1
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Jones DJ, Soundararajan D, Taylor NK, Aimiuwu OV, Mathkar P, Shore A, Teoh JJ, Wang W, Sands TT, Weston MC, Harper SQ, Frankel WN. Effective knockdown-replace gene therapy in a novel mouse model of DNM1 developmental and epileptic encephalopathy. Mol Ther 2024; 32:3318-3330. [PMID: 39127888 DOI: 10.1016/j.ymthe.2024.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 07/12/2024] [Accepted: 08/06/2024] [Indexed: 08/12/2024] Open
Abstract
Effective gene therapy for gain-of-function or dominant-negative disease mutations may require eliminating expression of the mutant copy together with wild-type replacement. We evaluated such a knockdown-replace strategy in a mouse model of DNM1 disease, a debilitating and intractable neurodevelopmental epilepsy. To challenge the approach robustly, we expressed a patient-based variant in GABAergic neurons-which resulted in growth delay and lethal seizures evident by postnatal week three-and delivered to newborn pups an AAV9-based vector encoding a ubiquitously expressed, Dnm1-specific interfering RNA (RNAi) bivalently in tail-to-tail configuration with a neuron-specific, RNAi-resistant, codon-optimized Dnm1 cDNA. Pups receiving RNAi or cDNA alone fared no better than untreated pups, whereas the vast majority of mutants receiving modest doses survived with almost full growth recovery. Synaptic recordings of cortical neurons derived from treated pups revealed that significant alterations in transmission from inhibitory to excitatory neurons were rectified by bivalent vector application. To examine the mutant transcriptome and impact of treatment, we used RNA sequencing and functional annotation clustering. Mutants displayed abnormal expression of more than 1,000 genes in highly significant and relevant functional clusters, clusters that were abrogated by treatment. Together these results suggest knockdown-replace as a potentially effective strategy for treating DNM1 and related genetic neurodevelopmental disease.
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Affiliation(s)
- Devin J Jones
- Department of Genetics and Development and Department of Neurology, Center for Translational Research in Neurodevelopmental Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Divya Soundararajan
- Department of Genetics and Development and Department of Neurology, Center for Translational Research in Neurodevelopmental Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Noah K Taylor
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Osasumwen V Aimiuwu
- Department of Genetics and Development and Department of Neurology, Center for Translational Research in Neurodevelopmental Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Pranav Mathkar
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, USA
| | - Amy Shore
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, USA
| | - Jia Jie Teoh
- Department of Genetics and Development and Department of Neurology, Center for Translational Research in Neurodevelopmental Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Wanqi Wang
- Department of Genetics and Development and Department of Neurology, Center for Translational Research in Neurodevelopmental Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Tristan T Sands
- Department of Genetics and Development and Department of Neurology, Center for Translational Research in Neurodevelopmental Disease, Columbia University Irving Medical Center, New York, NY, USA
| | - Matthew C Weston
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, USA
| | - Scott Q Harper
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Wayne N Frankel
- Department of Genetics and Development and Department of Neurology, Center for Translational Research in Neurodevelopmental Disease, Columbia University Irving Medical Center, New York, NY, USA.
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2
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Zhang H, Chang M, Chen D, Yang J, Zhang Y, Sun J, Yao X, Sun H, Gu X, Li M, Shen Y, Dai B. Congenital myopathies: pathophysiological mechanisms and promising therapies. J Transl Med 2024; 22:815. [PMID: 39223631 PMCID: PMC11370226 DOI: 10.1186/s12967-024-05626-5] [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: 01/03/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024] Open
Abstract
Congenital myopathies (CMs) are a kind of non-progressive or slow-progressive muscle diseases caused by genetic mutations, which are currently defined and categorized mainly according to their clinicopathological features. CMs exhibit pleiotropy and genetic heterogeneity. Currently, supportive treatment and pharmacological remission are the mainstay of treatment, with no cure available. Some adeno-associated viruses show promising prospects in the treatment of MTM1 and BIN1-associated myopathies; however, such gene-level therapeutic interventions target only specific mutation types and are not generalizable. Thus, it is particularly crucial to identify the specific causative genes. Here, we outline the pathogenic mechanisms based on the classification of causative genes: excitation-contraction coupling and triadic assembly (RYR1, MTM1, DNM2, BIN1), actin-myosin interaction and production of myofibril forces (NEB, ACTA1, TNNT1, TPM2, TPM3), as well as other biological processes. Furthermore, we provide a comprehensive overview of recent therapeutic advancements and potential treatment modalities of CMs. Despite ongoing research endeavors, targeted strategies and collaboration are imperative to address diagnostic uncertainties and explore potential treatments.
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Affiliation(s)
- Han Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Mengyuan Chang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Daiyue Chen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Jiawen Yang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Yijie Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Jiacheng Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Xinlei Yao
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Hualin Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Xiaosong Gu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China
| | - Meiyuan Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China.
| | - Yuntian Shen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical College, Nantong University, Nantong, Jiangsu Province, 226001, P. R. China.
| | - Bin Dai
- Department of Orthopedics, Binhai County People's Hospital, Binhai, Jiangsu Province, 224500, P. R. China.
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3
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Zuriegat Q, Abubakar YS, Wang Z, Chen M, Zhang J. Emerging Roles of Exocyst Complex in Fungi: A Review. J Fungi (Basel) 2024; 10:614. [PMID: 39330374 PMCID: PMC11433146 DOI: 10.3390/jof10090614] [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: 07/25/2024] [Revised: 08/19/2024] [Accepted: 08/21/2024] [Indexed: 09/28/2024] Open
Abstract
The exocyst complex, an evolutionarily conserved octameric protein assembly, plays a central role in the targeted binding and fusion of vesicles at the plasma membrane. In fungal cells, this transport system is essential for polarized growth, morphogenesis, cell wall maintenance and virulence. Recent advances have greatly improved our understanding of the role and regulation of the exocyst complex in fungi. This review synthesizes these developments and focuses on the intricate interplay between the exocyst complex, specific fungal cargos and regulatory proteins. Insights into thestructure of the exocyst and its functional dynamics have revealed new dimensions of its architecture and its interactions with the cellular environment. Furthermore, the regulation of exocyst activity involves complex signaling pathways and interactions with cytoskeletal elements that are crucial for its role in vesicle trafficking. By exploring these emerging themes, this review provides a comprehensive overview of the multifaceted functions of the exocyst complex in fungal biology. Understanding these mechanisms offers potential avenues for novel therapeutic strategies against fungal pathogens and insights into the general principles of vesicle trafficking in eukaryotic cells. The review therefore highlights the importance of the exocyst complex in maintaining cellular functions and its broader implications in fungal pathogenicity and cell biology.
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Affiliation(s)
- Qussai Zuriegat
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Q.Z.); (Y.S.A.); (Z.W.)
| | - Yakubu Saddeeq Abubakar
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Q.Z.); (Y.S.A.); (Z.W.)
| | - Zonghua Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Q.Z.); (Y.S.A.); (Z.W.)
- Fujian Key Laboratory on Conservation and Sustainable Utilization of Marine Biodiversity, College of Materials and Chemical Engineering, Minjiang University, Fuzhou 350108, China
| | - Meilian Chen
- Fujian Key Laboratory on Conservation and Sustainable Utilization of Marine Biodiversity, College of Materials and Chemical Engineering, Minjiang University, Fuzhou 350108, China
| | - Jun Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Q.Z.); (Y.S.A.); (Z.W.)
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4
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Alimohamadi H, Luo EWC, Yang R, Gupta S, Nolden KA, Mandal T, Blake Hill R, Wong GCL. Dynamins combine mechano-constriction and membrane remodeling to enable two-step mitochondrial fission via a 'snap-through' instability. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.19.608723. [PMID: 39229060 PMCID: PMC11370335 DOI: 10.1101/2024.08.19.608723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
Mitochondrial fission is controlled by dynamin proteins, the dysregulation of which is correlated with diverse diseases. Fission dynamins are GTP hydrolysis-driven mechanoenzymes that self-oligomerize into helical structures that constrict membrane to achieve fission, but details are not well understood. However, dynamins can also remodel membranes by inducing negative Gaussian curvature, the type of curvature required for completion of fission. Here, we examine how these drastically different mechanisms synergistically exert their influences on a membrane, via a mechanical model calibrated with small-angle X-ray scattering structural data. We find that free dynamin can trigger a "snap-through instability" that enforces a shape transition from an oligomer-confined cylindrical membrane to a drastically narrower catenoid-shaped neck within the spontaneous hemi-fission regime, in a manner that depends critically on the length of the confined tube. These results indicate how the combination of dynamin assembly, and paradoxically disassembly, can lead to diverse pathways to scission.
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Affiliation(s)
- Haleh Alimohamadi
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Elizabeth Wei-Chia Luo
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Rena Yang
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Shivam Gupta
- Department of Physics, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Kelsey A Nolden
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Taraknath Mandal
- Department of Physics, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - R Blake Hill
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, CO, 80045, USA
| | - Gerard C L Wong
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
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5
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Ghani M, Szabó B, Alkhatibe M, Amsalu H, Zohar P, Janka EA, Mótyán JA, Tar K. Serine 39 in the GTP-binding domain of Drp1 is involved in shaping mitochondrial morphology. FEBS Open Bio 2024; 14:1147-1165. [PMID: 38760979 PMCID: PMC11216946 DOI: 10.1002/2211-5463.13820] [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: 01/09/2024] [Revised: 04/18/2024] [Accepted: 05/08/2024] [Indexed: 05/20/2024] Open
Abstract
Continuous fusion and fission are critical for mitochondrial health. In this study, we further characterize the role played by dynamin-related protein 1 (Drp1) in mitochondrial fission. We show that a single amino acid change in Drp1 at position 39 from serine to alanine (S39A) within the GTP-binding (GTPase) domain results in a fused mitochondrial network in human SH-SY5Y neuroblastoma cells. Interestingly, the phosphorylation of Ser-616 and Ser-637 of Drp1 remains unaffected by the S39A mutation, and mitochondrial bioenergetic profile and cell viability in the S39A mutant were comparable to those observed in the control. This leads us to propose that the serine 39 residue of Drp1 plays a crucial role in mitochondrial distribution through its involvement in the GTPase activity. Furthermore, this amino acid mutation leads to structural anomalies in the mitochondrial network. Taken together, our results contribute to a better understanding of the function of the Drp1 protein.
