1
|
van der Beek J, de Heus C, Sanza P, Liv N, Klumperman J. Loss of the HOPS complex disrupts early-to-late endosome transition, impairs endosomal recycling and induces accumulation of amphisomes. Mol Biol Cell 2024; 35:ar40. [PMID: 38198575 PMCID: PMC10916860 DOI: 10.1091/mbc.e23-08-0328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 12/22/2023] [Accepted: 01/05/2024] [Indexed: 01/12/2024] Open
Abstract
The multisubunit HOPS tethering complex is a well-established regulator of lysosome fusion with late endosomes and autophagosomes. However, the role of the HOPS complex in other stages of endo-lysosomal trafficking is not well understood. To address this, we made HeLa cells knocked out for the HOPS-specific subunits Vps39 or Vps41, or the HOPS-CORVET-core subunits Vps18 or Vps11. In all four knockout cells, we found that endocytosed cargos were trapped in enlarged endosomes that clustered in the perinuclear area. By correlative light-electron microscopy, these endosomes showed a complex ultrastructure and hybrid molecular composition, displaying markers for early (Rab5, PtdIns3P, EEA1) as well as late (Rab7, CD63, LAMP1) endosomes. These "HOPS bodies" were not acidified, contained enzymatically inactive cathepsins and accumulated endocytosed cargo and cation-independent mannose-6-phosphate receptor (CI-MPR). Consequently, CI-MPR was depleted from the TGN, and secretion of lysosomal enzymes to the extracellular space was enhanced. Strikingly, HOPS bodies also contained the autophagy proteins p62 and LC3, defining them as amphisomes. Together, these findings show that depletion of the lysosomal HOPS complex has a profound impact on the functional organization of the entire endosomal system and suggest the existence of a HOPS-independent mechanism for amphisome formation.
Collapse
Affiliation(s)
- Jan van der Beek
- Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Cecilia de Heus
- Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Paolo Sanza
- Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Nalan Liv
- Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Judith Klumperman
- Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, 3584 CX Utrecht, The Netherlands
| |
Collapse
|
2
|
Yao Y, Xu Y, Yu L, Xue T, Xiao Z, Tin P, Fung H, Ma H, Yun J, Yam JWP. NHE7 upregulation potentiates the uptake of small extracellular vesicles by enhancing maturation of macropinosomes in hepatocellular carcinoma. Cancer Commun (Lond) 2024; 44:251-272. [PMID: 38152992 PMCID: PMC10876205 DOI: 10.1002/cac2.12515] [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: 03/06/2023] [Revised: 12/13/2023] [Accepted: 12/18/2023] [Indexed: 12/29/2023] Open
Abstract
BACKGROUND Small extracellular vesicles (sEVs) mediate intercellular communication that contributes to hepatocellular carcinoma (HCC) progression via multifaceted pathways. The success of cell entry determines the effect of sEV on recipient cells. Here, we aimed to delineate the mechanisms underlying the uptake of sEV in HCC. METHODS Macropinocytosis was examined by the ability of cells to internalize dextran and sEV. Macropinocytosis was analyzed in Na(+)/H(+) exchanger 7 (NHE7)-knockdown and -overexpressing cells. The properties of cells were studied using functional assays. pH biosensor was used to evaluate the intracellular and endosomal pH. The expression of NHE7 in patients' liver tissues was examined by immunofluorescent staining. Inducible silencing of NHE7 in established tumors was performed to reveal the therapeutic potential of targeting NHE7. RESULTS The data revealed that macropinocytosis controlled the internalization of sEVs and their oncogenic effect on recipient cells. It was found that metastatic HCC cells exhibited the highest efficiency of sEV uptake relative to normal liver cells and non-metastatic HCC cells. Attenuation of macropinocytic activity by 5-(N-ethyl-N-isopropyl)-amiloride (EIPA) limited the entry of sEVs and compromised cell aggressiveness. Mechanistically, we delineated that high level of NHE7, a sodium-hydrogen exchanger, alkalized intracellular pH and acidized endosomal pH, leading to the maturation of macropinosomes. Inducible inhibition of NHE7 in established tumors developed in mice delayed tumor development and suppressed lung metastasis. Clinically, NHE7 expression was upregulated and linked to dismal prognosis of HCC. CONCLUSIONS This study advances the understanding that NHE7 enhances sEV uptake by macropinocytosis to promote the malignant properties of HCC cells. Inhibition of sEV uptake via macropinocytosis can be exploited as a treatment alone or in combination with conventional therapeutic approaches for HCC.
Collapse
Affiliation(s)
- Yue Yao
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
- Department of Endocrinology and MetabolismSecond Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjingP. R. China
| | - Yi Xu
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
- Department of Hepatopancreatobiliary SurgerySecond Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjingP. R. China
- State Key Laboratory of Oncology in South ChinaCancer Center of Sun Yat‐sen UniversityGuangzhouGuangdongP. R. China
| | - Liang Yu
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
- Department of Hepatopancreatobiliary SurgerySecond Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjingP. R. China
| | - Ting‐Mao Xue
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
- Department of Hepatobiliary Surgery IIZhujiang HospitalSouthern Medical UniversityGuangzhouGuangdongP. R. China
| | - Zhi‐Jie Xiao
- Scientific Research CenterThe Seventh Affiliated HospitalSun Yat‐sen UniversityShenzhenGuangdongP. R. China
| | - Pui‐Chi Tin
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
| | - Hiu‐Ling Fung
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
| | - Hoi‐Tang Ma
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
- State Key Laboratory of Liver ResearchThe University of Hong KongHong KongP. R. China
| | - Jing‐Ping Yun
- Department of PathologyCancer Center of Sun Yat‐sen UniversityGuangzhouGuangdongP. R. China
| | - Judy Wai Ping Yam
- Department of PathologySchool of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongP. R. China
- State Key Laboratory of Liver ResearchThe University of Hong KongHong KongP. R. China
| |
Collapse
|
3
|
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
|
4
|
Domingues N, Marques ARA, Calado RDA, Ferreira IS, Ramos C, Ramalho J, Soares MIL, Pereira T, Oliveira L, Vicente JR, Wong LH, Simões ICM, Pinho E Melo TMVD, Peden A, Almeida CG, Futter CE, Puertollano R, Vaz WLC, Vieira OV. Oxidized cholesteryl ester induces exocytosis of dysfunctional lysosomes in lipidotic macrophages. Traffic 2023; 24:284-307. [PMID: 37129279 DOI: 10.1111/tra.12888] [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: 12/13/2022] [Revised: 03/29/2023] [Accepted: 04/20/2023] [Indexed: 05/03/2023]
Abstract
A key event in atherogenesis is the formation of lipid-loaded macrophages, lipidotic cells, which exhibit irreversible accumulation of undigested modified low-density lipoproteins (LDL) in lysosomes. This event culminates in the loss of cell homeostasis, inflammation, and cell death. Nevertheless, the exact chemical etiology of atherogenesis and the molecular and cellular mechanisms responsible for the impairment of lysosome function in plaque macrophages are still unknown. Here, we demonstrate that macrophages exposed to cholesteryl hemiazelate (ChA), one of the most prevalent products of LDL-derived cholesteryl ester oxidation, exhibit enlarged peripheral dysfunctional lysosomes full of undigested ChA and neutral lipids. Both lysosome area and accumulation of neutral lipids are partially irreversible. Interestingly, the dysfunctional peripheral lysosomes are more prone to fuse with the plasma membrane, secreting their undigested luminal content into the extracellular milieu with potential consequences for the pathology. We further demonstrate that this phenotype is mechanistically linked to the nuclear translocation of the MiT/TFE family of transcription factors. The induction of lysosome biogenesis by ChA appears to partially protect macrophages from lipid-induced cytotoxicity. In sum, our data show that ChA is involved in the etiology of lysosome dysfunction and promotes the exocytosis of these organelles. This latter event is a new mechanism that may be important in the pathogenesis of atherosclerosis.
Collapse
Affiliation(s)
- Neuza Domingues
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - André R A Marques
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Rita Diogo Almeida Calado
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Inês S Ferreira
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Cristiano Ramos
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - José Ramalho
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Maria I L Soares
- CQC and Department of Chemistry, University of Coimbra, Coimbra, Portugal
| | - Telmo Pereira
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Luís Oliveira
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - José R Vicente
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Louise H Wong
- Department of Cell Biology, UCL Institute of Ophthalmology, London, UK
| | - Inês C M Simões
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | | | - Andrew Peden
- Department of Biomedical Science & Center for Membrane Interactions and Dynamics, University of Sheffield, UK
| | - Cláudia Guimas Almeida
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Clare E Futter
- Department of Cell Biology, UCL Institute of Ophthalmology, London, UK
| | - Rosa Puertollano
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, USA
| | - Winchil L C Vaz
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Otília V Vieira
- iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, NMS|FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| |
Collapse
|
5
|
Lee J, Hyun DH. The Interplay between Intracellular Iron Homeostasis and Neuroinflammation in Neurodegenerative Diseases. Antioxidants (Basel) 2023; 12:antiox12040918. [PMID: 37107292 PMCID: PMC10135822 DOI: 10.3390/antiox12040918] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/23/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
Iron is essential for life. Many enzymes require iron for appropriate function. However, dysregulation of intracellular iron homeostasis produces excessive reactive oxygen species (ROS) via the Fenton reaction and causes devastating effects on cells, leading to ferroptosis, an iron-dependent cell death. In order to protect against harmful effects, the intracellular system regulates cellular iron levels through iron regulatory mechanisms, including hepcidin-ferroportin, divalent metal transporter 1 (DMT1)-transferrin, and ferritin-nuclear receptor coactivator 4 (NCOA4). During iron deficiency, DMT1-transferrin and ferritin-NCOA4 systems increase intracellular iron levels via endosomes and ferritinophagy, respectively. In contrast, repleting extracellular iron promotes cellular iron absorption through the hepcidin-ferroportin axis. These processes are regulated by the iron-regulatory protein (IRP)/iron-responsive element (IRE) system and nuclear factor erythroid 2-related factor 2 (Nrf2). Meanwhile, excessive ROS also promotes neuroinflammation by activating the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). NF-κB forms inflammasomes, inhibits silent information regulator 2-related enzyme 1 (SIRT1), and induces pro-inflammatory cytokines (IL-6, TNF-α, and IL-1β). Furthermore, 4-hydroxy-2,3-trans-nonenal (4-HNE), the end-product of ferroptosis, promotes the inflammatory response by producing amyloid-beta (Aβ) fibrils and neurofibrillary tangles in Alzheimer's disease, and alpha-synuclein aggregation in Parkinson's disease. This interplay shows that intracellular iron homeostasis is vital to maintain inflammatory homeostasis. Here, we review the role of iron homeostasis in inflammation based on recent findings.
Collapse
Affiliation(s)
- Jaewang Lee
- Department of Life Science, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Dong-Hoon Hyun
- Department of Life Science, Ewha Womans University, Seoul 03760, Republic of Korea
| |
Collapse
|
6
|
Placidi G, Mattu C, Ciardelli G, Campa CC. Small molecules targeting endocytic uptake and recycling pathways. Front Cell Dev Biol 2023; 11:1125801. [PMID: 36968200 PMCID: PMC10036367 DOI: 10.3389/fcell.2023.1125801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 02/23/2023] [Indexed: 03/12/2023] Open
Abstract
Over the past years a growing number of studies highlighted the pivotal role of intracellular trafficking in cell physiology. Among the distinct transport itineraries connecting the endocytic system, both internalization (endocytosis) and recycling (endocytic recycling) pathways were found fundamental to ensure cellular sensing, cell-to-cell communication, cellular division, and collective cell migration in tissue specific-contexts. Consistently, the dysregulation of endocytic trafficking pathways is correlated with several human diseases including both cancers and neurodegeneration. Aimed at suppress specific intracellular trafficking routes involved in disease onset and progression, huge efforts have been made to identify small molecule inhibitors with suitable pharmacological properties for in vivo administration. Here, we review most used drugs and recently discovered small molecules able to block endocytosis and endocytic recycling pathways. We characterize such pharmacological inhibitors by emphasizing their target specificity, molecular affinity, biological activity and efficacy in both in vitro and in vivo experimental models.
Collapse
Affiliation(s)
- Giampaolo Placidi
- Italian Institute for Genomic Medicine, Candiolo, Italy
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Clara Mattu
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Gianluca Ciardelli
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
- Chemical-Physical Processes, National Research Council (CNR-IPCF), Pisa, Italy
| | - Carlo C. Campa
- Italian Institute for Genomic Medicine, Candiolo, Italy
- Candiolo Cancer Institute, FPO-IRCCS, Candiolo, Italy
| |
Collapse
|
7
|
Pham TT, Chen H, Nguyen PHD, Jayasinghe MK, Le AH, Le MT. Endosomal escape of nucleic acids from extracellular vesicles mediates functional therapeutic delivery. Pharmacol Res 2023; 188:106665. [PMID: 36657503 DOI: 10.1016/j.phrs.2023.106665] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/06/2023] [Accepted: 01/15/2023] [Indexed: 01/19/2023]
Abstract
Extracellular vesicles hold great promise as a drug delivery platform for RNA-based therapeutics. However, there is a lack of experimental evidence for the intracellular trafficking of nucleic acid cargos, specifically, whether they are capable of escaping from the endolysosomal confinement in the recipient cells to be released into the cytosol and hence, interact with their cytoplasmic targets. Here, we demonstrated how red blood cell-derived extracellular vesicles (RBCEVs) release their therapeutic RNA/DNA cargos at specific intracellular compartments characteristic of late endosomes and lysosomes. The released cargos were functional and capable of knocking down genes of interest in recipient cells, resulting in tumor suppression in vitro and in an acute myeloid leukemia murine model without causing significant toxicity. Notably, surface functionalization of RBCEVs with an anti-human CXCR4 antibody facilitated their specific uptake by CXCR4+ leukemic cells, leading to enhanced gene silencing efficiency. Our results provide insights into the cellular uptake mechanisms and endosomal escape routes of nucleic acid cargos delivered by RBCEVs which have important implications for further improvements of the RBCEV-based delivery system.
