitin ligase. MAGE-A3 and MAGE-A6 are highly similar proteins normally expressed only in the male germline but frequently re-activated in human cancers. MAGE-A3/6 are necessary for cancer cell viability and are sufficient to drive tumorigenic properties of non-cancerous cells. Screening for targets of MAGE-A3/6-TRIM28 revealed that it ubiquitinates and degrades AMPKα1. This leads to inhibition of autophagy, activation of mTOR signaling, and hypersensitization to AMPK agonists, such as metformin. These findings elucidate a germline mechanism commonly hijacked in cancer to suppress AMPK.
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Affiliation(s)
- Carlos T Pineda
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Saumya Ramanathan
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Klementina Fon Tacer
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jenny L Weon
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Malia B Potts
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yi-Hung Ou
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Michael A White
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Patrick Ryan Potts
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Departments of Pharmacology and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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26
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Hao YH, Doyle JM, Ramanathan S, Gomez TS, Jia D, Xu M, Chen ZJ, Billadeau DD, Rosen MK, Potts PR. Regulation of WASH-dependent actin polymerization and protein trafficking by ubiquitination. Cell 2013; 152:1051-64. [PMID: 23452853 DOI: 10.1016/j.cell.2013.01.051] [Citation(s) in RCA: 177] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 11/29/2012] [Accepted: 01/24/2013] [Indexed: 02/01/2023]
Abstract
Endosomal protein trafficking is an essential cellular process that is deregulated in several diseases and targeted by pathogens. Here, we describe a role for ubiquitination in this process. We find that the E3 RING ubiquitin ligase, MAGE-L2-TRIM27, localizes to endosomes through interactions with the retromer complex. Knockdown of MAGE-L2-TRIM27 or the Ube2O E2 ubiquitin-conjugating enzyme significantly impaired retromer-mediated transport. We further demonstrate that MAGE-L2-TRIM27 ubiquitin ligase activity is required for nucleation of endosomal F-actin by the WASH regulatory complex, a known regulator of retromer-mediated transport. Mechanistic studies showed that MAGE-L2-TRIM27 facilitates K63-linked ubiquitination of WASH K220. Significantly, disruption of WASH ubiquitination impaired endosomal F-actin nucleation and retromer-dependent transport. These findings provide a cellular and molecular function for MAGE-L2-TRIM27 in retrograde transport, including an unappreciated role of K63-linked ubiquitination and identification of an activating signal of the WASH regulatory complex.
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Affiliation(s)
- Yi-Heng Hao
- Department of Physiology, UT Southwestern Dallas, TX 75390, USA
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27
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Wu N, Kong X, Ji Z, Zeng W, Potts PR, Yokomori K, Yu H. Scc1 sumoylation by Mms21 promotes sister chromatid recombination through counteracting Wapl. Genes Dev 2012; 26:1473-85. [PMID: 22751501 DOI: 10.1101/gad.193615.112] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
DNA double-strand breaks (DSBs) fuel cancer-driving chromosome translocations. Two related structural maintenance of chromosomes (Smc) complexes, cohesin and Smc5/6, promote DSB repair through sister chromatid homologous recombination (SCR). Here we show that the Smc5/6 subunit Mms21 sumoylates multiple lysines of the cohesin subunit Scc1. Mms21 promotes cohesin-dependent small ubiquitin-like modifier (SUMO) accumulation at laser-induced DNA damage sites in S/G2 human cells. Cells expressing the nonsumoylatable Scc1 mutant (15KR) maintain sister chromatid cohesion during mitosis but are defective in SCR and sensitive to ionizing radiation (IR). Scc1 15KR is recruited to DNA damage sites. Depletion of Wapl, a negative cohesin regulator, rescues SCR defects of Mms21-deficient or Scc1 15KR-expressing cells. Expression of the acetylation-mimicking Smc3 mutant does not bypass the requirement for Mms21 in SCR. We propose that Scc1 sumoylation by Mms21 promotes SCR by antagonizing Wapl at a step after cohesin loading at DSBs and in a way not solely dependent on Smc3 acetylation.