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Affiliation(s)
- Marvi Ghani
- Department of Medical Chemistry, Faculty of MedicineUniversity of DebrecenHungary
- Doctoral School of Molecular MedicineUniversity of DebrecenHungary
| | - Bernadett Szabó
- Department of Medical Chemistry, Faculty of MedicineUniversity of DebrecenHungary
| | - Mahmoud Alkhatibe
- Department of Medical Chemistry, Faculty of MedicineUniversity of DebrecenHungary
| | - Hailemariam Amsalu
- Department of Medical Chemistry, Faculty of MedicineUniversity of DebrecenHungary
- Doctoral School of Molecular MedicineUniversity of DebrecenHungary
| | - Peleg Zohar
- Department of Medical Chemistry, Faculty of MedicineUniversity of DebrecenHungary
| | - Eszter Anna Janka
- Department of Dermatology, MTA Centre of Excellence, Faculty of MedicineUniversity of DebrecenHungary
- HUN‐REN‐UD Allergology Research GroupUniversity of DebrecenHungary
| | - János András Mótyán
- Department of Biochemistry and Molecular Biology, Faculty of MedicineUniversity of DebrecenHungary
| | - Krisztina Tar
- Department of Medical Chemistry, Faculty of MedicineUniversity of DebrecenHungary
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6
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Jiang A, Kudo K, Gormal RS, Ellis S, Guo S, Wallis TP, Longfield SF, Robinson PJ, Johnson ME, Joensuu M, Meunier FA. Dynamin1 long- and short-tail isoforms exploit distinct recruitment and spatial patterns to form endocytic nanoclusters. Nat Commun 2024; 15:4060. [PMID: 38744819 PMCID: PMC11094030 DOI: 10.1038/s41467-024-47677-8] [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: 03/11/2023] [Accepted: 04/09/2024] [Indexed: 05/16/2024] Open
Abstract
Endocytosis requires a coordinated framework of molecular interactions that ultimately lead to the fission of nascent endocytic structures. How cytosolic proteins such as dynamin concentrate at discrete sites that are sparsely distributed across the plasma membrane remains poorly understood. Two dynamin-1 major splice variants differ by the length of their C-terminal proline-rich region (short-tail and long-tail). Using sptPALM in PC12 cells, neurons and MEF cells, we demonstrate that short-tail dynamin-1 isoforms ab and bb display an activity-dependent recruitment to the membrane, promptly followed by their concentration into nanoclusters. These nanoclusters are sensitive to both Calcineurin and dynamin GTPase inhibitors, and are larger, denser, and more numerous than that of long-tail isoform aa. Spatiotemporal modelling confirms that dynamin-1 isoforms perform distinct search patterns and undergo dimensional reduction to generate endocytic nanoclusters, with short-tail isoforms more robustly exploiting lateral trapping in the generation of nanoclusters compared to the long-tail isoform.
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Affiliation(s)
- Anmin Jiang
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Kye Kudo
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Rachel S Gormal
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Sevannah Ellis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Sikao Guo
- Department of Biophysics, Johns Hopkins University, 3400 N Charles St, Baltimore, MD, 21218, USA
| | - Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Shanley F Longfield
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Phillip J Robinson
- Cell Signalling Unit, Children's Medical Research Institute, The University of Sydney, Sydney, NSW, 2145, Australia
| | - Margaret E Johnson
- Department of Biophysics, Johns Hopkins University, 3400 N Charles St, Baltimore, MD, 21218, USA
| | - Merja Joensuu
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia.
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia.
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7
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Gnyliukh N, Johnson A, Nagel MK, Monzer A, Babić D, Hlavata A, Alotaibi SS, Isono E, Loose M, Friml J. Role of the dynamin-related protein 2 family and SH3P2 in clathrin-mediated endocytosis in Arabidopsis thaliana. J Cell Sci 2024; 137:jcs261720. [PMID: 38506228 PMCID: PMC11112126 DOI: 10.1242/jcs.261720] [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: 10/11/2023] [Accepted: 03/12/2024] [Indexed: 03/21/2024] Open
Abstract
Clathrin-mediated endocytosis (CME) is vital for the regulation of plant growth and development through controlling plasma membrane protein composition and cargo uptake. CME relies on the precise recruitment of regulators for vesicle maturation and release. Homologues of components of mammalian vesicle scission are strong candidates to be part of the scission machinery in plants, but the precise roles of these proteins in this process are not fully understood. Here, we characterised the roles of the plant dynamin-related protein 2 (DRP2) family (hereafter DRP2s) and SH3-domain containing protein 2 (SH3P2), the plant homologue to recruiters of dynamins, such as endophilin and amphiphysin, in CME by combining high-resolution imaging of endocytic events in vivo and characterisation of the purified proteins in vitro. Although DRP2s and SH3P2 arrive similarly late during CME and physically interact, genetic analysis of the sh3p123 triple mutant and complementation assays with non-SH3P2-interacting DRP2 variants suggest that SH3P2 does not directly recruit DRP2s to the site of endocytosis. These observations imply that, despite the presence of many well-conserved endocytic components, plants have acquired a distinct mechanism for CME.
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Affiliation(s)
- Nataliia Gnyliukh
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - Alexander Johnson
- Division of Anatomy, Centre for Anatomy & Cell Biology, Medical University of Vienna, 1090 Vienna, Austria
| | | | - Aline Monzer
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - David Babić
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - Annamaria Hlavata
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - Saqer S. Alotaibi
- Department of Biotechnology, College of Science, Taif University, Taif 21944, Saudi Arabia
| | - Erika Isono
- Department of Biology, University of Konstanz, 78464 Konstanz, Germany
| | - Martin Loose
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - Jiří Friml
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
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8
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Li L, Liu X, Yang S, Li M, Wu Y, Hu S, Wang W, Jiang A, Zhang Q, Zhang J, Ma X, Hu J, Zhao Q, Liu Y, Li D, Hu J, Yang C, Feng W, Wang X. The HEAT repeat protein HPO-27 is a lysosome fission factor. Nature 2024; 628:630-638. [PMID: 38538795 DOI: 10.1038/s41586-024-07249-8] [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: 01/03/2023] [Accepted: 02/28/2024] [Indexed: 04/06/2024]
Abstract
Lysosomes are degradation and signalling centres crucial for homeostasis, development and ageing1. To meet diverse cellular demands, lysosomes remodel their morphology and function through constant fusion and fission2,3. Little is known about the molecular basis of fission. Here we identify HPO-27, a conserved HEAT repeat protein, as a lysosome scission factor in Caenorhabditis elegans. Loss of HPO-27 impairs lysosome fission and leads to an excessive tubular network that ultimately collapses. HPO-27 and its human homologue MROH1 are recruited to lysosomes by RAB-7 and enriched at scission sites. Super-resolution imaging, negative-staining electron microscopy and in vitro reconstitution assays reveal that HPO-27 and MROH1 self-assemble to mediate the constriction and scission of lysosomal tubules in worms and mammalian cells, respectively, and assemble to sever supported membrane tubes in vitro. Loss of HPO-27 affects lysosomal morphology, integrity and degradation activity, which impairs animal development and longevity. Thus, HPO-27 and MROH1 act as self-assembling scission factors to maintain lysosomal homeostasis and function.
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Affiliation(s)
- Letao Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Conservation and Utilization of Bio-Resources in Yunnan, and Center for Life Sciences, School of Life Sciences, Yunnan University, Kunming, China
| | - Xilu Liu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Shanshan Yang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Meijiao Li
- State Key Laboratory of Conservation and Utilization of Bio-Resources in Yunnan, and Center for Life Sciences, School of Life Sciences, Yunnan University, Kunming, China
- Southwest United Graduate School, Kunming, China
| | - Yanwei Wu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Siqi Hu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Wenjuan Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Amin Jiang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Qianqian Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Junbing Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Xiaoli Ma
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Junyan Hu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Qiaohong Zhao
- State Key Laboratory of Conservation and Utilization of Bio-Resources in Yunnan, and Center for Life Sciences, School of Life Sciences, Yunnan University, Kunming, China
| | - Yubing Liu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Dong Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Junjie Hu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Chonglin Yang
- State Key Laboratory of Conservation and Utilization of Bio-Resources in Yunnan, and Center for Life Sciences, School of Life Sciences, Yunnan University, Kunming, China
- Southwest United Graduate School, Kunming, China
| | - Wei Feng
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
| | - Xiaochen Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
- Southwest United Graduate School, Kunming, China.
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, China.
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9
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Božinović K, Nestić D, Grellier E, Raddi N, Cornilleau G, Ambriović-Ristov A, Benihoud K, Majhen D. NGR-bearing human adenovirus type 5 infects cells in flotillin- or caveolin-mediated manner depending on the NGR insertion site. BIOMATERIALS ADVANCES 2023; 155:213681. [PMID: 37944448 DOI: 10.1016/j.bioadv.2023.213681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 10/10/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023]
Abstract
Human adenoviruses represent attractive candidates for the design of cancer gene therapy vectors. Modification of adenovirus tropism by incorporating a targeting ligand into the adenovirus capsid proteins allows retargeting of adenovirus towards the cells of interest. Human adenovirus type 5 (HAdV-C5) bearing NGR containing peptide (CNGRCVSGCAGRC) inserted into the fiber (AdFNGR) or the hexon (AdHNGR) protein demonstrated an increased transduction of endothelial cells showing expression of aminopeptidase N, also known as CD13, and αvβ3 integrin both present on tumor vasculature, indicating that NGR-bearing adenoviruses could be used as tools for anti-angiogenic cancer therapy. Here we investigated how AdFNGR and AdHNGR infect cells lacking HAdV-C5 primary receptor, coxsackie and adenovirus receptor, and we showed that both AFNGR and AdHNGR enter cells by dynamin- and lipid raft-mediated endocytosis, while clathrin is not required for endocytosis of these viruses. We present evidence that productive infection of both AdFNGR and AdHNGR involves lipid rafts, with usage of flotillin-mediated cell entry for AdFNGR and limited role of caveolin in AdHNGR transduction efficiency. Lipid rafts play important role in angiogenesis and process of metastasis. Therefore, the ability of AdFNGR and AdHNGR to use lipid raft-dependent endocytosis, involving respectively flotillin- or caveolin-mediated pathway, could give them an advantage in targeting tumor cells lacking HAdV-C5 primary receptor.