Collapse
Affiliation(s)
- Tuan Thach Pham
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Huan Chen
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Biomedical Sciences, City University of Hong Kong, Hong Kong Special Administrative Region of China
| | - Phuong Hoang Diem Nguyen
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Migara Kavishka Jayasinghe
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Anh Hong Le
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Minh Tn Le
- Department of Pharmacology and Institute for Digital Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
| |
Collapse
|
8
|
Ouyang Q, Schmidt M, Morrow EM. Dynamic Measurement of Endosome-Lysosome Fusion in Neurons Using High-Content Imaging. Methods Mol Biol 2023; 2683:201-212. [PMID: 37300777 DOI: 10.1007/978-1-0716-3287-1_16] [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] [Indexed: 06/12/2023]
Abstract
Endocytosis is a dynamic cellular process that actively transports particles into a cell. Late endosome fusion with the lysosome is a crucial step in the delivery of newly synthesized lysosomal proteins and endocytosed cargo for degradation. Disturbing this step in neurons is associated with neurological disorders. Thus, studying endosome-lysosome fusion in neurons will provide new insight into the mechanisms of these diseases and open new possibilities for therapeutic treatment. However, measuring endosome-lysosome fusion is challenging and time consuming, which limits the research in this area. Here we developed a high throughput method using pH-insensitive dye-conjugated dextrans and the Opera Phenix® High Content Screening System. By using this method, we successfully separated endosomes and lysosomes in neurons, and time-lapse images were collected to capture endosome-lysosome fusion events in hundreds of cells. Both assay set-up and analysis can be completed in an expeditious and efficient manner.
Collapse
Affiliation(s)
- Qing Ouyang
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA.
- Center for Translational Neuroscience, Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, RI, USA.
- Brown University, Laboratories for Molecular Medicine, Providence, RI, USA.
| | - Michael Schmidt
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
- Center for Translational Neuroscience, Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, RI, USA
| | - Eric M Morrow
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA.
- Center for Translational Neuroscience, Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, RI, USA.
- Brown University, Laboratories for Molecular Medicine, Providence, RI, USA.
| |
Collapse
|
9
|
Sun-Wada GH, Wada Y. Exploring the Link between Vacuolar-Type Proton ATPase and Epithelial Cell Polarity. Biol Pharm Bull 2022; 45:1419-1425. [PMID: 36184498 DOI: 10.1248/bpb.b22-00205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vacuolar-type H+-ATPase (V-ATPase) was first identified as an electrogenic proton pump that acidifies the lumen of intracellular organelles. Subsequently, it was observed that the proton pump also participates in the acidification of extracellular compartments. V-ATPase plays important roles in a wide range of cell biological processes and physiological functions by generating an acidic pH; therefore, it has attracted much attention not only in basic research but also in pathological and clinical aspects. Emerging evidence indicates that the luminal acidic endocytic organelles and their trafficking may function as important hubs that connect and coordinate various signaling pathways. Various pharmacological analyses have suggested that acidic endocytic organelles are important for the maintenance of cell polarity. Recently, several studies using genetic approaches have revealed the involvement of V-ATPase in the establishment and maintenance of apico-basal polarity. This review provides a brief overview of the relationship between the polarity of epithelial cells and V-ATPase as well as V-ATPase driven luminal acidification.
Collapse
Affiliation(s)
- Ge-Hong Sun-Wada
- Faculty of Pharmaceutical Sciences, Doshisha Women's College of Liberal Arts
| | - Yoh Wada
- Division of Biological Science, Institute of Scientific and Industrial Research, Osaka University
| |
Collapse
|
10
|
Avalos PN, Forsthoefel DJ. An Emerging Frontier in Intercellular Communication: Extracellular Vesicles in Regeneration. Front Cell Dev Biol 2022; 10:849905. [PMID: 35646926 PMCID: PMC9130466 DOI: 10.3389/fcell.2022.849905] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/28/2022] [Indexed: 12/12/2022] Open
Abstract
Regeneration requires cellular proliferation, differentiation, and other processes that are regulated by secreted cues originating from cells in the local environment. Recent studies suggest that signaling by extracellular vesicles (EVs), another mode of paracrine communication, may also play a significant role in coordinating cellular behaviors during regeneration. EVs are nanoparticles composed of a lipid bilayer enclosing proteins, nucleic acids, lipids, and other metabolites, and are secreted by most cell types. Upon EV uptake by target cells, EV cargo can influence diverse cellular behaviors during regeneration, including cell survival, immune responses, extracellular matrix remodeling, proliferation, migration, and differentiation. In this review, we briefly introduce the history of EV research and EV biogenesis. Then, we review current understanding of how EVs regulate cellular behaviors during regeneration derived from numerous studies of stem cell-derived EVs in mammalian injury models. Finally, we discuss the potential of other established and emerging research organisms to expand our mechanistic knowledge of basic EV biology, how injury modulates EV biogenesis, cellular sources of EVs in vivo, and the roles of EVs in organisms with greater regenerative capacity.
Collapse
Affiliation(s)
- Priscilla N. Avalos
- Department of Cell Biology, College of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States
| | - David J. Forsthoefel
- Department of Cell Biology, College of Medicine, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States
| |
Collapse
|
11
|
Overexpression of V-ATPase B2 attenuates lung injury/fibrosis by stabilizing lysosomal membrane permeabilization and increasing collagen degradation. Exp Mol Med 2022; 54:662-672. [PMID: 35624153 PMCID: PMC9166714 DOI: 10.1038/s12276-022-00776-2] [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: 01/21/2022] [Revised: 03/02/2022] [Accepted: 03/10/2022] [Indexed: 11/29/2022] Open
Abstract
Excessive oxidative stress causes lysosomal membrane permeabilization (LMP), which leads to cell death. Vacuolar ATPase (V-ATPase) is the enzyme responsible for pumping H+ into the cytosol and thus maintaining intracellular pH. Previously, we reported that V-ATPase B2 subunit expression is upregulated in the TiO2-exposed lung epithelium. We investigated the role of the lysosomal V-ATPase B2 subunit in oxidative stress-induced alveolar epithelial cell death and in an experimental lung injury/fibrosis model. Overexpression of V-ATPase B2 increased lysosomal pH and lysosomal activities in the cells. In the presence of H2O2, overexpression of V-ATPase B2 increased survival, and silencing of V-ATPase B2 dramatically increased cell death. Overexpression of V-ATPase B2 diminished H2O2-triggered LMP, as evidenced by a reduction in acridine orange staining and leakage of cathepsin D from the lysosome to the cytoplasm. In addition, V-ATPase B2-overexpressing macrophages exhibited significantly enhanced uptake and degradation of collagen. V-ATPase B2-overexpressing transgenic mice showed significant inhibition of the bleomycin-induced increases in lung inflammation and fibrosis. We conclude that V-ATPase B2 is critical for maintaining lysosomal activities against excessive oxidative stress by stabilizing LMP. Our findings reveal a previously unknown role of this V-ATPase subunit in a lung injury and fibrosis model. An enzyme involved in maintaining the correct pH inside the lysosome, an organelle involved in disposal of cellular waste, also plays a critical role in preventing lung injury. Using human lung cells and mouse models of lung fibrosis, a team led by Sung Woo Park from Soonchunhyang University Bucheon Hospital, South Korea, showed that a overexpression of subunit of the vacuolar ATPase enzyme B2, which pumps protons into cellular compartments to create more acidic environments, helps to boost lysosomal activities that lead to prevent oxidative stress-induced cell death and alleviate experimental lung injury/fibrosis. In addition, V-ATPase B2 overexpressed macrophages increased collagen uptake and degradation activities. The findings point to the vacuolar ATPase, and its B2 subunit in particular, as a promising drug target for future treatments of pulmonary fibrosis.
Collapse
|
12
|
Han X, Wang C, Song L, Wang X, Tang S, Hou T, Liu C, Liang X, Qiu C, Wang Y, Du Y. KIBRA regulates amyloid β metabolism by controlling extracellular vesicles secretion. EBioMedicine 2022; 78:103980. [PMID: 35367771 PMCID: PMC8983338 DOI: 10.1016/j.ebiom.2022.103980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 03/21/2022] [Accepted: 03/21/2022] [Indexed: 11/30/2022] Open
Abstract
Background Previous research has revealed that KIBRA controls secretion of extracellular vesicles (EVs) by inhibiting the proteasomal degradation of Rab27a and EVs play an important role in amyloid β (Aβ) metabolism and transmission during Alzheimer's disease (AD) pathogenesis. Here, we further test the hypothesis that KIBRA regulates Aβ metabolism via the endosomal-lysosomal system. Methods We generated KIBRA knockout mice on a 5XFAD background and KIBRA knockdown cells in murine HT22 cells with stably overexpressing APP. Various forms of Aβ and quantification of EVs were analyzed by biochemical methods and nanoparticle tracking analysis, respectively. Multivesicular bodies (MVBs) were visualized by electron microscopy and confocal fluorescent microscopy. In a population-based cohort (n = 1419), KIBRA genotypes and plasma Aβ levels were analyzed using multiple-PCR amplification and Simoa, respectively. Findings Multiple forms of Aβ were dramatically attenuated in KIBRA knockout mouse brain, including monomers, oligomers, and extracellular deposition, but KIBRA knockout had no effect on intraneuronal APP C-terminal fragment β (APP-CTFβ)/Aβ levels. KIBRA depletion also decreased APP-CTFβ/Aβ-associated EVs secretion and subsequently enhanced MVBs number. Furthermore, we found that excessive accumulation of MVBs harboring APP-CTFβ/Aβ promoted the MVBs-lysosome fusion for degradation and inhibition of lysosomal function rescued secretion of APP-CTFβ/Aβ-associated EVs. More importantly, whole exon sequencing of KIBRA in a large population-based cohort identified the association of KIBRA rs28421695 polymorphism with plasma Aβ levels. Interpretation These results demonstrate that KIBRA regulates Aβ metabolism via controlling the secretion of APP-CTFβ/Aβ-associated EVs. Funding National Key R&D Program of China, and National Natural Science Foundation of China.
Collapse
Affiliation(s)
- Xiaolei Han
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China
| | - Chaoqun Wang
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China
| | - Lin Song
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China; Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, PR China; Shandong Provincial Clinical Research Center for Neurological Diseases, Jinan, Shandong, PR China
| | - Xiaojie Wang
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China
| | - Shi Tang
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China; Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, PR China; Shandong Provincial Clinical Research Center for Neurological Diseases, Jinan, Shandong, PR China
| | - Tingting Hou
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China; Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, PR China; Shandong Provincial Clinical Research Center for Neurological Diseases, Jinan, Shandong, PR China
| | - Cuicui Liu
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China; Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, PR China; Shandong Provincial Clinical Research Center for Neurological Diseases, Jinan, Shandong, PR China
| | - Xiaoyan Liang
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China
| | - Chengxuan Qiu
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China; Department of Neurobiology, Care Sciences and Society, Aging Research Center and Center for Alzheimer Research, Karolinska Institutet-Stockholm University, Stockholm, Sweden
| | - Yongxiang Wang
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, PR China; Shandong Provincial Clinical Research Center for Neurological Diseases, Jinan, Shandong, PR China.
| | - Yifeng Du
- Department of Neurology, Shandong Provincial Hospital, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, PR China; Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, PR China; Shandong Provincial Clinical Research Center for Neurological Diseases, Jinan, Shandong, PR China.
| |
Collapse
|
13
|
Loss of Christianson Syndrome Na +/H + Exchanger 6 (NHE6) Causes Abnormal Endosome Maturation and Trafficking Underlying Lysosome Dysfunction in Neurons. J Neurosci 2021; 41:9235-9256. [PMID: 34526390 PMCID: PMC8570832 DOI: 10.1523/jneurosci.1244-20.2021] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/05/2021] [Accepted: 08/07/2021] [Indexed: 01/08/2023] Open
Abstract
Loss-of-function mutations in endosomal Na+/H+ exchanger 6 (NHE6) cause the X-linked neurologic disorder Christianson syndrome. Patients exhibit symptoms associated with both neurodevelopmental and neurodegenerative abnormalities. While loss of NHE6 has been shown to overacidify the endosome lumen, and is associated with endolysosome neuropathology, NHE6-mediated mechanisms in endosome trafficking and lysosome function have been understudied. Here, we show that NHE6-null mouse neurons demonstrate worsening lysosome function with time in culture, likely as a result of defective endosome trafficking. NHE6-null neurons exhibit overall reduced lysosomal proteolysis despite overacidification of the endosome and lysosome lumen. Akin to Nhx1 mutants in Saccharomyces cerevisiae, we observe decreased endosome-lysosome fusion in NHE6-null neurons. Also, we find premature activation of pH-dependent cathepsin D (CatD) in endosomes. While active CatD is increased in endosomes, CatD activation and CatD protein levels are reduced in the lysosome. Protein levels of another mannose 6-phosphate receptor (M6PR)-dependent enzyme, β-N-acetylglucosaminidase, were also decreased in lysosomes of NHE6-null neurons. M6PRs accumulate in late endosomes, suggesting defective M6PR recycling and retromer function in NHE6-null neurons. Finally, coincident with decreased endosome-lysosome fusion, using total internal reflection fluorescence, we also find a prominent increase in fusion between endosomal multivesicular bodies and the plasma membrane, indicating enhanced exosome secretion from NHE6-null neurons. In summary, in addition to overacidification of endosomes and lysosomes, loss of NHE6 leads to defects in endosome maturation and trafficking, including enhanced exosome release, contributing to lysosome deficiency and potentially leading to neurodegenerative disease. SIGNIFICANCE STATEMENT Loss-of-function mutations in the endosomal Na+/H+ exchanger 6 (NHE6) cause Christianson syndrome, an X-linked neurologic disorder. Loss of NHE6 has been shown to overacidify endosomes; however, endosome trafficking mechanisms have been understudied, and the mechanisms leading to neurodegeneration are largely unknown. In NHE6-null mouse neurons in vitro, we find worsening lysosome function with days in culture. Notably, pH-dependent lysosome enzymes, such as cathepsin D, have reduced activity in lysosomes yet increased, precocious activity in endosomes in NHE6-null neurons. Further, endosomes show reduced fusion to lysosomes, and increased fusion to the plasma membrane with increased exosome release. This study identifies new mechanisms involving defective endosome maturation and trafficking that impair lysosome function in Christianson syndrome, likely contributing to neurodegeneration.
