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Yang CY, Lien CI, Tseng YC, Tu YF, Kulczyk AW, Lu YC, Wang YT, Su TW, Hsu LC, Lo YC, Lin SC. Deciphering DED assembly mechanisms in FADD-procaspase-8-cFLIP complexes regulating apoptosis. Nat Commun 2024; 15:3791. [PMID: 38710704 PMCID: PMC11074299 DOI: 10.1038/s41467-024-47990-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 04/17/2024] [Indexed: 05/08/2024] Open
Abstract
Fas-associated protein with death domain (FADD), procaspase-8, and cellular FLICE-inhibitory proteins (cFLIP) assemble through death-effector domains (DEDs), directing death receptor signaling towards cell survival or apoptosis. Understanding their three-dimensional regulatory mechanism has been limited by the absence of atomic coordinates for their ternary DED complex. By employing X-ray crystallography and cryogenic electron microscopy (cryo-EM), we present the atomic coordinates of human FADD-procaspase-8-cFLIP complexes, revealing structural insights into these critical interactions. These structures illustrate how FADD and cFLIP orchestrate the assembly of caspase-8-containing complexes and offer mechanistic explanations for their role in promoting or inhibiting apoptotic and necroptotic signaling. A helical procaspase-8-cFLIP hetero-double layer in the complex appears to promote limited caspase-8 activation for cell survival. Our structure-guided mutagenesis supports the role of the triple-FADD complex in caspase-8 activation and in regulating receptor-interacting protein kinase 1 (RIPK1). These results propose a unified mechanism for DED assembly and procaspase-8 activation in the regulation of apoptotic and necroptotic signaling across various cellular pathways involved in development, innate immunity, and disease.
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Grants
- AS-TP-107-L16, AS-TP-107-L16-1, AS-102-TP-B14 and AS-102-TP-B14-2 Academia Sinica
- AS-TP-107-L16-2 and AS-102-TP-B14-1 Academia Sinica
- AS-TP-107-L16-3 Academia Sinica
- MoST 107-2320-B-001-018-, 108-2311-B-001-018-, 109-2311-B-001-016-, and 110-2311-B-001-015- Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
- MoST 107-2320-B-006-062-MY3, and 111-2311-B-006-005-MY3 Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
- MoST 108-2320-B-002-020-MY3, 111-2320-B-002-048-MY3, and 112-2326-B-002-007- Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
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Affiliation(s)
- Chao-Yu Yang
- Genomics Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Chia-I Lien
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, 10002, Taiwan
| | - Yi-Chun Tseng
- Genomics Research Center, Academia Sinica, Taipei, 11529, Taiwan
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Yi-Fan Tu
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Arkadiusz W Kulczyk
- Institute for Quantitative Biomedicine, Rutgers University, Department of Biochemistry and Microbiology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Yen-Chen Lu
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Yin-Ting Wang
- Genomics Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Tsung-Wei Su
- Genomics Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Li-Chung Hsu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, 10002, Taiwan.
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, 10002, Taiwan.
| | - Yu-Chih Lo
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, 70101, Taiwan.
| | - Su-Chang Lin
- Genomics Research Center, Academia Sinica, Taipei, 11529, Taiwan.
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2
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Yaacoub K, Pedeux R, Lafite P, Jarry U, Aci-Sèche S, Bonnet P, Daniellou R, Guillaudeux T. The Identification of New c-FLIP Inhibitors for Restoring Apoptosis in TRAIL-Resistant Cancer Cells. Curr Issues Mol Biol 2024; 46:710-728. [PMID: 38248348 PMCID: PMC10814526 DOI: 10.3390/cimb46010046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 01/23/2024] Open
Abstract
The catalytically inactive caspase-8-homologous protein, c-FLIP, is a potent antiapoptotic protein highly expressed in various types of cancers. c-FLIP competes with caspase-8 for binding to the adaptor protein FADD (Fas-Associated Death Domain) following death receptors' (DRs) activation via the ligands of the TNF-R family. As a consequence, the extrinsic apoptotic signaling pathway involving DRs is inhibited. The inhibition of c-FLIP activity in tumor cells might enhance DR-mediated apoptosis and overcome immune and anticancer drug resistance. Based on an in silico approach, the aim of this work was to identify new small inhibitory molecules able to bind selectively to c-FLIP and block its anti-apoptotic activity. Using a homology 3D model of c-FLIP, an in silico screening of 1880 compounds from the NCI database (National Cancer Institute) was performed. Nine molecules were selected for in vitro assays, based on their binding affinity to c-FLIP and their high selectivity compared to caspase-8. These molecules selectively bind to the Death Effector Domain 2 (DED2) of c-FLIP. We have tested in vitro the inhibitory effect of these nine molecules using the human lung cancer cell line H1703, overexpressing c-FLIP. Our results showed that six of these newly identified compounds efficiently prevent FADD/c-FLIP interactions in a molecular pull-down assay, as well as in a DISC immunoprecipitation assay. The overexpression of c-FLIP in H1703 prevents TRAIL-mediated apoptosis; however, a combination of TRAIL with these selected molecules significantly restored TRAIL-induced cell death by rescuing caspase cleavage and activation. Altogether, our findings indicate that new inhibitory chemical molecules efficiently prevent c-FLIP recruitment into the DISC complex, thus restoring the caspase-8-dependent apoptotic cascade. These results pave the way to design new c-FLIP inhibitory molecules that may serve as anticancer agents in tumors overexpressing c-FLIP.
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Affiliation(s)
- Katherine Yaacoub
- CNRS, INSERM, BIOSIT UAR 3480, US-S018, Rennes University, F-35000 Rennes, France; (K.Y.); (U.J.)
- INSERM, OSS (Oncogenesis Stress Signaling), UMR-S1242, CLCC Eugène Marquis, Rennes University, F-35000 Rennes, France;
| | - Rémy Pedeux
- INSERM, OSS (Oncogenesis Stress Signaling), UMR-S1242, CLCC Eugène Marquis, Rennes University, F-35000 Rennes, France;
| | - Pierre Lafite
- CNRS, ICOA, UMR 7311, Orléans University, F-45067 Orléans, France; (P.L.); (S.A.-S.); (P.B.); (R.D.)
| | - Ulrich Jarry
- CNRS, INSERM, BIOSIT UAR 3480, US-S018, Rennes University, F-35000 Rennes, France; (K.Y.); (U.J.)
| | - Samia Aci-Sèche
- CNRS, ICOA, UMR 7311, Orléans University, F-45067 Orléans, France; (P.L.); (S.A.-S.); (P.B.); (R.D.)
| | - Pascal Bonnet
- CNRS, ICOA, UMR 7311, Orléans University, F-45067 Orléans, France; (P.L.); (S.A.-S.); (P.B.); (R.D.)
| | - Richard Daniellou
- CNRS, ICOA, UMR 7311, Orléans University, F-45067 Orléans, France; (P.L.); (S.A.-S.); (P.B.); (R.D.)
| | - Thierry Guillaudeux
- CNRS, INSERM, BIOSIT UAR 3480, US-S018, Rennes University, F-35000 Rennes, France; (K.Y.); (U.J.)
- INSERM, OSS (Oncogenesis Stress Signaling), UMR-S1242, CLCC Eugène Marquis, Rennes University, F-35000 Rennes, France;
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3
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Santacroce L, Magrone T. Molluscum Contagiosum Virus: Biology and Immune Response. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1451:151-170. [PMID: 38801577 DOI: 10.1007/978-3-031-57165-7_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Molluscum contagiosum virus is a poxvirus belonging to the Poxviridae family, which includes Orthopoxvirus, Parapoxvirus, Yantapoxvirus, Molluscipoxvirus, Smallpox virus, Cowpox virus and Monkeypox virus. MCV belongs to the genus Molluscipoxvirus and has a tropism for skin tissue. MCV infects keratinocytes and, after an incubation period of 2 weeks to 6 weeks, causes a breakdown of the skin barrier with the development of papules of variable size depending on the proper functioning of the immune response (both adaptive and acquired). MCV only infects humans and does not cause viraemia. MCV encodes for several inhibitory proteins responsible to circumvent the immune response through different signalling pathways. Individuals who can be infected with MCV are children, immunocompromised individuals such as organ transplant recipients and Human Immunodeficiency Virus (HIV)-infected individuals. Current treatments to manage MCV-induced lesions are different and include the use of immunomodulators, which, however, do not provide an effective response.
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Affiliation(s)
- Luigi Santacroce
- Section of Microbiology and Virology, Interdisciplinary Department of Medicine, School of Medicine, University of Bari, Bari, Italy.
| | - Thea Magrone
- Section of Microbiology and Virology, Interdisciplinary Department of Medicine, School of Medicine, University of Bari, Bari, Italy
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4
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Montinaro A, Walczak H. Harnessing TRAIL-induced cell death for cancer therapy: a long walk with thrilling discoveries. Cell Death Differ 2023; 30:237-249. [PMID: 36195672 PMCID: PMC9950482 DOI: 10.1038/s41418-022-01059-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 08/25/2022] [Accepted: 08/26/2022] [Indexed: 02/10/2023] Open
Abstract
Tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) can induce apoptosis in a wide variety of cancer cells, both in vitro and in vivo, importantly without killing any essential normal cells. These findings formed the basis for the development of TRAIL-receptor agonists (TRAs) for cancer therapy. However, clinical trials conducted with different types of TRAs have, thus far, afforded only limited therapeutic benefit, as either the respectively chosen agonist showed insufficient anticancer activity or signs of toxicity, or the right TRAIL-comprising combination therapy was not employed. Therefore, in this review we will discuss molecular determinants of TRAIL resistance, the most promising TRAIL-sensitizing agents discovered to date and, importantly, whether any of these could also prove therapeutically efficacious upon cancer relapse following conventional first-line therapies. We will also discuss the more recent progress made with regards to the clinical development of highly active non-immunogenic next generation TRAs. Based thereupon, we next propose how TRAIL resistance might be successfully overcome, leading to the possible future development of highly potent, cancer-selective combination therapies that are based on our current understanding of biology TRAIL-induced cell death. It is possible that such therapies may offer the opportunity to tackle one of the major current obstacles to effective cancer therapy, namely overcoming chemo- and/or targeted-therapy resistance. Even if this were achievable only for certain types of therapy resistance and only for particular types of cancer, this would be a significant and meaningful achievement.
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Affiliation(s)
- Antonella Montinaro
- Centre for Cell Death, Cancer, and Inflammation (CCCI), UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK.
| | - Henning Walczak
- Centre for Cell Death, Cancer, and Inflammation (CCCI), UCL Cancer Institute, University College London, 72 Huntley Street, London, WC1E 6DD, UK.
- CECAD Cluster of Excellence, University of Cologne, 50931, Cologne, Germany.
- Center for Biochemistry, Medical Faculty, Joseph-Stelzmann-Str. 52, University of Cologne, 50931, Cologne, Germany.
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5
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Bai ZQ, Hu K. Expression, purification, and characterization of c-FLIP tandem death effector domains from Escherichia coli. Protein Expr Purif 2022; 200:106168. [PMID: 36084903 DOI: 10.1016/j.pep.2022.106168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 09/01/2022] [Accepted: 09/01/2022] [Indexed: 11/26/2022]
Abstract
Cellular FLICE-like inhibitory protein (c-FLIP) regulates extrinsic apoptosis by controlling procaspase-8 activation through its tandem N-terminal death effector domains (DEDs). Here, we present the expression and purification of c-FLIP tandem DEDs (tDED) from Escherichia coli. We observed that the c-FLIPtDED maintains monomeric form under near-physiological pH condition in vitro. Our results also reveal a significant correlation between the pH conditions and the structure of c-FLIPtDED (F114A). The described methods and results would be helpful for follow-up study on the structural and functional of c-FLIP.
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Affiliation(s)
- Zhi-Qiang Bai
- Innovative Institute of Chinese Medicine and Pharmacy, University of Traditional Chinese Medicine, Chengdu, 611137, China; College of Science, Yunnan Agricultural University, Kunming, 650201, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Kaifeng Hu
- Innovative Institute of Chinese Medicine and Pharmacy, University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China.