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Affiliation(s)
- Ksenija Božinović
- Laboratory for Cell Biology and Signalling, Division of Molecular Biology, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Davor Nestić
- Laboratory for Cell Biology and Signalling, Division of Molecular Biology, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Elodie Grellier
- Université Paris-Saclay, CNRS, Institut Gustave Roussy, Metabolic and Systemic Aspects of Oncogenesis for New Therapeutic Approaches, 94805 Villejuif, France
| | - Najat Raddi
- Université Paris-Saclay, CNRS, Institut Gustave Roussy, Metabolic and Systemic Aspects of Oncogenesis for New Therapeutic Approaches, 94805 Villejuif, France
| | - Gaétan Cornilleau
- Université Paris-Saclay, CNRS, Institut Gustave Roussy, Metabolic and Systemic Aspects of Oncogenesis for New Therapeutic Approaches, 94805 Villejuif, France
| | - Andreja Ambriović-Ristov
- Laboratory for Cell Biology and Signalling, Division of Molecular Biology, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Karim Benihoud
- Université Paris-Saclay, CNRS, Institut Gustave Roussy, Metabolic and Systemic Aspects of Oncogenesis for New Therapeutic Approaches, 94805 Villejuif, France
| | - Dragomira Majhen
- Laboratory for Cell Biology and Signalling, Division of Molecular Biology, Ruđer Bošković Institute, 10000 Zagreb, Croatia; Université Paris-Saclay, CNRS, Institut Gustave Roussy, Metabolic and Systemic Aspects of Oncogenesis for New Therapeutic Approaches, 94805 Villejuif, France.
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10
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Nakakura T, Tanaka H, Suzuki T. Caveolae-mediated endocytosis pathway regulates endothelial fenestra homeostasis in the rat pituitary. Biochem Biophys Res Commun 2023; 675:177-183. [PMID: 37506534 DOI: 10.1016/j.bbrc.2023.07.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023]
Abstract
Endothelial fenestrae are transcellular pores separated by diaphragms formed by plasmalemma vesicle-associated proteins (PLVAP) and function as channels for peptide hormones and other substances. Caveola, a key regulator of clathrin-independent endocytosis, may be involved in the invagination and fusion of plasma membranes, which are essential for fenestra formation. In this study, we first found that caveolin-1 and -2, the major components of caveolae, was localized in fenestrated endothelial cells in the anterior lobe of the rat pituitary by immunohistochemistry. As we also observed caveolae in the endothelial cells of the anterior lobe of the rat pituitary by transmission electron microscopy, we studied the relationship between the caveolae-mediated endocytosis pathway and fenestrae structure in cultured endothelial cells isolated from the anterior lobe of the rat pituitary (CECAL) by immunofluorescence staining and scanning electron microscopy. The inhibition of caveolae-mediated endocytosis by genistein enlarged the PLVAP-positive oval-shaped structure that represented the sieve plate and induced the formation of a doughnut-shaped bulge around the fenestra in CECAL. In contrast, the acceleration of caveolae-mediated endocytosis by okadaic acid induced the diffusion of PLVAP-positive signals in the cytoplasm and reduced the number of fenestrae in CECAL. These results indicate that the caveolae-mediated endocytosis pathway is involved in the fenestra homeostasis in the fenestrated endothelial cells of the rat pituitary.
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Affiliation(s)
- Takashi Nakakura
- Department of Anatomy, Teikyo University School of Medicine, 2-11-1 Kaga Itabashi-Ku, Tokyo, 173-8605, Japan.
| | - Hideyuki Tanaka
- Department of Anatomy, Teikyo University School of Medicine, 2-11-1 Kaga Itabashi-Ku, Tokyo, 173-8605, Japan
| | - Takeshi Suzuki
- Department of Biology, Sapporo Medical University, Sapporo, 060-8556, Japan
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11
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Bonnycastle K, Dobson KL, Blumrich EM, Gajbhiye A, Davenport EC, Pronot M, Steinruecke M, Trost M, Gonzalez-Sulser A, Cousin MA. Reversal of cell, circuit and seizure phenotypes in a mouse model of DNM1 epileptic encephalopathy. Nat Commun 2023; 14:5285. [PMID: 37648685 PMCID: PMC10468497 DOI: 10.1038/s41467-023-41035-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 08/17/2023] [Indexed: 09/01/2023] Open
Abstract
Dynamin-1 is a large GTPase with an obligatory role in synaptic vesicle endocytosis at mammalian nerve terminals. Heterozygous missense mutations in the dynamin-1 gene (DNM1) cause a novel form of epileptic encephalopathy, with pathogenic mutations clustering within regions required for its essential GTPase activity. We reveal the most prevalent pathogenic DNM1 mutation, R237W, disrupts dynamin-1 enzyme activity and endocytosis when overexpressed in central neurons. To determine how this mutation impacted cell, circuit and behavioural function, we generated a mouse carrying the R237W mutation. Neurons from heterozygous mice display dysfunctional endocytosis, in addition to altered excitatory neurotransmission and seizure-like phenotypes. Importantly, these phenotypes are corrected at the cell, circuit and in vivo level by the drug, BMS-204352, which accelerates endocytosis. Here, we demonstrate a credible link between dysfunctional endocytosis and epileptic encephalopathy, and importantly reveal that synaptic vesicle recycling may be a viable therapeutic target for monogenic intractable epilepsies.
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Affiliation(s)
- Katherine Bonnycastle
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK.
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK.
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK.
- Service de Génétique Médicale, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Université de Montréal, Montreal, QC, Canada.
| | - Katharine L Dobson
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Eva-Maria Blumrich
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Akshada Gajbhiye
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, NE2 4HH, Newcastle upon Tyne, UK
| | - Elizabeth C Davenport
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Marie Pronot
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Moritz Steinruecke
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Matthias Trost
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, NE2 4HH, Newcastle upon Tyne, UK
| | - Alfredo Gonzalez-Sulser
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK
| | - Michael A Cousin
- Centre for Discovery Brain Sciences, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK.
- Simons Initiative for the Developing Brain, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK.
- Muir Maxwell Epilepsy Centre, Hugh Robson Building, George Square, University of Edinburgh, EH8 9XD, Edinburgh, Scotland, UK.
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12
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Harms FL, Weiss D, Lisfeld J, Alawi M, Kutsche K. A deep intronic variant in DNM1 in a patient with developmental and epileptic encephalopathy creates a splice acceptor site and affects only transcript variants including exon 10a. Neurogenetics 2023; 24:171-180. [PMID: 37039969 DOI: 10.1007/s10048-023-00716-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 03/28/2023] [Indexed: 04/12/2023]
Abstract
DNM1 developmental and epileptic encephalopathy (DEE) is characterized by severe to profound intellectual disability, hypotonia, movement disorder, and refractory epilepsy, typically presenting with infantile spasms. Most of the affected individuals had de novo missense variants in DNM1. DNM1 undergoes alternative splicing that results in expression of six different transcript variants. One alternatively spliced region affects the tandemly arranged exons 10a and 10b, producing isoforms DNM1A and DNM1B, respectively. Pathogenic variants in the DNM1 coding region affect all transcript variants. Recently, a de novo DNM1 NM_001288739.1:c.1197-8G > A variant located in intron 9 has been reported in several unrelated individuals with DEE that causes in-frame insertion of two amino acids and leads to disease through a dominant-negative mechanism. We report on a patient with DEE and a de novo DNM1 variant NM_001288739.2:c.1197-46C > G in intron 9, upstream of exon 10a. By RT-PCR and Sanger sequencing using fibroblast-derived cDNA of the patient, we identified aberrantly spliced DNM1 mRNAs with exon 9 spliced to the last 45 nucleotides of intron 9 followed by exon 10a (NM_001288739.2:r.1196_1197ins[1197-1_1197-45]). The encoded DNM1A mutant is predicted to contain 15 novel amino acids between Ile398 and Arg399 [NP_001275668.1:p.(Ile398_Arg399ins15)] and likely functions in a dominant-negative manner, similar to other DNM1 mutants. Our data confirm the importance of the DNM1 isoform A for normal human brain function that is underscored by previously reported predominant expression of DMN1A transcripts in pediatric brain, functional differences of the mouse Dnm1a and Dnm1b isoforms, and the Dnm1 fitful mouse, an epilepsy mouse model.
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Affiliation(s)
- Frederike L Harms
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Deike Weiss
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jasmin Lisfeld
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Malik Alawi
- Bioinformatics Core, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kerstin Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
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13
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Arlt H, Raman B, Filali-Mouncef Y, Hu Y, Leytens A, Hardenberg R, Guimarães R, Kriegenburg F, Mari M, Smaczynska-de Rooij II, Ayscough KR, Dengjel J, Ungermann C, Reggiori F. The dynamin Vps1 mediates Atg9 transport to the sites of autophagosome formation. J Biol Chem 2023; 299:104712. [PMID: 37060997 DOI: 10.1016/j.jbc.2023.104712] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/14/2023] [Accepted: 04/06/2023] [Indexed: 04/17/2023] Open
Abstract
Autophagy is a key process in eukaryotes to maintain cellular homeostasis by delivering cellular components to lysosomes/vacuoles for degradation and reuse of the resulting metabolites. Membrane rearrangements and trafficking events are mediated by the core machinery of autophagy-related (Atg) proteins, which carry out a variety of functions. How Atg9, a lipid scramblase and the only conserved transmembrane protein within this core Atg machinery, is trafficked during autophagy remained largely unclear. Here, we addressed this question in yeast Saccharomyces cerevisiae and found that retromer complex and dynamin Vps1 mutants alter Atg9 subcellular distribution and severely impair the autophagic flux by affecting two separate autophagy steps. We provide evidence that Vps1 interacts with Atg9 at Atg9 reservoirs. In the absence of Vps1, Atg9 fails to reach the sites of autophagosome formation, and this results in an autophagy defect. The function of Vps1 in autophagy requires its GTPase activity. Moreover, Vps1 point mutants associated with human diseases such as microcytic anemia and Charcot-Marie-Tooth are unable to sustain autophagy and affect Atg9 trafficking. Together, our data provide novel insights on the role of dynamins in Atg9 trafficking and suggest that a defect in this autophagy step could contribute to severe human pathologies.