Collapse
|
14
|
Raudenska M, Balvan J, Masarik M. Crosstalk between autophagy inhibitors and endosome-related secretory pathways: a challenge for autophagy-based treatment of solid cancers. Mol Cancer 2021; 20:140. [PMID: 34706732 PMCID: PMC8549397 DOI: 10.1186/s12943-021-01423-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 09/11/2021] [Indexed: 01/18/2023] Open
Abstract
Autophagy is best known for its role in organelle and protein turnover, cell quality control, and metabolism. The autophagic machinery has, however, also adapted to enable protein trafficking and unconventional secretory pathways so that organelles (such as autophagosomes and multivesicular bodies) delivering cargo to lysosomes for degradation can change their mission from fusion with lysosomes to fusion with the plasma membrane, followed by secretion of the cargo from the cell. Some factors with key signalling functions do not enter the conventional secretory pathway but can be secreted in an autophagy-mediated manner.Positive clinical results of some autophagy inhibitors are encouraging. Nevertheless, it is becoming clear that autophagy inhibition, even within the same cancer type, can affect cancer progression differently. Even next-generation inhibitors of autophagy can have significant non-specific effects, such as impacts on endosome-related secretory pathways and secretion of extracellular vesicles (EVs). Many studies suggest that cancer cells release higher amounts of EVs compared to non-malignant cells, which makes the effect of autophagy inhibitors on EVs secretion highly important and attractive for anticancer therapy. In this review article, we discuss how different inhibitors of autophagy may influence the secretion of EVs and summarize the non-specific effects of autophagy inhibitors with a focus on endosome-related secretory pathways. Modulation of autophagy significantly impacts not only the quantity of EVs but also their content, which can have a deep impact on the resulting pro-tumourigenic or anticancer effect of autophagy inhibitors used in the antineoplastic treatment of solid cancers.
Collapse
Affiliation(s)
- Martina Raudenska
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
| | - Jan Balvan
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic
| | - Michal Masarik
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic.
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic.
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, CZ-625 00, Brno, Czech Republic.
- BIOCEV, First Faculty of Medicine, Charles University, Prumyslova 595, CZ-252 50, Vestec, Czech Republic.
- Center for Advanced Functional Nanorobots, Department of Inorganic Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology in Prague, Technická 5, CZ-166 28, Prague, Czech Republic.
| |
Collapse
|
15
|
Fei X, Li Z, Yang D, Kong X, Lu X, Shen Y, Li X, Xie S, Wang J, Zhao Y, Sun Y, Zhang J, Ye Z, Wang J, Cai Z. Neddylation of Coro1a determines the fate of multivesicular bodies and biogenesis of extracellular vesicles. J Extracell Vesicles 2021; 10:e12153. [PMID: 34623756 PMCID: PMC8500273 DOI: 10.1002/jev2.12153] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 09/15/2021] [Accepted: 09/19/2021] [Indexed: 12/01/2022] Open
Abstract
Multivesicular bodies (MVBs) fuse with not only the plasma membranes to release extracellular vesicles (EVs) but also lysosomes for degradation. Rab7 participates in the lysosomal targeting of MVBs. However, the proteins on MVB that directly bind Rab7, causing MVB recruitment of Rab7 remain unidentified. Here, we show that Coro1a undergoes neddylation modification at K233 by TRIM4. Neddylated Coro1a is associated with the MVB membrane and facilitates MVB recruitment and activation of Rab7 by directly binding Rab7. Subsequently, MVBs are targeted to lysosomes for degradation in a Rab7-dependent manner, leading to reduced EV secretion. Furthermore, a decrease in neddylated Coro1a enhances the production of tumour EVs, thereby promoting tumour progression, indicating that neddylated Coro1a is an ideal target for the regulation of EV biogenesis. Altogether, our data identify a novel substrate of neddylation and reveal an unknown mechanism for MVB recruitment of Rab7, thus providing new insight into the regulation of EV biogenesis.
Collapse
Affiliation(s)
- Xuefeng Fei
- Institute of Immunology, Department of Orthopaedics of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhijie Li
- Institute of Immunology, Department of Orthopaedics of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Diya Yang
- Xinyuan Institute of Medicine and Biotechnology, School of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, China
| | - Xianghui Kong
- Institute of Immunology, Department of Orthopaedics of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xinliang Lu
- Institute of Immunology, Department of Orthopaedics of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yingying Shen
- Institute of Immunology, Department of Orthopaedics of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xu Li
- School of Life Science, Westlake University, Hangzhou, China
| | - Shaofang Xie
- School of Life Science, Westlake University, Hangzhou, China
| | - Jiaoli Wang
- Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang University Cancer Centre, Hangzhou, China
| | - Yongchao Zhao
- Cancer Institute of the Second Affiliated Hospital, and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Yi Sun
- Cancer Institute of the Second Affiliated Hospital, and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Jing Zhang
- Department of Pathology of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhaoming Ye
- Department of Orthopaedics, Musculoskeletal Tumour Centre of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jianli Wang
- Institute of Immunology, Bone Marrow Transplantation Centre of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Haematology, Zhejiang University & Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, China
| | - Zhijian Cai
- Institute of Immunology, Department of Orthopaedics of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| |
Collapse
|
16
|
Selyunin AS, Nieves-Merced K, Li D, McHardy SF, Mukhopadhyay S. Tamoxifen Derivatives Alter Retromer-Dependent Endosomal Tubulation and Sorting to Block Retrograde Trafficking of Shiga Toxins. Toxins (Basel) 2021; 13:toxins13060424. [PMID: 34203879 PMCID: PMC8232625 DOI: 10.3390/toxins13060424] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/09/2021] [Accepted: 06/11/2021] [Indexed: 12/19/2022] Open
Abstract
Shiga toxin 1 and 2 (STx1 and STx2) undergo retrograde trafficking to reach the cytosol of cells where they target ribosomes. As retrograde trafficking is essential for disease, inhibiting STx1/STx2 trafficking is therapeutically promising. Recently, we discovered that the chemotherapeutic drug tamoxifen potently inhibits the trafficking of STx1/STx2 at the critical early endosome-to-Golgi step. We further reported that the activity of tamoxifen against STx1/STx2 is independent of its selective estrogen receptor modulator (SERM) property and instead depends on its weakly basic chemical nature, which allows tamoxifen to increase endolysosomal pH and alter the recruitment of retromer to endosomes. The goal of the current work was to obtain a better understanding of the mechanism of action of tamoxifen against the more disease-relevant toxin STx2, and to differentiate between the roles of changes in endolysosomal pH and retromer function. Structure activity relationship (SAR) analyses revealed that a weakly basic amine group was essential for anti-STx2 activity. However, ability to deacidify endolysosomes was not obligatorily necessary because a tamoxifen derivative that did not increase endolysosomal pH exerted reduced, but measurable, activity. Additional assays demonstrated that protective derivatives inhibited the formation of retromer-dependent, Golgi-directed, endosomal tubules, which mediate endosome-to-Golgi transport, and the sorting of STx2 into these tubules. These results identify retromer-mediated endosomal tubulation and sorting to be fundamental processes impacted by tamoxifen; provide an explanation for the inhibitory effect of tamoxifen on STx2; and have important implications for the therapeutic use of tamoxifen, including its development for treating Shiga toxicosis.
Collapse
Affiliation(s)
- Andrey S. Selyunin
- Division of Pharmacology and Toxicology, Institute for Neuroscience, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; (A.S.S.); (D.L.)
| | - Karinel Nieves-Merced
- Center for Innovative Drug Discovery, Department of Chemistry, University of Texas San Antonio, San Antonio, TX 78249, USA;
| | - Danyang Li
- Division of Pharmacology and Toxicology, Institute for Neuroscience, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; (A.S.S.); (D.L.)
| | - Stanton F. McHardy
- Center for Innovative Drug Discovery, Department of Chemistry, University of Texas San Antonio, San Antonio, TX 78249, USA;
- Correspondence: (S.F.M.); (S.M.)
| | - Somshuvra Mukhopadhyay
- Division of Pharmacology and Toxicology, Institute for Neuroscience, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; (A.S.S.); (D.L.)
- Correspondence: (S.F.M.); (S.M.)
| |
Collapse
|
17
|
Chadwick SR, Grinstein S, Freeman SA. From the inside out: Ion fluxes at the centre of endocytic traffic. Curr Opin Cell Biol 2021; 71:77-86. [PMID: 33706237 DOI: 10.1016/j.ceb.2021.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/19/2021] [Accepted: 02/04/2021] [Indexed: 12/15/2022]
Abstract
Endocytic traffic is a complex and elegant operation involving cargo sorting, membrane budding and tubulation, generation of force, and the formation of organellar contacts. The role of specific proteins and lipids in these processes has been studied extensively. By comparison, precious little is understood about the contribution of the endocytic fluid to these events, despite much evidence that alteration of the contents can severely affect membrane traffic along the endocytic pathway. In particular, it has long been appreciated that dissipation of ionic gradients arrests endosome-to-lysosome maturation. How cells sense inorganic ions and transmit this information have remained largely enigmatic. Herein, we review the experimental findings that reveal an intimate association between luminal ions, their transport, and endocytic traffic. We then discuss the ionic sensors and the mechanisms proposed to convert ion concentrations into protein-based trafficking events, highlighting the current paucity of convincing explanations.
Collapse
Affiliation(s)
- Sarah R Chadwick
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON, M5G 0A4, Canada
| | - Sergio Grinstein
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON, M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Canada.
| | - Spencer A Freeman
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, 686 Bay Street, 19-9800, Toronto, ON, M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Canada.
| |
Collapse
|
18
|
Two-pore and TRPML cation channels: Regulators of phagocytosis, autophagy and lysosomal exocytosis. Pharmacol Ther 2020; 220:107713. [PMID: 33141027 DOI: 10.1016/j.pharmthera.2020.107713] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/19/2020] [Indexed: 02/07/2023]
Abstract
The old Greek saying "Panta Rhei" ("everything flows") is true for all life and all living things in general. It also becomes nicely evident when looking closely into cells. There, material from the extracellular space is taken up by endocytic processes and transported to endosomes where it is sorted either for recycling or degradation. Cargo is also packaged for export through exocytosis involving the Golgi network, lysosomes and other organelles. Everything in this system is in constant motion and many proteins are necessary to coordinate transport along the different intracellular pathways to avoid chaos. Among these proteins are ion channels., in particular TRPML channels (mucolipins) and two-pore channels (TPCs) which reside on endosomal and lysosomal membranes to speed up movement between organelles, e.g. by regulating fusion and fission; they help readjust pH and osmolarity changes due to such processes, or they promote exocytosis of export material. Pathophysiologically, these channels are involved in neurodegenerative, metabolic, retinal and infectious diseases, cancer, pigmentation defects, and immune cell function, and thus have been proposed as novel pharmacological targets, e.g. for the treatment of lysosomal storage disorders, Duchenne muscular dystrophy, or different types of cancer. Here, we discuss the similarities but also differences of TPCs and TRPMLs in regulating phagocytosis, autophagy and lysosomal exocytosis, and we address the contradictions and open questions in the field relating to the roles TPCs and TRPMLs play in these different processes.
Collapse
|
19
|
Targeting the Early Endosome-to-Golgi Transport of Shiga Toxins as a Therapeutic Strategy. Toxins (Basel) 2020; 12:toxins12050342. [PMID: 32456007 PMCID: PMC7290323 DOI: 10.3390/toxins12050342] [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: 05/02/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 02/07/2023] Open
Abstract
Shiga toxin (STx) produced by Shigella and closely related Shiga toxin 1 and 2 (STx1 and STx2) synthesized by Shiga toxin-producing Escherichia coli (STEC) are bacterial AB5 toxins. All three toxins target kidney cells and may cause life-threatening renal disease. While Shigella infections can be treated with antibiotics, resistance is increasing. Moreover, antibiotic therapy is contraindicated for STEC, and there are no definitive treatments for STEC-induced disease. To exert cellular toxicity, STx, STx1, and STx2 must undergo retrograde trafficking to reach their cytosolic target, ribosomes. Direct transport from early endosomes to the Golgi apparatus is an essential step that allows the toxins to bypass degradative late endosomes and lysosomes. The essentiality of this transport step also makes it an ideal target for the development of small-molecule inhibitors of toxin trafficking as potential therapeutics. Here, we review the recent advances in understanding the molecular mechanisms of the early endosome-to-Golgi transport of STx, STx1, and STx2, as well as the development of small-molecule inhibitors of toxin trafficking that act at the endosome/Golgi interface.
