1
|
König T, McBride HM. Mitochondrial-derived vesicles in metabolism, disease, and aging. Cell Metab 2024; 36:21-35. [PMID: 38171335 DOI: 10.1016/j.cmet.2023.11.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/16/2023] [Accepted: 11/28/2023] [Indexed: 01/05/2024]
Abstract
Mitochondria are central hubs of cellular metabolism and are tightly connected to signaling pathways. The dynamic plasticity of mitochondria to fuse, divide, and contact other organelles to flux metabolites is central to their function. To ensure bona fide functionality and signaling interconnectivity, diverse molecular mechanisms evolved. An ancient and long-overlooked mechanism is the generation of mitochondrial-derived vesicles (MDVs) that shuttle selected mitochondrial cargoes to target organelles. Just recently, we gained significant insight into the mechanisms and functions of MDV transport, ranging from their role in mitochondrial quality control to immune signaling, thus demonstrating unexpected and diverse physiological aspects of MDV transport. This review highlights the origin of MDVs, their biogenesis, and their cargo selection, with a specific focus on the contribution of MDV transport to signaling across cell and organ barriers. Additionally, the implications of MDVs in peroxisome biogenesis, neurodegeneration, metabolism, aging, and cancer are discussed.
Collapse
Affiliation(s)
- Tim König
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Heidi M McBride
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
| |
Collapse
|
2
|
Hayashi Y, Takatori S, Warsame WY, Tomita T, Fujisawa T, Ichijo H. TOLLIP acts as a cargo adaptor to promote lysosomal degradation of aberrant ER membrane proteins. EMBO J 2023; 42:e114272. [PMID: 37929762 PMCID: PMC10690474 DOI: 10.15252/embj.2023114272] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 11/07/2023] Open
Abstract
Endoplasmic reticulum (ER) proteostasis is maintained by various catabolic pathways. Lysosomes clear entire ER portions by ER-phagy, while proteasomes selectively clear misfolded or surplus aberrant proteins by ER-associated degradation (ERAD). Recently, lysosomes have also been implicated in the selective clearance of aberrant ER proteins, but the molecular basis remains unclear. Here, we show that the phosphatidylinositol-3-phosphate (PI3P)-binding protein TOLLIP promotes selective lysosomal degradation of aberrant membrane proteins, including an artificial substrate and motoneuron disease-causing mutants of VAPB and Seipin. These cargos are recognized by TOLLIP through its misfolding-sensing intrinsically disordered region (IDR) and ubiquitin-binding CUE domain. In contrast to ER-phagy receptors, which clear both native and aberrant proteins by ER-phagy, TOLLIP selectively clears aberrant cargos by coupling them with the PI3P-dependent lysosomal trafficking without promoting bulk ER turnover. Moreover, TOLLIP depletion augments ER stress after ERAD inhibition, indicating that TOLLIP and ERAD cooperatively safeguard ER proteostasis. Our study identifies TOLLIP as a unique type of cargo-specific adaptor dedicated to the clearance of aberrant ER cargos and provides insights into molecular mechanisms underlying lysosome-mediated quality control of membrane proteins.
Collapse
Affiliation(s)
- Yuki Hayashi
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | - Sho Takatori
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | | | - Taisuke Tomita
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | - Takao Fujisawa
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | - Hidenori Ichijo
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| |
Collapse
|
3
|
Bejaoui Y, Alresheq S, Durand S, Vilaire-Meunier M, Maillebouis L, Zen AAH, Mégarbané A, Hajj NE. DNA methylation profiling in Trisomy 21 females with and without breast cancer. Front Oncol 2023; 13:1203483. [PMID: 37538118 PMCID: PMC10395079 DOI: 10.3389/fonc.2023.1203483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 07/03/2023] [Indexed: 08/05/2023] Open
Abstract
Background Down Syndrome (DS) is the most common chromosome anomaly in humans and occurs due to an extra copy of chromosome 21. The malignancy profile in DS is unique, since DS patients have a low risk of developing solid tumors such as breast cancer however they are at higher risk of developing acute myeloid leukemia and acute lymphoblastic leukemia. Methods In this study, we investigated DNA methylation signatures and epigenetic aging in DS individuals with and without breast cancer. We analyzed DNA methylation patterns in Trisomy 21 (T21) individuals without breast cancer (T21-BCF) and DS individuals with breast cancer (T21-BC), using the Infinium Methylation EPIC BeadChip array. Results Our results revealed several differentially methylated sites and regions in the T21-BC patients that were associated with changes in gene expression. The differentially methylated CpG sites were enriched for processes related to serine-type peptidase activity, epithelial cell development, GTPase activity, bicellular tight junction, Ras protein signal transduction, etc. On the other hand, the epigenetic age acceleration analysis showed no difference between T21-BC and T21-BCF patients. Conclusions This is the first study to investigate DNA methylation changes in Down syndrome women with and without breast cancer and it could help shed light on factors that protect against breast cancer in DS.
