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Li L, Wang J, Zhong X, Jiang Y, Pei G, Yang X, Zhang K, Shen S, Jin X, Sun G, Su C, Chen S, Yin H. ADP-Hep-Induced Liquid Phase Condensation of TIFA-TRAF6 Activates ALPK1/TIFA-Dependent Innate Immune Responses. RESEARCH (WASHINGTON, D.C.) 2024; 7:0315. [PMID: 38357697 PMCID: PMC10865109 DOI: 10.34133/research.0315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 01/19/2024] [Indexed: 02/16/2024]
Abstract
The ALPK1 (alpha-kinase 1)-TIFA (TRAF-interacting protein with fork head-associated domain)-TRAF6 signaling pathway plays a pivotal role in regulating inflammatory processes, with TIFA and TRAF6 serving as key molecules in this cascade. Despite its significance, the functional mechanism of TIFA-TRAF6 remains incompletely understood. In this study, we unveil that TIFA undergoes liquid-liquid phase separation (LLPS) induced by ALPK1 in response to adenosine diphosphate (ADP)-β-D-manno-heptose (ADP-Hep) recognition. The phase separation of TIFA is primarily driven by ALPK1, the pT9-FHA domain, and the intrinsically disordered region segment. Simultaneously, TRAF6 exhibits phase separation during ADP-Hep-induced inflammation, a phenomenon observed consistently across various inflammatory signal pathways. Moreover, TRAF6 is recruited within the TIFA condensates, facilitating lysine (K) 63-linked polyubiquitin chain synthesis. The subsequent recruitment, enrichment, and activation of downstream effectors within these condensates contribute to robust inflammatory signal transduction. Utilizing a novel chemical probe (compound 22), our analysis demonstrates that the activation of the ALPK1-TIFA-TRAF6 signaling pathway in response to small molecules necessitates the phase separation of TIFA. In summary, our findings reveal TIFA as a sensor for upstream signals, initiating the LLPS of itself and downstream proteins. This process results in the formation of membraneless condensates within the ALPK1-TIFA-TRAF6 pathway, suggesting potential applications in therapeutic biotechnology development.
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Affiliation(s)
- Liping Li
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
- Department of Cancer Research, Institute of Medicinal Biotechnology,
Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Jia Wang
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
- State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, College of Future Technology,
Peking University, Beijing, China
| | - Xincheng Zhong
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Yaoyao Jiang
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Gaofeng Pei
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
- School of Life Sciences,
Tsinghua University, Beijing, 100084, China
| | - Xikang Yang
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Kaixiang Zhang
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Siqi Shen
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Xue Jin
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Gaoge Sun
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Chaofei Su
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Shuzhen Chen
- Department of Cancer Research, Institute of Medicinal Biotechnology,
Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Hang Yin
- State Key Laboratory of Membrane Biology, School of Pharmaceutical Sciences, Institute for Precision Medicine, Tsinghua-Peking Center for Life Sciences, Key Laboratory of Bioorganic Phosphorous chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
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Scrima N, Le Bars R, Nevers Q, Glon D, Chevreux G, Civas A, Blondel D, Lagaudrière-Gesbert C, Gaudin Y. Rabies virus P protein binds to TBK1 and interferes with the formation of innate immunity-related liquid condensates. Cell Rep 2023; 42:111949. [PMID: 36640307 DOI: 10.1016/j.celrep.2022.111949] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 07/27/2022] [Accepted: 12/19/2022] [Indexed: 01/06/2023] Open
Abstract
Viruses must overcome the interferon-mediated antiviral response to replicate and propagate into their host. Rabies virus (RABV) phosphoprotein P is known to inhibit interferon induction. Here, using a global mass spectrometry approach, we show that RABV P binds to TBK1, a kinase located at the crossroads of many interferon induction pathways, resulting in innate immunity inhibition. Mutations of TBK1 phosphorylation sites abolish P binding. Importantly, we demonstrate that upon RABV infection or detection of dsRNA by innate immunity sensors, TBK1 and its adaptor proteins NAP1 and SINTBAD form dynamic cytoplasmic condensates that have liquid properties. These condensates can form larger aggregates having ring-like structures in which NAP1 and TBK1 exhibit locally restricted movement. P binding to TBK1 interferes with the formation of these structures. This work demonstrates that proteins of the signaling pathway leading to interferon induction transiently form liquid organelles that can be targeted by viruses.
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Affiliation(s)
- Nathalie Scrima
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Romain Le Bars
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Quentin Nevers
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Damien Glon
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | | | - Ahmet Civas
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Danielle Blondel
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Cécile Lagaudrière-Gesbert
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France.
| | - Yves Gaudin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette, France.