Collapse
|
20
|
Ilie A, Boucher A, Park J, Berghuis AM, McKinney RA, Orlowski J. Assorted dysfunctions of endosomal alkali cation/proton exchanger SLC9A6 variants linked to Christianson syndrome. J Biol Chem 2020; 295:7075-7095. [PMID: 32277048 PMCID: PMC7242699 DOI: 10.1074/jbc.ra120.012614] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 04/07/2020] [Indexed: 12/15/2022] Open
Abstract
Genetic screening has identified numerous variants of the endosomal solute carrier family 9 member A6 (SLC9A6)/(Na+,K+)/H+ exchanger 6 (NHE6) gene that cause Christianson syndrome, a debilitating X-linked developmental disorder associated with a range of neurological, somatic, and behavioral symptoms. Many of these variants cause complete loss of NHE6 expression, but how subtler missense substitutions or nonsense mutations that partially truncate its C-terminal cytoplasmic regulatory domain impair NHE6 activity and endosomal function are poorly understood. Here, we describe the molecular and cellular consequences of six unique mutations located in the N-terminal cytoplasmic segment (A9S), the membrane ion translocation domain (L188P and G383D), and the C-terminal regulatory domain (E547*, R568Q, and W570*) of human NHE6 that purportedly cause disease. Using a heterologous NHE6-deficient cell expression system, we show that the biochemical, catalytic, and cellular properties of the A9S and R568Q variants were largely indistinguishable from those of the WT transporter, which obscured their disease significance. By contrast, the L188P, G383D, E547*, and W570* mutants exhibited variable deficiencies in biosynthetic post-translational maturation, membrane sorting, pH homeostasis in recycling endosomes, and cargo trafficking, and they also triggered apoptosis. These findings broaden our understanding of the molecular dysfunctions of distinct NHE6 variants associated with Christianson syndrome.
Collapse
Affiliation(s)
- Alina Ilie
- Department of Physiology, McGill University, Montreal, Quebec H3G 0B1, Canada
| | - Annie Boucher
- Department of Physiology, McGill University, Montreal, Quebec H3G 0B1, Canada
| | - Jaeok Park
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 0B1, Canada
| | | | - R Anne McKinney
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec H3G 0B1, Canada
| | - John Orlowski
- Department of Physiology, McGill University, Montreal, Quebec H3G 0B1, Canada
| |
Collapse
|
21
|
Joshi B, de Beer MA, Giepmans BNG, Zuhorn IS. Endocytosis of Extracellular Vesicles and Release of Their Cargo from Endosomes. ACS NANO 2020; 14:4444-4455. [PMID: 32282185 PMCID: PMC7199215 DOI: 10.1021/acsnano.9b10033] [Citation(s) in RCA: 268] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/13/2020] [Indexed: 05/22/2023]
Abstract
Extracellular vesicles (EVs), such as exosomes, can mediate long-distance communication between cells by delivering biomolecular cargo. It is speculated that EVs undergo back-fusion at multivesicular bodies (MVBs) in recipient cells to release their functional cargo. However, direct evidence is lacking. Tracing the cellular uptake of EVs with high resolution as well as acquiring direct evidence for the release of EV cargo is challenging mainly because of technical limitations. Here, we developed an analytical methodology, combining state-of-the-art molecular tools and correlative light and electron microscopy, to identify the intracellular site for EV cargo release. GFP was loaded inside EVs through the expression of GFP-CD63, a fusion of GFP to the cytosolic tail of CD63, in EV producer cells. In addition, we genetically engineered a cell line which expresses anti-GFP fluobody that specifically recognizes the EV cargo (GFP). Incubation of anti-GFP fluobody-expressing cells with GFP-CD63 EVs resulted in the formation of fluobody punctae, designating cytosolic exposure of GFP. Endosomal damage was not observed in EV acceptor cells. Ultrastructural analysis of the underlying structures at GFP/fluobody double-positive punctae demonstrated that EV cargo release occurs from endosomes/lysosomes. Finally, we show that neutralization of endosomal pH and cholesterol accumulation in endosomes leads to blockage of EV cargo exposure. In conclusion, we report that a fraction of internalized EVs fuse with the limiting membrane of endosomes/lysosomes in an acidification-dependent manner, which results in EV cargo exposure to the cell cytosol.
Collapse
Affiliation(s)
- Bhagyashree
S. Joshi
- Department
of Biomedical Engineering, University of
Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands
| | - Marit A. de Beer
- Department
of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands
| | - Ben N. G. Giepmans
- Department
of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands
| | - Inge S. Zuhorn
- Department
of Biomedical Engineering, University of
Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands
| |
Collapse
|
22
|
Strauch BM, Hubele W, Hartwig A. Impact of Endocytosis and Lysosomal Acidification on the Toxicity of Copper Oxide Nano- and Microsized Particles: Uptake and Gene Expression Related to Oxidative Stress and the DNA Damage Response. NANOMATERIALS 2020; 10:nano10040679. [PMID: 32260290 PMCID: PMC7221514 DOI: 10.3390/nano10040679] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/23/2020] [Accepted: 03/30/2020] [Indexed: 01/04/2023]
Abstract
The toxicity of the copper oxide nanoparticles (CuO NP) has been attributed to the so-called "Trojan horse"-type mechanism, relying on the particle uptake and extensive intracellular release of copper ions, due to acidic pH in the lysosomes. Nevertheless, a clear distinction between extra- and intracellular-mediated effects is still missing. Therefore, the impact of the endocytosis inhibitor hydroxy-dynasore (OH-dyn), as well as bafilomycin A1 (bafA1), inhibiting the vacuolar type H+-ATPase (V-ATPase), on the cellular toxicity of nano- and microsized CuO particles, was investigated in BEAS 2 B cells. Selected endpoints were cytotoxicity, copper uptake, glutathione (GSH) levels, and the transcriptional DNA damage and (oxidative) stress response using the high-throughput reverse transcription quantitative polymerase chain reaction (RT-qPCR). OH-dyn markedly reduced intracellular copper accumulation in the cases of CuO NP and CuO MP; the modulation of gene expression, induced by both particle types affecting especially HMOX1, HSPA1A, MT1X, SCL30A1, IL8 and GADD45A, were completely abolished. BafA1 lowered the intracellular copper concentration in case of CuO NP and strongly reduced transcriptional changes, while any CuO MP-mediated effects were not affected by bafA1. In conclusion, the toxicity of CuO NP depended almost exclusively upon dynamin-dependent endocytosis and the intracellular release of redox-active copper ions due to lysosomal acidification, while particle interactions with cellular membranes appeared to be not relevant.
Collapse
|
23
|
Kobayashi T, Piao W, Takamura T, Kori H, Miyachi H, Kitano S, Iwamoto Y, Yamada M, Imayoshi I, Shioda S, Ballabio A, Kageyama R. Enhanced lysosomal degradation maintains the quiescent state of neural stem cells. Nat Commun 2019; 10:5446. [PMID: 31784517 PMCID: PMC6884460 DOI: 10.1038/s41467-019-13203-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 10/28/2019] [Indexed: 01/08/2023] Open
Abstract
Quiescence is important for sustaining neural stem cells (NSCs) in the adult brain over the lifespan. Lysosomes are digestive organelles that degrade membrane receptors after they undergo endolysosomal membrane trafficking. Enlarged lysosomes are present in quiescent NSCs (qNSCs) in the subventricular zone of the mouse brain, but it remains largely unknown how lysosomal function is involved in the quiescence. Here we show that qNSCs exhibit higher lysosomal activity and degrade activated EGF receptor by endolysosomal degradation more rapidly than proliferating NSCs. Chemical inhibition of lysosomal degradation in qNSCs prevents degradation of signaling receptors resulting in exit from quiescence. Furthermore, conditional knockout of TFEB, a lysosomal master regulator, delays NSCs quiescence in vitro and increases NSC proliferation in the dentate gyrus of mice. Taken together, our results demonstrate that enhanced lysosomal degradation is an important regulator of qNSC maintenance. It remains unclear why quiescent neural stem cells (qNSCs) in the subventricular zone of the mouse brain have enlarged lysosomes. Here, authors demonstrate that qNSCs exhibit higher lysosomal activity and degrade activated EGF receptor by endolysosomal degradation more rapidly than proliferating NSCs, which prevents the NSC exit from quiescence.
Collapse
Affiliation(s)
- Taeko Kobayashi
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan. .,Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan. .,Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan.
| | - Wenhui Piao
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan
| | - Toshiya Takamura
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan
| | - Hiroshi Kori
- Department of Complexity Science and Engineering, University of Tokyo, Tokyo, 277-8561, Japan
| | - Hitoshi Miyachi
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan
| | - Satsuki Kitano
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan
| | - Yumiko Iwamoto
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan
| | - Mayumi Yamada
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan.,Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto, 606-8501, Japan
| | - Itaru Imayoshi
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan.,Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto, 606-8501, Japan
| | - Seiji Shioda
- Peptide Drug Innovation, Global Research Center for Innovative Life Science (GRIL), Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo, 142-8501, Japan
| | - Andrea Ballabio
- Telethon Institute of Genetics and Medicine, Via Campi Flegrei 34, 80078, Pozzuoli, NA, Italy
| | - Ryoichiro Kageyama
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan. .,Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan. .,Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan. .,Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto, 606-8501, Japan.
| |
Collapse
|
24
|
Wheeler S, Sillence DJ. Niemann-Pick type C disease: cellular pathology and pharmacotherapy. J Neurochem 2019; 153:674-692. [PMID: 31608980 DOI: 10.1111/jnc.14895] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/10/2019] [Accepted: 09/15/2019] [Indexed: 12/22/2022]
Abstract
Niemann-Pick type C disease (NPCD) was first described in 1914 and affects approximately 1 in 150 000 live births. It is characterized clinically by diverse symptoms affecting liver, spleen, motor control, and brain; premature death invariably results. Its molecular origins were traced, as late as 1997, to a protein of late endosomes and lysosomes which was named NPC1. Mutation or absence of this protein leads to accumulation of cholesterol in these organelles. In this review, we focus on the intracellular events that drive the pathology of this disease. We first introduce endocytosis, a much-studied area of dysfunction in NPCD cells, and survey the various ways in which this process malfunctions. We briefly consider autophagy before attempting to map the more complex pathways by which lysosomal cholesterol storage leads to protein misregulation, mitochondrial dysfunction, and cell death. We then briefly introduce the metabolic pathways of sphingolipids (as these emerge as key species for treatment) and critically examine the various treatment approaches that have been attempted to date.
Collapse
Affiliation(s)
- Simon Wheeler
- School of Pharmacy, De Montfort University, The Gateway, Leicester, UK
| | - Dan J Sillence
- School of Pharmacy, De Montfort University, The Gateway, Leicester, UK
| |
Collapse
|
25
|
Kerner-Rossi M, Gulinello M, Walkley S, Dobrenis K. Pathobiology of Christianson syndrome: Linking disrupted endosomal-lysosomal function with intellectual disability and sensory impairments. Neurobiol Learn Mem 2019; 165:106867. [PMID: 29772390 PMCID: PMC6235725 DOI: 10.1016/j.nlm.2018.05.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 05/04/2018] [Accepted: 05/12/2018] [Indexed: 11/18/2022]
Abstract
Christianson syndrome (CS) is a recently described rare neurogenetic disorder presenting early in life with a broad range of neurological symptoms, including severe intellectual disability with nonverbal status, hyperactivity, epilepsy, and progressive ataxia due to cerebellar atrophy. CS is due to loss-of-function mutations in SLC9A6, encoding NHE6, a sodium-hydrogen exchanger involved in the regulation of early endosomal pH. Here we review what is currently known about the neuropathogenesis of CS, based on insights from experimental models, which to date have focused on mechanisms that affect the CNS, specifically the brain. In addition, parental reports of sensory disturbances in their children with CS, including an apparent insensitivity to pain, led us to explore sensory function and related neuropathology in Slc9a6 KO mice. We present new data showing sensory deficits in Slc9a6 KO mice, which had reduced behavioral responses to noxious thermal and mechanical stimuli (Hargreaves and Von Frey assays, respectively) compared to wild type (WT) littermates. Immunohistochemical and ultrastructural analysis of the spinal cord and peripheral nervous system revealed intracellular accumulation of the glycosphingolipid GM2 ganglioside in KO but not WT mice. This cellular storage phenotype was most abundant in neurons of lamina I-II of the dorsal horn, a major relay site in the processing of painful stimuli. Spinal cords of KO mice also exhibited changes in astroglial and microglial populations throughout the gray matter suggestive of a neuroinflammatory process. Our findings establish the Slc9a6 KO mouse as a relevant tool for studying the sensory deficits in CS, and highlight selective vulnerabilities in relevant cell populations that may contribute to this phenotype. How NHE6 loss of function leads to such a multifaceted neurological syndrome is still undefined, and it is likely that NHE6 is involved with many cellular processes critical to normal nervous system development and function. In addition, the sensory issues exhibited by Slc9a6 KO mice, in combination with our neuropathological findings, are consistent with NHE6 loss of function impacting the entire nervous system. Sensory dysfunction in intellectually disabled individuals is challenging to assess and may impair patient safety and quality of life. Further mechanistic studies of the neurological impairments underlying CS and other genetic intellectual disability disorders must also take into account mechanisms affecting broader nervous system function in order to understand the full range of associated disabilities.
Collapse
Affiliation(s)
- Mallory Kerner-Rossi
- Dominick P. Purpura Dept. of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Maria Gulinello
- Dominick P. Purpura Dept. of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA; IDDRC Behavioral Core Facility, Neuroscience Department, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Steven Walkley
- Dominick P. Purpura Dept. of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Kostantin Dobrenis
- Dominick P. Purpura Dept. of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| |
Collapse
|
26
|
Marrero-Hernández S, Márquez-Arce D, Cabrera-Rodríguez R, Estévez-Herrera J, Pérez-Yanes S, Barroso-González J, Madrid R, Machado JD, Blanco J, Valenzuela-Fernández A. HIV-1 Nef Targets HDAC6 to Assure Viral Production and Virus Infection. Front Microbiol 2019; 10:2437. [PMID: 31736889 PMCID: PMC6831784 DOI: 10.3389/fmicb.2019.02437] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/10/2019] [Indexed: 12/11/2022] Open
Abstract
HIV Nef is a central auxiliary protein in HIV infection and pathogenesis. Our results indicate that HDAC6 promotes the aggresome/autophagic degradation of the viral polyprotein Pr55Gag to inhibit HIV-1 production. Nef counteracts this antiviral activity of HDAC6 by inducing its degradation and subsequently stabilizing Pr55Gag and Vif viral proteins. Nef appears to neutralize HDAC6 by an acidic/endosomal-lysosomal processing and does not need the downregulation function, since data obtained with the non-associated cell-surface Nef-G2A mutant - the cytoplasmic location of HDAC6 - together with studies with chemical inhibitors and other Nef mutants, point to this direction. Hence, the polyproline rich region P72xxP75 (69-77 aa) and the di-Leucin motif in the Nef-ExxxLL160-165 sequence of Nef, appear to be responsible for HDAC6 clearance and, therefore, required for this novel Nef proviral function. Nef and Nef-G2A co-immunoprecipitate with HDAC6, whereas the Nef-PPAA mutant showed a reduced interaction with the anti-HIV-1 enzyme. Thus, the P72xxP75 motif appears to be responsible, directly or indirectly, for the interaction of Nef with HDAC6. Remarkably, by neutralizing HDAC6, Nef assures Pr55Gag location and aggregation at plasma membrane, as observed by TIRFM, promotes viral egress, and enhances the infectivity of viral particles. Consequently, our results suggest that HDAC6 acts as an anti-HIV-1 restriction factor, limiting viral production and infection by targeting Pr55Gag and Vif. This function is counteracted by functional HIV-1 Nef, in order to assure viral production and infection capacities. The interplay between HIV-1 Nef and cellular HDAC6 may determine viral infection and pathogenesis, representing both molecules as key targets to battling HIV.