Collapse
Affiliation(s)
- Yosra Bejaoui
- College of Health and Life Sciences, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Sara Alresheq
- College of Health and Life Sciences, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | | | | | | | - Ayman Al Haj Zen
- College of Health and Life Sciences, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - André Mégarbané
- Institut Jérôme Lejeune, Paris, France
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Nady El Hajj
- College of Health and Life Sciences, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
- College of Science and Engineering, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| |
Collapse
|
4
|
von Mentzer U, Selldén T, Råberg L, Erensoy G, Hultgård Ekwall AK, Stubelius A. Synovial fluid profile dictates nanoparticle uptake into cartilage - implications of the protein corona for novel arthritis treatments. Osteoarthritis Cartilage 2022; 30:1356-1364. [PMID: 35840018 DOI: 10.1016/j.joca.2022.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 06/29/2022] [Accepted: 07/05/2022] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Drug delivery strategies for joint diseases need to overcome the negatively charged cartilage matrix. Previous studies have extensively investigated particle approaches to increase uptake efficiency by harnessing the anionic charge of the cartilage but have neglected to address potential interactions with the protein-rich biological environment of the joint space. We aimed to evaluate the effects of hard protein coronas derived from osteoarthritis (OA) and rheumatoid arthritis (RA) patient synovial fluids as well as the commonly used fetal calf serum (FCS) on nanoparticle (NP) uptake into tissues and cells. METHODS We developed a NP panel with varying PEGylation and incubated them with synovial fluid from either OA, RA patients or FCS. We evaluated the effects of the formed NP-biocorona complex uptake into the porcine articular cartilage explants, chondrocytes and monocyte cell lines and primary patient FLS cells. Proteins composing hard biocoronas were identified using a quantitative proteomics approach. RESULTS Formed biocoronas majorly impacted NP uptake into cartilage tissue and dictated their uptake in chondrocytes and monocytes. The most suitable NP for potential OA applications was identified. A variety of proteins that were found on all NPs, irrespective of surface modifications. NP-, and protein-specific differences were also observed between the groups, and candidate proteins were identified that could account for the observed differences. CONCLUSIONS This study demonstrates the impact of protein coronas from OA and RA patient synovial fluids on NP uptake into cartilage, emphasizing the importance of biological microenvironment considerations for successful translation of drug delivery vehicles into clinics.
Collapse
Affiliation(s)
- U von Mentzer
- Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - T Selldén
- Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - L Råberg
- Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - G Erensoy
- Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - A-K Hultgård Ekwall
- The Rheumatology Clinic, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - A Stubelius
- Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden.
| |
Collapse
|
5
|
Hernandez GA, Perera RM. Autophagy in cancer cell remodeling and quality control. Mol Cell 2022; 82:1514-1527. [PMID: 35452618 PMCID: PMC9119670 DOI: 10.1016/j.molcel.2022.03.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/01/2022] [Accepted: 03/17/2022] [Indexed: 12/12/2022]
Abstract
As one of the two highly conserved cellular degradation systems, autophagy plays a critical role in regulation of protein, lipid, and organelle quality control and cellular homeostasis. This evolutionarily conserved pathway singles out intracellular substrates for elimination via encapsulation within a double-membrane vesicle and delivery to the lysosome for degradation. Multiple cancers disrupt normal regulation of autophagy and hijack its degradative ability to remodel their proteome, reprogram their metabolism, and adapt to environmental challenges, making the autophagy-lysosome system a prime target for anti-cancer interventions. Here, we discuss the roles of autophagy in tumor progression, including cancer-specific mechanisms of autophagy regulation and the contribution of tumor and host autophagy in metabolic regulation, immune evasion, and malignancy. We further discuss emerging proteomics-based approaches for systematic profiling of autophagosome-lysosome composition and contents. Together, these approaches are uncovering new features and functions of autophagy, leading to more effective strategies for targeting this pathway in cancer.
Collapse
Affiliation(s)
- Grace A Hernandez
- Department of Anatomy, Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Rushika M Perera
- Department of Anatomy, Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA.
| |
Collapse
|
6
|
Monogenic autoimmunity and infectious diseases: the double-edged sword of immune dysregulation. Curr Opin Immunol 2021; 72:230-238. [PMID: 34265589 PMCID: PMC8452259 DOI: 10.1016/j.coi.2021.06.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 06/16/2021] [Accepted: 06/18/2021] [Indexed: 01/10/2023]
Abstract
The study of monogenic autoimmune diseases has provided key insights into molecular mechanisms involved in development of autoimmunity and immune tolerance. It has also become clear that such inborn errors of immunity (IEIs) frequently present clinically not only with autoimmune diseases, but also frequently have increased susceptibility to infection. The genes associated with monogenic autoimmunity influence diverse functional pathways, and the resulting immune dysregulation also impacts the complex and coordinated immune response to pathogens, for example type I interferon and cytokine signaling, the complement pathway and proper differentiation of the immune response. The SARS-CoV-2 pandemic has highlighted how monogenic autoimmunity can increase risk for serious infection with the discovery of severe disease in patients with pre-existing antibodies to Type I IFNs. This review discusses recent insight into the relationship between monogenic autoimmunity and infectious diseases.