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Zou L, Liao M, Zhen Y, Zhu S, Chen X, Zhang J, Hao Y, Liu B. Autophagy and beyond: Unraveling the complexity of UNC-51-like kinase 1 (ULK1) from biological functions to therapeutic implications. Acta Pharm Sin B 2022; 12:3743-3782. [PMID: 36213540 PMCID: PMC9532564 DOI: 10.1016/j.apsb.2022.06.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 05/27/2022] [Accepted: 06/02/2022] [Indexed: 12/13/2022] Open
Abstract
UNC-51-like kinase 1 (ULK1), as a serine/threonine kinase, is an autophagic initiator in mammals and a homologous protein of autophagy related protein (Atg) 1 in yeast and of UNC-51 in Caenorhabditis elegans. ULK1 is well-known for autophagy activation, which is evolutionarily conserved in protein transport and indispensable to maintain cell homeostasis. As the direct target of energy and nutrition-sensing kinase, ULK1 may contribute to the distribution and utilization of cellular resources in response to metabolism and is closely associated with multiple pathophysiological processes. Moreover, ULK1 has been widely reported to play a crucial role in human diseases, including cancer, neurodegenerative diseases, cardiovascular disease, and infections, and subsequently targeted small-molecule inhibitors or activators are also demonstrated. Interestingly, the non-autophagy function of ULK1 has been emerging, indicating that non-autophagy-relevant ULK1 signaling network is also linked with diseases under some specific contexts. Therefore, in this review, we summarized the structure and functions of ULK1 as an autophagic initiator, with a focus on some new approaches, and further elucidated the key roles of ULK1 in autophagy and non-autophagy. Additionally, we also discussed the relationships between ULK1 and human diseases, as well as illustrated a rapid progress for better understanding of the discovery of more candidate small-molecule drugs targeting ULK1, which will provide a clue on novel ULK1-targeted therapeutics in the future.
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Affiliation(s)
- Ling Zou
- School of Pharmaceutical Sciences, Health Science Center, Shenzhen University, Shenzhen 518060, China
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Minru Liao
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yongqi Zhen
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Shiou Zhu
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Xiya Chen
- School of Pharmaceutical Sciences, Health Science Center, Shenzhen University, Shenzhen 518060, China
| | - Jin Zhang
- School of Pharmaceutical Sciences, Health Science Center, Shenzhen University, Shenzhen 518060, China
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
- Corresponding authors. Tel./fax: +86 28 85503817.
| | - Yue Hao
- School of Pharmaceutical Sciences, Health Science Center, Shenzhen University, Shenzhen 518060, China
- Corresponding authors. Tel./fax: +86 28 85503817.
| | - Bo Liu
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
- Corresponding authors. Tel./fax: +86 28 85503817.
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TRAF6 Phosphorylation Prevents Its Autophagic Degradation and Re-Shapes LPS-Triggered Signaling Networks. Cancers (Basel) 2021; 13:cancers13143618. [PMID: 34298830 PMCID: PMC8303406 DOI: 10.3390/cancers13143618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/07/2021] [Accepted: 07/13/2021] [Indexed: 11/20/2022] Open
Abstract
Simple Summary Here, we reveal that basal turnover and autophagy-induced decay of the ubiquitin E3 ligase TRAF6 is antagonized by IKKε-mediated phosphorylation at five serines. Phosphoproteomic experiments show that TRAF6 and its phosphorylation contribute to the remodeling of LPS- and autophagyinduced signaling networks, revealing an intricate link between inflammatory and metabolic processes that are frequently dysregulated in cancer. Abstract The ubiquitin E3 ligase TNF Receptor Associated Factor 6 (TRAF6) participates in a large number of different biological processes including innate immunity, differentiation and cell survival, raising the need to specify and shape the signaling output. Here, we identify a lipopolysaccharide (LPS)-dependent increase in TRAF6 association with the kinase IKKε (inhibitor of NF-κB kinase subunit ε) and IKKε-mediated TRAF6 phosphorylation at five residues. The reconstitution of TRAF6-deficient cells, with TRAF6 mutants representing phosphorylation-defective or phospho-mimetic TRAF6 variants, showed that the phospho-mimetic TRAF6 variant was largely protected from basal ubiquitin/proteasome-mediated degradation, and also from autophagy-mediated decay in autolysosomes induced by metabolic perturbation. In addition, phosphorylation of TRAF6 and its E3 ligase function differentially shape basal and LPS-triggered signaling networks, as revealed by phosphoproteome analysis. Changes in LPS-triggered phosphorylation networks of cells that had experienced autophagy are partially dependent on TRAF6 and its phosphorylation status, suggesting an involvement of this E3 ligase in the interplay between metabolic and inflammatory circuits.