Collapse
Affiliation(s)
- Sara Marrero-Hernández
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Daniel Márquez-Arce
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Romina Cabrera-Rodríguez
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Judith Estévez-Herrera
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Silvia Pérez-Yanes
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Jonathan Barroso-González
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Ricardo Madrid
- BioAssays SL, Campus de Cantoblanco, Madrid, Spain.,Departmento de Genética, Fisiología y Microbiología, Facultad de Biología, Universidad Complutense de Madrid (UCM), Madrid, Spain
| | - José-David Machado
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Julià Blanco
- AIDS Research Institute IrsiCaixa, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Badalona, Spain.,Universitat de Vic-Central de Catalunya, UVIC-UCC, Catalonia, Spain
| | - Agustín Valenzuela-Fernández
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| |
Collapse
|
27
|
Progeny Varicella-Zoster Virus Capsids Exit the Nucleus but Never Undergo Secondary Envelopment during Autophagic Flux Inhibition by Bafilomycin A1. J Virol 2019; 93:JVI.00505-19. [PMID: 31217243 PMCID: PMC6694825 DOI: 10.1128/jvi.00505-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 06/12/2019] [Indexed: 12/31/2022] Open
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that lacks the herpesviral neurovirulence protein ICP34.5. The underlying hypothesis of this project was that inhibitors of autophagy reduce VZV infectivity. We selected the vacuolar proton ATPase inhibitor bafilomycin A1 for analysis because of its well-known antiautophagy property of impeding acidification during the late stage of autophagic flux. We documented that bafilomycin treatment from 48 to 72 h postinfection lowered VZV titers substantially (P ≤ 0.008). Because we were unable to define the site of the block in the infectious cycle by confocal microscopy, we turned to electron microscopy. Capsids were observed in the nucleus, in the perinuclear space, and in the cytoplasm adjacent to Golgi apparatus vesicles. Many of the capsids had an aberrant appearance, as has been observed previously in infections not treated with bafilomycin. In contrast to prior untreated infections, however, secondary envelopment of capsids was not seen in the trans-Golgi network, nor were prototypical enveloped particles with capsids (virions) seen in cytoplasmic vesicles after bafilomycin treatment. Instead, multiple particles with varying diameters without capsids (light particles) were seen in large virus assembly compartments near the disorganized Golgi apparatus. Bafilomycin treatment also led to increased numbers of multivesicular bodies in the cytoplasm, some of which contained remnants of the Golgi apparatus. In summary, we have defined a previously unrecognized property of bafilomycin whereby it disrupted the site of secondary envelopment of VZV capsids by altering the pH of the trans-Golgi network and thereby preventing the correct formation of virus assembly compartments.IMPORTANCE This study of VZV assembly in the presence of bafilomycin A1 emphasizes the importance of the Golgi apparatus/trans-Golgi network as a platform in the alphaherpesvirus life cycle. We have previously shown that VZV induces levels of autophagy far above the basal levels of autophagy in human skin, a major site of VZV assembly. The current study documented that bafilomycin treatment led to impaired assembly of VZV capsids after primary envelopment/de-envelopment but before secondary reenvelopment. This VZV study also complemented prior herpes simplex virus 1 and pseudorabies virus studies investigating two other inhibitors of endoplasmic reticulum (ER)/Golgi apparatus function: brefeldin A and monensin. Studies with porcine herpesvirus demonstrated that primary enveloped particles accumulated in the perinuclear space in the presence of brefeldin A, while studies with herpes simplex virus 1 documented an impaired secondary assembly of enveloped viral particles in the presence of monensin.
Collapse
|
28
|
Jiang LQ, Wang TY, Wang Y, Wang ZY, Bai YT. Co-disposition of chitosan nanoparticles by multi types of hepatic cells and their subsequent biological elimination: the mechanism and kinetic studies at the cellular and animal levels. Int J Nanomedicine 2019; 14:6035-6060. [PMID: 31534335 PMCID: PMC6681437 DOI: 10.2147/ijn.s208496] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 07/03/2019] [Indexed: 12/12/2022] Open
Abstract
Background: The clearance of nanomaterials (NMs) from the liver is essential for clinical safety, and their hepatic clearance is primarily determined by the co-disposition process of various types of hepatic cells. Studies of this process and the subsequent clearance routes are urgently needed for organic NMs, which are used as drug carriers more commonly than the inorganic ones. Materials and methods: In this study, the co-disposition of chitosan-based nanoparticles (CsNps) by macrophages and hepatocytes at both the cellular and animal levels as well as their subsequent biological elimination were investigated. RAW264.7 and Hepa1-6 cells were used as models of Kupffer cells and hepatocytes, respectively. Results: The cellular studies showed that CsNps released from RAW264.7 cells could enter Hepa1-6 cells through both clathrin- and caveolin-mediated endocytosis. The transport from Kupffer cells to hepatocytes was also studied in mice, and it was observed that most CsNps localized to the hepatocytes after intravenous injection. Following the distribution in hepatocytes, the hepatobiliary-fecal excretion route was shown to be the primary elimination route for CsNps, besides the kidney-urinary excretion route. The elimination of CsNps in mice was a lengthy process, with a half time of about 2 months. Conclusion: The demonstration in this study of the transport of CsNps from macrophages to hepatocytes and the subsequent hepatobiliary-fecal excretion provides basic information for the future development and clinical application of NMs.
Collapse
Affiliation(s)
- Li-Qun Jiang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Ting-Yu Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Yun Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Zi-Yao Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Yu-Ting Bai
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, China
- School of Stomatology, Xuzhou Medical University, Xuzhou, China
| |
Collapse
|
29
|
Zhang X, Castanotto D, Liu X, Shemi A, Stein CA. Ammonium and arsenic trioxide are potent facilitators of oligonucleotide function when delivered by gymnosis. Nucleic Acids Res 2019. [PMID: 29522198 DOI: 10.1093/nar/gky150] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Oligonucleotide (ON) concentrations employed for therapeutic applications vary widely, but in general are high enough to raise significant concerns for off target effects and cellular toxicity. However, lowering ON concentrations reduces the chances of a therapeutic response, since typically relatively small amounts of ON are taken up by targeted cells in tissue culture. It is therefore imperative to identify new strategies to improve the concentration dependence of ON function. In this work, we have identified ammonium ion (NH4+) as a non-toxic potent enhancer of ON activity in the nucleus and cytoplasm following delivery by gymnosis. NH4+ is a metabolite that has been extensively employed as diuretic, expectorant, for the treatment of renal calculi and in a variety of other diseases. Enhancement of function can be found in attached and suspension cells, including in difficult-to-transfect Jurkat T and CEM T cells. We have also demonstrated that NH4+ can synergistically interact with arsenic trioxide (arsenite) to further promote ON function without producing any apparent increased cellular toxicity. These small, inexpensive, widely distributed molecules could be useful not only in laboratory experiments but potentially in therapeutic ON-based combinatorial strategy for clinical applications.
Collapse
Affiliation(s)
- Xiaowei Zhang
- Department of Medical Oncology and Experimental Therapeutics, City of Hope, 1500 E. Duarte Rd., Duarte, CA 91010, USA
| | - Daniela Castanotto
- Department of Medical Oncology and Experimental Therapeutics, City of Hope, 1500 E. Duarte Rd., Duarte, CA 91010, USA
| | - Xueli Liu
- Department of Information Science, City of Hope, 1500 E. Duarte Rd., Duarte, CA 91010, USA
| | - Amotz Shemi
- Silenseed, 2 HaMa'ayan Street, Modi'in Technology Park, Modi'in 7177871, Israel
| | - Cy A Stein
- Department of Medical Oncology and Experimental Therapeutics, City of Hope, 1500 E. Duarte Rd., Duarte, CA 91010, USA
| |
Collapse
|
30
|
Wheeler S, Haberkant P, Bhardwaj M, Tongue P, Ferraz MJ, Halter D, Sprong H, Schmid R, Aerts JM, Sullo N, Sillence DJ. Cytosolic glucosylceramide regulates endolysosomal function in Niemann-Pick type C disease. Neurobiol Dis 2019; 127:242-252. [DOI: 10.1016/j.nbd.2019.03.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 03/06/2019] [Accepted: 03/09/2019] [Indexed: 12/22/2022] Open
|
31
|
Selyunin AS, Hutchens S, McHardy SF, Mukhopadhyay S. Tamoxifen blocks retrograde trafficking of Shiga toxin 1 and 2 and protects against lethal toxicosis. Life Sci Alliance 2019; 2:2/3/e201900439. [PMID: 31243048 PMCID: PMC6599968 DOI: 10.26508/lsa.201900439] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 06/06/2019] [Accepted: 06/07/2019] [Indexed: 12/18/2022] Open
Abstract
This study reports an unexpected role of late endosome–lysosome fusion in early endosome-to-Golgi trafficking of Shiga toxins and identifies tamoxifen to be a potent inhibitor of Shiga toxicosis. Shiga toxin 1 (STx1) and 2 (STx2), produced by Shiga toxin–producing Escherichia coli, cause lethal untreatable disease. The toxins invade cells via retrograde trafficking. Direct early endosome-to-Golgi transport allows the toxins to evade degradative late endosomes. Blocking toxin trafficking, particularly at the early endosome-to-Golgi step, is appealing, but transport mechanisms of the more disease-relevant STx2 are unclear. Using data from a genome-wide siRNA screen, we discovered that disruption of the fusion of late endosomes, but not autophagosomes, with lysosomes blocked the early endosome-to-Golgi transport of STx2. A subsequent screen of clinically approved lysosome-targeting drugs identified tamoxifen (TAM) to be a potent inhibitor of the trafficking and toxicity of STx1 and STx2 in cells. The protective effect was independent of estrogen receptors but dependent on the weak base property of TAM, which allowed TAM to increase endolysosomal pH and alter endosomal dynamics. Importantly, TAM treatment enhanced survival of mice injected with a lethal dose of STx1 or STx2. Thus, it may be possible to repurpose TAM for treating Shiga toxin–producing E. coli infections.
Collapse
Affiliation(s)
- Andrey S Selyunin
- Division of Pharmacology and Toxicology, College of Pharmacy; Institute for Cellular and Molecular Biology; and Institute for Neuroscience, The University of Texas at Austin, Austin, TX, USA
| | - Steven Hutchens
- Division of Pharmacology and Toxicology, College of Pharmacy; Institute for Cellular and Molecular Biology; and Institute for Neuroscience, The University of Texas at Austin, Austin, TX, USA
| | - Stanton F McHardy
- Center for Innovative Drug Discovery, Department of Chemistry, University of Texas San Antonio, San Antonio, TX, USA
| | - Somshuvra Mukhopadhyay
- Division of Pharmacology and Toxicology, College of Pharmacy; Institute for Cellular and Molecular Biology; and Institute for Neuroscience, The University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
32
|
The Small GTPase Arf6: An Overview of Its Mechanisms of Action and of Its Role in Host⁻Pathogen Interactions and Innate Immunity. Int J Mol Sci 2019; 20:ijms20092209. [PMID: 31060328 PMCID: PMC6539230 DOI: 10.3390/ijms20092209] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/26/2019] [Accepted: 04/27/2019] [Indexed: 12/15/2022] Open
Abstract
The small GTase Arf6 has several important functions in intracellular vesicular trafficking and regulates the recycling of different types of cargo internalized via clathrin-dependent or -independent endocytosis. It activates the lipid modifying enzymes PIP 5-kinase and phospholipase D, promotes actin polymerization, and affects several functionally distinct processes in the cell. Arf6 is used for the phagocytosis of pathogens and can be directly or indirectly targeted by various pathogens to block phagocytosis or induce the uptake of intracellular pathogens. Arf6 is also used in the signaling of Toll-like receptors and in the activation of NADPH oxidases. In this review, we first give an overview of the different roles and mechanisms of action of Arf6 and then focus on its role in innate immunity and host–pathogen interactions.
Collapse
|
33
|
Abstract
Many past and recent advances in the field of iron metabolism have relied upon the discovery of divalent metal transporter 1, DMT1 in 1997. DMT1 is the major iron transporter and contributes non-heme iron uptake in most types of cell. Each DMT1 isoform exhibits different expression patterns in cell-type specificity and distinct subcellular distribution, which enables cells to uptake both transferrin-bound and non-transferrin-bound irons efficiently. DMT1 expression is regulated by iron through the translational and degradation pathways to ensure iron homeostasis. It is considered that mammalian iron transporters including DMT1 cannot transport ferric iron but ferrous iron. Being reduced to ferrous state is likely to damage cells and tissues through the production of reactive oxygen species. Recently, iron chaperones have been identified, which can provide an answer to how ferrous iron is transported safely in cytosol. We summarize DMT1 expression depending on the types of cell or tissue and the function and mechanism of one of the iron chaperones, PCBP2.