Collapse
|
7
|
Roach TG, Lång HKM, Xiong W, Ryhänen SJ, Capelluto DGS. Protein Trafficking or Cell Signaling: A Dilemma for the Adaptor Protein TOM1. Front Cell Dev Biol 2021; 9:643769. [PMID: 33718385 PMCID: PMC7952518 DOI: 10.3389/fcell.2021.643769] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/09/2021] [Indexed: 12/29/2022] Open
Abstract
Lysosomal degradation of ubiquitinated transmembrane protein receptors (cargo) relies on the function of Endosomal Sorting Complex Required for Transport (ESCRT) protein complexes. The ESCRT machinery is comprised of five unique oligomeric complexes with distinct functions. Target of Myb1 (TOM1) is an ESCRT protein involved in the initial steps of endosomal cargo sorting. To exert its function, TOM1 associates with ubiquitin moieties on the cargo via its VHS and GAT domains. Several ESCRT proteins, including TOLLIP, Endofin, and Hrs, have been reported to form a complex with TOM1 at early endosomal membrane surfaces, which may potentiate the role of TOM1 in cargo sorting. More recently, it was found that TOM1 is involved in other physiological processes, including autophagy, immune responses, and neuroinflammation, which crosstalk with its endosomal cargo sorting function. Alteration of TOM1 function has emerged as a phosphoinositide-dependent survival mechanism for bacterial infections and cancer progression. Based on current knowledge of TOM1-dependent cellular processes, this review illustrates how TOM1 functions in coordination with an array of protein partners under physiological and pathological scenarios.
Collapse
Affiliation(s)
- Tiffany G. Roach
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States
| | - Heljä K. M. Lång
- Division of Hematology, Oncology, and Stem Cell Transplantation, Children’s Hospital, and Pediatric Research Center, The New Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
- Department of Anatomy and Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Wen Xiong
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States
| | - Samppa J. Ryhänen
- Division of Hematology, Oncology, and Stem Cell Transplantation, Children’s Hospital, and Pediatric Research Center, The New Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Daniel G. S. Capelluto
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States
| |
Collapse
|
8
|
Zellner S, Schifferer M, Behrends C. Systematically defining selective autophagy receptor-specific cargo using autophagosome content profiling. Mol Cell 2021; 81:1337-1354.e8. [PMID: 33545068 DOI: 10.1016/j.molcel.2021.01.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 11/18/2020] [Accepted: 01/06/2021] [Indexed: 12/20/2022]
Abstract
Autophagy deficiency in fed conditions leads to the formation of protein inclusions highlighting the contribution of this lysosomal delivery route to cellular proteostasis. Selective autophagy pathways exist that clear accumulated and aggregated ubiquitinated proteins. Receptors for this type of autophagy (aggrephagy) include p62, NBR1, TOLLIP, and OPTN, which possess LC3-interacting regions and ubiquitin-binding domains (UBDs), thus working as a bridge between LC3/GABARAP proteins and ubiquitinated substrates. However, the identity of aggrephagy substrates and the redundancy of aggrephagy and related UBD-containing receptors remains elusive. Here, we combined proximity labeling and organelle enrichment with quantitative proteomics to systematically map the autophagic degradome targeted by UBD-containing receptors under basal and proteostasis-challenging conditions in human cell lines. We identified various autophagy substrates, some of which were differentially engulfed by autophagosomal and endosomal membranes via p62 and TOLLIP, respectively. Overall, this resource will allow dissection of the proteostasis contribution of autophagy to numerous individual proteins.
Collapse
Affiliation(s)
- Susanne Zellner
- Munich Cluster for Systems Neurology (SyNergy), Medical Faculty, Ludwig-Maximilians-University München, Feodor-Lynen Strasse 17, 81377 Munich, Germany
| | - Martina Schifferer
- Munich Cluster for Systems Neurology (SyNergy), German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
| | - Christian Behrends
- Munich Cluster for Systems Neurology (SyNergy), Medical Faculty, Ludwig-Maximilians-University München, Feodor-Lynen Strasse 17, 81377 Munich, Germany.