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6
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Bai ZQ, Ma X, Liu B, Huang T, Hu K. Solution structure of c-FLIP death effector domains. Biochem Biophys Res Commun 2022; 617:1-6. [PMID: 35688044 DOI: 10.1016/j.bbrc.2022.05.086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 11/28/2022]
Abstract
The formation of death-inducing signaling complex (DISC) and death effector domain (DED) filament initiates extrinsic apoptosis. Recruitment and activation of procaspase-8 at the DISC are regulated by c-FLIP. The interaction between c-FLIP and procaspase-8 is mediated by their tandem DEDs (tDED). However, the structure of c-FLIPtDED and how c-FLIP interferes with procaspase-8 activation at the DISC remain elusive. Here, we solved the monomeric structure of c-FLIPtDED (F114G) at near physiological pH by solution nuclear magnetic resonance (NMR). Structural superimposition reveals c-FLIPtDED (F114G) adopts a structural topology similar to that of procaspase-8tDED. Our results provide a structural basis for understanding how c-FLIP interacts with procaspase-8 and the molecular mechanisms of c-FLIP in regulating cell death.
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Affiliation(s)
- Zhi-Qiang Bai
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Heilongtan, Kunming, 650201, Yunnan, China; Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaofang Ma
- Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Bin Liu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Heilongtan, Kunming, 650201, Yunnan, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Tao Huang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Heilongtan, Kunming, 650201, Yunnan, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kaifeng Hu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Heilongtan, Kunming, 650201, Yunnan, China; Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
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7
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GPCR-mediated EGFR transactivation ameliorates skin toxicities induced by afatinib. Acta Pharmacol Sin 2022; 43:1534-1543. [PMID: 34552215 PMCID: PMC9160022 DOI: 10.1038/s41401-021-00774-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 09/05/2021] [Indexed: 02/07/2023] Open
Abstract
Many G-protein-coupled receptor (GPCR) agonists have been studied for transactivating epidermal growth factor receptor (EGFR) signaling through extracellular or intracellular pathways. Accumulated evidence has confirmed that GPCR transactivation participates in various diseases. However, the clinical application of GPCR transactivation has not been explored, and more translational studies are needed to develop therapies to target GPCR-mediated EGFR transactivation. In cancer patients treated with EGFR inhibitors (EGFRi), especially afatinib, a unique acneiform rash is frequently developed. In this study, we first established the connection between GPCR transactivation and EGFRi-induced skin disease. We examined the ability of three different GPCR agonists to reverse signaling inhibition and ameliorate rash induced by EGFRi. The activation of different agonists follows unique time and kinase patterns. Rats treated with EGFRi show a similar skin phenotype, with rash occurring in the clinic; correspondingly, treatment with GPCR agonists reduced keratinocyte apoptosis, growth retardation and infiltration of inflammatory cytokines by transactivation. This phenomenon demonstrates that EGFR inhibition in keratinocytes regulates key factors associated with rash. Our findings indicate that maintaining EGFR signaling by GPCR agonists might provide a possible therapy for EGFR inhibitor-induced skin toxicities. Our study provides the first example of the translational application of GPCR transactivation in treating diseases.
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8
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Interaction between the Hepatitis B Virus and Cellular FLIP Variants in Viral Replication and the Innate Immune System. Viruses 2022; 14:v14020373. [PMID: 35215970 PMCID: PMC8874586 DOI: 10.3390/v14020373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/28/2022] [Accepted: 02/08/2022] [Indexed: 12/10/2022] Open
Abstract
During viral evolution and adaptation, many viruses have utilized host cellular factors and machinery as their partners. HBx, as a multifunctional viral protein encoded by the hepatitis B virus (HBV), promotes HBV replication and greatly contributes to the development of HBV-associated hepatocellular carcinoma (HCC). HBx interacts with several host factors in order to regulate HBV replication and evolve carcinogenesis. The cellular FADD-like IL-1β-converting enzyme (FLICE)-like inhibitory protein (c-FLIP) is a major factor that functions in a variety of cellular pathways and specifically in apoptosis. It has been shown that the interaction between HBx and c-FLIP determines HBV fate. In this review, we provide a comprehensive and detailed overview of the interplay between c-FLIP and HBV in various environmental circumstances. We describe strategies adapted by HBV to establish its chronic infection. We also summarize the conventional roles of c-FLIP and highlight the functional outcome of the interaction between c-FLIP and HBV or other viruses in viral replication and the innate immune system.
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9
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An engineered construct of cFLIP provides insight into DED1 structure and interactions. Structure 2022; 30:229-239.e5. [PMID: 34800372 PMCID: PMC8818036 DOI: 10.1016/j.str.2021.10.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 08/24/2021] [Accepted: 10/22/2021] [Indexed: 02/05/2023]
Abstract
Cellular FLICE-like inhibitory protein (cFLIP) is a member of the Death Domain superfamily with pivotal roles in many cellular processes and disease states, including cancer and autoimmune disorders. In the context of the death-inducing signaling complex (DISC), cFLIP isoforms regulate extrinsic apoptosis by controlling procaspase-8 activation. The function of cFLIP is mediated through a series of protein-protein interactions, engaging the two N-terminal death effector domains (DEDs). Here, we solve the structure of an engineered DED1 domain of cFLIP using solution nuclear magnetic resonance (NMR) and we define the interaction with FADD and calmodulin, protein-protein interactions that regulate the function of cFLIP in the DISC. cFLIP DED1 assumes a canonical DED fold characterized by six α helices and is able to bind calmodulin and FADD through two separate interfaces. Our results clearly demonstrate the role of DED1 in the cFLIP/FADD association and contribute to the understanding of the assembly of DISC filaments.
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10
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Ivanisenko NV, Seyrek K, Hillert-Richter LK, König C, Espe J, Bose K, Lavrik IN. Regulation of extrinsic apoptotic signaling by c-FLIP: towards targeting cancer networks. Trends Cancer 2021; 8:190-209. [PMID: 34973957 DOI: 10.1016/j.trecan.2021.12.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/30/2021] [Accepted: 12/01/2021] [Indexed: 02/07/2023]
Abstract
The extrinsic pathway is mediated by death receptors (DRs), including CD95 (APO-1/Fas) or TRAILR-1/2. Defects in apoptosis regulation lead to cancer and other malignancies. The master regulator of the DR networks is the cellular FLICE inhibitory protein (c-FLIP). In addition to its key role in apoptosis, c-FLIP may exert other cellular functions, including control of necroptosis, pyroptosis, nuclear factor κB (NF-κB) activation, and tumorigenesis. To gain further insight into the molecular mechanisms of c-FLIP action in cancer networks, we focus on the structure, isoforms, interactions, and post-translational modifications of c-FLIP. We also discuss various avenues to target c-FLIP in cancer cells for therapeutic benefit.
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Affiliation(s)
- Nikita V Ivanisenko
- The Federal Research Center Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia; Artificial Intelligence Research Institute, Moscow, Russia
| | - Kamil Seyrek
- Translational Inflammation Research, Medical Faculty, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany
| | - Laura K Hillert-Richter
- Translational Inflammation Research, Medical Faculty, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany
| | - Corinna König
- Translational Inflammation Research, Medical Faculty, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany
| | - Johannes Espe
- Translational Inflammation Research, Medical Faculty, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany
| | - Kakoli Bose
- Advanced Centre for Treatment, Research and Education in Cancer (ACTREC), Tata Memorial Centre, Kharghar, Navi Mumbai 410210, India; Homi Bhabha National Institute, BARC Training School Complex, Anushaktinagar, Mumbai 400094, India
| | - Inna N Lavrik
- The Federal Research Center Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia; Translational Inflammation Research, Medical Faculty, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany.
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11
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Farina B, Pirone L, D’Abrosca G, Della Valle M, Russo L, Isernia C, Sassano M, Del Gatto A, Di Gaetano S, Zaccaro L, Malgieri G, Pedone EM, Fattorusso R. Screening a Molecular Fragment Library to Modulate the PED/PEA15-Phospholipase D1 Interaction in Cellular Lysate Environments. ACS Chem Biol 2021; 16:2798-2807. [PMID: 34825823 DOI: 10.1021/acschembio.1c00688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The overexpression of PED/PEA15, the phosphoprotein enriched in diabetes/phosphoprotein enriched in the astrocytes 15 protein (here referred simply to as PED), observed in some forms of type II diabetes, reduces the transport of insulin-stimulated glucose by binding to the phospholipase D1 (PLD1). The inhibition of the PED/PLD1 interaction was shown to restore basal glucose transport, indicating PED as a pharmacological target for the development of drugs capable of improving insulin sensitivity and glucose tolerance. We here report the identification and selection of PED ligands by means of NMR screening of a library of small organic molecules, NMR characterization of the PED/PLD1 interaction in lysates of cells expressing PLD1, and modulation of such interactions using BPH03, the best selected ligand. Overall, we complement the available literature data by providing detailed information on the structural determinants of the PED/PLD1 interaction in a cellular lysate environment and indicate BPH03 as a precious scaffold for the development of novel compounds that are able to modulate such interactions with possible therapeutic applications in type II diabetes.
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Affiliation(s)
- Biancamaria Farina
- Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, 80134 Napoli, Italy
| | - Luciano Pirone
- Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, 80134 Napoli, Italy
| | - Gianluca D’Abrosca
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania─L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Maria Della Valle
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania─L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Luigi Russo
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania─L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Carla Isernia
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania─L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Marica Sassano
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania─L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Annarita Del Gatto
- Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, 80134 Napoli, Italy
| | - Sonia Di Gaetano
- Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, 80134 Napoli, Italy
| | - Laura Zaccaro
- Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, 80134 Napoli, Italy
| | - Gaetano Malgieri
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania─L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
| | - Emilia M. Pedone
- Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, 80134 Napoli, Italy
| | - Roberto Fattorusso
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania─L. Vanvitelli, Via Vivaldi 43, 81100 Caserta, Italy
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12
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Mahdizadeh SJ, Thomas M, Eriksson LA. Reconstruction of the Fas-Based Death-Inducing Signaling Complex (DISC) Using a Protein-Protein Docking Meta-Approach. J Chem Inf Model 2021; 61:3543-3558. [PMID: 34196179 PMCID: PMC8389534 DOI: 10.1021/acs.jcim.1c00301] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The death-inducing signaling complex (DISC) is a fundamental multiprotein complex, which triggers the extrinsic apoptosis pathway through stimulation by death ligands. DISC consists of different death domain (DD) and death effector domain (DED) containing proteins such as the death receptor Fas (CD95) in complex with FADD, procaspase-8, and cFLIP. Despite many experimental and theoretical studies in this area, there is no global agreement neither on the DISC architecture nor on the mechanism of action of the involved species. In the current work, we have tried to reconstruct the DISC structure by identifying key protein interactions using a new protein-protein docking meta-approach. We combined the benefits of five of the most employed protein-protein docking engines, HADDOCK, ClusPro, HDOCK, GRAMM-X, and ZDOCK, in order to improve the accuracy of the predicted docking complexes. Free energy of binding and hot spot interacting residues were calculated and determined for each protein-protein interaction using molecular mechanics generalized Born surface area and alanine scanning techniques, respectively. In addition, a series of in-cellulo protein-fragment complementation assays were conducted to validate the protein-protein docking procedure. The results show that the DISC formation initiates by dimerization of adjacent FasDD trimers followed by recruitment of FADD through homotypic DD interactions with the oligomerized death receptor. Furthermore, the in-silico outcomes indicate that cFLIP cannot bind directly to FADD; instead, cFLIP recruitment to the DISC is a hierarchical and cooperative process where FADD initially recruits procaspase-8, which in turn recruits and heterodimerizes with cFLIP. Finally, a possible structure of the entire DISC is proposed based on the docking results.