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Affiliation(s)
- Nan Wu
- Howard Hughes Medical Institute, Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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28
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Wu N, Kong X, Ji Z, Yokomori K, Potts PR, Yu H. Scc1 sumoylation by Mms21 promotes sister chromatid recombination through counteracting Wapl. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.539.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Nan Wu
- Department of PharmacologyUT Southwestern Medical CenterDallasTX
| | - Xiangduo Kong
- Department of Biological ChemistryUniversity of California IrvineIrvineCA
| | - Zhejian Ji
- Department of PharmacologyUT Southwestern Medical CenterDallasTX
| | - Kyoko Yokomori
- Department of Biological ChemistryUniversity of California IrvineIrvineCA
| | - Patrick Ryan Potts
- Department of PhysiologyUniversity of Texas Southwestern Medical CenterDallasTX
| | - Hongtao Yu
- Department of PharmacologyUT Southwestern Medical CenterDallasTX
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29
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Doyle JM, Gao J, Wang J, Yang M, Potts PR. MAGE-RING protein complexes comprise a family of E3 ubiquitin ligases. Mol Cell 2010; 39:963-74. [PMID: 20864041 DOI: 10.1016/j.molcel.2010.08.029] [Citation(s) in RCA: 347] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 05/19/2010] [Accepted: 07/09/2010] [Indexed: 12/25/2022]
Abstract
The melanoma antigen (MAGE) family consists of more than 60 genes, many of which are cancer-testis antigens that are highly expressed in cancer and play a critical role in tumorigenesis. However, the biochemical and cellular functions of this enigmatic family of proteins have remained elusive. Here, we identify really interesting new gene (RING) domain proteins as binding partners for MAGE family proteins. Multiple MAGE family proteins bind E3 RING ubiquitin ligases with specificity. The crystal structure of one of these MAGE-RING complexes, MAGE-G1-NSE1, reveals structural insights into MAGE family proteins and their interaction with E3 RING ubiquitin ligases. Biochemical and cellular assays demonstrate that MAGE proteins enhance the ubiquitin ligase activity of RING domain proteins. For example, MAGE-C2-TRIM28 is shown to target p53 for degradation in a proteasome-dependent manner, consistent with its tumorigenic functions. These findings define a biochemical and cellular function for the MAGE protein family.
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Affiliation(s)
- Jennifer M Doyle
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390-9038, USA
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30
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Abstract
The use of lentiviral vectors extends from the laboratory, where they are used for basic studies in virology and as gene transfer vectors gene delivery, to the clinic, where clinical trials using these vectors for gene therapy are currently underway. Lentiviral vectors are useful for gene transfer because they have a large cloning capacity and a broad tropism. Although procedures for lentiviral vector production have been standardized, simple methods to create higher titer virus during production would have extensive and important applications for both research and clinical use. Here we present a simple and inexpensive method to increase the titer by 3- to 8-fold for both integration-competent lentivirus and integration-deficient lentivirus. This is achieved during standard lentiviral production by the addition of caffeine to a final concentration of 2-4 mM. We find that sodium butyrate, a histone deacetylase inhibitor shown previously to increase viral titer, works only ∼50% as well as caffeine. We also show that the DNA-PKcs (DNA-dependent protein kinase catalytic subunit) inhibitor NU7026 can also increase viral titer, but that the combination of caffeine and NU7026 is not more effective than caffeine alone. We show that the time course of caffeine treatment is important in achieving a higher titer virus, and is most effective when caffeine is present from 17 to 41 hr posttransfection. Last, although caffeine increases lentiviral vector titer, it has the opposite effect on the titer of adeno-associated virus type 2 vector. Together, these results provide a novel, simple, and inexpensive way to significantly increase the titer of lentiviral vectors.
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Affiliation(s)
- Brian L Ellis
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
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31
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Potts PR. Abstract A21: MAGE cancer-testis antigens facilitate the degradation of p53 by E3 RING ubiquitin ligases. Cancer Res 2009. [DOI: 10.1158/0008-5472.fbcr09-a21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cancer testis antigens are aberrantly expressed in cancer cells but absent from normal somatic cells, and as such they constitute excellent targets for cancer immunotherapy. Surprising recent evidence suggests that their aberrant expression in cancer cells is not simply an inert consequence of widespread genomic deregulation, but rather an important functional event promoting the cancer phenotype. However, the mechanism through which these proteins promote cancer remains completely unknown due to the lack of structural or functional characterization. Here we report the structural and functional identity of the MAGE proteins, a large family of cancer testis antigens and ubiquitous proteins of previously unknown function. Through structural prediction, X-ray crystallography, and biochemistry we show that a conserved feature of the MAGE family of proteins is their ability to bind to E3 RING ubiquitin ligases, such TRIM28/KAP1. Surprisingly, MAGE-RING ubiquitin ligases share structural and biochemical similarities to Cullin-RING ubiquitin ligases. Most notably, MAGEs activate the ubiquitin ligase activity of E3 RING ubiquitin ligases. Furthermore, we show that the tumor suppressor p53 is a critical and direct target of MAGE-mediated ubiquitination and degradation in breast cancer. Thus we have identified a novel, cancer-specific regulator of p53 degradation and breast cancer survival and discovered the function of the enigmatic MAGE family of cancer testis antigens. These results underscore the importance of MAGE proteins as therapeutic targets for cancer.