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Affiliation(s)
- Henning Arlt
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; University of Osnabrück, Department of Biology/Chemistry, Biochemistry section, Barbarastrasse 13, 49076 Osnabrück, Germany
| | - Babu Raman
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Yasmina Filali-Mouncef
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Yan Hu
- Department of Biomedicine, Aarhus University, Ole Worms Allé 4, 8000 Aarhus C, Denmark
| | - Alexandre Leytens
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Ralph Hardenberg
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rodrigo Guimarães
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Franziska Kriegenburg
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Muriel Mari
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedicine, Aarhus University, Ole Worms Allé 4, 8000 Aarhus C, Denmark
| | | | - Kathryn R Ayscough
- Department of Biomedical Sciences, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Jörn Dengjel
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Christian Ungermann
- University of Osnabrück, Department of Biology/Chemistry, Biochemistry section, Barbarastrasse 13, 49076 Osnabrück, Germany
| | - Fulvio Reggiori
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedicine, Aarhus University, Ole Worms Allé 4, 8000 Aarhus C, Denmark; Aarhus Institute of Advanced Studies (AIAS), Aarhus University, Høegh-Guldbergs Gade 6B, 8000 Aarhus C, Denmark.
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14
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Shen ZF, Li L, Zhu XM, Liu XH, Klionsky DJ, Lin FC. Current opinions on mitophagy in fungi. Autophagy 2023; 19:747-757. [PMID: 35793406 PMCID: PMC9980689 DOI: 10.1080/15548627.2022.2098452] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 11/02/2022] Open
Abstract
Mitophagy, as one of the most important cellular processes to ensure quality control of mitochondria, aims at transporting damaged, aging, dysfunctional or excess mitochondria to vacuoles (plants and fungi) or lysosomes (mammals) for degradation and recycling. The normal functioning of mitophagy is critical for cellular homeostasis from yeasts to humans. Although the role of mitophagy has been well studied in mammalian cells and in certain model organisms, especially the budding yeast Saccharomyces cerevisiae, our understanding of its significance in other fungi, particularly in pathogenic filamentous fungi, is still at the preliminary stage. Recent studies have shown that mitophagy plays a vital role in spore production, vegetative growth and virulence of pathogenic fungi, which are very different from its roles in mammal and yeast. In this review, we summarize the functions of mitophagy for mitochondrial quality and quantity control, fungal growth and pathogenesis that have been reported in the field of molecular biology over the past two decades. These findings may help researchers and readers to better understand the multiple functions of mitophagy and provide new perspectives for the study of mitophagy in fungal pathogenesis.Abbreviations: AIM/LIR: Atg8-family interacting motif/LC3-interacting region; BAR: Bin-Amphiphysin-Rvs; BNIP3: BCL2 interacting protein 3; CK2: casein kinase 2; Cvt: cytoplasm-to-vacuole targeting; ER: endoplasmic reticulum; IMM: inner mitochondrial membrane; mETC: mitochondrial electron transport chain; OMM: outer mitochondrial membrane; OPTN: optineurin; PAS: phagophore assembly site; PD: Parkinson disease; PE: phosphatidylethanolamine; PHB2: prohibitin 2; PX: Phox homology; ROS, reactive oxygen species; TM: transmembrane.
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Affiliation(s)
- Zi-Fang Shen
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China
| | - Lin Li
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
| | - Xue-Ming Zhu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
| | - Xiao-Hong Liu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China
| | - Daniel J. Klionsky
- Life Sciences Institute and Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Fu-Cheng Lin
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China
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15
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Paul D, Stern O, Vallis Y, Dhillon J, Buchanan A, McMahon H. Cell surface protein aggregation triggers endocytosis to maintain plasma membrane proteostasis. Nat Commun 2023; 14:947. [PMID: 36854675 PMCID: PMC9974993 DOI: 10.1038/s41467-023-36496-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 02/03/2023] [Indexed: 03/02/2023] Open
Abstract
The ability of cells to manage consequences of exogenous proteotoxicity is key to cellular homeostasis. While a plethora of well-characterised machinery aids intracellular proteostasis, mechanisms involved in the response to denaturation of extracellular proteins remain elusive. Here we show that aggregation of protein ectodomains triggers their endocytosis via a macroendocytic route, and subsequent lysosomal degradation. Using ERBB2/HER2-specific antibodies we reveal that their cross-linking ability triggers specific and fast endocytosis of the receptor, independent of clathrin and dynamin. Upon aggregation, canonical clathrin-dependent cargoes are redirected into the aggregation-dependent endocytosis (ADE) pathway. ADE is an actin-driven process, which morphologically resembles macropinocytosis. Physical and chemical stress-induced aggregation of surface proteins also triggers ADE, facilitating their degradation in the lysosome. This study pinpoints aggregation of extracellular domains as a trigger for rapid uptake and lysosomal clearance which besides its proteostatic function has potential implications for the uptake of pathological protein aggregates and antibody-based therapies.
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Affiliation(s)
- David Paul
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Omer Stern
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Yvonne Vallis
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Jatinder Dhillon
- AstraZeneca, R&D BioPharma, Antibody Discovery & Protein Engineering, Granta Park, Cambridge, CB21 6GH, UK
| | - Andrew Buchanan
- AstraZeneca, R&D BioPharma, Antibody Discovery & Protein Engineering, Granta Park, Cambridge, CB21 6GH, UK
| | - Harvey McMahon
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
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16
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Mani I, Singh V. An overview of receptor endocytosis and signaling. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 194:1-18. [PMID: 36631188 DOI: 10.1016/bs.pmbts.2022.06.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Endocytosis is a cellular process which mediates receptor internalization, nutrient uptake, and the regulation of cell signaling. Microorganisms (many bacteria and viruses) and toxins also use the same process and enter the cells. Generally, endocytosis is considered in the three forms such as phagocytosis (cell eating), pinocytosis (cell drinking), and highly selective receptor-mediated endocytosis (clathrin-dependent and independent). Several endocytic routes exist in an analogous, achieving diverse functions. Most studies on endocytosis have used transformed cells in culture. To visualize the receptor internalization, trafficking, and signaling in subcellular organelles, a green fluorescent protein-tagged receptor has been utilized. It also helps to visualize the endocytosis effects in live-cell imaging. Confocal laser microscopy increases our understanding of receptor endocytosis and signaling. Site-directed mutagenesis studies demonstrated that many short-sequence motifs of the cytoplasmic domain of receptors significantly play a vital role in receptor internalization, subcellular trafficking, and signaling. However, other factors also regulate receptor internalization through clathrin-coated vesicles. Receptor endocytosis can occur through clathrin-dependent and clathrin-independent pathways. This chapter briefly discusses the internalization, trafficking, and signaling of various receptors in normal conditions. In addition, it also highlights the malfunction of the receptor in disease conditions.
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Affiliation(s)
- Indra Mani
- Department of Microbiology, Gargi College, University of Delhi, New Delhi, India.
| | - Vijai Singh
- Department of Biosciences, School of Science, Indrashil University, Rajpur, Mehsana, Gujarat, India
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17
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Millard RS, Bickley LK, Bateman KS, Verbruggen B, Farbos A, Lange A, Moore KA, Stentiford GD, Tyler CR, van Aerle R, Santos EM. Resistance to white spot syndrome virus in the European shore crab is associated with suppressed virion trafficking and heightened immune responses. Front Immunol 2022; 13:1057421. [PMID: 36636327 PMCID: PMC9831657 DOI: 10.3389/fimmu.2022.1057421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/01/2022] [Indexed: 12/28/2022] Open
Abstract
Introduction All decapod crustaceans are considered potentially susceptible to White Spot Syndrome Virus (WSSV) infection, but the degree of White Spot Disease (WSD) susceptibility varies widely between species. The European shore crab Carcinus maenas can be infected with the virus for long periods of time without signs of disease. Given the high mortality rate of susceptible species, the differential susceptibility of these resistant hosts offers an opportunity to investigate mechanisms of disease resistance. Methods Here, the temporal transcriptional responses (mRNA and miRNA) of C. maenas following WSSV injection were analysed and compared to a previously published dataset for the highly WSSV susceptible Penaeus vannamei to identify key genes, processes and pathways contributing to increased WSD resistance. Results We show that, in contrast to P. vannamei, the transcriptional response during the first 2 days following WSSV injection in C. maenas is limited. During the later time points (7 days onwards), two groups of crabs were identified, a recalcitrant group where no replication of the virus occurred, and a group where significant viral replication occurred, with the transcriptional profiles of the latter group resembling those of WSSV-susceptible species. We identify key differences in the molecular responses of these groups to WSSV injection. Discussion We propose that increased WSD resistance in C. maenas may result from impaired WSSV endocytosis due to the inhibition of internal vesicle budding by dynamin-1, and a delay in movement to the nucleus caused by the downregulation of cytoskeletal transcripts required for WSSV cytoskeleton docking, during early stages of the infection. This response allows resistant hosts greater time to fine-tune immune responses associated with miRNA expression, apoptosis and the melanisation cascade to defend against, and clear, invading WSSV. These findings suggest that the initial stages of infection are key to resistance to WSSV in the crab and highlight possible pathways that could be targeted in farmed crustacean to enhance resistance to WSD.