| |
Collapse
|
9
|
Lin CY, Nozawa T, Minowa-Nozawa A, Toh H, Hikichi M, Iibushi J, Nakagawa I. Autophagy Receptor Tollip Facilitates Bacterial Autophagy by Recruiting Galectin-7 in Response to Group A Streptococcus Infection. Front Cell Infect Microbiol 2021; 10:583137. [PMID: 33425778 PMCID: PMC7786282 DOI: 10.3389/fcimb.2020.583137] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 11/19/2020] [Indexed: 01/09/2023] Open
Abstract
Bacterial autophagy—a type of macroautophagy that is also termed xenophagy—selectively targets intracellular bacteria such as group A Streptococcus (GAS), a ubiquitous pathogen that causes numerous serious diseases, including pharyngitis, skin infections, and invasive life-threatening infections. Although bacterial autophagy is known to eliminate invading bacteria via the action of autophagy receptors, the underlying mechanism remains unclear. Herein, we elucidated that Tollip functions as a bacterial-autophagy receptor in addition to participating involved in the intracellular immunity mechanism that defends against bacterial infection. Tollip was recruited to GAS-containing endosomal vacuoles prior to the escape of GAS into the cytosol; additionally, Tollip knockout disrupted the recruitment of other autophagy receptors, such as NBR1, TAX1BP1, and NDP52, to GAS-containing autophagosomes and led to prolonged intracellular survival of GAS. Furthermore, Tollip was found to be required for the recruitment of galectin-1 and -7 to GAS-containing autophagosomes, and immunoprecipitation results indicated that Tollip interacts with galectin-7. Lastly, our data also revealed that galectin-1 and -7 are involved in the restriction of GAS replication in cells. These results demonstrated that Tollip modulates bacterial autophagy by recruiting other autophagy receptors and galectins.
Collapse
Affiliation(s)
- Ching-Yu Lin
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takashi Nozawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Atsuko Minowa-Nozawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hirotaka Toh
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Miyako Hikichi
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Junpei Iibushi
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Ichiro Nakagawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| |
Collapse
|
10
|
Sarmah P, Bharali R, Khatonier R, Khan A. Polymorphism in Toll interacting protein (TOLLIP) gene and its association with Visceral Leishmaniasis. GENE REPORTS 2020. [DOI: 10.1016/j.genrep.2020.100705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
11
|
Ryan TA, Phillips EO, Collier CL, Jb Robinson A, Routledge D, Wood RE, Assar EA, Tumbarello DA. Tollip coordinates Parkin-dependent trafficking of mitochondrial-derived vesicles. EMBO J 2020; 39:e102539. [PMID: 32311122 PMCID: PMC7265236 DOI: 10.15252/embj.2019102539] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 02/28/2020] [Accepted: 03/10/2020] [Indexed: 12/29/2022] Open
Abstract
Multiple mitochondrial quality control pathways exist to maintain the health of mitochondria and ensure cell homeostasis. Here, we investigate the role of the endosomal adaptor Tollip during the mitochondrial stress response and identify its interaction and colocalisation with the Parkinson's disease-associated E3 ubiquitin ligase Parkin. The interaction between Tollip and Parkin is dependent on the ubiquitin-binding CUE domain of Tollip, but independent of Tom1 and mitophagy. Interestingly, this interaction is independent of Parkin mitochondrial recruitment and ligase activity but requires an intact ubiquitin-like (UBL) domain. Importantly, Tollip regulates Parkin-dependent endosomal trafficking of a discrete subset of mitochondrial-derived vesicles (MDVs) to facilitate delivery to lysosomes. Retromer function and an interaction with Tom1 allow Tollip to facilitate late endosome/lysosome trafficking in response to mitochondrial stress. We find that upregulation of TOM20-positive MDVs upon mitochondrial stress requires Tollip interaction with ubiquitin, endosomal membranes and Tom1 to ensure their trafficking to the lysosomes. Thus, we conclude that Tollip, via an association with Parkin, is an essential coordinator to sort damaged mitochondrial-derived cargo to the lysosomes.
Collapse
Affiliation(s)
- Thomas A Ryan
- Biological Sciences, University of Southampton, Southampton, UK
| | | | | | | | | | - Rebecca E Wood
- Biological Sciences, University of Southampton, Southampton, UK
| | - Emelia A Assar
- Biological Sciences, University of Southampton, Southampton, UK
| | | |
Collapse
|
12
|
Martini AC, Gomez-Arboledas A, Forner S, Rodriguez-Ortiz CJ, McQuade A, Danhash E, Phan J, Javonillo D, Ha JV, Tram M, Trujillo-Estrada L, da Cunha C, Ager RR, Davila JC, Kitazawa M, Blurton-Jones M, Gutierrez A, Baglietto-Vargas D, Medeiros R, LaFerla FM. Amyloid-beta impairs TOM1-mediated IL-1R1 signaling. Proc Natl Acad Sci U S A 2019; 116:21198-21206. [PMID: 31570577 PMCID: PMC6800331 DOI: 10.1073/pnas.1914088116] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Defects in interleukin-1β (IL-1β)-mediated cellular responses contribute to Alzheimer's disease (AD). To decipher the mechanism associated with its pathogenesis, we investigated the molecular events associated with the termination of IL-1β inflammatory responses by focusing on the role played by the target of Myb1 (TOM1), a negative regulator of the interleukin-1β receptor-1 (IL-1R1). We first show that TOM1 steady-state levels are reduced in human AD hippocampi and in the brain of an AD mouse model versus respective controls. Experimentally reducing TOM1 affected microglia activity, substantially increased amyloid-beta levels, and impaired cognition, whereas enhancing its levels was therapeutic. These data show that reparation of the TOM1-signaling pathway represents a therapeutic target for brain inflammatory disorders such as AD. A better understanding of the age-related changes in the immune system will allow us to craft therapies to limit detrimental aspects of inflammation, with the broader purpose of sharply reducing the number of people afflicted by AD.