Citation Information: Cancer Res 2009;69(23 Suppl):A21.
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32
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Abstract
Maintaining genomic stability is critical for the prevention of disease. Numerous DNA repair pathways help to maintain genomic stability by correcting potentially lethal or disease-causing lesions to our genomes. Mounting evidence suggests that the post-translational modification sumoylation plays an important regulatory role in several aspects of DNA repair. The E3 SUMO ligase MMS21/NSE2 has gained increasing attention for its function in homologous recombination (HR), an error-free DNA repair pathway that mediates repair of double-strand breaks (DSBs) using the sister chromatid as a repair template. MMS21/NSE2 is part of the SMC5/6 complex, which has been shown to facilitate DSB repair, collapsed replication fork restart, and telomere elongation by HR. Here, I review the function of the SMC5/6 complex and its associated MMS21/NSE2 SUMO ligase activity in homologous recombination.
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Affiliation(s)
- Patrick Ryan Potts
- Department of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9038, United States.
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33
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Potts PR, Yu H. The SMC5/6 complex maintains telomere length in ALT cancer cells through SUMOylation of telomere-binding proteins. Nat Struct Mol Biol 2007; 14:581-90. [PMID: 17589526 DOI: 10.1038/nsmb1259] [Citation(s) in RCA: 277] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Accepted: 05/02/2007] [Indexed: 11/08/2022]
Abstract
Most cancer cells activate telomerase to elongate telomeres and achieve unlimited replicative potential. Some cancer cells cannot activate telomerase and use telomere homologous recombination (HR) to elongate telomeres, a mechanism termed alternative lengthening of telomeres (ALT). A hallmark of ALT cells is the recruitment of telomeres to PML bodies (termed APBs). Here, we show that the SMC5/6 complex localizes to APBs in ALT cells and is required for targeting telomeres to APBs. The MMS21 SUMO ligase of the SMC5/6 complex SUMOylates multiple telomere-binding proteins, including TRF1 and TRF2. Inhibition of TRF1 or TRF2 SUMOylation prevents APB formation. Depletion of SMC5/6 subunits by RNA interference inhibits telomere HR, causing telomere shortening and senescence in ALT cells. Thus, the SMC5/6 complex facilitates telomere HR and elongation in ALT cells by promoting APB formation through SUMOylation of telomere-binding proteins.
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Affiliation(s)
- Patrick Ryan Potts
- Department of Pharmacology, The University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, Texas 75390-9041, USA
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34
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Potts PR, Yu H. The SMC5/6 Complex Maintains Telomere Length in ALT Cancer Cells through Sumoylation of Telomere‐Binding Proteins. FASEB J 2007. [DOI: 10.1096/fasebj.21.5.a655-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Patrick Ryan Potts
- PharmacologyUT Southwestern Medical Center6001 Forest Park RdDallasTX75390‐9041
| | - Hongtao Yu
- PharmacologyUT Southwestern Medical Center6001 Forest Park RdDallasTX75390‐9041
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35
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Potts PR, Porteus MH, Yu H. Human SMC5/6 complex promotes sister chromatid homologous recombination by recruiting the SMC1/3 cohesin complex to double-strand breaks. EMBO J 2006; 25:3377-88. [PMID: 16810316 PMCID: PMC1523187 DOI: 10.1038/sj.emboj.7601218] [Citation(s) in RCA: 200] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Accepted: 06/07/2006] [Indexed: 01/09/2023] Open
Abstract
The structural maintenance of chromosomes (SMC) family of proteins has been implicated in the repair of DNA double-strand breaks (DSBs) by homologous recombination (HR). The SMC1/3 cohesin complex is thought to promote HR by maintaining the close proximity of sister chromatids at DSBs. The SMC5/6 complex is also required for DNA repair, but the mechanism by which it accomplishes this is unclear. Here, we show that RNAi-mediated knockdown of the SMC5/6 complex components in human cells increases the efficiency of gene targeting due to a specific requirement for hSMC5/6 in sister chromatid HR. Knockdown of the hSMC5/6 complex decreases sister chromatid HR, but does not reduce nonhomologous end-joining (NHEJ) or intra-chromatid, homologue, or extrachromosomal HR. The hSMC5/6 complex is itself recruited to nuclease-induced DSBs and is required for the recruitment of cohesin to DSBs. Our results establish a mechanism by which the hSMC5/6 complex promotes DNA repair and suggest a novel strategy to improve the efficiency of gene targeting in mammalian somatic cells.