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Affiliation(s)
- Rebecca S. Millard
- International Centre of Excellence for Aquatic Animal Health, Cefas Laboratory, Weymouth, United Kingdom,Sustainable Aquaculture Futures, University of Exeter, Exeter, United Kingdom,*Correspondence: Rebecca S. Millard, ; Eduarda M. Santos,
| | - Lisa K. Bickley
- Sustainable Aquaculture Futures, University of Exeter, Exeter, United Kingdom,Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Kelly S. Bateman
- International Centre of Excellence for Aquatic Animal Health, Cefas Laboratory, Weymouth, United Kingdom,Sustainable Aquaculture Futures, University of Exeter, Exeter, United Kingdom
| | - Bas Verbruggen
- Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Audrey Farbos
- University of Exeter Sequencing Facility, Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Anke Lange
- Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Karen A. Moore
- University of Exeter Sequencing Facility, Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Grant D. Stentiford
- International Centre of Excellence for Aquatic Animal Health, Cefas Laboratory, Weymouth, United Kingdom,Sustainable Aquaculture Futures, University of Exeter, Exeter, United Kingdom
| | - Charles R. Tyler
- Sustainable Aquaculture Futures, University of Exeter, Exeter, United Kingdom,Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Ronny van Aerle
- International Centre of Excellence for Aquatic Animal Health, Cefas Laboratory, Weymouth, United Kingdom,Sustainable Aquaculture Futures, University of Exeter, Exeter, United Kingdom
| | - Eduarda M. Santos
- Sustainable Aquaculture Futures, University of Exeter, Exeter, United Kingdom,Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom,*Correspondence: Rebecca S. Millard, ; Eduarda M. Santos,
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18
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Odell LR, Robertson MJ, Young KA, McGeachie AB, Quan A, Robinson PJ, McCluskey A. Prodrugs of the Archetypal Dynamin Inhibitor Bis-T-22. ChemMedChem 2022; 17:e202200400. [PMID: 36351775 PMCID: PMC10947042 DOI: 10.1002/cmdc.202200400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 10/06/2022] [Indexed: 11/11/2022]
Abstract
The Bis-T series of compounds comprise some of the most potent inhibitors of dynamin GTPase activity yet reported, e. g., (2E,2'E)-N,N'-(propane-1,3-diyl)bis(2-cyano-3-(3,4-dihydroxyphenyl)acrylamide) (2), Bis-T-22. The catechol moieties are believed to limit cell permeability, rendering these compounds largely inactive in cells. To solve this problem, a prodrug strategy was envisaged and eight ester analogues were synthesised. The shortest and bulkiest esters (acetate and butyl/tert-butyl) were found to be insoluble under physiological conditions, whilst the remaining five were soluble and stable under these conditions. These five were analysed for plasma stability and half-lives ranged from ∼2.3 min (propionic ester 4), increasing with size and bulk, to greater than 24 hr (dimethyl carbamate 10). Similar profiles where observed with the rate of formation of Bis-T-22 with half-lives ranging from ∼25 mins (propionic ester 4). Propionic ester 4 was chosen to undergo further testing and was found to inhibit endocytosis in a dose-dependent manner with IC50 ∼8 μM, suggesting this compound is able to effectively cross the cell membrane where it is rapidly hydrolysed to the desired Bis-T-22 parent compound.
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Affiliation(s)
- Luke R. Odell
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
- Present address: Department of Medicinal ChemistryUppsala UniversityBox 57475123UppsalaSweden
| | - Mark J Robertson
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
- Present address: Chemistry, College of Science & EngineeringJames Cook UniversityTownsvilleQLD 4814Australia
| | - Kelly A Young
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
| | - Andrew B. McGeachie
- Cell Signalling UnitChildren's Medical Research InstituteThe University of Sydney214 Hawkesbury RoadWestmeadNSW 2145Australia
| | - Annie Quan
- Cell Signalling UnitChildren's Medical Research InstituteThe University of Sydney214 Hawkesbury RoadWestmeadNSW 2145Australia
| | - Phillip J. Robinson
- Cell Signalling UnitChildren's Medical Research InstituteThe University of Sydney214 Hawkesbury RoadWestmeadNSW 2145Australia
| | - Adam McCluskey
- The University of NewcastleUniversity DriveCallaghanNSW 2308Australia
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19
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Regulation of fenestra formation via actin-dynamin2 interaction in rat pituitary endothelial cells. Cell Tissue Res 2022; 390:441-451. [PMID: 36102975 DOI: 10.1007/s00441-022-03685-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 09/08/2022] [Indexed: 12/14/2022]
Abstract
Endothelial fenestrae are transcellular pores divided by a diaphragm consisting of plasmalemma vesicle-associated protein (PLVAP). They function as a channel for peptide hormones and other substances. Invagination of the plasma membrane is necessary for the fenestra formation. The actin cytoskeleton is essential for scission of endocytic vesicles from the invaginated plasma membrane. Therefore, we examined the involvement of the actin cytoskeleton in fenestra formation in cultured endothelial cells isolated from the anterior lobe (AL) of the rat pituitary, using immunofluorescence and scanning electron microscopy. Inhibition of polymerization and depolymerization of the actin cytoskeleton by latrunculin A and jasplakinolide, respectively, remarkably increased the PLVAP-positive sieve plate area and number of fenestrae. Jasplakinolide significantly affected the arrangement of the fenestra on the cell surface, resulting in parallel serpentine furrows of the fenestra. These results suggest that the actin cytoskeleton not only induces fenestra formation but also regulates cell arrangement. Dynamin is a scission protein of the invaginated plasma membrane and interacts with the actin cytoskeleton. We found that dynamin2 is mainly expressed in the endothelial cells of the rat AL. We then investigated the function of dynamin2 by the treatment with dyngo-4a, a potent inhibitor of dynamin1 and dynamin2, on the fenestra formation. As a result, the PLVAP-positive area is significantly increased by the treatment. These results show that the actin-dynamin2 interaction is essential for the control of the fenestra formation in endothelial cells of rat AL. In conclusion, the actin cytoskeleton and dynamin2 function as regulators of endothelial fenestra formation.
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20
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Pseudokinase NRP1 facilitates endocytosis of transferrin in the African trypanosome. Sci Rep 2022; 12:18572. [PMID: 36329148 PMCID: PMC9633767 DOI: 10.1038/s41598-022-22054-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
Trypanosoma brucei causes human African trypanosomiasis (HAT) and nagana in cattle. During infection of a vertebrate, endocytosis of host transferrin (Tf) is important for viability of the parasite. The majority of proteins involved in trypanosome endocytosis of Tf are unknown. Here we identify pseudokinase NRP1 (Tb427tmp.160.4770) as a regulator of Tf endocytosis. Genetic knockdown of NRP1 inhibited endocytosis of Tf without blocking uptake of bovine serum albumin. Binding of Tf to the flagellar pocket was not affected by knockdown of NRP1. However the quantity of Tf per endosome dropped significantly, consistent with NRP1 promoting robust capture and/or retention of Tf in vesicles. NRP1 is involved in motility of Tf-laden vesicles since distances between endosomes and the kinetoplast were reduced after knockdown of the gene. In search of possible mediators of NRP1 modulation of Tf endocytosis, the gene was knocked down and the phosphoproteome analyzed. Phosphorylation of protein kinases forkhead, NEK6, and MAPK10 was altered, in addition to EpsinR, synaptobrevin and other vesicle-associated proteins predicted to be involved in endocytosis. These candidate proteins may link NRP1 functionally either to protein kinases or to vesicle-associated proteins.
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21
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Liu L, Xiong Q, Xie C, Pincet F, Lin C. Actuating tension-loaded DNA clamps drives membrane tubulation. SCIENCE ADVANCES 2022; 8:eadd1830. [PMID: 36223466 PMCID: PMC9555772 DOI: 10.1126/sciadv.add1830] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 08/24/2022] [Indexed: 06/16/2023]
Abstract
Membrane dynamics in living organisms can arise from proteins adhering to, assembling on, and exerting force on cell membranes. Programmable synthetic materials, such as self-assembled DNA nanostructures, offer the capability to drive membrane-remodeling events that resemble protein-mediated dynamics but with user-defined outcomes. An illustrative example is the tubular deformation of liposomes by DNA nanostructures with purposely designed shapes, surface modifications, and self-assembling properties. However, stimulus-responsive membrane tubulation mediated by DNA reconfiguration remains challenging. Here, we present the triggered formation of membrane tubes in response to specific DNA signals that actuate membrane-bound DNA clamps from an open state to various predefined closed states, releasing prestored energy to activate membrane deformation. We show that the timing and efficiency of vesicle tubulation, as well as the membrane tube widths, are modulated by the conformational change of DNA clamps, marking a solid step toward spatiotemporal control of membrane dynamics in an artificial system.
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Affiliation(s)
- Longfei Liu
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Qiancheng Xiong
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Chun Xie
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Frederic Pincet
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
- Laboratoire de Physique de l’Ecole Normale Supérieure, Ecole Normale Supérieure (ENS), Université Paris Sciences et Lettres (PSL), CNRS, Sorbonne Université, Université Paris Cité, Paris, France
| | - Chenxiang Lin
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
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22
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Fujise K, Noguchi S, Takeda T. Centronuclear Myopathy Caused by Defective Membrane Remodelling of Dynamin 2 and BIN1 Variants. Int J Mol Sci 2022; 23:ijms23116274. [PMID: 35682949 PMCID: PMC9181712 DOI: 10.3390/ijms23116274] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 05/31/2022] [Accepted: 06/01/2022] [Indexed: 02/01/2023] Open
Abstract
Centronuclear myopathy (CNM) is a congenital myopathy characterised by centralised nuclei in skeletal myofibers. T-tubules, sarcolemmal invaginations required for excitation-contraction coupling, are disorganised in the skeletal muscles of CNM patients. Previous studies showed that various endocytic proteins are involved in T-tubule biogenesis and their dysfunction is tightly associated with CNM pathogenesis. DNM2 and BIN1 are two causative genes for CNM that encode essential membrane remodelling proteins in endocytosis, dynamin 2 and BIN1, respectively. In this review, we overview the functions of dynamin 2 and BIN1 in T-tubule biogenesis and discuss how their dysfunction in membrane remodelling leads to CNM pathogenesis.
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Affiliation(s)
- Kenshiro Fujise
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06520-8001, USA;
| | - Satoru Noguchi
- National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Tokyo 187-8502, Japan;
| | - Tetsuya Takeda
- Department of Biochemistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Shikata-cho 2-5-1, Kita-ku, Okayama 700-8558, Japan
- Correspondence: ; Tel.: +81-86-235-7125; Fax: +81-86-235-7126
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23
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Inositol hexakisphosphate primes syndapin I/PACSIN 1 activation in endocytosis. Cell Mol Life Sci 2022; 79:286. [PMID: 35534740 PMCID: PMC9085685 DOI: 10.1007/s00018-022-04305-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 04/08/2022] [Accepted: 04/12/2022] [Indexed: 02/08/2023]
Abstract
Endocytosis is controlled by a well-orchestrated molecular machinery, where the individual players as well as their precise interactions are not fully understood. We now show that syndapin I/PACSIN 1 is expressed in pancreatic β cells and that its knockdown abrogates β cell endocytosis leading to disturbed plasma membrane protein homeostasis, as exemplified by an elevated density of L-type Ca2+ channels. Intriguingly, inositol hexakisphosphate (InsP6) activates casein kinase 2 (CK2) that phosphorylates syndapin I/PACSIN 1, thereby promoting interactions between syndapin I/PACSIN 1 and neural Wiskott–Aldrich syndrome protein (N-WASP) and driving β cell endocytosis. Dominant-negative interference with endogenous syndapin I/PACSIN 1 protein complexes, by overexpression of the syndapin I/PACSIN 1 SH3 domain, decreases InsP6-stimulated endocytosis. InsP6 thus promotes syndapin I/PACSIN 1 priming by CK2-dependent phosphorylation, which endows the syndapin I/PACSIN 1 SH3 domain with the capability to interact with the endocytic machinery and thereby initiate endocytosis, as exemplified in β cells.