Collapse
Affiliation(s)
- Alessandra Cadete Martini
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Angela Gomez-Arboledas
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, Instituto de Investigación Biomédica de Málaga-IBIMA, Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), University of Málaga, Málaga 29010, Spain
| | - Stefania Forner
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Carlos J Rodriguez-Ortiz
- Center for Occupational and Environmental Health, School of Medicine, University of California, Irvine, CA 92697
| | - Amanda McQuade
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA 92697
| | - Emma Danhash
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA 92697
| | - Jimmy Phan
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Dominic Javonillo
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Jordan-Vu Ha
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Melanie Tram
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Laura Trujillo-Estrada
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, Instituto de Investigación Biomédica de Málaga-IBIMA, Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), University of Málaga, Málaga 29010, Spain
| | - Celia da Cunha
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Rahasson R Ager
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
| | - Jose C Davila
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, Instituto de Investigación Biomédica de Málaga-IBIMA, Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), University of Málaga, Málaga 29010, Spain
| | - Masashi Kitazawa
- Center for Occupational and Environmental Health, School of Medicine, University of California, Irvine, CA 92697
| | - Mathew Blurton-Jones
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA 92697
| | - Antonia Gutierrez
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, Instituto de Investigación Biomédica de Málaga-IBIMA, Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), University of Málaga, Málaga 29010, Spain
| | - David Baglietto-Vargas
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, Instituto de Investigación Biomédica de Málaga-IBIMA, Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), University of Málaga, Málaga 29010, Spain
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
| | - Rodrigo Medeiros
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697;
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Frank M LaFerla
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA 92697;
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697
| |
Collapse
|
13
|
Xiong W, Tang TX, Littleton E, Karcini A, Lazar IM, Capelluto DGS. Preferential phosphatidylinositol 5-phosphate binding contributes to a destabilization of the VHS domain structure of Tom1. Sci Rep 2019; 9:10868. [PMID: 31350523 PMCID: PMC6659632 DOI: 10.1038/s41598-019-47386-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 07/16/2019] [Indexed: 12/21/2022] Open
Abstract
Tom1 transports endosomal ubiquitinated proteins that are targeted for degradation in the lysosomal pathway. Infection of eukaryotic cells by Shigella flexneri boosts oxygen consumption and promotes the synthesis of phosphatidylinositol-5-phosphate (PtdIns5P), which triggers Tom1 translocation to signaling endosomes. Removing Tom1 from its cargo trafficking function hinders protein degradation in the host and, simultaneously, enables bacterial survival. Tom1 preferentially binds PtdIns5P via its VHS domain, but the effects of a reducing environment as well as PtdIns5P on the domain structure and function are unknown. Thermal denaturation studies demonstrate that, under reducing conditions, the monomeric Tom1 VHS domain switches from a three-state to a two-state transition behavior. PtdIns5P reduced thermostability, interhelical contacts, and conformational compaction of Tom1 VHS, suggesting that the phosphoinositide destabilizes the protein domain. Destabilization of Tom1 VHS structure was also observed with other phospholipids. Isothermal calorimetry data analysis indicates that, unlike ubiquitin, Tom1 VHS endothermically binds to PtdIns5P through two noncooperative binding sites, with its acyl chains playing a relevant role in the interaction. Altogether, these findings provide mechanistic insights about the recognition of PtdIns5P by the VHS domain that may explain how Tom1, when in a different VHS domain conformational state, interacts with downstream effectors under S. flexneri infection.
Collapse
Affiliation(s)
- Wen Xiong
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, United States
| | - Tuo-Xian Tang
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, United States
| | - Evan Littleton
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, United States
| | - Arba Karcini
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, United States
| | - Iulia M Lazar
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, United States
| | - Daniel G S Capelluto
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, United States.
| |
Collapse
|
14
|
Dominant TOM1 mutation associated with combined immunodeficiency and autoimmune disease. NPJ Genom Med 2019; 4:14. [PMID: 31263572 PMCID: PMC6597545 DOI: 10.1038/s41525-019-0088-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 06/04/2019] [Indexed: 01/19/2023] Open
Abstract
Mutations in several proteins functioning as endolysosomal components cause monogenic autoimmune diseases, of which pathogenesis is linked to increased endoplasmic reticulum stress, inefficient autophagy, and defective recycling of immune receptors. We report here a heterozygous TOM1 p.G307D missense mutation, detected by whole-exome sequencing, in two related patients presenting with early-onset autoimmunity, antibody deficiency, and features of combined immunodeficiency. The index patient suffered from recurrent respiratory tract infections and oligoarthritis since early teens, and later developed persistent low-copy EBV-viremia, as well as an antibody deficiency. Her infant son developed hypogammaglobulinemia, autoimmune enteropathy, interstitial lung disease, profound growth failure, and treatment-resistant psoriasis vulgaris. Consistent with previous knowledge on TOM1 protein function, we detected impaired autophagy and enhanced susceptibility to apoptosis in patient-derived cells. In addition, we noted diminished STAT and ERK1/2 signaling in patient fibroblasts, as well as poor IFN-γ and IL-17 secretion in T cells. The mutant TOM1 failed to interact with TOLLIP, a protein required for IL-1 recycling, PAMP signaling and autophagosome maturation, further strengthening the link between the candidate mutation and patient pathophysiology. In sum, we report here an identification of a novel gene, TOM1, associating with early-onset autoimmunity, antibody deficiency, and features of combined immunodeficiency. Other patient cases from unrelated families are needed to firmly establish a causal relationship between the genotype and the phenotype.