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Affiliation(s)
- Sayyed Jalil Mahdizadeh
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30 Göteborg, Sweden
| | - Melissa Thomas
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30 Göteborg, Sweden
| | - Leif A Eriksson
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30 Göteborg, Sweden
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13
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Kaur G, Iyer LM, Burroughs AM, Aravind L. Bacterial death and TRADD-N domains help define novel apoptosis and immunity mechanisms shared by prokaryotes and metazoans. eLife 2021; 10:70394. [PMID: 34061031 PMCID: PMC8195603 DOI: 10.7554/elife.70394] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 05/23/2021] [Indexed: 12/12/2022] Open
Abstract
Several homologous domains are shared by eukaryotic immunity and programmed cell-death systems and poorly understood bacterial proteins. Recent studies show these to be components of a network of highly regulated systems connecting apoptotic processes to counter-invader immunity, in prokaryotes with a multicellular habit. However, the provenance of key adaptor domains, namely those of the Death-like and TRADD-N superfamilies, a quintessential feature of metazoan apoptotic systems, remained murky. Here, we use sensitive sequence analysis and comparative genomics methods to identify unambiguous bacterial homologs of the Death-like and TRADD-N superfamilies. We show the former to have arisen as part of a radiation of effector-associated α-helical adaptor domains that likely mediate homotypic interactions bringing together diverse effector and signaling domains in predicted bacterial apoptosis- and counter-invader systems. Similarly, we show that the TRADD-N domain defines a key, widespread signaling bridge that links effector deployment to invader-sensing in multicellular bacterial and metazoan counter-invader systems. TRADD-N domains are expanded in aggregating marine invertebrates and point to distinctive diversifying immune strategies probably directed both at RNA and retroviruses and cellular pathogens that might infect such communities. These TRADD-N and Death-like domains helped identify several new bacterial and metazoan counter-invader systems featuring underappreciated, common functional principles: the use of intracellular invader-sensing lectin-like (NPCBM and FGS), transcription elongation GreA/B-C, glycosyltransferase-4 family, inactive NTPase (serving as nucleic acid receptors), and invader-sensing GTPase switch domains. Finally, these findings point to the possibility of multicellular bacteria-stem metazoan symbiosis in the emergence of the immune/apoptotic systems of the latter.
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Affiliation(s)
- Gurmeet Kaur
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, United States
| | - Lakshminarayan M Iyer
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, United States
| | - A Maxwell Burroughs
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, United States
| | - L Aravind
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, United States
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14
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Structure, Activation and Regulation of NLRP3 and AIM2 Inflammasomes. Int J Mol Sci 2021; 22:ijms22020872. [PMID: 33467177 PMCID: PMC7830601 DOI: 10.3390/ijms22020872] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/23/2020] [Accepted: 01/11/2021] [Indexed: 12/12/2022] Open
Abstract
The inflammasome is a three-component (sensor, adaptor, and effector) filamentous signaling platform that shields from multiple pathogenic infections by stimulating the proteolytical maturation of proinflammatory cytokines and pyroptotic cell death. The signaling process initiates with the detection of endogenous and/or external danger signals by specific sensors, followed by the nucleation and polymerization from sensor to downstream adaptor and then to the effector, caspase-1. Aberrant activation of inflammasomes promotes autoinflammatory diseases, cancer, neurodegeneration, and cardiometabolic disorders. Therefore, an equitable level of regulation is required to maintain the equilibrium between inflammasome activation and inhibition. Recent advancement in the structural and mechanistic understanding of inflammasome assembly potentiates the emergence of novel therapeutics against inflammasome-regulated diseases. In this review, we have comprehensively discussed the recent and updated insights into the structure of inflammasome components, their activation, interaction, mechanism of regulation, and finally, the formation of densely packed filamentous inflammasome complex that exists as micron-sized punctum in the cells and mediates the immune responses.
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15
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Suraweera CD, Hinds MG, Kvansakul M. Poxviral Strategies to Overcome Host Cell Apoptosis. Pathogens 2020; 10:pathogens10010006. [PMID: 33374867 PMCID: PMC7823800 DOI: 10.3390/pathogens10010006] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/17/2020] [Accepted: 12/17/2020] [Indexed: 12/17/2022] Open
Abstract
Apoptosis is a form of cellular suicide initiated either via extracellular (extrinsic apoptosis) or intracellular (intrinsic apoptosis) cues. This form of programmed cell death plays a crucial role in development and tissue homeostasis in multicellular organisms and its dysregulation is an underlying cause for many diseases. Intrinsic apoptosis is regulated by members of the evolutionarily conserved B-cell lymphoma-2 (Bcl-2) family, a family that consists of pro- and anti-apoptotic members. Bcl-2 genes have also been assimilated by numerous viruses including pox viruses, in particular the sub-family of chordopoxviridae, a group of viruses known to infect almost all vertebrates. The viral Bcl-2 proteins are virulence factors and aid the evasion of host immune defenses by mimicking the activity of their cellular counterparts. Viral Bcl-2 genes have proved essential for the survival of virus infected cells and structural studies have shown that though they often share very little sequence identity with their cellular counterparts, they have near-identical 3D structures. However, their mechanisms of action are varied. In this review, we examine the structural biology, molecular interactions, and detailed mechanism of action of poxvirus encoded apoptosis inhibitors and how they impact on host–virus interactions to ultimately enable successful infection and propagation of viral infections.
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Affiliation(s)
- Chathura D. Suraweera
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia;
| | - Mark G. Hinds
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3052, Australia
- Correspondence: (M.G.H.); (M.K.)
| | - Marc Kvansakul
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia;
- Correspondence: (M.G.H.); (M.K.)
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16
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Bai ZQ, Liu B, Ma X, Hu K. Backbone and side-chain chemical shift assignments of a cellular FLICE-inhibitory protein (c-FLIP S). BIOMOLECULAR NMR ASSIGNMENTS 2020; 14:239-243. [PMID: 32506385 DOI: 10.1007/s12104-020-09953-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
Cellular FLICE-inhibitory protein (c-FLIP), which is involved in regulating the apoptosis of the extrinsic cell death pathway contains two death effector domains (DED). There are several splicing variants including short-form (c-FLIPS) and long-form (c-FLIPL). The death-inducing signaling complex (DISC) initiates apoptosis and programmed necrosis, DISC assembly and activation are regulated by c-FLIP. Here we report the NMR chemical shift assignments of c-FLIPs, which pave the way for investigating the molecular basis of the anti-apoptotic function of c-FLIPS.
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Affiliation(s)
- Zhi-Qiang Bai
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Heilongtan, Kunming, 650201, Yunnan, People's Republic of China
- Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bin Liu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Heilongtan, Kunming, 650201, Yunnan, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaofang Ma
- Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Kaifeng Hu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Heilongtan, Kunming, 650201, Yunnan, People's Republic of China.
- Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
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17
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Kretz AL, Trauzold A, Hillenbrand A, Knippschild U, Henne-Bruns D, von Karstedt S, Lemke J. TRAILblazing Strategies for Cancer Treatment. Cancers (Basel) 2019; 11:cancers11040456. [PMID: 30935038 PMCID: PMC6521007 DOI: 10.3390/cancers11040456] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 03/25/2019] [Accepted: 03/26/2019] [Indexed: 01/07/2023] Open
Abstract
In the late 1990s, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), a member of the TNF-family, started receiving much attention for its potential in cancer therapy, due to its capacity to induce apoptosis selectively in tumour cells in vivo. TRAIL binds to its membrane-bound death receptors TRAIL-R1 (DR4) and TRAIL-R2 (DR5) inducing the formation of a death-inducing signalling complex (DISC) thereby activating the apoptotic cascade. The ability of TRAIL to also induce apoptosis independently of p53 makes TRAIL a promising anticancer agent, especially in p53-mutated tumour entities. Thus, several so-called TRAIL receptor agonists (TRAs) were developed. Unfortunately, clinical testing of these TRAs did not reveal any significant anticancer activity, presumably due to inherent or acquired TRAIL resistance of most primary tumour cells. Since the potential power of TRAIL-based therapies still lies in TRAIL's explicit cancer cell-selectivity, a desirable approach going forward for TRAIL-based cancer therapy is the identification of substances that sensitise tumour cells for TRAIL-induced apoptosis while sparing normal cells. Numerous of such TRAIL-sensitising strategies have been identified within the last decades. However, many of these approaches have not been verified in animal models, and therefore potential toxicity of these approaches has not been taken into consideration. Here, we critically summarise and discuss the status quo of TRAIL signalling in cancer cells and strategies to force tumour cells into undergoing apoptosis triggered by TRAIL as a cancer therapeutic approach. Moreover, we provide an overview and outlook on innovative and promising future TRAIL-based therapeutic strategies.
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Affiliation(s)
- Anna-Laura Kretz
- Department of General and Visceral Surgery, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Anna Trauzold
- Institute for Experimental Cancer Research, University of Kiel, 24105 Kiel, Germany.
- Clinic for General Surgery, Visceral, Thoracic, Transplantation and Pediatric Surgery, University Hospital Schleswig-Holstein, 24105 Kiel, Germany.
| | - Andreas Hillenbrand
- Department of General and Visceral Surgery, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Uwe Knippschild
- Department of General and Visceral Surgery, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Doris Henne-Bruns
- Department of General and Visceral Surgery, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Silvia von Karstedt
- Department of Translational Genomics, University Hospital Cologne, Weyertal 115b, 50931 Cologne, Germany.
- Cologne Excellence Cluster on Cellular Stress Response in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann Straße 26, 50931 Cologne, Germany.
| | - Johannes Lemke
- Department of General and Visceral Surgery, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
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18
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Pan L, Fu TM, Zhao W, Zhao L, Chen W, Qiu C, Liu W, Liu Z, Piai A, Fu Q, Chen S, Wu H, Chou JJ. Higher-Order Clustering of the Transmembrane Anchor of DR5 Drives Signaling. Cell 2019; 176:1477-1489.e14. [PMID: 30827683 DOI: 10.1016/j.cell.2019.02.001] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/14/2018] [Accepted: 01/29/2019] [Indexed: 12/18/2022]
Abstract
Receptor clustering on the cell membrane is critical in the signaling of many immunoreceptors, and this mechanism has previously been attributed to the extracellular and/or the intracellular interactions. Here, we report an unexpected finding that for death receptor 5 (DR5), a receptor in the tumor necrosis factor receptor superfamily, the transmembrane helix (TMH) alone in the receptor directly assembles a higher-order structure to drive signaling and that this structure is inhibited by the unliganded ectodomain. Nuclear magnetic resonance structure of the TMH in bicelles shows distinct trimerization and dimerization faces, allowing formation of dimer-trimer interaction networks. Single-TMH mutations that disrupt either trimerization or dimerization abolish ligand-induced receptor activation. Surprisingly, proteolytic removal of the DR5 ectodomain can fully activate downstream signaling in the absence of ligand. Our data suggest a receptor activation mechanism in which binding of ligand or antibodies to overcome the pre-ligand autoinhibition allows TMH clustering and thus signaling.
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Affiliation(s)
- Liqiang Pan
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Tian-Min Fu
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Wenbin Zhao
- Institute of Drug Metabolism and Pharmaceutical Analysis and Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, 310058 Hangzhou, China
| | - Linlin Zhao
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Wen Chen
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Chixiao Qiu
- Institute of Drug Metabolism and Pharmaceutical Analysis and Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, 310058 Hangzhou, China
| | - Wenhui Liu
- Institute of Drug Metabolism and Pharmaceutical Analysis and Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, 310058 Hangzhou, China
| | - Zhijun Liu
- National Facility for Protein Science in Shanghai, ZhangJiang Lab, Chinese Academy of Sciences, 201210 Shanghai, China
| | - Alessandro Piai
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Qingshan Fu
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Shuqing Chen
- Institute of Drug Metabolism and Pharmaceutical Analysis and Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, 310058 Hangzhou, China.
| | - Hao Wu
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA.
| | - James J Chou
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute at Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA.