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Affiliation(s)
- Patrick Ryan Potts
- Department of Pharmacology, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Matthew H Porteus
- Department of Pediatrics, The University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Hongtao Yu
- Department of Pharmacology, The University of Texas Southwestern Medical Center, Dallas, TX, USA
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36
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Abstract
DNA repair is required for the genomic stability and well-being of an organism. In yeasts, a multisubunit complex consisting of SMC5, SMC6, MMS21/NSE2, and other non-SMC proteins is required for DNA repair through homologous recombination. The yeast MMS21 protein is a SUMO ligase. Here we show that the human homolog of MMS21 is also a SUMO ligase. hMMS21 stimulates sumoylation of hSMC6 and the DNA repair protein TRAX. Depletion of hMMS21 by RNA interference (RNAi) sensitizes HeLa cells toward DNA damage-induced apoptosis. Ectopic expression of wild-type hMMS21, but not its ligase-inactive mutant, rescues this hypersensitivity of hMMS21-RNAi cells. ATM/ATR are hyperactivated in hMMS21-RNAi cells upon DNA damage. Consistently, hMMS21-RNAi cells show an increased number of phospho-CHK2 foci. Finally, we show that hMMS21-RNAi cells show a decreased capacity to repair DNA lesions as measured by the comet assay. Our findings suggest that the human SMC5/6 complex and the SUMO ligase activity of hMMS21 are required for the prevention of DNA damage-induced apoptosis by facilitating DNA repair in human cells.
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Affiliation(s)
- Patrick Ryan Potts
- Department of Pharmacology, The University of Texas Southwestern Medical Center, Dallas, 75390-9041, USA
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37
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Wright KM, Linhoff MW, Potts PR, Deshmukh M. Decreased apoptosome activity with neuronal differentiation sets the threshold for strict IAP regulation of apoptosis. ACTA ACUST UNITED AC 2004; 167:303-13. [PMID: 15504912 PMCID: PMC2172554 DOI: 10.1083/jcb.200406073] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Despite the potential of the inhibitor of apoptosis proteins (IAPs) to block cytochrome c-dependent caspase activation, the critical function of IAPs in regulating mammalian apoptosis remains unclear. We report that the ability of endogenous IAPs to effectively regulate caspase activation depends on the differentiation state of the cell. Despite being expressed at equivalent levels, endogenous IAPs afforded no protection against cytochrome c-induced apoptosis in naive pheochromocytoma (PC12) cells, but were remarkably effective in doing so in neuronally differentiated cells. Neuronal differentiation was also accompanied with a marked reduction in Apaf-1, resulting in a significant decrease in apoptosome activity. Importantly, this decrease in Apaf-1 protein was directly linked to the increased ability of IAPs to stringently regulate apoptosis in neuronally differentiated PC12 and primary cells. These data illustrate specifically how the apoptotic pathway acquires increased regulation with cellular differentiation, and are the first to show that IAP function and apoptosome activity are coupled in cells.
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Affiliation(s)
- Kevin M Wright
- Curriculum in Neurobiology, University of North Carolina, Chapel Hill, NC 27599, USA
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Potts PR, Singh S, Knezek M, Thompson CB, Deshmukh M. Critical function of endogenous XIAP in regulating caspase activation during sympathetic neuronal apoptosis. ACTA ACUST UNITED AC 2003; 163:789-99. [PMID: 14623868 PMCID: PMC2173693 DOI: 10.1083/jcb.200307130] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
In sympathetic neurons, unlike most nonneuronal cells, growth factor withdrawal–induced apoptosis requires the development of competence in addition to cytochrome c release to activate caspases. Thus, although most nonneuronal cells die rapidly with cytosolic cytochrome c alone, sympathetic neurons are remarkably resistant unless they develop competence. We have identified endogenous X-linked inhibitor of apoptosis protein (XIAP) as the essential postcytochrome c regulator of caspase activation in these neurons. In contrast to wild-type neurons that are resistant to injection of cytochrome c, XIAP-deficient neurons died rapidly with cytosolic cytochrome c alone. Surprisingly, the release of endogenous Smac was not sufficient to overcome the XIAP resistance in sympathetic neurons. In contrast, the neuronal competence pathway permitted cytochrome c to activate caspases by inducing a marked reduction in XIAP levels in these neurons. Thus, the removal of XIAP inhibition appears both necessary and sufficient for cytochrome c to activate caspases in sympathetic neurons. These data identify a critical function of endogenous XIAP in regulating apoptosis in mammalian cells.
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Affiliation(s)
- Patrick Ryan Potts
- Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599, USA
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