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24
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Smith KP, Lee W, Tonelli M, Lee Y, Light SH, Cornilescu G, Chakravarthy S. Solution structure and dynamics of the mitochondrial-targeted GTPase-activating protein (GAP) VopE by an integrated NMR/SAXS approach. Protein Sci 2022; 31:e4282. [PMID: 35137487 PMCID: PMC9047041 DOI: 10.1002/pro.4282] [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: 09/29/2021] [Revised: 01/17/2022] [Accepted: 01/27/2022] [Indexed: 11/11/2022]
Abstract
The bacterial pathogen Vibrio cholerae use a type III secretion system to inject effector proteins into a host cell. Recently, a putative Toxic GTPase Activating Protein (ToxGAP) called Vibrio outer protein E (VopE) was identified as a T3SS substrate and virulence factor that affected host mitochondrial dynamics and immune response. However, biophysical and structural characterization has been absent. Here, we describe solution NMR structure of the putative GTPase-activating protein (GAP) domain (73-204) of VopE. Using size exclusion chromatography coupled with small-angle x-ray scattering and residual dipolar coupling data, we restrained the MD process to efficiently determine the overall fold and improve the quality of the output calculated structures. Comparing the structure of VopE with other ToxGAP's revealed a similar overall fold with several features unique to VopE. Specifically, the "Bulge 1," α1 helix, and noteworthy "backside linker" elements on the N-terminus are dissimilar to the other ToxGAP's. By using NMR relaxation dispersion experiments, we demonstrate that these regions undergo motions on a > 6 s-1 timescale. Based on the disposition of these mobile regions relative to the putative catalytic arginine residue, we hypothesize that the protein may undergo structural changes to bind cognate GTPases.
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Affiliation(s)
- Kyle P. Smith
- Department of Cell & Developmental BiologyNorthwestern University ChicagoIllinoisUSA
- Xilio TherapeuticsWalthamMassachusettsUSA
| | - Woonghee Lee
- Department of ChemistryUniversity of Colorado‐DenverDenverColoradoUSA
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison, Department of BiochemistryUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Yeongjoon Lee
- Department of ChemistryUniversity of Colorado‐DenverDenverColoradoUSA
| | - Samuel H. Light
- Department of MicrobiologyUniversity of ChicagoChicagoIllinoisUSA
| | - Gabriel Cornilescu
- Advanced Technology Research Facility, Frederick National Laboratory for Cancer ResearchLeidos Biomedical Research, Inc., National Cancer Institute, National Institutes of HealthFrederickMarylandUSA
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25
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Dephospho-dynamin 1 coupled to activity-dependent bulk endocytosis participates in epileptic seizure in primary hippocampal neurons. Epilepsy Res 2022; 182:106915. [DOI: 10.1016/j.eplepsyres.2022.106915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/23/2022] [Accepted: 03/27/2022] [Indexed: 11/21/2022]
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26
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Tian X, Bunda P, Ishibe S. Podocyte Endocytosis in Regulating the Glomerular Filtration Barrier. Front Med (Lausanne) 2022; 9:801837. [PMID: 35223901 PMCID: PMC8866310 DOI: 10.3389/fmed.2022.801837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/06/2022] [Indexed: 12/26/2022] Open
Abstract
Endocytosis is a mechanism that internalizes and recycles plasma membrane components and transmembrane receptors via vesicle formation, which is mediated by clathrin-dependent and clathrin-independent signaling pathways. Podocytes are specialized, terminally differentiated epithelial cells in the kidney, located on the outermost layer of the glomerulus. These cells play an important role in maintaining the integrity of the glomerular filtration barrier in conjunction with the adjacent basement membrane and endothelial cell layers within the glomerulus. An intact podocyte endocytic machinery appears to be necessary for maintaining podocyte function. De novo pathologic human genetic mutations and loss-of-function studies of critical podocyte endocytosis genes in genetically engineered mouse models suggest that this pathway contributes to the pathophysiology of development and progression of proteinuria in chronic kidney disease. Here, we review the mechanism of cellular endocytosis and its regulation in podocyte injury in the context of glomerular diseases. A thorough understanding of podocyte endocytosis may shed novel insights into its biological function in maintaining a functioning filter and offer potential targeted therapeutic strategies for proteinuric glomerular diseases.
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Affiliation(s)
| | | | - Shuta Ishibe
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, United States
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27
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Prichard KL, O'Brien NS, Murcia SR, Baker JR, McCluskey A. Role of Clathrin and Dynamin in Clathrin Mediated Endocytosis/Synaptic Vesicle Recycling and Implications in Neurological Diseases. Front Cell Neurosci 2022; 15:754110. [PMID: 35115907 PMCID: PMC8805674 DOI: 10.3389/fncel.2021.754110] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 12/10/2021] [Indexed: 12/17/2022] Open
Abstract
Endocytosis is a process essential to the health and well-being of cell. It is required for the internalisation and sorting of “cargo”—the macromolecules, proteins, receptors and lipids of cell signalling. Clathrin mediated endocytosis (CME) is one of the key processes required for cellular well-being and signalling pathway activation. CME is key role to the recycling of synaptic vesicles [synaptic vesicle recycling (SVR)] in the brain, it is pivotal to signalling across synapses enabling intracellular communication in the sensory and nervous systems. In this review we provide an overview of the general process of CME with a particular focus on two key proteins: clathrin and dynamin that have a central role to play in ensuing successful completion of CME. We examine these two proteins as they are the two endocytotic proteins for which small molecule inhibitors, often of known mechanism of action, have been identified. Inhibition of CME offers the potential to develop therapeutic interventions into conditions involving defects in CME. This review will discuss the roles and the current scope of inhibitors of clathrin and dynamin, providing an insight into how further developments could affect neurological disease treatments.
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28
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Abstract
CD46 is a receptor for human herpesvirus 6A (HHV-6A) and is in some cells also important for infection with HHV-6B. CD46 has several isoforms of which the most commonly expressed can be distinguished by expression of a BC domain or a C domain in a serine-threonine-proline rich (STP) extracellular region. Using a SupT1 CD46 CRISPR-Cas9 knockout model system reconstituted with specific CD46 isoforms, we demonstrated that HHV-6A infection was more efficient when BC-isoforms were expressed as opposed to C-isoforms, measured by higher levels of intracellular viral transcripts and recovery of more progeny virus. Although the B domain contains several O-glycosylations, mutations of Ser and Thr residues did not prevent infection with HHV-6A. The HHV-6A infection was blocked by inhibitors of clathrin-mediated endocytosis. In contrast, infection with HHV-6B was preferentially promoted by C-isoforms mediating fusion-from-without, and this infection was less affected by inhibitors of clathrin-mediated endocytosis. Taken together, HHV-6A preferred BC isoforms, mediating endocytosis, whereas HHV-6B preferred C isoforms, mediating fusion-from-without. This demonstrates that the STP region of CD46 is important for regulating the mode of infection in SupT1 cells and suggests an epigenetic regulation of the host susceptibility to HHV-6A and HHV-6B infection. Importance CD46 is the receptor used by human herpesvirus 6A (HHV-6A) during infection of T cells, but it is also involved in infection of certain T cells by HHV-6B. The gene for CD46 allows expression of several variants of CD46, known as isoforms, but whether the isoforms matter for infection of T cells is unknown. We used a genetic approach to delete CD46 from T cells and reconstituted them with separate isoforms to study these individually. We expressed the isoforms known as BC and C, which are distinguished by the potential inclusion of a B domain in the CD46 molecule. We demonstrate that HHV-6A prefers the BC isoform to infect T cells, and this occurs predominantly by clathrin-mediated endocytosis. In contrast, HHV-6B prefers the C isoform and infects predominantly by fusion-from-without. Thus, CD46 isoforms may affect susceptibility of T cells to infection with HHV-6A and HHV-6B.
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29
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Contreras GF, Saavedra J, Navarro-Quezada N, Mellado G, Gonzalez C, Neely A. Direct inhibition of Ca V2.3 by Gem is dynamin dependent and does not require a direct alfa/beta interaction. Biochem Biophys Res Commun 2022; 586:107-113. [PMID: 34837834 DOI: 10.1016/j.bbrc.2021.11.052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/21/2021] [Accepted: 11/14/2021] [Indexed: 11/17/2022]
Abstract
The Rad, Rem, Rem2, and Gem/Kir (RGK) sub-family of small GTP-binding proteins are crucial in regulating high voltage-activated (HVA) calcium channels. RGK proteins inhibit calcium current by either promoting endocytosis or reducing channel activity. They all can associate directly with Ca2+ channel β subunit (CaVβ), and the binding between CaVα1/CaVβ appears essential for the endocytic promotion of CaV1.X, CaV2.1, and CaV2.2 channels. In this study, we investigated the inhibition of CaV2.3 channels by RGK proteins in the absence of CaVβ. To this end, Xenopus laevis oocytes expressing CaV2.3 channels devoid of auxiliary subunit were injected with purified Gem and Rem and found that only Gem had an effect. Ca currents and charge movements were reduced by injection of Gem, pointing to a reduction in the number of channels in the plasma membrane. Since this reduction was ablated by co-expression of the dominant-negative mutant of dynamin K44A, enhanced endocytosis appears to mediate this reduction in the number of channels. Thus, Gem inhibition of CaV2.3 channels would be the only example of a CaVβ independent promotion of dynamin-dependent endocytosis.