Collapse
|
15
|
Shah JA, Musvosvi M, Shey M, Horne DJ, Wells RD, Peterson GJ, Cox JS, Daya M, Hoal EG, Lin L, Gottardo R, Hanekom WA, Scriba TJ, Hatherill M, Hawn TR. A Functional Toll-Interacting Protein Variant Is Associated with Bacillus Calmette-Guérin-Specific Immune Responses and Tuberculosis. Am J Respir Crit Care Med 2017; 196:502-511. [PMID: 28463648 DOI: 10.1164/rccm.201611-2346oc] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
RATIONALE The molecular mechanisms that regulate tuberculosis susceptibility and bacillus Calmette-Guérin (BCG)-induced immunity are mostly unknown. However, induction of the adaptive immune response is a critical step in host control of Mycobacterium tuberculosis. Toll-interacting protein (TOLLIP) is a ubiquitin-binding protein that regulates innate immune responses, including Toll-like receptor signaling, which initiate adaptive immunity. TOLLIP variation is associated with susceptibility to tuberculosis, but the mechanism by which it regulates tuberculosis immunity is poorly understood. OBJECTIVES To identify functional TOLLIP variants and evaluate the role of TOLLIP variation on innate and adaptive immune responses to mycobacteria and susceptibility to tuberculosis. METHODS We used human cellular immunology approaches to characterize the role of a functional TOLLIP variant on monocyte mRNA expression and M. tuberculosis-induced monocyte immune functions. We also examined the association of TOLLIP variation with BCG-induced T-cell responses and susceptibility to latent tuberculosis infection. MEASUREMENTS AND MAIN RESULTS We identified a functional TOLLIP promoter region single-nucleotide polymorphism, rs5743854, which was associated with decreased TOLLIP mRNA expression in infant monocytes. After M. tuberculosis infection, TOLLIP-deficient monocytes demonstrated increased IL-6, increased nitrite, and decreased bacterial replication. The TOLLIP-deficiency G/G genotype was associated with decreased BCG-specific IL-2+ CD4+ T-cell frequency and proliferation. This genotype was also associated with increased susceptibility to latent tuberculosis infection. CONCLUSIONS TOLLIP deficiency is associated with decreased BCG-specific T-cell responses and increased susceptibility to tuberculosis. We hypothesize that the heightened antibacterial monocyte responses after vaccination of TOLLIP-deficient infants are responsible for decreased BCG-specific T-cell responses. Activating TOLLIP may provide a novel adjuvant strategy for BCG vaccination.
Collapse
Affiliation(s)
- Javeed A Shah
- 1 University of Washington School of Medicine, Seattle, Washington.,2 Veterans Affairs Puget Sound Health Care System, Seattle, Washington
| | | | - Muki Shey
- 3 South African Tuberculosis Vaccine Initiative and.,4 Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - David J Horne
- 1 University of Washington School of Medicine, Seattle, Washington
| | - Richard D Wells
- 1 University of Washington School of Medicine, Seattle, Washington
| | | | - Jeffery S Cox
- 5 University of California Berkeley, Berkeley, California
| | - Michelle Daya
- 6 Molecular Biology and Human Genetics, MRC Centre for Molecular and Cellular Biology, DST/NRF Centre of Excellence for Biomedical TB Research, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Eileen G Hoal
- 6 Molecular Biology and Human Genetics, MRC Centre for Molecular and Cellular Biology, DST/NRF Centre of Excellence for Biomedical TB Research, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Lin Lin
- 7 Department of Statistics, Pennsylvania State University, University Park, Pennsylvania; and
| | | | - Willem A Hanekom
- 3 South African Tuberculosis Vaccine Initiative and.,4 Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Thomas J Scriba
- 3 South African Tuberculosis Vaccine Initiative and.,4 Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Mark Hatherill
- 3 South African Tuberculosis Vaccine Initiative and.,4 Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Thomas R Hawn
- 1 University of Washington School of Medicine, Seattle, Washington
| |
Collapse
|
16
|
Kowalski EJA, Li L. Toll-Interacting Protein in Resolving and Non-Resolving Inflammation. Front Immunol 2017; 8:511. [PMID: 28529512 PMCID: PMC5418219 DOI: 10.3389/fimmu.2017.00511] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 04/18/2017] [Indexed: 12/17/2022] Open
Abstract
Innate leukocytes manifest dynamic and distinct inflammatory responses upon challenges with rising dosages of pathogen-associated molecular pattern molecules such as lipopolysaccharide (LPS). To differentiate signal strengths, innate leukocytes may utilize distinct intracellular signaling circuitries modulated by adaptor molecules. Toll-interacting protein (Tollip) is one of the critical adaptor molecules potentially playing key roles in modulating the dynamic adaptation of innate leukocytes to varying dosages of external stimulants. While Tollip may serve as a negative regulator of nuclear factor κ of activated B cells signaling pathway in cells challenged with higher dosages of LPS, it acts as a positive regulator for low-grade chronic inflammation in leukocytes programmed by subclinical low-dosages of LPS. This review aims to discuss recent progress in our understanding of complex innate leukocyte dynamics and its relevance in the pathogenesis of resolving versus non-resolving chronic inflammatory diseases.