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19
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Yuan W, Ibáñez CF, Lin Z. Death domain of p75 neurotrophin receptor: a structural perspective on an intracellular signalling hub. Biol Rev Camb Philos Soc 2019; 94:1282-1293. [PMID: 30762293 DOI: 10.1111/brv.12502] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 01/23/2019] [Accepted: 01/24/2019] [Indexed: 12/19/2022]
Abstract
The death domain (DD) is a globular protein motif with a signature feature of an all-helical Greek-key motif. It is a primary mediator of a variety of biological activities, including apoptosis, cell survival and cytoskeletal changes, which are related to many neurodegenerative diseases, neurotrauma, and cancers. DDs exist in a wide range of signalling proteins including p75 neurotrophin receptor (p75NTR ), a member of the tumour necrosis factor receptor superfamily. The specific signalling mediated by p75NTR in a given cell depends on the type of ligand engaging the extracellular domain and the recruitment of cytosolic interactors to the intracellular domain, especially the DD, of the receptor. In solution, the p75NTR -DDs mainly form a symmetric non-covalent homodimer. In response to extracellular signals, conformational changes in the p75NTR extracellular domain (ECD) propagate to the p75NTR -DD through the disulfide-bonded transmembrane domain (TMD) and destabilize the p75NTR -DD homodimer, leading to protomer separation and exposure of binding sites on the DD surface. In this review, we focus on recent advances in the study of the structural mechanism of p75NTR -DD signalling through recruitment of diverse intracellular interactors for the regulation and control of diverse functional outputs.
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Affiliation(s)
- Wensu Yuan
- School of Life Sciences, Tianjin University, Tianjin, 300072, People's Republic of China
| | - Carlos F Ibáñez
- Department of Physiology, National University of Singapore, 117456, Singapore.,Life Sciences Institute, National University of Singapore, 117456, Singapore.,Department of Cell & Molecular Biology, Karolinska Institute, 17165, Stockholm, Sweden
| | - Zhi Lin
- School of Life Sciences, Tianjin University, Tianjin, 300072, People's Republic of China.,Department of Physiology, National University of Singapore, 117456, Singapore.,Life Sciences Institute, National University of Singapore, 117456, Singapore
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20
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Kim CM, Ha HJ, Kwon S, Jeong JH, Lee SH, Kim YG, Lee CS, Lee JH, Park HH. Structural transformation-mediated dimerization of caspase recruitment domain revealed by the crystal structure of CARD-only protein in frog virus 3. J Struct Biol 2019; 205:189-195. [DOI: 10.1016/j.jsb.2018.12.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 12/19/2018] [Accepted: 12/22/2018] [Indexed: 10/27/2022]
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21
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Townsend JR, Stout JR, Jajtner AR, Church DD, Beyer KS, Riffe JJ, Muddle TWD, Herrlinger KL, Fukuda DH, Hoffman JR. Polyphenol supplementation alters intramuscular apoptotic signaling following acute resistance exercise. Physiol Rep 2019; 6. [PMID: 29380956 PMCID: PMC5789717 DOI: 10.14814/phy2.13552] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 11/15/2017] [Accepted: 11/25/2017] [Indexed: 02/06/2023] Open
Abstract
The purpose of this study was to examine the effects of 28‐days of supplementation with an aqueous proprietary polyphenol blend (PPB) sourced from Camellia sinensis on intramuscular apoptotic signaling following an acute lower‐body resistance exercise protocol and subsequent recovery. Untrained males (n = 38, 21.8 ± 2.7 years, 173.4 ± 7.9 cm, 77.6 ± 14.6 kg) were randomized to PPB (n = 14), placebo (PL; n = 14) or control (CON; n = 10). Participants completed a lower‐body resistance exercise protocol comprised of the squat, leg press, and leg extension exercises. Skeletal muscle microbiopsies were obtained from the vastus lateralis preexercise (PRE), 1‐h (1HR), 5‐h (5HR), and 48‐h (48HR) post‐resistance exercise. Apoptotic signaling pathways were quantified using multiplex signaling assay kits to quantify total proteins (Caspase 3, 8, 9) and markers of phosphorylation status (JNK, FADD, p53, BAD, Bcl‐2). Changes in markers of muscle damage and intramuscular signaling were analyzed via separate repeated measures analysis of variance (ANOVA). Change in Bcl‐2 phosphorylation at 1H was significantly greater in PL compared to CON (P = 0.001). BAD phosphorylation was significantly elevated at 5H in PL compared to PPB (P = 0.015) and CON (P = 0.006). The change in JNK phosphorylation was significantly greater in PPB (P = 0.009), and PL (P = 0.017) compared to CON at 1H, while the change for PL was elevated compared to CON at 5H (P = 0.002). A main effect was observed (P < 0.05) at 1H, 5H, and 48H for p53 and Caspase 8, with Caspase 3 and Caspase 9 elevated at 48H. These data indicate that chronic supplementation with PPB alters apoptotic signaling in skeletal muscle following acute muscle‐damaging resistance exercise.
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Affiliation(s)
- Jeremy R Townsend
- Exercise and Nutrition Science Graduate Program, Lipscomb University, Nashville, Tennessee
| | - Jeffrey R Stout
- Institute of Exercise Physiology and Wellness, University of Central Florida, Orlando, Florida
| | - Adam R Jajtner
- Human Performance Laboratory, Kent State University, Kent, Ohio
| | - David D Church
- Institute of Exercise Physiology and Wellness, University of Central Florida, Orlando, Florida
| | - Kyle S Beyer
- Institute of Exercise Physiology and Wellness, University of Central Florida, Orlando, Florida
| | - Joshua J Riffe
- Institute of Exercise Physiology and Wellness, University of Central Florida, Orlando, Florida
| | - Tyler W D Muddle
- Institute of Exercise Physiology and Wellness, University of Central Florida, Orlando, Florida
| | | | - David H Fukuda
- Institute of Exercise Physiology and Wellness, University of Central Florida, Orlando, Florida
| | - Jay R Hoffman
- Institute of Exercise Physiology and Wellness, University of Central Florida, Orlando, Florida
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22
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Nanson JD, Kobe B, Ve T. Death, TIR, and RHIM: Self-assembling domains involved in innate immunity and cell-death signaling. J Leukoc Biol 2018; 105:363-375. [PMID: 30517972 DOI: 10.1002/jlb.mr0318-123r] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 10/31/2018] [Accepted: 11/01/2018] [Indexed: 12/14/2022] Open
Abstract
The innate immune system consists of pattern recognition receptors (PRRs) that detect pathogen- and endogenous danger-associated molecular patterns (PAMPs and DAMPs), initiating signaling pathways that lead to the induction of cytokine expression, processing of pro-inflammatory cytokines, and induction of cell-death responses. An emerging concept in these pathways and associated processes is signaling by cooperative assembly formation (SCAF), which involves formation of higher order oligomeric complexes, and enables rapid and strongly amplified signaling responses to minute amounts of stimulus. Many of these signalosomes assemble through homotypic interactions of members of the death-fold (DF) superfamily, Toll/IL-1 receptor (TIR) domains, or the RIP homotypic interaction motifs (RHIM). We review the current understanding of the structure and function of these domains and their molecular interactions with a particular focus on higher order assemblies.
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Affiliation(s)
- Jeffrey D Nanson
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, Queensland, 4072, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, Queensland, 4072, Australia
| | - Thomas Ve
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, Queensland, 4072, Australia.,Institute for Glycomics, Griffith University, Southport, Queensland, 4222, Australia
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23
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Shen C, Pei J, Guo X, Zhou L, Li Q, Quan J. Structural basis for dimerization of the death effector domain of the F122A mutant of Caspase-8. Sci Rep 2018; 8:16723. [PMID: 30425291 PMCID: PMC6233201 DOI: 10.1038/s41598-018-35153-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 10/19/2018] [Indexed: 11/09/2022] Open
Abstract
Caspase-8 is an apoptotic protease that is activated by a proximity-induced dimerization mechanism within the death-inducing signaling complex (DISC). The death effector domain (DED) of caspase-8 is involved in protein-protein interactions and is essential for the activation. Here, we report two crystal structures of the dimeric DEDs of the F122A mutant of caspase-8, both of which illustrate a novel domain-swapped dimerization, while differ in the relative orientation of the two subunits and the solvent exposure of the conserved hydrophobic patch Phe122/Leu123. We demonstrate that mutations disrupting the dimerization of the DEDs abrogate the formation of cellular death effector filaments (DEFs) and the induced apoptosis by overexpressed DEDs. Furthermore, such dimerization-disrupting mutations also impair the activation of the full-length caspase-8 and the downstream apoptosis cascade. The structures provide new insights into understanding the mechanism underlying the activation of procaspase-8 within the DISC and DEFs.
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Affiliation(s)
- Chen Shen
- State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Jianwen Pei
- State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Xiaomin Guo
- State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Lu Zhou
- School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Qinkai Li
- State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Junmin Quan
- State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China.
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24
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Nanson JD, Rahaman MH, Ve T, Kobe B. Regulation of signaling by cooperative assembly formation in mammalian innate immunity signalosomes by molecular mimics. Semin Cell Dev Biol 2018; 99:96-114. [PMID: 29738879 DOI: 10.1016/j.semcdb.2018.05.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 03/18/2018] [Accepted: 05/04/2018] [Indexed: 12/16/2022]
Abstract
Innate immunity pathways constitute the first line of defense against infections and cellular damage. An emerging concept in these pathways is that signaling involves the formation of finite (e.g. rings in NLRs) or open-ended higher-order assemblies (e.g. filamentous assemblies by members of the death-fold family and TIR domains). This signaling by cooperative assembly formation (SCAF) mechanism allows rapid and strongly amplified responses to minute amounts of stimulus. While the characterization of the molecular mechanisms of SCAF has seen rapid progress, little is known about its regulation. One emerging theme involves proteins produced both in host cells and by pathogens that appear to mimic the signaling components. Recently characterized examples involve the capping of the filamentous assemblies formed by caspase-1 CARDs by the CARD-only protein INCA, and those formed by caspase-8 by the DED-containing protein MC159. By contrast, the CARD-only protein ICEBERG and the DED-containing protein cFLIP incorporate into signaling filaments and presumably interfere with proximity based activation of caspases. We review selected examples of SCAF in innate immunity pathways and focus on the current knowledge on signaling component mimics produced by mammalian and pathogen cells and what is known about their mechanisms of action.
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Affiliation(s)
- Jeffrey D Nanson
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Md Habibur Rahaman
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Thomas Ve
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia; Institute for Glycomics, Griffith University, Southport, QLD, 4222, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia.
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25
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Fancy RM, Kim H, Napier T, Buchsbaum DJ, Zinn KR, Song Y. Calmodulin antagonist enhances DR5-mediated apoptotic signaling in TRA-8 resistant triple negative breast cancer cells. J Cell Biochem 2018; 119:6216-6230. [PMID: 29663486 DOI: 10.1002/jcb.26848] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 03/09/2018] [Indexed: 01/25/2023]
Abstract
Patients with triple negative breast cancer (TNBC) have no successful "targeted" treatment modality, which represents a priority for novel therapy strategies. Upregulated death receptor 5 (DR5) expression levels in breast cancer cells compared to normal cells enable TRA-8, a DR5 specific agonistic antibody, to specifically target malignant cells for apoptosis without inducing normal hepatocyte apoptosis. Drug resistance is a common obstacle in TRAIL-based therapy for TNBC. Calmodulin (CaM) is overexpressed in breast cancer. In this study, we characterized the novel function of CaM antagonist in enhancing TRA-8 induced cytotoxicity in TRA-8 resistant TNBC cells and its underlying molecular mechanisms. Results demonstrated that CaM antagonist(s) enhanced TRA-8 induced cytotoxicity in a concentration and time-dependent manner for TRA-8 resistant TNBC cells. CaM directly bound to DR5 in a Ca2+ dependent manner, and CaM siRNA promoted DR5 recruitment of FADD and caspase-8 for DISC formation and TRA-8 activated caspase cleavage for apoptosis in TRA-8 resistant TNBC cells. CaM antagonist, trifluoperazine, enhanced TRA-8 activated DR5 oligomerization, DR5-mediated DISC formation, and TRA-8 activated caspase cleavage for apoptosis, and decreased anti-apoptotic pERK, pAKT, XIAP, and cIAP-1 expression in TRA-8 resistant TNBC cells. These results suggest that CaM could be a key regulator to mediate DR5-mediated apoptotic signaling, and suggests a potential strategy for using CaM antagonists to overcome drug resistance of TRAIL-based therapy for TRA-8 resistant TNBC.