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Affiliation(s)
- Gustavo F Contreras
- Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaiso, Chile; Centro Interdisciplinario de Neurociencias Valparaíso, Chile
| | - Jonathan Saavedra
- Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaiso, Chile; Centro Interdisciplinario de Neurociencias Valparaíso, Chile; Doctorado en Ciencias Mención Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Nieves Navarro-Quezada
- Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaiso, Chile; Centro Interdisciplinario de Neurociencias Valparaíso, Chile
| | - Guido Mellado
- Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaiso, Chile; Centro Interdisciplinario de Neurociencias Valparaíso, Chile; Doctorado en Ciencias Mención Biofisica y Biología Computacional, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Carlos Gonzalez
- Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaiso, Chile; Centro Interdisciplinario de Neurociencias Valparaíso, Chile; Cardiovascular Research, Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA
| | - Alan Neely
- Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaiso, Chile
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30
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Russell CC, Prichard KL, O'Brien NS, McCluskey A, Robinson PJ, Baker JR. Synthesis of Phthaladyn-29 and Naphthalimide-10, GTP Site Directed Dynamin GTPase Inhibitors. Methods Mol Biol 2022; 2417:239-258. [PMID: 35099804 DOI: 10.1007/978-1-0716-1916-2_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Herein we describe the detailed synthesis of the dynamin inhibitors Phthaladyn-29 and Napthaladyn-10, and their chemical scaffold matched partner inactive compounds. Combined with the assay data provided, this allows the interrogation of dynamin in vitro and potentially in vivo.
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Affiliation(s)
- Cecilia C Russell
- Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Kate L Prichard
- Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Nicholas S O'Brien
- Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Adam McCluskey
- Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
| | - Phillip J Robinson
- Cell Signaling Unit, Children's Medical Research Institute, The University of Sydney, Sydney, NSW, Australia
| | - Jennifer R Baker
- Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia.
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Keum S, Yang SJ, Park E, Kang T, Choi JH, Jeong J, Hwang YE, Kim JW, Park D, Rhee S. Beta-Pix-dynamin 2 complex promotes colorectal cancer progression by facilitating membrane dynamics. Cell Oncol (Dordr) 2021; 44:1287-1305. [PMID: 34582006 PMCID: PMC8648671 DOI: 10.1007/s13402-021-00637-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 09/14/2021] [Indexed: 12/24/2022] Open
Abstract
PURPOSE Spatiotemporal regulation of cell membrane dynamics is a major process that promotes cancer cell invasion by acting as a driving force for cell migration. Beta-Pix (βPix), a guanine nucleotide exchange factor for Rac1, has been reported to be involved in actin-mediated cellular processes, such as cell migration, by interacting with various proteins. As yet, however, the molecular mechanisms underlying βPix-mediated cancer cell invasion remain unclear. METHODS The clinical significance of βPix was analyzed in patients with colorectal cancer (CRC) using public clinical databases. Pull-down and immunoprecipitation assays were employed to identify novel binding partners for βPix. Additionally, various cell biological assays including immunocytochemistry and time-lapse video microscopy were performed to assess the effects of βPix on CRC progression. A βPix-SH3 antibody delivery system was used to determine the effects of the βPix-Dyn2 complex in CRC cells. RESULTS We found that the Src homology 3 (SH3) domain of βPix interacts with the proline-rich domain of Dynamin 2 (Dyn2), a large GTPase. The βPix-Dyn2 interaction promoted lamellipodia formation, along with plasma membrane localization of membrane-type 1 matrix metalloproteinase (MT1-MMP). Furthermore, we found that Src kinase-mediated phosphorylation of the tyrosine residue at position 442 of βPix enhanced βPix-Dyn2 complex formation. Disruption of the βPix-Dyn2 complex by βPix-SH3 antibodies targeting intracellular βPix inhibited CRC cell invasion. CONCLUSIONS Our data indicate that spatiotemporal regulation of the Src-βPix-Dyn2 axis is crucial for CRC cell invasion by promoting membrane dynamics and MT1-MMP recruitment into the leading edge. The development of inhibitors that disrupt the βPix-Dyn2 complex may be a useful therapeutic strategy for CRC.
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Affiliation(s)
- Seula Keum
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Soo Jung Yang
- Translational Research Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, 98101, USA
| | - Esther Park
- School of Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - TaeIn Kang
- School of Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jee-Hye Choi
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Jangho Jeong
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Ye Eun Hwang
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Jung-Woong Kim
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Dongeun Park
- School of Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sangmyung Rhee
- Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea.
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Fujise K, Okubo M, Abe T, Yamada H, Takei K, Nishino I, Takeda T, Noguchi S. Imaging-based evaluation of pathogenicity by novel DNM2 variants associated with centronuclear myopathy. Hum Mutat 2021; 43:169-179. [PMID: 34837441 DOI: 10.1002/humu.24307] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 11/04/2021] [Accepted: 11/06/2021] [Indexed: 11/11/2022]
Abstract
A centronuclear myopathy (CNM) is a group of inherited congenital diseases showing clinically progressive muscle weakness associated with the presence of centralized myonuclei, diagnosed by genetic testing and muscle biopsy. The gene encoding dynamin 2, DNM2, has been identified as a causative gene for an autosomal dominant form of CNM. However, the information of a DNM2 variant alone is not always sufficient to gain a definitive diagnosis as the pathogenicity of many gene variants is currently unknown. In this study, we identified five novel DNM2 variants in our cohort. To establish the pathogenicity of these variants without using clinicopathological information, we used a simple in cellulo imaging-based assay for T-tubule-like structures to provide quantitative data that enable objective determination of pathogenicity by novel DNM2 variants. With this assay, we demonstrated that the phenotypes induced by mutant dynamin 2 in cellulo are well correlated with biochemical gain-of-function features of mutant dynamin 2 as well as the clinicopathological phenotypes of each patient. Our approach of combining an in cellulo assay with clinical information of the patients also explains the course of a disease progression by the pathogenesis of each variant in DNM2-associated CNM.
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Affiliation(s)
- Kenshiro Fujise
- Department of Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Mariko Okubo
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, Japan.,Department of Pediatrics, The University of Tokyo, Tokyo, Japan
| | - Tadashi Abe
- Department of Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hiroshi Yamada
- Department of Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Kohji Takei
- Department of Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, Japan
| | - Tetsuya Takeda
- Department of Biochemistry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Satoru Noguchi
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, Japan
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Lukácsi S, Farkas Z, Saskői É, Bajtay Z, Takács-Vellai K. Conserved and Distinct Elements of Phagocytosis in Human and C. elegans. Int J Mol Sci 2021; 22:ijms22168934. [PMID: 34445642 PMCID: PMC8396242 DOI: 10.3390/ijms22168934] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/12/2021] [Accepted: 08/17/2021] [Indexed: 12/12/2022] Open
Abstract
Endocytosis provides the cellular nutrition and homeostasis of organisms, but pathogens often take advantage of this entry point to infect host cells. This is counteracted by phagocytosis that plays a key role in the protection against invading microbes both during the initial engulfment of pathogens and in the clearance of infected cells. Phagocytic cells balance two vital functions: preventing the accumulation of cell corpses to avoid pathological inflammation and autoimmunity, whilst maintaining host defence. In this review, we compare elements of phagocytosis in mammals and the nematode Caenorhabditis elegans. Initial recognition of infection requires different mechanisms. In mammals, pattern recognition receptors bind pathogens directly, whereas activation of the innate immune response in the nematode rather relies on the detection of cellular damage. In contrast, molecules involved in efferocytosis—the engulfment and elimination of dying cells and cell debris—are highly conserved between the two species. Therefore, C. elegans is a powerful model to research mechanisms of the phagocytic machinery. Finally, we show that both mammalian and worm studies help to understand how the two phagocytic functions are interconnected: emerging data suggest the activation of innate immunity as a consequence of defective apoptotic cell clearance.
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Affiliation(s)
- Szilvia Lukácsi
- MTA-ELTE Immunology Research Group, Eötvös Loránd Research Network (ELKH), Eötvös Loránd University, Pázmány Péter s. 1/C, 1117 Budapest, Hungary; (S.L.); (Z.B.)
| | - Zsolt Farkas
- Department of Biological Anthropology, Eötvös Loránd University, Pázmány Péter s. 1/C, 1117 Budapest, Hungary; (Z.F.); (É.S.)
| | - Éva Saskői
- Department of Biological Anthropology, Eötvös Loránd University, Pázmány Péter s. 1/C, 1117 Budapest, Hungary; (Z.F.); (É.S.)
| | - Zsuzsa Bajtay
- MTA-ELTE Immunology Research Group, Eötvös Loránd Research Network (ELKH), Eötvös Loránd University, Pázmány Péter s. 1/C, 1117 Budapest, Hungary; (S.L.); (Z.B.)
- Department of Immunology, Eötvös Loránd University, Pázmány Péter s. 1/C, 1117 Budapest, Hungary
| | - Krisztina Takács-Vellai
- Department of Biological Anthropology, Eötvös Loránd University, Pázmány Péter s. 1/C, 1117 Budapest, Hungary; (Z.F.); (É.S.)
- Correspondence:
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Yigit G, Sheffer R, Daana M, Li Y, Kaygusuz E, Mor-Shakad H, Altmüller J, Nürnberg P, Douiev L, Kaulfuss S, Burfeind P, Wollnik B, Brockmann K. Loss-of-function variants in DNM1 cause a specific form of developmental and epileptic encephalopathy only in biallelic state. J Med Genet 2021; 59:549-553. [PMID: 34172529 PMCID: PMC9132866 DOI: 10.1136/jmedgenet-2021-107769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/08/2021] [Indexed: 11/23/2022]
Abstract
Background Developmental and epileptic encephalopathies (DEEs) represent a group of severe neurological disorders characterised by an onset of refractory seizures during infancy or early childhood accompanied by psychomotor developmental delay or regression. DEEs are genetically heterogeneous with, to date, more than 80 different genetic subtypes including DEE31 caused by heterozygous missense variants in DNM1. Methods We performed a detailed clinical characterisation of two unrelated patients with DEE and used whole-exome sequencing to identify causative variants in these individuals. The identified variants were tested for cosegregation in the respective families. Results We excluded pathogenic variants in known, DEE-associated genes. We identified homozygous nonsense variants, c.97C>T; p.(Gln33*) in family 1 and c.850C>T; p.(Gln284*) in family 2, in the DNM1 gene, indicating that biallelic, loss-of-function pathogenic variants in DNM1 cause DEE. Conclusion Our finding that homozygous, loss-of-function variants in DNM1 cause DEE expands the spectrum of pathogenic variants in DNM1. All parents who were heterozygous carriers of the identified loss-of-function variants were healthy and did not show any clinical symptoms, indicating that the type of mutation in DNM1 determines the pattern of inheritance.