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FIP200 controls the TBK1 activation threshold at SQSTM1/p62-positive condensates. Sci Rep 2021; 11:13863. [PMID: 34226595 PMCID: PMC8257712 DOI: 10.1038/s41598-021-92408-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 06/07/2021] [Indexed: 12/17/2022] Open
Abstract
The protein kinase TBK1 is a central regulator of innate immune responses and autophagy, and ablation of either function has been linked to neuroinflammatory or degenerative diseases. Autophagy is an intracellular process that recycles old or damaged proteins and organelles. In recent years, the TBK1-dependent regulation of autophagy pathways has been characterized. However, the autophagy-dependent regulation of TBK1 activity awaits further clarification. Here, we observed that TBK1 is recruited to SQSTM1/p62-containing aggregates via the selective autophagy receptor TAX1BP1. In these aggregates, TBK1 phosphorylates SQSTM1/p62 at serine 403 and thus presumably regulates the efficient engulfment and clearance of these structures. We found that TBK1 activation is strongly increased if FIP200, a component of the autophagy-inducing ULK1 complex, is not present or cannot bind to TAX1BP1. Given our collective findings, we hypothesize that FIP200 ensures the inducible activation of TBK1 at SQSTM1/p62 condensates.
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Mohamud Y, Xue YC, Liu H, Ng CS, Bahreyni A, Jan E, Luo H. The papain-like protease of coronaviruses cleaves ULK1 to disrupt host autophagy. Biochem Biophys Res Commun 2021; 540:75-82. [PMID: 33450483 PMCID: PMC7836930 DOI: 10.1016/j.bbrc.2020.12.091] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 12/25/2020] [Indexed: 01/27/2023]
Abstract
The ongoing pandemic of COVID-19 alongside the outbreaks of SARS in 2003 and MERS in 2012 underscore the significance to understand betacoronaviruses as a global health challenge. SARS-CoV-2, the etiological agent for COVID-19, has infected over 50 million individuals' worldwide with more than ∼1 million fatalities. Autophagy modulators have emerged as potential therapeutic candidates against SARS-CoV-2 but recent clinical setbacks urge for better understanding of viral subversion of autophagy. Using MHV-A59 as a model betacoronavirus, time-course infections revealed significant loss in the protein level of ULK1, a canonical autophagy-regulating kinase, and the concomitant appearance of a possible cleavage fragment. To investigate whether virus-encoded proteases target ULK1, we conducted in-vitro and cellular cleavage assays and identified ULK1 as a novel bona fide substrate of SARS-CoV-2 papain-like protease (PLpro). Mutagenesis studies discovered that ULK1 is cleaved at a conserved PLpro recognition sequence (LGGG) after G499, separating its N-terminal kinase domain from a C-terminal substrate recognition region. Over-expression of SARS-CoV-2 PLpro is sufficient to impair starvation-induced autophagy and disrupt formation of ULK1-ATG13 complex. Finally, we demonstrated a dual role for ULK1 in MHV-A59 replication, serving a pro-viral functions during early replication that is inactivated at late stages of infection. In conclusion, our study identified a new mechanism by which PLpro of betacoronaviruses induces viral pathogenesis by targeting cellular autophagy.
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Affiliation(s)
- Yasir Mohamud
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, Canada; Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Yuan Chao Xue
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, Canada; Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Huitao Liu
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, Canada; Experimental Medicine, University of British Columbia, Vancouver, Canada
| | - Chen Seng Ng
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, Canada; Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Amirhossein Bahreyni
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, Canada; Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Eric Jan
- Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
| | - Honglin Luo
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, Canada; Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada.