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Affiliation(s)
- Romone M Fancy
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama
| | - Harrison Kim
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Tiara Napier
- Hospital, University of Alabama at Birmingham, Birmingham, Alabama
| | - Donald J Buchsbaum
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Kurt R Zinn
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Radiology and Biomedical Engineering, Michigan State University, East Lansing, Michigan
| | - Yuhua Song
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama
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Abstract
Roles for cell death in development, homeostasis, and the control of infections and cancer have long been recognized. Although excessive cell damage results in passive necrosis, cells can be triggered to engage molecular programs that result in cell death. Such triggers include cellular stress, oncogenic signals that engage tumor suppressor mechanisms, pathogen insults, and immune mechanisms. The best-known forms of programmed cell death are apoptosis and a recently recognized regulated necrosis termed necroptosis. Of the two best understood pathways of apoptosis, the extrinsic and intrinsic (mitochondrial) pathways, the former is induced by the ligation of death receptors, a subset of the TNF receptor (TNFR) superfamily. Ligation of these death receptors can also induce necroptosis. The extrinsic apoptosis and necroptosis pathways regulate each other and their balance determines whether cells live. Integral in the regulation and initiation of death receptor-mediated activation of programmed cell death is the aspartate-specific cysteine protease (caspase)-8. This review describes the role of caspase-8 in the initiation of extrinsic apoptosis execution and the mechanism by which caspase-8 inhibits necroptosis. The importance of caspase-8 in the development and homeostasis and the way that dysfunctional caspase-8 may contribute to the development of malignancies in mice and humans are also explored.
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Affiliation(s)
- Bart Tummers
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Douglas R Green
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
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27
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Nichols DB, De Martini W, Cottrell J. Poxviruses Utilize Multiple Strategies to Inhibit Apoptosis. Viruses 2017; 9:v9080215. [PMID: 28786952 PMCID: PMC5580472 DOI: 10.3390/v9080215] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/31/2017] [Accepted: 08/02/2017] [Indexed: 12/11/2022] Open
Abstract
Cells have multiple means to induce apoptosis in response to viral infection. Poxviruses must prevent activation of cellular apoptosis to ensure successful replication. These viruses devote a substantial portion of their genome to immune evasion. Many of these immune evasion products expressed during infection antagonize cellular apoptotic pathways. Poxvirus products target multiple points in both the extrinsic and intrinsic apoptotic pathways, thereby mitigating apoptosis during infection. Interestingly, recent evidence indicates that poxviruses also hijack cellular means of eliminating apoptotic bodies as a means to spread cell to cell through a process called apoptotic mimicry. Poxviruses are the causative agent of many human and veterinary diseases. Further, there is substantial interest in developing these viruses as vectors for a variety of uses including vaccine delivery and as oncolytic viruses to treat certain human cancers. Therefore, an understanding of the molecular mechanisms through which poxviruses regulate the cellular apoptotic pathways remains a top research priority. In this review, we consider anti-apoptotic strategies of poxviruses focusing on three relevant poxvirus genera: Orthopoxvirus, Molluscipoxvirus, and Leporipoxvirus. All three genera express multiple products to inhibit both extrinsic and intrinsic apoptotic pathways with many of these products required for virulence.
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Affiliation(s)
- Daniel Brian Nichols
- Department of Biological Sciences, Seton Hall University, South Orange, NJ 07039, USA.
| | - William De Martini
- Department of Biological Sciences, Seton Hall University, South Orange, NJ 07039, USA.
| | - Jessica Cottrell
- Department of Biological Sciences, Seton Hall University, South Orange, NJ 07039, USA.
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Molluscum Contagiosum Virus MC159 Abrogates cIAP1-NEMO Interactions and Inhibits NEMO Polyubiquitination. J Virol 2017; 91:JVI.00276-17. [PMID: 28515292 DOI: 10.1128/jvi.00276-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/05/2017] [Indexed: 12/20/2022] Open
Abstract
Molluscum contagiosum virus (MCV) is a dermatotropic poxvirus that causes benign skin lesions. MCV lesions persist because of virally encoded immune evasion molecules that inhibit antiviral responses. The MCV MC159 protein suppresses NF-κB activation, a powerful antiviral response, via interactions with the NF-κB essential modulator (NEMO) subunit of the IκB kinase (IKK) complex. Binding of MC159 to NEMO does not disrupt the IKK complex, implying that MC159 prevents IKK activation via an as-yet-unidentified strategy. Here, we demonstrated that MC159 inhibited NEMO polyubiquitination, a posttranslational modification required for IKK and downstream NF-κB activation. Because MCV cannot be propagated in cell culture, MC159 was expressed independent of infection or during a surrogate vaccinia virus infection to identify how MC159 prevented polyubiquitination. Cellular inhibitor of apoptosis protein 1 (cIAP1) is a cellular E3 ligase that ubiquitinates NEMO. Mutational analyses revealed that MC159 and cIAP1 each bind to the same NEMO region, suggesting that MC159 may competitively inhibit cIAP1-NEMO interactions. Indeed, MC159 prevented cIAP1-NEMO interactions. MC159 also diminished cIAP1-mediated NEMO polyubiquitination and cIAP1-induced NF-κB activation. These data suggest that MC159 competitively binds to NEMO to prevent cIAP1-induced NEMO polyubiquitination. To our knowledge, this is the first report of a viral protein disrupting NEMO-cIAP1 interactions to strategically suppress IKK activation. All viruses must antagonize antiviral signaling events for survival. We hypothesize that MC159 inhibits NEMO polyubiquitination as a clever strategy to manipulate the host cell environment to the benefit of the virus.IMPORTANCE Molluscum contagiosum virus (MCV) is a human-specific poxvirus that causes persistent skin neoplasms. The persistence of MCV has been attributed to viral downregulation of host cell immune responses such as NF-κB activation. We show here that the MCV MC159 protein interacts with the NEMO subunit of the IKK complex to prevent NEMO interactions with the cIAP1 E3 ubiquitin ligase. This interaction correlates with a dampening of cIAP1 to polyubiquitinate NEMO and to activate NF-κB. This inhibition of cIAP1-NEMO interactions is a new viral strategy to minimize IKK activation and to control NEMO polyubiquitination. This research provides new insights into mechanisms that persistent viruses may use to cause long-term infection of host cells.
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Huhtinen A, Hongisto V, Laiho A, Löyttyniemi E, Pijnenburg D, Scheinin M. Gene expression profiles and signaling mechanisms in α 2B-adrenoceptor-evoked proliferation of vascular smooth muscle cells. BMC SYSTEMS BIOLOGY 2017; 11:65. [PMID: 28659168 PMCID: PMC5490158 DOI: 10.1186/s12918-017-0439-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 06/09/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND α2-adrenoceptors are important regulators of vascular tone and blood pressure. Regulation of cell proliferation is a less well investigated consequence of α2-adrenoceptor activation. We have previously shown that α2B-adrenoceptor activation stimulates proliferation of vascular smooth muscle cells (VSMCs). This may be important for blood vessel development and plasticity and for the pathology and therapeutics of cardiovascular disorders. The underlying cellular mechanisms have remained mostly unknown. This study explored pathways of regulation of gene expression and intracellular signaling related to α2B-adrenoceptor-evoked VSMC proliferation. RESULTS The cellular mechanisms and signaling pathways of α2B-adrenoceptor-evoked proliferation of VSMCs are complex and include redundancy. Functional enrichment analysis and pathway analysis identified differentially expressed genes associated with α2B-adrenoceptor-regulated VSMC proliferation. They included the upregulated genes Egr1, F3, Ptgs2 and Serpine1 and the downregulated genes Cx3cl1, Cav1, Rhoa, Nppb and Prrx1. The most highly upregulated gene, Lypd8, represents a novel finding in the VSMC context. Inhibitor library screening and kinase activity profiling were applied to identify kinases in the involved signaling pathways. Putative upstream kinases identified by two different screens included PKC, Raf-1, Src, the MAP kinases p38 and JNK and the receptor tyrosine kinases EGFR and HGF/HGFR. As a novel finding, the Src family kinase Lyn was also identified as a putative upstream kinase. CONCLUSIONS α2B-adrenoceptors may mediate their pro-proliferative effects in VSMCs by promoting the activity of bFGF and PDGF and the growth factor receptors EGFR, HGFR and VEGFR-1/2. The Src family kinase Lyn was also identified as a putative upstream kinase. Lyn is known to be expressed in VSMCs and has been identified as an important regulator of GPCR trafficking and GPCR effects on cell proliferation. Identified Ser/Thr kinases included several PKC isoforms and the β-adrenoceptor kinases 1 and 2. Cross-talk between the signaling mechanisms involved in α2B-adrenoceptor-evoked VSMC proliferation thus appears to involve PKC activation, subsequent changes in gene expression, transactivation of EGFR, and modulation of kinase activities and growth factor-mediated signaling. While many of the identified individual signals were relatively small in terms of effect size, many of them were validated by combining pathway analysis and our integrated screening approach.
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Affiliation(s)
- Anna Huhtinen
- Department of Pharmacology, Drug Development and Therapeutics, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20520 Turku, Finland
- Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
| | - Vesa Hongisto
- Toxicology Division, Misvik Biology Oy, Turku, Finland
| | - Asta Laiho
- Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland
| | - Eliisa Löyttyniemi
- Department of Biostatistics, Department of Clinical Medicine, University of Turku, Turku, Finland
| | - Dirk Pijnenburg
- PamGene International BV, Wolvenhoek 10, 5211HH s’Hertogenbosch, The Netherlands
| | - Mika Scheinin
- Department of Pharmacology, Drug Development and Therapeutics, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20520 Turku, Finland
- Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
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30
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Beaury M, Velagapudi UK, Weber S, Soto C, Talele TT, Nichols DB. The molluscum contagiosum virus death effector domain containing protein MC160 RxDL motifs are not required for its known viral immune evasion functions. Virus Genes 2017; 53:522-531. [PMID: 28425034 DOI: 10.1007/s11262-017-1456-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 04/11/2017] [Indexed: 12/25/2022]
Abstract
The molluscum contagiosum virus (MCV) uses a variety of immune evasion strategies to antagonize host immune responses. Two MCV proteins, MC159 and MC160, contain tandem death effector domains (DEDs). They are reported to inhibit innate immune signaling events such as NF-κB and IRF3 activation, and apoptosis. The RxDL motif of MC159 is required for inhibition of both apoptosis and NF-κB activation. However, the role of the conserved RxDL motif in the MC160 DEDs remained unknown. To answer this question, we performed alanine mutations to neutralize the arginine and aspartate residues present in the MC160 RxDL in both DED1 and DED2. These mutations were further modeled against the structure of the MC159 protein. Surprisingly, the RxDL motif was not required for MC160's ability to inhibit MAVS-induced IFNβ activation. Further, unlike previous results with the MC159 protein, mutations within the RxDL motif of MC160 had no effect on the ability of MC160 to dampen TNF-α-induced NF-κB activation. Molecular modeling predictions revealed no overall changes to the structure in the MC160 protein when the amino acids of both RxDL motifs were mutated to alanine (DED1 = R67A D69A; DED2 = R160A D162A). Taken together, our results demonstrate that the RxDL motifs present in the MC160 DEDs are not required for known functions of the viral protein.
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Affiliation(s)
- Michael Beaury
- Department of Biological Sciences, Seton Hall University, 400 South Orange Ave., South Orange, NJ, 07039, USA
| | - Uday Kiran Velagapudi
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, NY, 11439, USA
| | - Sarah Weber
- Department of Biological Sciences, Seton Hall University, 400 South Orange Ave., South Orange, NJ, 07039, USA
| | - Cassandra Soto
- Department of Biological Sciences, Seton Hall University, 400 South Orange Ave., South Orange, NJ, 07039, USA
| | - Tanaji T Talele
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, NY, 11439, USA
| | - Daniel Brian Nichols
- Department of Biological Sciences, Seton Hall University, 400 South Orange Ave., South Orange, NJ, 07039, USA.