Collapse
Affiliation(s)
- Elizabeth J A Kowalski
- Department of Biological Sciences, Virginia Polytechnic State University, Blacksburg, VA, USA
| | - Liwu Li
- Department of Biological Sciences, Virginia Polytechnic State University, Blacksburg, VA, USA
| |
Collapse
|
17
|
Ellena JF, Xiong W, Zhao X, Shanaiah N, Capelluto DGS. Backbone 1H, 15N, and 13C resonance assignments of the Tom1 VHS domain. BIOMOLECULAR NMR ASSIGNMENTS 2017; 11:1-4. [PMID: 27704363 DOI: 10.1007/s12104-016-9709-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 09/29/2016] [Indexed: 06/06/2023]
Abstract
Efficient trafficking of ubiquitinated receptors (cargo) to endosomes requires the recruitment of adaptor proteins that exhibit ubiquitin-binding domains for recognition and transport. Tom1 is an adaptor protein that not only associates with ubiquitinated cargo but also represents a phosphoinositide effector during specific bacterial infections. This phosphoinositide-binding property is associated with its N-terminal Vps27, Hrs, STAM (VHS) domain. Despite its biological relevance, there are no resonance assignments of Tom1 VHS available that can fully characterize its molecular interactions. Here, we report the nearly complete 1H, 15N, and 13C backbone resonance assignments of the VHS domain of human Tom1.
Collapse
Affiliation(s)
- Jeffrey F Ellena
- Biomolecular Magnetic Resonance Facility, University of Virginia, Charlottesville, VA, 22904, USA
| | - Wen Xiong
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Xiaolin Zhao
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA
| | | | - Daniel G S Capelluto
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA.
| |
Collapse
|
18
|
Tang T, Jo A, Deng J, Ellena JF, Lazar IM, Davis RM, Capelluto DGS. Structural, thermodynamic, and phosphatidylinositol 3-phosphate binding properties of Phafin2. Protein Sci 2017; 26:814-823. [PMID: 28152563 PMCID: PMC5368057 DOI: 10.1002/pro.3128] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 01/06/2017] [Accepted: 01/11/2017] [Indexed: 02/02/2023]
Abstract
Phafin2 is a phosphatidylinositol 3-phosphate (PtdIns(3)P) binding protein involved in the regulation of endosomal cargo trafficking and lysosomal induction of autophagy. Binding of Phafin2 to PtdIns(3)P is mediated by both its PH and FYVE domains. However, there are no studies on the structural basis, conformational stability, and lipid interactions of Phafin2 to better understand how this protein participates in signaling at the surface of endomembrane compartments. Here, we show that human Phafin2 is a moderately elongated monomer of ∼28 kDa with an intensity-average hydrodynamic diameter of ∼7 nm. Circular dichroism (CD) analysis indicates that Phafin2 exhibits an α/β structure and predicts ∼40% random coil content in the protein. Heteronuclear NMR data indicates that a unique conformation of Phafin2 is present in solution and dispersion of resonances suggests that the protein exhibits random coiled regions, in agreement with the CD data. Phafin2 is stable, displaying a melting temperature of 48.4°C. The folding-unfolding curves, obtained using urea- and guanidine hydrochloride-mediated denaturation, indicate that Phafin2 undergoes a two-state native-to-denatured transition. Analysis of these transitions shows that the free energy change for urea- and guanidine hydrochloride-induced Phafin2 denaturation in water is ∼4 kcal mol-1 . PtdIns(3)P binding to Phafin2 occurs with high affinity, triggering minor conformational changes in the protein. Taken together, these studies represent a platform for establishing the structural basis of Phafin2 molecular interactions and the role of the two potentially redundant PtdIns(3)P-binding domains of the protein in endomembrane compartments.