Collapse
Affiliation(s)
- Izumi Yanatori
- Department of Biochemistry, Stanford University, School of Medicine, 279 Campus Drive, Stanford, CA 94305-5307, USA
| | - Fumio Kishi
- Hagi Public Health and Welfare Center, Yamaguchi Prefectural Government, 531-1 Emukai, Hagi, Yamaguchi 758-0041, Japan.
| |
Collapse
|
34
|
Chauhan AS, Kumar M, Chaudhary S, Dhiman A, Patidar A, Jakhar P, Jaswal P, Sharma K, Sheokand N, Malhotra H, Raje CI, Raje M. Trafficking of a multifunctional protein by endosomal microautophagy: linking two independent unconventional secretory pathways. FASEB J 2019; 33:5626-5640. [PMID: 30640524 DOI: 10.1096/fj.201802102r] [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] [Indexed: 02/06/2023]
Abstract
During physiologic stresses, like micronutrient starvation, infection, and cancer, the cytosolic moonlighting protein glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is trafficked to the plasma membrane (PM) and extracellular milieu (ECM). Our work demonstrates that GAPDH mobilized to the PM, and the ECM does not utilize the classic endoplasmic reticulum-Golgi route of secretion; instead, it is first selectively translocated into early and late endosomes from the cytosol via microautophagy. GAPDH recruited to this common entry point is subsequently delivered into multivesicular bodies, leading to its membrane trafficking through secretion via exosomes and secretory lysosomes. We present evidence that both pathways of GAPDH membrane trafficking are up-regulated upon iron starvation, potentially by mobilization of intracellular calcium. These pathways also play a role in clearance of misfolded intracellular polypeptide aggregates. Our findings suggest that cells build in redundancy for vital cellular pathways to maintain micronutrient homeostasis and prevent buildup of toxic intracellular misfolded protein refuse.-Chauhan, A. S., Kumar, M., Chaudhary, S., Dhiman, A., Patidar, A., Jakhar, P., Jaswal, P., Sharma, K., Sheokand, N., Malhotra, H., Raje, C. I., Raje. M. Trafficking of a multifunctional protein by endosomal microautophagy: linking two independent unconventional secretory pathways.
Collapse
Affiliation(s)
- Anoop Singh Chauhan
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Manoj Kumar
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Surbhi Chaudhary
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Asmita Dhiman
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Anil Patidar
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Priyanka Jakhar
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Pallavi Jaswal
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Kapil Sharma
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Navdeep Sheokand
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | - Himanshu Malhotra
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| | | | - Manoj Raje
- Institute of Microbial Technology, Council of Scientific and Industrial Research (CSIR), Chandigarh, India
| |
Collapse
|
35
|
Kissing S, Saftig P, Haas A. Vacuolar ATPase in phago(lyso)some biology. Int J Med Microbiol 2017; 308:58-67. [PMID: 28867521 DOI: 10.1016/j.ijmm.2017.08.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/28/2017] [Accepted: 08/23/2017] [Indexed: 12/23/2022] Open
Abstract
Many eukaryotic cells ingest extracellular particles in a process termed phagocytosis which entails the generation of a new intracellular compartment, the phagosome. Phagosomes change their composition over time and this maturation process culminates in their fusion with acidic, hydrolase-rich lysosomes. During the maturation process, degradation and, when applicable, killing of the cargo may ensue. Many of the events that are pathologically relevant depend on strong acidification of phagosomes by the 'vacuolar' ATPase (V-ATPase). This protein complex acidifies the lumen of some intracellular compartments at the expense of ATP hydrolysis. We discuss here the roles and importance of V-ATPase in intracellular trafficking, its distribution, inhibition and activities, its role in the defense against microorganisms and the counteractivities of pathogens.
Collapse
Affiliation(s)
- Sandra Kissing
- Institut für Biochemie, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany
| | - Paul Saftig
- Institut für Biochemie, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany.
| | - Albert Haas
- Institut für Zellbiologie, Friedrich-Wilhelms-Universität Bonn, Ulrich-Haberland-Str. 61A, D-53121 Bonn, Germany.
| |
Collapse
|
36
|
Zhao J, Beyrakhova K, Liu Y, Alvarez CP, Bueler SA, Xu L, Xu C, Boniecki MT, Kanelis V, Luo ZQ, Cygler M, Rubinstein JL. Molecular basis for the binding and modulation of V-ATPase by a bacterial effector protein. PLoS Pathog 2017; 13:e1006394. [PMID: 28570695 PMCID: PMC5469503 DOI: 10.1371/journal.ppat.1006394] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 06/13/2017] [Accepted: 05/01/2017] [Indexed: 12/16/2022] Open
Abstract
Intracellular pathogenic bacteria evade the immune response by replicating within host cells. Legionella pneumophila, the causative agent of Legionnaires’ Disease, makes use of numerous effector proteins to construct a niche supportive of its replication within phagocytic cells. The L. pneumophila effector SidK was identified in a screen for proteins that reduce the activity of the proton pumping vacuolar-type ATPases (V-ATPases) when expressed in the yeast Saccharomyces cerevisae. SidK is secreted by L. pneumophila in the early stages of infection and by binding to and inhibiting the V-ATPase, SidK reduces phagosomal acidification and promotes survival of the bacterium inside macrophages. We determined crystal structures of the N-terminal region of SidK at 2.3 Å resolution and used single particle electron cryomicroscopy (cryo-EM) to determine structures of V-ATPase:SidK complexes at ~6.8 Å resolution. SidK is a flexible and elongated protein composed of an α-helical region that interacts with subunit A of the V-ATPase and a second region of unknown function that is flexibly-tethered to the first. SidK binds V-ATPase strongly by interacting via two α-helical bundles at its N terminus with subunit A. In vitro activity assays show that SidK does not inhibit the V-ATPase completely, but reduces its activity by ~40%, consistent with the partial V-ATPase deficiency phenotype its expression causes in yeast. The cryo-EM analysis shows that SidK reduces the flexibility of the A-subunit that is in the ‘open’ conformation. Fluorescence experiments indicate that SidK binding decreases the affinity of V-ATPase for a fluorescent analogue of ATP. Together, these results reveal the structural basis for the fine-tuning of V-ATPase activity by SidK. V-ATPase-driven acidification of lysosomes in phagocytic cells activates enzymes important for killing of phagocytized pathogens. Successful pathogens can subvert host defenses by secreting effectors that target V-ATPases to inhibit lysosomal acidification or lysosomal fusion with other cell compartments. This study reveals the structure of the V-ATPase:SidK complex, an assembly formed from the interaction of host and pathogen proteins involved in the infection of phagocytic white blood cells by Legionella pneumophila. The structure and activity of the V-ATPase is altered upon SidK binding, providing insight into the infection strategy used by L. pneumophila and possibly other intravacuolar pathogens.
Collapse
Affiliation(s)
- Jianhua Zhao
- The Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Ksenia Beyrakhova
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Yao Liu
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Claudia P. Alvarez
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | | | - Li Xu
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Caishuang Xu
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Michal T. Boniecki
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Voula Kanelis
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Zhao-Qing Luo
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Miroslaw Cygler
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- * E-mail: (JLR); (MC)
| | - John L. Rubinstein
- The Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
- * E-mail: (JLR); (MC)
| |
Collapse
|
37
|
Wang C, Zhao T, Li Y, Huang G, White MA, Gao J. Investigation of endosome and lysosome biology by ultra pH-sensitive nanoprobes. Adv Drug Deliv Rev 2017; 113:87-96. [PMID: 27612550 PMCID: PMC5339051 DOI: 10.1016/j.addr.2016.08.014] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 08/29/2016] [Accepted: 08/30/2016] [Indexed: 01/08/2023]
Abstract
Endosomes and lysosomes play a critical role in various aspects of cell physiology such as nutrient sensing, receptor recycling, protein/lipid catabolism, and cell death. In drug delivery, endosomal release of therapeutic payloads from nanocarriers is also important in achieving efficient delivery of drugs to reach their intracellular targets. Recently, we invented a library of ultra pH-sensitive (UPS) nanoprobes with exquisite fluorescence response to subtle pH changes. The UPS nanoprobes also displayed strong pH-specific buffer effect over small molecular bases with broad pH responses (e.g., chloroquine and NH4Cl). Tunable pH transitions from 7.4 to 4.0 of UPS nanoprobes cover the entire physiological pH of endocytic organelles (e.g., early and late endosomes) and lysosomes. These unique physico-chemical properties of UPS nanoprobes allowed a 'detection and perturbation' strategy for the investigation of luminal pH in cell signaling and metabolism, which introduces a nanotechnology-enabled paradigm for the biological studies of endosomes and lysosomes.
Collapse
Affiliation(s)
- Chensu Wang
- Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Tian Zhao
- Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Yang Li
- Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Gang Huang
- Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Michael A White
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Jinming Gao
- Department of Pharmacology, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA.
| |
Collapse
|
38
|
Colombo C, Li M, Watanabe S, Messa P, Edefonti A, Montini G, Moscatelli D, Rastaldi MP, Cellesi F. Polymer Nanoparticle Engineering for Podocyte Repair: From in Vitro Models to New Nanotherapeutics in Kidney Diseases. ACS OMEGA 2017; 2:599-610. [PMID: 30023613 PMCID: PMC6044764 DOI: 10.1021/acsomega.6b00423] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 02/08/2017] [Indexed: 05/21/2023]
Abstract
Specific therapeutic targeting of kidney podocytes, the highly differentiated ramified glomerular cells involved in the onset and/or progression of proteinuric diseases, could become the optimal strategy for preventing chronic kidney disease. With this aim, we developed a library of engineered polymeric nanoparticles (NPs) of tuneable size and surface properties and evaluated their interaction with podocytes. NP cytotoxicity, uptake, and cytoskeletal effects on podocytes were first assessed. On the basis of these data, nanodelivery of dexamethasone loaded into selected biocompatible NPs was successful in repairing damaged podocytes. Finally, a three-dimensional in vitro system of co-culture of endothelial cells and podocytes was exploited as a new tool for mimicking the mechanisms of NP interaction with glomerular cells and the repair of the kidney filtration barrier.
Collapse
Affiliation(s)
- Claudio Colombo
- Dipartimento
di Chimica, Materiali ed Ingegneria Chimica
“G. Natta”. Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy
| | - Min Li
- Fondazione
CEN - European Centre for Nanomedicine, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
- Renal
Research Laboratory, Fondazione IRCCS Ca’
Granda Ospedale Maggiore Policlinico, Via Pace 9, 20122 Milan, Italy
| | - Shojiro Watanabe
- Renal
Research Laboratory, Fondazione IRCCS Ca’
Granda Ospedale Maggiore Policlinico, Via Pace 9, 20122 Milan, Italy
| | - Piergiorgio Messa
- Renal
Research Laboratory, Fondazione IRCCS Ca’
Granda Ospedale Maggiore Policlinico, Via Pace 9, 20122 Milan, Italy
| | - Alberto Edefonti
- Pediatric
Nephrology and Dialysis Unit, Department of Clinical Sciences and
Community Health, University of Milan, Fondazione
IRCCS Ca’ Granda - Ospedale Maggiore Policlinico, Via Commenda, 20122 Milano, Italy
| | - Giovanni Montini
- Pediatric
Nephrology and Dialysis Unit, Department of Clinical Sciences and
Community Health, University of Milan, Fondazione
IRCCS Ca’ Granda - Ospedale Maggiore Policlinico, Via Commenda, 20122 Milano, Italy
| | - Davide Moscatelli
- Dipartimento
di Chimica, Materiali ed Ingegneria Chimica
“G. Natta”. Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy
| | - Maria Pia Rastaldi
- Renal
Research Laboratory, Fondazione IRCCS Ca’
Granda Ospedale Maggiore Policlinico, Via Pace 9, 20122 Milan, Italy
| | - Francesco Cellesi
- Fondazione
CEN - European Centre for Nanomedicine, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
- Renal
Research Laboratory, Fondazione IRCCS Ca’
Granda Ospedale Maggiore Policlinico, Via Pace 9, 20122 Milan, Italy
- Dipartimento
di Chimica, Materiali ed Ingegneria Chimica
“G. Natta”. Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy
- E-mail:
| |
Collapse
|
39
|
Bourdenx M, Daniel J, Genin E, Soria FN, Blanchard-Desce M, Bezard E, Dehay B. Nanoparticles restore lysosomal acidification defects: Implications for Parkinson and other lysosomal-related diseases. Autophagy 2016; 12:472-83. [PMID: 26761717 DOI: 10.1080/15548627.2015.1136769] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Lysosomal impairment causes lysosomal storage disorders (LSD) and is involved in pathogenesis of neurodegenerative diseases, notably Parkinson disease (PD). Strategies enhancing or restoring lysosomal-mediated degradation thus appear as tantalizing disease-modifying therapeutics. Here we demonstrate that poly(DL-lactide-co-glycolide) (PLGA) acidic nanoparticles (aNP) restore impaired lysosomal function in a series of toxin and genetic cellular models of PD, i.e. ATP13A2-mutant or depleted cells or glucocerebrosidase (GBA)-mutant cells, as well as in a genetic model of lysosomal-related myopathy. We show that PLGA-aNP are transported to the lysosome within 24 h, lower lysosomal pH and rescue chloroquine (CQ)-induced toxicity. Re-acidification of defective lysosomes following PLGA-aNP treatment restores lysosomal function in different pathological contexts. Finally, our results show that PLGA-aNP may be detected after intracerebral injection in neurons and attenuate PD-related neurodegeneration in vivo by mechanisms involving a rescue of compromised lysosomes.