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31
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Park YH, Jeong MS, Jang SB. Structural insights of homotypic interaction domains in the ligand-receptor signal transduction of tumor necrosis factor (TNF). BMB Rep 2017; 49:159-66. [PMID: 26615973 PMCID: PMC4915230 DOI: 10.5483/bmbrep.2016.49.3.205] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Indexed: 11/21/2022] Open
Abstract
Several members of tumor necrosis factor receptor (TNFR) superfamily that these
members activate caspase-8 from death-inducing signaling complex (DISC) in TNF
ligand-receptor signal transduction have been identified. In the extrinsic
pathway, apoptotic signal transduction is induced in death domain (DD)
superfamily; it consists of a hexahelical bundle that contains 80 amino acids.
The DD superfamily includes about 100 members that belong to four subfamilies:
death domain (DD), caspase recruitment domain (CARD), pyrin domain (PYD), and
death effector domain (DED). This superfamily contains key building blocks: with
these blocks, multimeric complexes are formed through homotypic interactions.
Furthermore, each DD-binding event occurs exclusively. The DD superfamily
regulates the balance between death and survival of cells. In this study, the
structures, functions, and unique features of DD superfamily members are
compared with their complexes. By elucidating structural insights of DD
superfamily members, we investigate the interaction mechanisms of DD domains;
these domains are involved in TNF ligand-receptor signaling. These DD
superfamily members play a pivotal role in the development of more specific
treatments of cancer. [BMB Reports 2016; 49(3): 159-166]
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Affiliation(s)
- Young-Hoon Park
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan 46241, Korea
| | - Mi Suk Jeong
- Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan 46241, Korea
| | - Se Bok Jang
- Department of Molecular Biology, College of Natural Sciences, Pusan National University; Genetic Engineering Institute, Pusan National University, Busan 46241, Korea
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32
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Fu TM, Li Y, Lu A, Li Z, Vajjhala PR, Cruz AC, Srivastava DB, DiMaio F, Penczek PA, Siegel RM, Stacey KJ, Egelman EH, Wu H. Cryo-EM Structure of Caspase-8 Tandem DED Filament Reveals Assembly and Regulation Mechanisms of the Death-Inducing Signaling Complex. Mol Cell 2016; 64:236-250. [PMID: 27746017 PMCID: PMC5089849 DOI: 10.1016/j.molcel.2016.09.009] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/10/2016] [Accepted: 09/07/2016] [Indexed: 12/20/2022]
Abstract
Caspase-8 activation can be triggered by death receptor-mediated formation of the death-inducing signaling complex (DISC) and by the inflammasome adaptor ASC. Caspase-8 assembles with FADD at the DISC and with ASC at the inflammasome through its tandem death effector domain (tDED), which is regulated by the tDED-containing cellular inhibitor cFLIP and the viral inhibitor MC159. Here we present the caspase-8 tDED filament structure determined by cryoelectron microscopy. Extensive assembly interfaces not predicted by the previously proposed linear DED chain model were uncovered, and were further confirmed by structure-based mutagenesis in filament formation in vitro and Fas-induced apoptosis and ASC-mediated caspase-8 recruitment in cells. Structurally, the two DEDs in caspase-8 use quasi-equivalent contacts to enable assembly. Using the tDED filament structure as a template, structural analyses reveal the interaction surfaces between FADD and caspase-8 and the distinct mechanisms of regulation by cFLIP and MC159 through comingling and capping, respectively.
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Affiliation(s)
- Tian-Min Fu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Yang Li
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Alvin Lu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Zongli Li
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Parimala R Vajjhala
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - Anthony C Cruz
- Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, NIH, Bethesda, MD 20892, USA
| | - Devendra B Srivastava
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Frank DiMaio
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Pawel A Penczek
- Department of Biochemistry and Molecular Biology, University of Texas-Houston Medical School, Houston, TX 77030, USA
| | - Richard M Siegel
- Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, NIH, Bethesda, MD 20892, USA
| | - Katryn J Stacey
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia; Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908, USA
| | - Hao Wu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA.
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Oroz J, Barrera-Vilarmau S, Alfonso C, Rivas G, de Alba E. ASC Pyrin Domain Self-associates and Binds NLRP3 Protein Using Equivalent Binding Interfaces. J Biol Chem 2016; 291:19487-501. [PMID: 27432880 PMCID: PMC5016686 DOI: 10.1074/jbc.m116.741082] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 07/08/2016] [Indexed: 11/06/2022] Open
Abstract
Death domain superfamily members typically act as adaptors mediating in the assembly of supramolecular complexes with critical apoptosis and inflammation functions. These modular proteins consist of death domains, death effector domains, caspase recruitment domains, and pyrin domains (PYD). Despite the high structural similarity among them, only homotypic interactions participate in complex formation, suggesting that subtle factors differentiate each interaction type. It is thus critical to identify these factors as an essential step toward the understanding of the molecular basis of apoptosis and inflammation. The proteins apoptosis-associated speck-like protein containing a CARD (ASC) and NLRP3 play key roles in the regulation of apoptosis and inflammation through self-association and protein-protein interactions mediated by their PYDs. To better understand the molecular basis of their function, we have characterized ASC and NLRP3 PYD self-association and their intermolecular interaction by solution NMR spectroscopy and analytical ultracentrifugation. We found that ASC self-associates and binds NLRP3 PYD through equivalent protein regions, with higher binding affinity for the latter. These regions are located at opposite sides of the protein allowing multimeric complex formation previously shown in ASC PYD fibril assemblies. We show that NLRP3 PYD coexists in solution as a monomer and highly populated large-order oligomerized species. Despite this, we determined its monomeric three-dimensional solution structure by NMR and characterized its binding to ASC PYD. Using our novel structural data, we propose molecular models of ASC·ASC and ASC·NLRP3 PYD early supramolecular complexes, providing new insights into the molecular mechanisms of inflammasome and apoptosis signaling.
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Affiliation(s)
- Javier Oroz
- From the Centro de Investigaciones Biológicas, Departments of Chemical and Physical Biology and the German Center for Neurodegenerative Diseases (DZNE), ℅Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Göttingen-37077, Germany, and
| | - Susana Barrera-Vilarmau
- From the Centro de Investigaciones Biológicas, Departments of Chemical and Physical Biology and
| | | | | | - Eva de Alba
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, 9 Madrid-28040, Spain, the Health Sciences Research Institute, University of California at Merced, Merced, California 95343
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34
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Hughes MA, Powley IR, Jukes-Jones R, Horn S, Feoktistova M, Fairall L, Schwabe JWR, Leverkus M, Cain K, MacFarlane M. Co-operative and Hierarchical Binding of c-FLIP and Caspase-8: A Unified Model Defines How c-FLIP Isoforms Differentially Control Cell Fate. Mol Cell 2016; 61:834-49. [PMID: 26990987 PMCID: PMC4819448 DOI: 10.1016/j.molcel.2016.02.023] [Citation(s) in RCA: 191] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/22/2016] [Accepted: 02/17/2016] [Indexed: 12/11/2022]
Abstract
The death-inducing signaling complex (DISC) initiates death receptor-induced apoptosis. DISC assembly and activation are controlled by c-FLIP isoforms, which function as pro-apoptotic (c-FLIPL only) or anti-apoptotic (c-FLIPL/c-FLIPS) regulators of procaspase-8 activation. Current models assume that c-FLIP directly competes with procaspase-8 for recruitment to FADD. Using a functional reconstituted DISC, structure-guided mutagenesis, and quantitative LC-MS/MS, we show that c-FLIPL/S binding to the DISC is instead a co-operative procaspase-8-dependent process. FADD initially recruits procaspase-8, which in turn recruits and heterodimerizes with c-FLIPL/S via a hierarchical binding mechanism. Procaspase-8 activation is regulated by the ratio of unbound c-FLIPL/S to procaspase-8, which determines composition of the procaspase-8:c-FLIPL/S heterodimer. Thus, procaspase-8:c-FLIPL exhibits localized enzymatic activity and is preferentially an activator, promoting DED-mediated procaspase-8 oligomer assembly, whereas procaspase-8:c-FLIPS lacks activity and potently blocks procaspase-8 activation. This co-operative hierarchical binding model explains the dual role of c-FLIPL and crucially defines how c-FLIP isoforms differentially control cell fate.
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Affiliation(s)
- Michelle A Hughes
- MRC Toxicology Unit, Hodgkin Building, P.O. Box 138, Lancaster Road, Leicester LE1 9HN, UK
| | - Ian R Powley
- MRC Toxicology Unit, Hodgkin Building, P.O. Box 138, Lancaster Road, Leicester LE1 9HN, UK
| | - Rebekah Jukes-Jones
- MRC Toxicology Unit, Hodgkin Building, P.O. Box 138, Lancaster Road, Leicester LE1 9HN, UK
| | - Sebastian Horn
- Department of Dermatology, Venereology and Allergology, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
| | - Maria Feoktistova
- Department of Dermatology and Allergology, Medical Faculty of the RWTH Aachen, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Louise Fairall
- Henry Wellcome Laboratories of Structural Biology, Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - John W R Schwabe
- Henry Wellcome Laboratories of Structural Biology, Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - Martin Leverkus
- Department of Dermatology and Allergology, Medical Faculty of the RWTH Aachen, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Kelvin Cain
- MRC Toxicology Unit, Hodgkin Building, P.O. Box 138, Lancaster Road, Leicester LE1 9HN, UK.
| | - Marion MacFarlane
- MRC Toxicology Unit, Hodgkin Building, P.O. Box 138, Lancaster Road, Leicester LE1 9HN, UK.
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Functional Comparison of Molluscum Contagiosum Virus vFLIP MC159 with Murine Cytomegalovirus M36/vICA and M45/vIRA Proteins. J Virol 2015; 90:2895-905. [PMID: 26719271 DOI: 10.1128/jvi.02729-15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 12/21/2015] [Indexed: 12/19/2022] Open
Abstract
UNLABELLED Molluscum contagiosum virus (MCV) gene MC159 encodes a viral FLICE inhibitory protein (vFLIP) that inhibits caspase-8-mediated apoptosis. The MC159 protein was also reported to inhibit programmed necrosis (necroptosis) and modulate NF-κB activation by interacting with RIP1 and NEMO. The importance of MC159 during MCV infection has remained unknown, as there is no system for propagation and genetic manipulation of this virus. Here we investigated the functions of MC159 during viral infection using murine cytomegalovirus (MCMV) as a surrogate virus. MC159 was inserted into the MCMV genome, replacing M36 or M45, two MCMV genes with functions similar to those reported for MC159. M36 encodes a viral inhibitor of caspase-8-induced apoptosis (vICA) and M45 a viral inhibitor of RIP activation (vIRA), which inhibits RIP1/RIP3-mediated necroptosis. The M45 protein also blocks NF-κB activation by interacting with NEMO. When expressed by MCMV, MC159 blocked tumor necrosis factor alpha (TNF-α)-induced apoptosis of infected cells and partially restored MCMV replication in macrophages. However, MC159 did not fully replace M45, as it did not inhibit necroptosis in murine cells, but it reduced TNF-α-induced necroptosis in MCMV-infected human HT-29 cells. MC159 also differed from M45 in its effect on NF-κB. While MCMV-encoded M45 blocked NF-κB activation by TNF-α and interleukin-1β (IL-1β), MC159 inhibited TNF-α- but not IL-1β-induced NF-κB activation in infected mouse fibroblasts. These results indicate that the spectrum of MC159's functions differs depending on cell type and expression system and that a cell culture system for the propagation of MCV is needed to determine the biological relevance of presumed viral gene functions. IMPORTANCE MCV is a human-pathogenic poxvirus that cannot be propagated in cell culture or laboratory animals. Therefore, MCV gene products have been studied predominantly in cells expressing individual viral genes. In this study, we analyzed the function of the MCV gene MC159 by expressing it from a different virus and comparing its functions to those of two well-characterized MCMV genes. In this system, MC159 displayed some but not all of the previously described functions, suggesting that the functions of a viral gene depend on the conditions under which it is expressed. Until a cell culture system for the analysis of MCV becomes available, it might be necessary to analyze MCV genes in several different systems to extrapolate their biological importance.