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7
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Haas J, Bloesel D, Bacher S, Kracht M, Schmitz ML. Chromatin Targeting of HIPK2 Leads to Acetylation-Dependent Chromatin Decondensation. Front Cell Dev Biol 2020; 8:852. [PMID: 32984337 PMCID: PMC7490299 DOI: 10.3389/fcell.2020.00852] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 08/10/2020] [Indexed: 11/13/2022] Open
Abstract
The protein kinase homeodomain-interacting protein kinase 2 (HIPK2) plays an important role in development and in the response to external cues. The kinase associates with an exceptionally large number of different transcription factors and chromatin regulatory proteins to direct distinct gene expression programs. In order to investigate the function of HIPK2 for chromatin compaction, HIPK2 was fused to the DNA-binding domains of Gal4 or LacI, thus allowing its specific targeting to binding sites for these transcription factors that were integrated in specific chromosome loci. Tethering of HIPK2 resulted in strong decompaction of euchromatic and heterochromatic areas. HIPK2-mediated heterochromatin decondensation started already 4 h after its chromatin association and required the functionality of its SUMO-interacting motif. This process was paralleled by disappearance of the repressive H3K27me3 chromatin mark, recruitment of the acetyltransferases CBP and p300 and increased histone acetylation at H3K18 and H4K5. HIPK2-mediated chromatin decompaction was strongly inhibited in the presence of a CBP/p300 inhibitor and completely blocked by the BET inhibitor JQ1, consistent with a causative role of acetylations for this process. Chromatin tethering of HIPK2 had only a minor effect on basal transcription, while it strongly boosted estrogen-triggered gene expression by acting as a transcriptional cofactor.
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Affiliation(s)
- Jana Haas
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
| | - Daniel Bloesel
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
| | - Susanne Bacher
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
| | - Michael Kracht
- Member of the German Center for Lung Research, Giessen, Germany.,Rudolf-Buchheim-Institute of Pharmacology, Justus-Liebig-University, Giessen, Germany
| | - M Lienhard Schmitz
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
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Yeo SK, Wang C, Guan JL. Role of FIP200 in inflammatory processes beyond its canonical autophagy function. Biochem Soc Trans 2020; 48:1599-1607. [PMID: 32662824 DOI: 10.1042/bst20191156] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 06/19/2020] [Accepted: 06/23/2020] [Indexed: 12/17/2022]
Abstract
FIP200 (RB1CC1) is a critical regulator of canonical macroautophagy and has also emerged as a crucial regulator of selective autophagy as well as inflammatory processes. The illumination of FIP200's role in autophagy at the molecular level has been accompanied by studies demonstrating the importance of its autophagy function in physiological processes in mammals and pathological contexts such as cancer. However, there is an increasing appreciation that most, if not all of the autophagy genes, also play a role in other processes such as LC3-associated phagocytosis, vesicle trafficking and protein secretion. Consequently, this has led to efforts in generating specific mutants of autophagy genes that are more amenable to dissecting their autophagy versus non-autophagy functions. In this aspect, we have generated a FIP200 knock-in mouse allele that is defective for canonical macroautophagy. This has revealed a canonical-autophagy-independent function of FIP200 that is responsible for limiting pro-inflammatory signaling. In this review, we will discuss FIP200's role in this process, the implications with regards to cancer immunotherapy and highlight key prospective avenues to specifically dissect the distinct functions of FIP200.
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Affiliation(s)
- Syn Kok Yeo
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, U.S.A
| | - Chenran Wang
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, U.S.A
| | - Jun-Lin Guan
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, U.S.A
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Kracht M, Müller-Ladner U, Schmitz ML. Mutual regulation of metabolic processes and proinflammatory NF-κB signaling. J Allergy Clin Immunol 2020; 146:694-705. [PMID: 32771559 DOI: 10.1016/j.jaci.2020.07.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/16/2020] [Accepted: 07/28/2020] [Indexed: 12/27/2022]
Abstract
The nuclear factor kappa B (NF-κB) signaling system, a key regulator of immunologic processes, also affects a plethora of metabolic changes associated with inflammation and the immune response. NF-κB-regulating signaling cascades, in concert with NF-κB-mediated transcriptional events, control the metabolism at several levels. NF-κB modulates apical components of metabolic processes including metabolic hormones such as insulin and glucagon, the cellular master switches 5' AMP-activated protein kinase and mTOR, and also numerous metabolic enzymes and their respective regulators. Vice versa, metabolic enzymes and their products also exert multilevel control of NF-κB activity, thereby creating a highly connected regulatory network. These insights have resulted in the identification of the noncanonical IκB kinase kinases IκB kinase ɛ and TBK1, which are upregulated by overnutrition, and may therefore be suitable potential therapeutic targets for metabolic syndromes. An inhibitor interfering with the activity of both kinases reduces obesity-related metabolic dysfunctions in mouse models and the encouraging results from a recent clinical trial indicate that targeting these NF-κB pathway components improves glucose homeostasis in a subset of patients with type 2 diabetes.
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Affiliation(s)
- Michael Kracht
- Rudolf Buchheim-Institute of Pharmacology, Justus-Liebig-University, Giessen, Germany
| | - Ulf Müller-Ladner
- Department of Rheumatology and Clinical Immunology, Justus-Liebig-University, Campus Kerckhoff, Bad Nauheim, Germany
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