Collapse
Affiliation(s)
- Mathieu Bourdenx
- a University de Bordeaux, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France.,b CNRS, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France
| | - Jonathan Daniel
- c University de Bordeaux, Institut des Sciences Moléculaires , UMR 5255, Talence , France
| | - Emilie Genin
- c University de Bordeaux, Institut des Sciences Moléculaires , UMR 5255, Talence , France
| | - Federico N Soria
- a University de Bordeaux, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France.,b CNRS, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France
| | | | - Erwan Bezard
- a University de Bordeaux, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France.,b CNRS, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France
| | - Benjamin Dehay
- a University de Bordeaux, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France.,b CNRS, Institut des Maladies Neurodégénératives , UMR 5293, Bordeaux , France
| |
Collapse
|
40
|
Villarroya-Beltri C, Baixauli F, Mittelbrunn M, Fernández-Delgado I, Torralba D, Moreno-Gonzalo O, Baldanta S, Enrich C, Guerra S, Sánchez-Madrid F. ISGylation controls exosome secretion by promoting lysosomal degradation of MVB proteins. Nat Commun 2016; 7:13588. [PMID: 27882925 PMCID: PMC5123068 DOI: 10.1038/ncomms13588] [Citation(s) in RCA: 326] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 10/18/2016] [Indexed: 12/30/2022] Open
Abstract
Exosomes are vesicles secreted to the extracellular environment through fusion with the plasma membrane of specific endosomes called multivesicular bodies (MVB) and mediate cell-to-cell communication in many biological processes. Posttranslational modifications are involved in the sorting of specific proteins into exosomes. Here we identify ISGylation as a ubiquitin-like modification that controls exosome release. ISGylation induction decreases MVB numbers and impairs exosome secretion. Using ISG15-knockout mice and mice expressing the enzymatically inactive form of the de-ISGylase USP18, we demonstrate in vitro and in vivo that ISG15 conjugation regulates exosome secretion. ISG15 conjugation triggers MVB co-localization with lysosomes and promotes the aggregation and degradation of MVB proteins. Accordingly, inhibition of lysosomal function or autophagy restores exosome secretion. Specifically, ISGylation of the MVB protein TSG101 induces its aggregation and degradation, being sufficient to impair exosome secretion. These results identify ISGylation as a novel ubiquitin-like modifier in the control of exosome production. Multivesicular bodies (MVB) are endosomal compartments that can either fuse with the plasma membrane for the secretion of exosomes, or fuse with the lysosome and be degraded along with their contents. Here, the authors show that ISGylation of the MVB protein TSG101 impairs exosome secretion and acts as a regulator of MVB fate.
Collapse
Affiliation(s)
- Carolina Villarroya-Beltri
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain.,Immunology Service, Hospital de la Princesa, Instituto Investigación Sanitaria Princesa, Universidad Autónoma de Madrid, 28006 Madrid, Spain
| | - Francesc Baixauli
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain.,Immunology Service, Hospital de la Princesa, Instituto Investigación Sanitaria Princesa, Universidad Autónoma de Madrid, 28006 Madrid, Spain
| | - María Mittelbrunn
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain
| | - Irene Fernández-Delgado
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain.,Immunology Service, Hospital de la Princesa, Instituto Investigación Sanitaria Princesa, Universidad Autónoma de Madrid, 28006 Madrid, Spain
| | - Daniel Torralba
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain.,Immunology Service, Hospital de la Princesa, Instituto Investigación Sanitaria Princesa, Universidad Autónoma de Madrid, 28006 Madrid, Spain
| | - Olga Moreno-Gonzalo
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain.,Immunology Service, Hospital de la Princesa, Instituto Investigación Sanitaria Princesa, Universidad Autónoma de Madrid, 28006 Madrid, Spain
| | - Sara Baldanta
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, 28029 Madrid, Spain
| | - Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Susana Guerra
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma de Madrid, 28029 Madrid, Spain
| | - Francisco Sánchez-Madrid
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain.,Immunology Service, Hospital de la Princesa, Instituto Investigación Sanitaria Princesa, Universidad Autónoma de Madrid, 28006 Madrid, Spain
| |
Collapse
|
41
|
Ilie A, Gao AYL, Reid J, Boucher A, McEwan C, Barrière H, Lukacs GL, McKinney RA, Orlowski J. A Christianson syndrome-linked deletion mutation (∆(287)ES(288)) in SLC9A6 disrupts recycling endosomal function and elicits neurodegeneration and cell death. Mol Neurodegener 2016; 11:63. [PMID: 27590723 PMCID: PMC5010692 DOI: 10.1186/s13024-016-0129-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 08/27/2016] [Indexed: 01/19/2023] Open
Abstract
Background Christianson Syndrome, a recently identified X-linked neurodevelopmental disorder, is caused by mutations in the human gene SLC9A6 encoding the recycling endosomal alkali cation/proton exchanger NHE6. The patients have pronounced limitations in cognitive ability, motor skills and adaptive behaviour. However, the mechanistic basis for this disorder is poorly understood as few of the more than 20 mutations identified thus far have been studied in detail. Methods Here, we examined the molecular and cellular consequences of a 6 base-pair deletion of amino acids Glu287 and Ser288 (∆ES) in the predicted seventh transmembrane helix of human NHE6 expressed in established cell lines (CHO/AP-1, HeLa and neuroblastoma SH-SY5Y) and primary cultures of mouse hippocampal neurons by measuring levels of protein expression, stability, membrane trafficking, endosomal function and cell viability. Results In the cell lines, immunoblot analyses showed that the nascent mutant protein was properly synthesized and assembled as a homodimer, but its oligosaccharide maturation and half-life were markedly reduced compared to wild-type (WT) and correlated with enhanced ubiquitination leading to both proteasomal and lysosomal degradation. Despite this instability, a measurable fraction of the transporter was correctly sorted to the plasma membrane. However, the rates of clathrin-mediated endocytosis of the ∆ES mutant as well as uptake of companion vesicular cargo, such as the ligand-bound transferrin receptor, were significantly reduced and correlated with excessive endosomal acidification. Notably, ectopic expression of ∆ES but not WT induced apoptosis when examined in AP-1 cells. Similarly, in transfected primary cultures of mouse hippocampal neurons, membrane trafficking of the ∆ES mutant was impaired and elicited marked reductions in total dendritic length, area and arborization, and triggered apoptotic cell death. Conclusions These results suggest that loss-of-function mutations in NHE6 disrupt recycling endosomal function and trafficking of cargo which ultimately leads to neuronal degeneration and cell death in Christianson Syndrome. Electronic supplementary material The online version of this article (doi:10.1186/s13024-016-0129-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Alina Ilie
- Department of Physiology, McGill University, Bellini Life Sciences Bldg., Rm, 166, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada
| | - Andy Y L Gao
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Canada
| | - Jonathan Reid
- Department of Physiology, McGill University, Bellini Life Sciences Bldg., Rm, 166, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada
| | - Annie Boucher
- Department of Physiology, McGill University, Bellini Life Sciences Bldg., Rm, 166, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada
| | - Cassandra McEwan
- Department of Physiology, McGill University, Bellini Life Sciences Bldg., Rm, 166, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada
| | - Hervé Barrière
- Department of Physiology, McGill University, Bellini Life Sciences Bldg., Rm, 166, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada
| | - Gergely L Lukacs
- Department of Physiology, McGill University, Bellini Life Sciences Bldg., Rm, 166, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada
| | - R Anne McKinney
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Canada
| | - John Orlowski
- Department of Physiology, McGill University, Bellini Life Sciences Bldg., Rm, 166, 3649 Promenade Sir-William-Osler, Montreal, QC, H3G 0B1, Canada.
| |
Collapse
|
42
|
Meo-Evoli N, Almacellas E, Massucci FA, Gentilella A, Ambrosio S, Kozma SC, Thomas G, Tauler A. V-ATPase: a master effector of E2F1-mediated lysosomal trafficking, mTORC1 activation and autophagy. Oncotarget 2016; 6:28057-70. [PMID: 26356814 PMCID: PMC4695044 DOI: 10.18632/oncotarget.4812] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/30/2015] [Indexed: 11/26/2022] Open
Abstract
In addition to being a master regulator of cell cycle progression, E2F1 regulates other associated biological processes, including growth and malignancy. Here, we uncover a regulatory network linking E2F1 to lysosomal trafficking and mTORC1 signaling that involves v-ATPase regulation. By immunofluorescence and time-lapse microscopy we found that E2F1 induces the movement of lysosomes to the cell periphery, and that this process is essential for E2F1-induced mTORC1 activation and repression of autophagy. Gain- and loss-of-function experiments reveal that E2F1 regulates v-ATPase activity and inhibition of v-ATPase activity repressed E2F1-induced lysosomal trafficking and mTORC1 activation. Immunoprecipitation experiments demonstrate that E2F1 induces the recruitment of v-ATPase to lysosomal RagB GTPase, suggesting that E2F1 regulates v-ATPase activity by enhancing the association of V0 and V1 v-ATPase complex. Analysis of v-ATPase subunit expression identified B subunit of V0 complex, ATP6V0B, as a transcriptional target of E2F1. Importantly, ATP6V0B ectopic-expression increased v-ATPase and mTORC1 activity, consistent with ATP6V0B being responsible for mediating the effects of E2F1 on both responses. Our findings on lysosomal trafficking, mTORC1 activation and autophagy suppression suggest that pharmacological intervention at the level of v-ATPase may be an efficacious avenue for the treatment of metastatic processes in tumors overexpressing E2F1.
Collapse
Affiliation(s)
- Nathalie Meo-Evoli
- Departament de Bioquímica i Biologia Molecular, Facultat de Farmàcia, Universitat de Barcelona, 08028 Barcelona, Catalunya, Spain.,Laboratory of Cancer Metabolism, IDIBELL, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain
| | - Eugènia Almacellas
- Departament de Bioquímica i Biologia Molecular, Facultat de Farmàcia, Universitat de Barcelona, 08028 Barcelona, Catalunya, Spain.,Laboratory of Cancer Metabolism, IDIBELL, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain
| | | | - Antonio Gentilella
- Laboratory of Cancer Metabolism, IDIBELL, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain
| | - Santiago Ambrosio
- Unitat de Bioquímica, Dep. Ciències Fisiològiques II, Facultat de Medicina, Campus Universitari de Bellvitge - IDIBELL, Universitat de Barcelona, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain
| | - Sara C Kozma
- Laboratory of Cancer Metabolism, IDIBELL, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain.,Laboratory of Cancer Metabolism, Institut Català d'Oncologia, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain.,Division of Hematology and Oncology, Department of Internal Medicine, College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267, USA
| | - George Thomas
- Laboratory of Cancer Metabolism, IDIBELL, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain.,Unitat de Bioquímica, Dep. Ciències Fisiològiques II, Facultat de Medicina, Campus Universitari de Bellvitge - IDIBELL, Universitat de Barcelona, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain.,Laboratory of Cancer Metabolism, Institut Català d'Oncologia, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain.,Division of Hematology and Oncology, Department of Internal Medicine, College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267, USA
| | - Albert Tauler
- Departament de Bioquímica i Biologia Molecular, Facultat de Farmàcia, Universitat de Barcelona, 08028 Barcelona, Catalunya, Spain.,Laboratory of Cancer Metabolism, IDIBELL, Hospital Duran i Reynals, 08908 L'Hospitalet de Llobregat, Barcelona, Catalunya, Spain
| |
Collapse
|
43
|
Johnson DE, Ostrowski P, Jaumouillé V, Grinstein S. The position of lysosomes within the cell determines their luminal pH. J Cell Biol 2016; 212:677-92. [PMID: 26975849 PMCID: PMC4792074 DOI: 10.1083/jcb.201507112] [Citation(s) in RCA: 383] [Impact Index Per Article: 47.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Analysis of luminal lysosomal pH in combination with heterologous expression of lysosomal-associated proteins indicates that peripheral lysosomes are more alkaline than juxtanuclear ones and that depletion of Rab7 and its effector, RILP, are associated with and can account for the reduced acidification. We examined the luminal pH of individual lysosomes using quantitative ratiometric fluorescence microscopy and report an unappreciated heterogeneity: peripheral lysosomes are less acidic than juxtanuclear ones despite their comparable buffering capacity. An increased passive (leak) permeability to protons, together with reduced vacuolar H+–adenosine triphosphatase (V-ATPase) activity, accounts for the reduced acidifying ability of peripheral lysosomes. The altered composition of peripheral lysosomes is due, at least in part, to more limited access to material exported by the biosynthetic pathway. The balance between Rab7 and Arl8b determines the subcellular localization of lysosomes; more peripheral lysosomes have reduced Rab7 density. This in turn results in decreased recruitment of Rab-interacting lysosomal protein (RILP), an effector that regulates the recruitment and stability of the V1G1 component of the lysosomal V-ATPase. Deliberate margination of lysosomes is associated with reduced acidification and impaired proteolytic activity. The heterogeneity in lysosomal pH may be an indication of a broader functional versatility.
Collapse
Affiliation(s)
- Danielle E Johnson
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Philip Ostrowski
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Valentin Jaumouillé
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Sergio Grinstein
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| |
Collapse
|
44
|
Nishikawa H, Miyazaki T, Nakayama H, Minematsu A, Yamauchi S, Yamashita K, Takazono T, Shimamura S, Nakamura S, Izumikawa K, Yanagihara K, Kohno S, Mukae H. Roles of vacuolar H+-ATPase in the oxidative stress response of Candida glabrata. FEMS Yeast Res 2016; 16:fow054. [PMID: 27370212 DOI: 10.1093/femsyr/fow054] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2016] [Indexed: 11/13/2022] Open
Abstract
Vacuolar H(+)-ATPase (V-ATPase) is responsible for the acidification of eukaryotic intracellular compartments and plays an important role in oxidative stress response (OSR), but its molecular bases are largely unknown. Here, we investigated how V-ATPase is involved in the OSR by using a strain lacking VPH2, which encodes an assembly factor of V-ATPase, in the pathogenic fungus Candida glabrata The loss of Vph2 resulted in increased H2O2 sensitivity and intracellular reactive oxygen species (ROS) level independently of mitochondrial functions. The Δvph2 mutant also displayed growth defects under alkaline conditions accompanied by the accumulation of intracellular ROS and these phenotypes were recovered in the presence of the ROS scavenger N-acetyl-l-cysteine. Both expression and activity levels of mitochondrial manganese superoxide dismutase (Sod2) and catalase (Cta1) were decreased in the Δvph2 mutant. Phenotypic analyses of strains lacking and overexpressing these genes revealed that Sod2 and Cta1 play a predominant role in endogenous and exogenous OSR, respectively. Furthermore, supplementation of copper and iron restored the expression of SOD2 specifically in the Δvph2 mutant, suggesting that the homeostasis of intracellular cupper and iron levels maintained by V-ATPase was important for the Sod2-mediated OSR. This report demonstrates novel roles of V-ATPase in the OSR in C. glabrata.