Collapse
Affiliation(s)
- Tuo‐Xian Tang
- Protein Signaling Domains Laboratory, Department of Biological SciencesBiocomplexity Institute, and Center for Soft Matter and Biological Physics, Virginia TechBlacksburgVirginia24061
| | - Ami Jo
- Department of Chemical EngineeringVirginia TechBlacksburgVirginia24061
| | - Jingren Deng
- Department of Biological SciencesVirginia TechBlacksburgVirginia24061
| | - Jeffrey F. Ellena
- Biomolecular Magnetic Resonance Facility, University of VirginiaCharlottesvilleVirginia22904
| | - Iulia M. Lazar
- Department of Biological SciencesVirginia TechBlacksburgVirginia24061
| | - Richey M. Davis
- Department of Chemical EngineeringVirginia TechBlacksburgVirginia24061
| | - Daniel G. S. Capelluto
- Protein Signaling Domains Laboratory, Department of Biological SciencesBiocomplexity Institute, and Center for Soft Matter and Biological Physics, Virginia TechBlacksburgVirginia24061
| |
Collapse
|
19
|
Tang TX, Xiong W, Finkielstein CV, Capelluto DGS. Identification of Lipid Binding Modulators Using the Protein-Lipid Overlay Assay. Methods Mol Biol 2017; 1647:197-206. [PMID: 28809004 DOI: 10.1007/978-1-4939-7201-2_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The protein-lipid overlay assay is an inexpensive, easy-to-implement, and high-throughput methodology that employs nitrocellulose membranes to immobilize lipids in order to rapid screen and identify protein-lipid interactions. In this chapter, we show how this methodology can identify potential modulators of protein-lipid interactions by screening water-soluble lipid competitors or even the introduction of pH changes during the binding assay to identify pH-dependent lipid binding events.
Collapse
Affiliation(s)
- Tuo-Xian Tang
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute, Virginia Tech, Blacksburg, VA, 24061, USA
- Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Wen Xiong
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute, Virginia Tech, Blacksburg, VA, 24061, USA
- Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Carla V Finkielstein
- Integrated Cellular Responses Laboratory, Department of Biological Sciences, Biocomplexity Institute, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Daniel G S Capelluto
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute, Virginia Tech, Blacksburg, VA, 24061, USA.
- Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA.
| |
Collapse
|
20
|
Abstract
In this issue of Structure, Xiao et al. (2015) describe a new mechanism of regulation of lipid binding. Structural and functional studies demonstrate that Tom1 interactions with the cargo sorting protein Tollip induce the partially unfolded Tom1-binding domain of Tollip to fold. This folding modulates lipid binding of Tollip, mediating its dissociation from PI(3)P and committing Tollip to cargo trafficking.
Collapse
|
21
|
Abstract
Innate immune responses are key to maintain adequate host-microbial interactions. However, those signals are needed to efficiently trigger rapid and targeted antimicrobial responses in case of pathogen encounter. Several molecules have evolved to regulate intensity and coordinate signaling to avoid detrimental consequences to the host. Regulation can occur at the cell surface, within the cytoplasm, and at the transcriptional level. Innate immune regulation seems to be equally important than stimulation, as disruption of immunoregulatory molecules modulates the risk for several diseases. This is the case for colitis and inflammatory bowel disease but also colorectal cancer and intestinal infections. In this review, we recapitulate the molecular mechanisms underlying regulation of innate immune signals and mention their implications in several disease states including inflammatory bowel disease.
Collapse
|
22
|
Xiao S, Ellena JF, Armstrong GS, Capelluto DGS. Structure of the GAT domain of the endosomal adapter protein Tom1. Data Brief 2016; 7:344-8. [PMID: 26977434 PMCID: PMC4781976 DOI: 10.1016/j.dib.2016.02.042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 02/09/2016] [Accepted: 02/17/2016] [Indexed: 11/23/2022] Open
Abstract
Cellular homeostasis requires correct delivery of cell-surface receptor proteins (cargo) to their target subcellular compartments. The adapter proteins Tom1 and Tollip are involved in sorting of ubiquitinated cargo in endosomal compartments. Recruitment of Tom1 to the endosomal compartments is mediated by its GAT domain’s association to Tollip’s Tom1-binding domain (TBD). In this data article, we report the solution NMR-derived structure of the Tom1 GAT domain. The estimated protein structure exhibits a bundle of three helical elements. We compare the Tom1 GAT structure with those structures corresponding to the Tollip TBD- and ubiquitin-bound states.
Collapse
Affiliation(s)
- Shuyan Xiao
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute, Virginia Tech, Blacksburg, VA 24061, USA; School of Materials and Metallurgy, Inner Mongolia University of Science and Technology, PR China
| | - Jeffrey F Ellena
- Department of Chemistry and Biochemistry, University of Virginia, Charlottesville, VA 22904, USA
| | - Geoffrey S Armstrong
- Departments of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309, USA
| | - Daniel G S Capelluto
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Biocomplexity Institute, Virginia Tech, Blacksburg, VA 24061, USA
| |
Collapse
|