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Gaidos G, Panaitiu AE, Guo B, Pellegrini M, Mierke DF. Identification and Characterization of the Interaction Site between cFLIPL and Calmodulin. PLoS One 2015; 10:e0141692. [PMID: 26529318 PMCID: PMC4631386 DOI: 10.1371/journal.pone.0141692] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 10/11/2015] [Indexed: 11/18/2022] Open
Abstract
Overexpression of the cellular FLICE-like inhibitory protein (cFLIP) has been reported in a number of tumor types. As an inactive procaspase-8 homologue, cFLIP is recruited to the intracellular assembly known as the Death Inducing Signaling Complex (DISC) where it inhibits apoptosis, leading to cancer cell proliferation. Here we characterize the molecular details of the interaction between cFLIPL and calmodulin, a ubiquitous calcium sensing protein. By expressing the individual domains of cFLIPL, we demonstrate that the interaction with calmodulin is mediated by the N-terminal death effector domain (DED1) of cFLIPL. Additionally, we mapped the interaction to a specific region of the C-terminus of DED1, referred to as DED1 R4. By designing DED1/DED2 chimeric constructs in which the homologous R4 regions of the two domains were swapped, calmodulin binding properties were transferred to DED2 and removed from DED1. Furthermore, we show that the isolated DED1 R4 peptide binds to calmodulin and solve the structure of the peptide-protein complex using NMR and computational refinement. Finally, we demonstrate an interaction between cFLIPL and calmodulin in cancer cell lysates. In summary, our data implicate calmodulin as a potential player in DISC-mediated apoptosis and provide evidence for a specific interaction with the DED1 of cFLIPL.
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Affiliation(s)
- Gabriel Gaidos
- Chemistry Department, Dartmouth College, Hanover, NH, United States of America
| | | | - Bingqian Guo
- Chemistry Department, Dartmouth College, Hanover, NH, United States of America
| | - Maria Pellegrini
- Chemistry Department, Dartmouth College, Hanover, NH, United States of America
| | - Dale F. Mierke
- Chemistry Department, Dartmouth College, Hanover, NH, United States of America
- * E-mail:
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Molecular architecture of the DED chains at the DISC: regulation of procaspase-8 activation by short DED proteins c-FLIP and procaspase-8 prodomain. Cell Death Differ 2015; 23:681-94. [PMID: 26494467 DOI: 10.1038/cdd.2015.137] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 07/30/2015] [Accepted: 08/03/2015] [Indexed: 12/17/2022] Open
Abstract
The CD95/Fas/APO-1 death-inducing signaling complex (DISC), comprising CD95, FADD, procaspase-8, procaspase-10, and c-FLIP, has a key role in apoptosis induction. Recently, it was demonstrated that procaspase-8 activation is driven by death effector domain (DED) chains at the DISC. Here, we analyzed the molecular architecture of the chains and the role of the short DED proteins in regulating procaspase-8 activation in the chain model. We demonstrate that the DED chains are largely composed of procaspase-8 cleavage products and, in particular, of its prodomain. The DED chain also comprises c-FLIP and procaspase-10 that are present in 10 times lower amounts compared with procaspase-8. We show that short c-FLIP isoforms can inhibit CD95-induced cell death upon overexpression, likely by forming inactive heterodimers with procaspase-8. Furthermore, we have addressed mechanisms of the termination of chain elongation using experimental and mathematical modeling approaches. We show that neither c-FLIP nor procaspase-8 prodomain terminates the DED chain, but rather the dissociation/association rates of procaspase-8 define the stability of the chain and thereby its length. In addition, we provide evidence that procaspase-8 prodomain generated at the DISC constitutes a negative feedback loop in procaspase-8 activation. Overall, these findings provide new insights into caspase-8 activation in DED chains and apoptosis initiation.
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38
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Vajjhala PR, Lu A, Brown DL, Pang SW, Sagulenko V, Sester DP, Cridland SO, Hill JM, Schroder K, Stow JL, Wu H, Stacey KJ. The Inflammasome Adaptor ASC Induces Procaspase-8 Death Effector Domain Filaments. J Biol Chem 2015; 290:29217-30. [PMID: 26468282 DOI: 10.1074/jbc.m115.687731] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Indexed: 01/19/2023] Open
Abstract
Inflammasomes mediate inflammatory and cell death responses to pathogens and cellular stress signals via activation of procaspases-1 and -8. During inflammasome assembly, activated receptors of the NLR or PYHIN family recruit the adaptor protein ASC and initiate polymerization of its pyrin domain (PYD) into filaments. We show that ASC filaments in turn nucleate procaspase-8 death effector domain (DED) filaments in vitro and in vivo. Interaction between ASC PYD and procaspase-8 tandem DEDs optimally required both DEDs and represents an unusual heterotypic interaction between domains of the death fold superfamily. Analysis of ASC PYD mutants showed that interaction surfaces that mediate procaspase-8 interaction overlap with those required for ASC self-association and interaction with the PYDs of inflammasome initiators. Our data indicate that multiple types of death fold domain filaments form at inflammasomes and that PYD/DED and homotypic PYD interaction modes are similar. Interestingly, we observed condensation of procaspase-8 filaments containing the catalytic domain, suggesting that procaspase-8 interactions within and/or between filaments may be involved in caspase-8 activation. Procaspase-8 filaments may also be relevant to apoptosis induced by death receptors.
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Affiliation(s)
| | - Alvin Lu
- the Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, and the Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, Massachusetts 02115
| | - Darren L Brown
- the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Siew Wai Pang
- From the School of Chemistry and Molecular Biosciences and
| | | | - David P Sester
- From the School of Chemistry and Molecular Biosciences and
| | | | - Justine M Hill
- From the School of Chemistry and Molecular Biosciences and
| | - Kate Schroder
- the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jennifer L Stow
- the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Hao Wu
- the Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, and the Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, Massachusetts 02115
| | - Katryn J Stacey
- From the School of Chemistry and Molecular Biosciences and the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia,
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Singh N, Hassan A, Bose K. Molecular basis of death effector domain chain assembly and its role in caspase-8 activation. FASEB J 2015; 30:186-200. [PMID: 26370846 DOI: 10.1096/fj.15-272997] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 08/31/2015] [Indexed: 12/20/2022]
Abstract
Assembly of a death-inducing signaling complex is a key event in the extrinsic apoptotic pathway, enabling activation of the caspase cascade and subsequent cell death. However, the molecular events governing DISC assembly have remained largely elusive because of the lack of information on mechanism and specificity regulating the death effector domain (DED)-DED interaction network. Using molecular modeling, mutagenesis, and biochemical and ex vivo experiments, we identified the precise binding interface and hot spots crucial for intermolecular DED chain assembly. Mutation of key interface residues (Leu42/Phe45) in procaspase-8 DED-A completely abrogated DED chain formation in HEK293 cells and prevented its association with FADD. A significant 2.6-3.6-fold reduction in procaspase-8 activation was observed in functional cell-death assays after substitution of the interfacial residues. Based on our results we propose a new model for DISC formation that refines the current understanding of the activation mechanism. Upon stimulation, FADD self-associates weakly via reciprocal interaction between helices α1/α4 and α2/α3 of the DED to form an oligomeric signaling platform that provides a stage for the initial recruitment of procaspase-8 through direct interaction with α1/α4 of DED-A, followed by sequential interaction mediated by helices α2/α5 of DED-B, to form the procaspase-8 DED chain that is crucial for its activation and subsequent cell death.
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Affiliation(s)
- Nitu Singh
- Integrated Biophysics and Structural Biology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Navi Mumbai, India
| | - Ali Hassan
- Integrated Biophysics and Structural Biology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Navi Mumbai, India
| | - Kakoli Bose
- Integrated Biophysics and Structural Biology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Navi Mumbai, India
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40
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Abstract
The PYRIN domain (PYD) is a protein-protein interaction domain, which belongs to the death domain fold (DDF) superfamily. It is best known for its signaling function in innate immune responses and particularly in the assembly of inflammasomes, which are large protein complexes that allow the induced proximity-mediated activation of caspase-1 and subsequently the release of pro-inflammatory cytokines. The molecular mechanism of inflammasome assembly was only recently elucidated and specifically requires PYD oligomerization. Here we discuss the recent advances in our understanding of PYD signaling and its regulation by PYD-only proteins.
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41
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Abstract
Death-inducing signaling complex (DISC) is a platform for the activation of initiator caspase in extrinsic apoptosis. Assembly of DISC is accomplished by two different types of homotypic interaction: one is between death domains (DDs) of a death receptor and FADD, and the other is between death effecter domains (DEDs) of FADD, procaspase-8/-10 and cFLIP. Recent biochemical investigations on the stoichiometry of DISC have revealed that single-DED-containing FADD exists in DISC in a substantially lower abundance than the sum of tandem-DEDs-containing components that are procaspase-8 and cFLIP. In addition, the homology models of the tandem DEDs in procaspase-8 and cFLIP show that two different interaction faces, H1-H4 face and H2-H5 face, are exposed for possible inter-molecular DED-DED interactions. These recent findings led to a proposal of the DED chain model for the interactions between FADD, procaspase-8 and cFLIP in DISC. This emerging view provides new insights on the topology of DED-DED network in DISC and furthermore on how procaspase-8 and cFLIP cluster for dimerization and proteolytic activation.
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Affiliation(s)
- Jin Kuk Yang
- Department of Chemistry, School of Natural Sciences, Soongsil University, Seoul, 156-743, Korea,
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42
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Abstract
The tumor necrosis factor receptors (TNFRs) play essential roles in innate and adaptive immunity. Depending on conditions, TNFR induces multiple cell fates including cell survival, cell apoptosis, and cell programmed necrosis. Here, we review recent progress in structural studies of the TNFR signaling pathway. The structural basis for the high order signal complexes, including the DISC, ripoptosome, necrosome, and RIP3/MLKL complex, may provide novel insights for understanding the biophysical principles of cell signaling cascades.
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43
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DED or alive: assembly and regulation of the death effector domain complexes. Cell Death Dis 2015; 6:e1866. [PMID: 26313917 PMCID: PMC4558505 DOI: 10.1038/cddis.2015.213] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 05/29/2015] [Accepted: 06/03/2015] [Indexed: 12/21/2022]
Abstract
Death effector domains (DEDs) are protein–protein interaction domains initially identified in proteins such as FADD, FLIP and caspase-8 involved in regulating apoptosis. Subsequently, these proteins have been shown to have important roles in regulating other forms of cell death, including necroptosis, and in regulating other important cellular processes, including autophagy and inflammation. Moreover, these proteins also have prominent roles in innate and adaptive immunity and during embryonic development. In this article, we review the various roles of DED-containing proteins and discuss recent developments in our understanding of DED complex formation and regulation. We also briefly discuss opportunities to therapeutically target DED complex formation in diseases such as cancer.
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44
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On the Quest of Cellular Functions of PEA-15 and the Therapeutic Opportunities. Pharmaceuticals (Basel) 2015; 8:455-73. [PMID: 26263999 PMCID: PMC4588177 DOI: 10.3390/ph8030455] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 07/18/2015] [Accepted: 07/24/2015] [Indexed: 02/03/2023] Open
Abstract
Phosphoprotein enriched in astrocytes, 15 KDa (PEA-15), a ubiquitously expressed small protein in all mammals, is known for decades for its potent interactions with various protein partners along distinct biological pathways. Most notable interacting partners of PEA-15 include extracellular signal-regulated kinase 1 and 2 (ERK1/2) in the mitogen activated protein kinase (MAPK) pathway, the Fas-associated death domain (FADD) protein involving in the formation of the death-inducing signaling complex (DISC), and the phospholipase D1 (PLD1) affecting the insulin sensitivity. However, the actual cellular functions of PEA-15 are still mysterious, and the question why this protein is expressed in almost all cell and tissue types remains unanswered. Here we synthesize the most recent structural, biological, and clinical studies on PEA-15 with emphases on its anti-apoptotic, anti-proliferative, and anti-inflammative properties, and propose a converged protective role of PEA-15 that maintains the balance of death and survival in different cell types. Under conditions that this delicate balance is unsustainable, PEA-15 may become pathological and lead to various diseases, including cancers and diabetes. Targeting PEA-15 interactions, or the use of PEA-15 protein as therapeutics, may provide a wider window of opportunities to treat these diseases.