Collapse
Affiliation(s)
- Hiroshi Nishikawa
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan Department of Respiratory Medicine, Unit of Translational Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Taiga Miyazaki
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan Department of Respiratory Medicine, Unit of Translational Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan Division of Infectious Diseases, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Hironobu Nakayama
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Sciences, Suzuka, Mie 513-8670, Japan
| | - Asuka Minematsu
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan
| | - Shunsuke Yamauchi
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Kohei Yamashita
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan
| | - Takahiro Takazono
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan Division of Infectious Diseases, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Shintaro Shimamura
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan
| | - Shigeki Nakamura
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan
| | - Koichi Izumikawa
- Division of Infectious Diseases, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Katsunori Yanagihara
- Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Shigeru Kohno
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan
| | - Hiroshi Mukae
- Second Department of Internal Medicine, Nagasaki University, Nagasaki 852-8501, Japan Department of Respiratory Medicine, Unit of Translational Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| |
Collapse
|
45
|
Xu Y, Wei MT, Ou-Yang HD, Walker SG, Wang HZ, Gordon CR, Guterman S, Zawacki E, Applebaum E, Brink PR, Rafailovich M, Mironava T. Exposure to TiO2 nanoparticles increases Staphylococcus aureus infection of HeLa cells. J Nanobiotechnology 2016; 14:34. [PMID: 27102228 PMCID: PMC4840899 DOI: 10.1186/s12951-016-0184-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 04/10/2016] [Indexed: 01/02/2023] Open
Abstract
Background Titanium dioxide (TiO2) is one of the most common nanoparticles found in industry ranging from food additives to energy generation. Approximately four million tons of TiO2 particles are produced worldwide each year with approximately 3000 tons being produced in nanoparticulate form, hence exposure to these particles is almost certain. Results Even though TiO2 is also used as an anti-bacterial agent in combination with UV, we have found that, in the absence of UV, exposure of HeLa cells to TiO2 nanoparticles significantly increased their risk of bacterial invasion. HeLa cells cultured with 0.1 mg/ml rutile and anatase TiO2 nanoparticles for 24 h prior to exposure to bacteria had 350 and 250 % respectively more bacteria per cell. The increase was attributed to bacterial polysaccharides absorption on TiO2 NPs, increased extracellular LDH, and changes in the mechanical response of the cell membrane. On the other hand, macrophages exposed to TiO2 particles ingested 40 % fewer bacteria, further increasing the risk of infection. Conclusions In combination, these two factors raise serious concerns regarding the impact of exposure to TiO2 nanoparticles on the ability of organisms to resist bacterial infection. Electronic supplementary material The online version of this article (doi:10.1186/s12951-016-0184-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Yan Xu
- Department of Materials Science and Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Ming-Tzo Wei
- Department of Bioengineering, Lehigh University, Bethlehem, PA, USA
| | - H Daniel Ou-Yang
- Department of Bioengineering, Lehigh University, Bethlehem, PA, USA
| | - Stephen G Walker
- Department of Oral Biology and Pathology, School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Hong Zhan Wang
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Chris R Gordon
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | | | - Emma Zawacki
- University of California at Los Angeles, Los Angeles, CA, USA
| | | | - Peter R Brink
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Miriam Rafailovich
- Department of Materials Science and Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Tatsiana Mironava
- Department of Materials Science and Engineering, Stony Brook University, Stony Brook, NY, USA.
| |
Collapse
|
46
|
Smith GA, Howell GJ, Phillips C, Muench SP, Ponnambalam S, Harrison MA. Extracellular and Luminal pH Regulation by Vacuolar H+-ATPase Isoform Expression and Targeting to the Plasma Membrane and Endosomes. J Biol Chem 2016; 291:8500-15. [PMID: 26912656 PMCID: PMC4861423 DOI: 10.1074/jbc.m116.723395] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Indexed: 01/02/2023] Open
Abstract
Plasma membrane vacuolar H+-ATPase (V-ATPase) activity of tumor cells is a major factor in control of cytoplasmic and extracellular pH and metastatic potential, but the isoforms involved and the factors governing plasma membrane recruitment remain uncertain. Here, we examined expression, distribution, and activity of V-ATPase isoforms in invasive prostate adenocarcinoma (PC-3) cells. Isoforms 1 and 3 were the most highly expressed forms of membrane subunit a, with a1 and a3 the dominant plasma membrane isoforms. Correlation between plasma membrane V-ATPase activity and invasiveness was limited, but RNAi knockdown of either a isoform did slow cell proliferation and inhibit invasion in vitro. Isoform a1 was recruited to the cell surface from the early endosome-recycling complex pathway, its knockdown arresting transferrin receptor recycling. Isoform a3 was associated with the late endosomal/lysosomal compartment. Both a isoforms associated with accessory protein Ac45, knockdown of which stalled transit of a1 and transferrin-transferrin receptor, decreased proton efflux, and reduced cell growth and invasiveness; this latter effect was at least partly due to decreased delivery of the membrane-bound matrix metalloproteinase MMP-14 to the plasma membrane. These data indicate that in prostatic carcinoma cells, a1 and a3 isoform populations predominate in different compartments where they maintain different luminal pH. Ac45 plays a central role in navigating the V-ATPase to the plasma membrane, and hence it is an important factor in expression of the invasive phenotype.
Collapse
Affiliation(s)
- Gina A Smith
- From the Endothelial Cell Biology Unit, School of Molecular and Cellular Biology and
| | - Gareth J Howell
- From the Endothelial Cell Biology Unit, School of Molecular and Cellular Biology and
| | - Clair Phillips
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Stephen P Muench
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | | | - Michael A Harrison
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| |
Collapse
|
47
|
Ghosh D, Pinto S, Danglot L, Vandewauw I, Segal A, Van Ranst N, Benoit M, Janssens A, Vennekens R, Vanden Berghe P, Galli T, Vriens J, Voets T. VAMP7 regulates constitutive membrane incorporation of the cold-activated channel TRPM8. Nat Commun 2016; 7:10489. [PMID: 26843440 PMCID: PMC4742910 DOI: 10.1038/ncomms10489] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 12/18/2015] [Indexed: 02/06/2023] Open
Abstract
The cation channel TRPM8 plays a central role in the somatosensory system, as a key sensor of innocuously cold temperatures and cooling agents. Although increased functional expression of TRPM8 has been implicated in various forms of pathological cold hypersensitivity, little is known about the cellular and molecular mechanisms that determine TRPM8 abundance at the plasma membrane. Here we demonstrate constitutive transport of TRPM8 towards the plasma membrane in atypical, non-acidic transport vesicles that contain lysosomal-associated membrane protein 1 (LAMP1), and provide evidence that vesicle-associated membrane protein 7 (VAMP7) mediates fusion of these vesicles with the plasma membrane. In line herewith, VAMP7-deficient mice exhibit reduced functional expression of TRPM8 in sensory neurons and concomitant deficits in cold avoidance and icilin-induced cold hypersensitivity. Our results uncover a cellular pathway that controls functional plasma membrane incorporation of a temperature-sensitive TRP channel, and thus regulates thermosensitivity in vivo.
Collapse
Affiliation(s)
- Debapriya Ghosh
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Silvia Pinto
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Lydia Danglot
- Institut Jacques Monod, CNRS UMR 7592, University of Paris Diderot, F-75013 Paris, France
- INSERM ERL U950, Membrane Traffic in Health & disease Group, F-75013 Paris, France
| | - Ine Vandewauw
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Andrei Segal
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Nele Van Ranst
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Melissa Benoit
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Annelies Janssens
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Rudi Vennekens
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| | - Pieter Vanden Berghe
- Laboratory for Enteric NeuroScience, Department of Clinical and Experimental Medicine, University of Leuven, B-3000 Leuven, Belgium
- Translational Research Centre for Gastrointestinal Disorders, KU Leuven, Herestraat 49 box 701, B-3000 Leuven, Belgium
| | - Thierry Galli
- Institut Jacques Monod, CNRS UMR 7592, University of Paris Diderot, F-75013 Paris, France
- INSERM ERL U950, Membrane Traffic in Health & disease Group, F-75013 Paris, France
| | - Joris Vriens
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
- Laboratory of Experimental Gynaecology, Department of Development and Regeneration, University of Leuven, Herestraat 49 box 611, B-3000 Leuven, Belgium
| | - Thomas Voets
- Laboratory of Ion Channel Research and TRP Channel Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 box 802, B-3000 Leuven, Belgium
| |
Collapse
|
48
|
Widdison WC, Ponte JF, Coccia JA, Lanieri L, Setiady Y, Dong L, Skaletskaya A, Hong EE, Wu R, Qiu Q, Singh R, Salomon P, Fishkin N, Harris L, Maloney EK, Kovtun Y, Veale K, Wilhelm SD, Audette CA, Costoplus JA, Chari RVJ. Development of Anilino-Maytansinoid ADCs that Efficiently Release Cytotoxic Metabolites in Cancer Cells and Induce High Levels of Bystander Killing. Bioconjug Chem 2015; 26:2261-78. [DOI: 10.1021/acs.bioconjchem.5b00430] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Jose F. Ponte
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | | | - Leanne Lanieri
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Yulius Setiady
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Ling Dong
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | | | - E. Erica Hong
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Rui Wu
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Qifeng Qiu
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Rajeeva Singh
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Paulin Salomon
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Nathan Fishkin
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Luke Harris
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | | | - Yelena Kovtun
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | - Karen Veale
- ImmunoGen Inc., Waltham, Massachusetts 02451, United States
| | | | | | | | | |
Collapse
|
49
|
Tsuruta Y, Shibutani ST, Watanabe R, Iwata H. The requirement of environmental acidification for Ibaraki virus infection to host cells. J Vet Med Sci 2015; 78:153-6. [PMID: 26321298 PMCID: PMC4751137 DOI: 10.1292/jvms.15-0222] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The effect of environmental acidification on Ibaraki virus (IBAV) infection was tested
using endosomal inhibitory chemicals and low pH treatment. Treatment of target cells with
endosomal inhibitors significantly decreased the progeny virus production. IBAV outer
capsid proteins, VP5 and VP2, were removed from virion when purified IBAV was exposed to
low pH environment. Further experiment showed that the exposure to low pH buffer
facilitated IBAV infection when the cellular endosomal pathway was impaired by bafilomycin
A1. Results obtained in this study suggest that acidic environment is essential to
initiate IBAV infection.
Collapse
Affiliation(s)
- Yuya Tsuruta
- Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-0841, Japan
| | | | | | | |
Collapse
|
50
|
Thakur V, Asad M, Jain S, Hossain ME, Gupta A, Kaur I, Rathore S, Ali S, Khan NJ, Mohmmed A. Eps15 homology domain containing protein of Plasmodium falciparum (PfEHD) associates with endocytosis and vesicular trafficking towards neutral lipid storage site. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2856-69. [PMID: 26284889 DOI: 10.1016/j.bbamcr.2015.08.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 07/19/2015] [Accepted: 08/07/2015] [Indexed: 01/08/2023]
Abstract
The human malaria parasite, Plasmodium falciparum, takes up numerous host cytosolic components and exogenous nutrients through endocytosis during the intra-erythrocytic stages. Eps15 homology domain-containing proteins (EHDs) are conserved NTPases, which are implicated in membrane remodeling and regulation of specific endocytic transport steps in eukaryotic cells. In the present study, we have characterized the dynamin-like C-terminal Eps15 homology domain containing protein of P. falciparum (PfEHD). Using a GFP-targeting approach, we studied localization and trafficking of PfEHD in the parasite. The PfEHD-GFP fusion protein was found to be a membrane bound protein that associates with vesicular network in the parasite. Time-lapse microscopy studies showed that these vesicles originate at parasite plasma membrane, migrate through the parasite cytosol and culminate into a large multi-vesicular like structure near the food-vacuole. Co-staining of food vacuole membrane showed that the multi-vesicular structure is juxtaposed but outside the food vacuole. Labeling of parasites with neutral lipid specific dye, Nile Red, showed that this large structure is neutral lipid storage site in the parasites. Proteomic analysis identified endocytosis modulators as PfEHD associated proteins in the parasites. Treatment of parasites with endocytosis inhibitors obstructed the development of PfEHD-labeled vesicles and blocked their targeting to the lipid storage site. Overall, our data suggests that the PfEHD is involved in endocytosis and plays a role in the generation of endocytic vesicles at the parasite plasma membrane, that are subsequently targeted to the neutral lipid generation/storage site localized near the food vacuole.
Collapse
Affiliation(s)
- Vandana Thakur
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110 067, India
| | - Mohd Asad
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110 067, India; Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110 025, India
| | - Shaifali Jain
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110 067, India
| | - Mohammad E Hossain
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110 067, India
| | - Akanksha Gupta
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110 067, India
| | - Inderjeet Kaur
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110 067, India
| | - Sumit Rathore
- Department of Biotechnology, All India Institute of Medical Sciences, New Delhi 110 029, India
| | - Shakir Ali
- Department of Biochemistry, Faculty of Science, Jamia Hamdard, New Delhi 110062, India
| | - Nida J Khan
- Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110 025, India
| | - Asif Mohmmed
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110 067, India.
| |
Collapse
|