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45
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Shen C, Yue H, Pei J, Guo X, Wang T, Quan JM. Crystal structure of the death effector domains of caspase-8. Biochem Biophys Res Commun 2015; 463:297-302. [PMID: 26003730 DOI: 10.1016/j.bbrc.2015.05.054] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 05/11/2015] [Indexed: 01/28/2023]
Abstract
Caspase-8 is a key mediator in various biological processes such as apoptosis, necroptosis, inflammation, T/B cells activation, and cell motility. Caspase-8 is characterized by the N-terminal tandem death effector domains (DEDs) and the C-terminal catalytic protease domain. The DEDs mediate diverse functions of caspase-8 through homotypic interactions of the DEDs between caspase-8 and its partner proteins. Here, we report the first crystal structure of the DEDs of caspase-8. The overall structure of the DEDs of caspase-8 is similar to that of the DEDs of vFLIP MC159, which is composed of two tandem death effector domains that closely associate with each other in a head-to-tail manner. Structural analysis reveals distinct differences in the region connecting helices α2b and α4b in the second DED of the DEDs between caspase-8 and MC159, in which the helix α3b in MC159 is replaced by a loop in caspase-8. Moreover, the different amino acids in this region might confer the distinct features of solubility and aggregation for the DEDs of caspase-8 and MC159.
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Affiliation(s)
- Chen Shen
- Key Laboratory of Structural Biology, School of Chemical Biology & Biotechnology, Peking University, Shenzhen Graduate School, Shenzhen 518055, China
| | - Hong Yue
- Key Laboratory of Structural Biology, School of Chemical Biology & Biotechnology, Peking University, Shenzhen Graduate School, Shenzhen 518055, China
| | - Jianwen Pei
- Key Laboratory of Structural Biology, School of Chemical Biology & Biotechnology, Peking University, Shenzhen Graduate School, Shenzhen 518055, China
| | - Xiaomin Guo
- Key Laboratory of Structural Biology, School of Chemical Biology & Biotechnology, Peking University, Shenzhen Graduate School, Shenzhen 518055, China
| | - Tao Wang
- Laboratory for Computational Chemistry & Drug Design, School of Chemical Biology & Biotechnology, Peking University, Shenzhen Graduate School, Shenzhen 518055, China.
| | - Jun-Min Quan
- Key Laboratory of Structural Biology, School of Chemical Biology & Biotechnology, Peking University, Shenzhen Graduate School, Shenzhen 518055, China.
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46
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Choi JY, Kim CM, Seo EK, Bhat EA, Jang TH, Lee JH, Park HH. Crystal structure of human POP1 and its distinct structural feature for PYD domain. Biochem Biophys Res Commun 2015; 460:957-63. [PMID: 25839653 DOI: 10.1016/j.bbrc.2015.03.134] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 03/24/2015] [Indexed: 01/20/2023]
Abstract
Inflammatory caspases, such as caspase-1, which is critical for the innate immune response, are activated upon the formation of a molecular complex called the inflammasome. The inflammasome is composed of three proteins, the Nod-like receptor (NLRP, NLRC or AIM2), apoptosis associated speck-loke protein containing a caspase-recruitment domain (ASC), and caspase-1. ASC is an adaptor molecule that contains an N-terminal PYD domain and a C-terminal CARD domain for interaction with other proteins. Upon activation, the N-terminal PYD of ASC homotypically interacts with the PYD domain of the Nod-like receptor, while its C-terminal CARD homotypically interacts with the CARD domain of caspase-1. PYD only protein 1 (POP1) negatively regulates inflammatory response by blocking the formation of the inflammasome. POP1 directly binds to ASC via a PYD:PYD interaction, thereby preventing ASC recruitment to Nod-like receptor NLRPs. POP1-mediated regulation of inflammation is of great biological importance. Here, we report the crystal structure of human POP1 and speculate about the inhibitory mechanism of POP1-mediated inflammasome formation based on the current structure.
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Affiliation(s)
- Jae Young Choi
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan 712-749, South Korea
| | - Chang Min Kim
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan 712-749, South Korea
| | - Eun Kyung Seo
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan 712-749, South Korea
| | - Eijaz Ahmed Bhat
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan 712-749, South Korea
| | - Tae-Ho Jang
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan 712-749, South Korea
| | - Jun Hyuck Lee
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon 406-840, Republic of Korea; Department of Polar Sciences, Korea University of Science and Technology, Incheon 406-840, Republic of Korea
| | - Hyun Ho Park
- School of Biotechnology and Graduate School of Biochemistry at Yeungnam University, Gyeongsan 712-749, South Korea.
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Tardif K, Hertig V, Duquette N, Villeneuve L, El-Hamamsy I, Tanguay JF, Calderone A. Nestin upregulation characterizes vascular remodeling secondary to hypertension in the rat. Am J Physiol Heart Circ Physiol 2015; 308:H1265-74. [PMID: 25770244 DOI: 10.1152/ajpheart.00804.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/03/2015] [Indexed: 11/22/2022]
Abstract
Proliferation and hypertrophy of vascular smooth muscle cells represent hallmark features of vessel remodeling secondary to hypertension. The intermediate filament protein nestin was recently identified in vascular smooth muscle cells and in other cell types directly participated in proliferation. The present study tested the hypothesis that vessel remodeling secondary to hypertension was characterized by nestin upregulation in vascular smooth muscle cells. Two weeks after suprarenal abdominal aorta constriction of adult male Sprague-Dawley rats, elevated mean arterial pressure increased the media area and thickness of the carotid artery and aorta and concomitantly upregulated nestin protein levels. In the normal adult rat carotid artery, nestin immunoreactivity was observed in a subpopulation of vascular smooth muscle cells, and the density significantly increased following suprarenal abdominal aorta constriction. Filamentous nestin was detected in cultured rat carotid artery- and aorta-derived vascular smooth muscle cells and an analogous paradigm observed in human aorta-derived vascular smooth muscle cells. ANG II and EGF treatment of vascular smooth muscle cells stimulated DNA and protein synthesis and increased nestin protein levels. Lentiviral short-hairpin RNA-mediated nestin depletion of carotid artery-derived vascular smooth muscle cells inhibited peptide growth factor-stimulated DNA synthesis, whereas protein synthesis remained intact. These data have demonstrated that vessel remodeling secondary to hypertension was characterized in part by nestin upregulation in vascular smooth muscle cells. The selective role of nestin in peptide growth factor-stimulated DNA synthesis has revealed that the proliferative and hypertrophic responses of vascular smooth muscle cells were mediated by divergent signaling events.
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Affiliation(s)
- Kim Tardif
- Program in Biomedical Sciences, Université de Montréal, Montréal, Québec, Canada; Research Center, Montreal Heart Institute and Université de Montréal, Montréal, Québec, Canada
| | - Vanessa Hertig
- Departement of Physiology, Université de Montréal, Montréal, Québec, Canada; and Research Center, Montreal Heart Institute and Université de Montréal, Montréal, Québec, Canada
| | - Natacha Duquette
- Research Center, Montreal Heart Institute and Université de Montréal, Montréal, Québec, Canada
| | - Louis Villeneuve
- Research Center, Montreal Heart Institute and Université de Montréal, Montréal, Québec, Canada
| | - Ismail El-Hamamsy
- Research Center, Montreal Heart Institute and Université de Montréal, Montréal, Québec, Canada
| | - Jean-François Tanguay
- Program in Biomedical Sciences, Université de Montréal, Montréal, Québec, Canada; Research Center, Montreal Heart Institute and Université de Montréal, Montréal, Québec, Canada
| | - Angelino Calderone
- Departement of Physiology, Université de Montréal, Montréal, Québec, Canada; and Research Center, Montreal Heart Institute and Université de Montréal, Montréal, Québec, Canada
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48
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Abstract
Molluscum contagiosum virus (MCV) is the causative agent of molluscum contagiosum (MC), the third most common viral skin infection in children, and one of the five most prevalent skin diseases worldwide. No FDA-approved treatments, vaccines, or commercially available rapid diagnostics for MCV are available. This review discusses several aspects of this medically important virus including: physical properties of MCV, MCV pathogenesis, MCV replication, and immune responses to MCV infection. Sequencing of the MCV genome revealed novel immune evasion molecules which are highlighted here. Special attention is given to the MCV MC159 and MC160 proteins. These proteins are FLIPs with homologs in gamma herpesviruses and in the cell. They are of great interest because each protein regulates apoptosis, NF-κB, and IRF3. However, the mechanism that each protein uses to impart its effects is different. It is important to elucidate how MCV inhibits immune responses; this knowledge contributes to our understanding of viral pathogenesis and also provides new insights into how the immune system neutralizes virus infections.
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49
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Parsons MJ, Bouchier-Hayes L. Measuring initiator caspase activation by bimolecular fluorescence complementation. Cold Spring Harb Protoc 2015; 2015:pdb.prot082552. [PMID: 25561623 DOI: 10.1101/pdb.prot082552] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Initiator caspases, including caspase-2, -8, and -9, are activated by the proximity-driven dimerization that occurs after their recruitment to activation platforms. Here we describe the use of caspase bimolecular fluorescence complementation (caspase BiFC) to measure this induced proximity. BiFC assays rely on the use of a split fluorescent protein to identify protein-protein interactions in cells. When fused to interacting proteins, the fragments of the split fluorescent protein (which do not fluoresce on their own) can associate and fluoresce. In this protocol, we use the fluorescent protein Venus, a brighter and more photostable variant of yellow fluorescent protein (YFP), to detect the induced proximity of caspase-2. Plasmids encoding two fusion products (caspase-2 fused to either the amino- or carboxy-terminal halves of Venus) are transfected into cells. The cells are then treated with an activating (death) stimulus. The induced proximity (and subsequent activation) of caspase-2 in the cells is visualized as Venus fluorescence. The proportion of Venus-positive cells at a single time point can be determined using fluorescence microscopy. Alternatively, the increase in fluorescence intensity over time can be evaluated by time-lapse confocal microscopy. The caspase BiFC strategy described here should also work for other initiator caspases, such as caspase-8 or -9, as long as the correct controls are used.
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Affiliation(s)
- Melissa J Parsons
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, Texas 77030 Department of Pediatrics-Hematology, Baylor College of Medicine, Houston, Texas 77030
| | - Lisa Bouchier-Hayes
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, Texas 77030 Department of Pediatrics-Hematology, Baylor College of Medicine, Houston, Texas 77030
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50
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Abstract
Cellular FLICE-inhibitory protein (cFLIP) is structurally related to caspase-8, but lacks its protease activity. Cflip gene encodes several splicing variants including short form (cFLIPs) and long form (cFLIPL). cFLIPL is composed of two death effector domains at the N terminus and a C-terminal caspase-like domain, and cFLIPs lacks the caspase-like domain. Our studies reveal that cFLIP plays a central role in NF-κB-dependent survival signals that control apoptosis and programmed necrosis. Germline deletion of Cflip results in embryonic lethality due to enhanced apoptosis and programmed necrosis; however, the combined deletion of the death-signaling regulators, Fadd and Ripk3, prevents embryonic lethality in Cflip-deficient mice. Moreover, tissue-specific deletion of Cflip reveals cFLIP as a crucial regulator that maintains tissue homeostasis of immune cells, hepatocytes, intestinal epithelial cells, and epidermal cells by preventing apoptosis and programmed necrosis.
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