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Affiliation(s)
- Gökhan Yigit
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Ruth Sheffer
- Department of Human Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Muhannad Daana
- Child Development Institute, Clalit Health Services, Tel Aviv, Israel
| | - Yun Li
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Emrah Kaygusuz
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany.,Molecular Biology and Genetics, Bilecik Şeyh Edebali University, Bilecik, Turkey
| | - Hagar Mor-Shakad
- Department of Human Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Janine Altmüller
- Cologne Center for Genomics (CCG), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Peter Nürnberg
- Cologne Center for Genomics (CCG), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Liza Douiev
- Department of Human Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Silke Kaulfuss
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Peter Burfeind
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany
| | - Bernd Wollnik
- Institute of Human Genetics, University Medical Center Göttingen, Gottingen, Germany .,Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Gottingen, Gottingen, Germany
| | - Knut Brockmann
- Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders, University Medical Center Göttingen, Gottingen, Germany
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Motta M, Consentino MC, Fontana A, Sciuto L, Falsaperla R, Praticò ER, Salafia S, Zanghì A, Praticò AD. DNM1 Gene and Its Related Epileptic Phenotypes. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1727258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractThe phenotypic variety associated to mutations in dynamin 1 (DNM1), codifying the presynaptic protein DNM1 has been increasingly reported, mainly related to encephalopathy with intractable epilepsy; currently, it is known the phenotype related to DNM1 gene mutations is relatively homogeneous with developmental delay, hypotonia, and epilepsy characterized by infantile spasms and possible progression to Lennox-Gastaut syndrome. By examining all the papers published until 2020 (18 articles), we compared data from 30 patients (extrapolated from 5 papers) with DNM1 mutations, identifying 26 patients with de novo mutations in DNM1. Nine patients (33.3%) reported the recurrent mutation p.Arg237Trp. A usual phenotype observed comprises severe to deep developmental delay and muscular hypotonia in all patients with epilepsy beginning with infantile spasms, which often evolved into Lennox-Gastaut syndrome. Data about GTPase or central domains mutations, and existing structural modeling and functional suggest a dominant negative effect on DMN1 function. Generally genetic epilepsies consist of a wide spectrum of clinical features, unlike that, DNM1-related CNS impairment phenotype is quite uniform. In up to one third of patients it has been found variant p.Arg237Trp, which is one of the most frequent variant detected in epileptic encephalopathies. The understanding of DNM1 function opens up the chance that this gene would become a new therapeutic target for epilepsies.
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Affiliation(s)
- Milena Motta
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Maria Chiara Consentino
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Alessandra Fontana
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Laura Sciuto
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Raffaele Falsaperla
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
- Unit of Neonatal Intensive Care and Neonatology, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
| | | | | | - Antonio Zanghì
- Department of Medical and Surgical Sciences and Advanced Technology “G.F. Ingrassia,” University of Catania, Catania, Italy
| | - Andrea D. Praticò
- Department of Clinical and Experimental Medicine, Unit of Rare Diseases of the Nervous System in Childhood, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
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36
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Zou L, Tian Y, Zhang Z. Dysfunction of Synaptic Vesicle Endocytosis in Parkinson's Disease. Front Integr Neurosci 2021; 15:619160. [PMID: 34093144 PMCID: PMC8172812 DOI: 10.3389/fnint.2021.619160] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 04/28/2021] [Indexed: 11/25/2022] Open
Abstract
Parkinson’s disease (PD) is the second most common neurodegenerative disorder after Alzheimer’s disease. It is a chronic and progressive disorder estimated to affect at least 4 million people worldwide. Although the etiology of PD remains unclear, it has been found that the dysfunction of synaptic vesicle endocytosis (SVE) in neural terminal happens before the loss of dopaminergic neurons. Recently, accumulating evidence reveals that the PD-linked synaptic genes, including DNAJC6, SYNJ1, and SH3GL2, significantly contribute to the disruptions of SVE, which is vital for the pathogenesis of PD. In addition, the proteins encoded by other PD-associated genes such as SNCA, LRRK2, PRKN, and DJ-1 also play key roles in the regulation of SVE. Here we present the facts about SVE-related genes and discussed their potential relevance to the pathogenesis of PD.
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Affiliation(s)
- Li Zou
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Ye Tian
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zhentao Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
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37
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O'Donnell JP, Kelly CM, Sondermann H. Nucleotide-Dependent Dimerization and Conformational Switching of Atlastin. Methods Mol Biol 2021; 2159:93-113. [PMID: 32529366 DOI: 10.1007/978-1-0716-0676-6_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A common feature of dynamin-related proteins (DRPs) is their use of guanosine triphosphate (GTP) to control protein dynamics. In the case of the endoplasmic- reticulum- (ER)-resident membrane protein atlastin (ATL), GTP binding and hydrolysis result in membrane fusion of ER tubules and the generation of a branched ER network. In this chapter, we describe two independent methods for dissecting the mechanism underlying nucleotide-dependent quaternary structure and conformational changes of ATL, focusing on size-exclusion chromatography coupled with multi-angle light scattering (SEC-MALS) and Förster resonance energy transfer (FRET), respectively. The high temporal resolution of the FRET-based assays enables the ordering of the molecular events identified in structural and equilibrium-based SEC-MALS studies. In combination, these complementary methods report on the oligomeric states of a system at equilibrium and timing of key steps along the enzyme's catalytic cycle. These methods are broadly applicable to proteins that undergo ligand-induced dimerization and/or conformational changes.
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Affiliation(s)
- John P O'Donnell
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
- Cell Biology Division, MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Carolyn M Kelly
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Holger Sondermann
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
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Fujise K, Okubo M, Abe T, Yamada H, Nishino I, Noguchi S, Takei K, Takeda T. Mutant BIN1-Dynamin 2 complexes dysregulate membrane remodeling in the pathogenesis of centronuclear myopathy. J Biol Chem 2021; 296:100077. [PMID: 33187981 PMCID: PMC7949082 DOI: 10.1074/jbc.ra120.015184] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 11/10/2020] [Accepted: 11/13/2020] [Indexed: 11/08/2022] Open
Abstract
Membrane remodeling is required for dynamic cellular processes such as cell division, polarization, and motility. BAR domain proteins and dynamins are key molecules in membrane remodeling that work together for membrane deformation and fission. In striated muscles, sarcolemmal invaginations termed T-tubules are required for excitation-contraction coupling. BIN1 and DNM2, which encode a BAR domain protein BIN1 and dynamin 2, respectively, have been reported to be causative genes of centronuclear myopathy (CNM), a hereditary degenerative disease of skeletal muscle, and deformation of T-tubules is often observed in the CNM patients. However, it remains unclear how BIN1 and dynamin 2 are implicated in T-tubule biogenesis and how mutations in these molecules cause CNM to develop. Here, using an in cellulo reconstitution assay, we demonstrate that dynamin 2 is required for stabilization of membranous structures equivalent to T-tubules. GTPase activity of wild-type dynamin 2 is suppressed through interaction with BIN1, whereas that of the disease-associated mutant dynamin 2 remains active due to lack of the BIN1-mediated regulation, thus causing aberrant membrane remodeling. Finally, we show that in cellulo aberrant membrane remodeling by mutant dynamin 2 variants is correlated with their enhanced membrane fission activities, and the results can explain severity of the symptoms in patients. Thus, this study provides molecular insights into dysregulated membrane remodeling triggering the pathogenesis of DNM2-related CNM.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Adaptor Proteins, Signal Transducing/physiology
- Animals
- Blotting, Western
- Dynamin II/genetics
- Dynamin II/metabolism
- HEK293 Cells
- Humans
- Immunoprecipitation
- Microscopy, Fluorescence
- Muscle, Skeletal/metabolism
- Myopathies, Structural, Congenital/genetics
- Myopathies, Structural, Congenital/metabolism
- Nanotubes/chemistry
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Tumor Suppressor Proteins/genetics
- Tumor Suppressor Proteins/metabolism
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Affiliation(s)
- Kenshiro Fujise
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Mariko Okubo
- National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, Japan; Department of Pediatrics, The University of Tokyo, Tokyo, Japan
| | - Tadashi Abe
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Hiroshi Yamada
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Ichizo Nishino
- National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, Japan
| | - Satoru Noguchi
- National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, Japan
| | - Kohji Takei
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | - Tetsuya Takeda
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
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Tu C, Du Z, Zhang H, Feng Y, Qi Y, Zheng Y, Liu J, Wang J. Endocytic pathway inhibition attenuates extracellular vesicle-induced reduction of chemosensitivity to bortezomib in multiple myeloma cells. Am J Cancer Res 2021; 11:2364-2380. [PMID: 33500730 PMCID: PMC7797667 DOI: 10.7150/thno.47996] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 11/18/2020] [Indexed: 12/16/2022] Open
Abstract
Extracellular vesicles (EVs), including exosomes and microvesicles, derived from bone marrow stromal cells (BMSCs) have been demonstrated as key factors in the progression and drug resistance of multiple myeloma (MM). EV uptake involves a variety of mechanisms which largely depend on the vesicle origin and recipient cell type. The aim of the present study was to identify the mechanisms involved in the uptake of BMSC-derived small EVs (sEVs) by MM cells, and to evaluate the anti-MM effect of targeting this process. Methods: Human BMSC-derived sEVs were identified by transmission electron microscopy, nanoparticle tracking analysis, and western blot. The effects of chemical inhibitors and shRNA-mediated knockdown of endocytosis-associated genes on sEV uptake and cell apoptosis were analyzed by flow cytometry. The anti-MM effect of blocking sEV uptake was evaluated in vitro and in a xenograft MM mouse model. Results: sEVs derived from BMSC were taken up by MM cells in a time- and dose-dependent manner, and subsequently promoted MM cell cycling and reduced their chemosensitivity to bortezomib. Chemical endocytosis inhibitors targeting heparin sulphate proteoglycans, actin, tyrosine kinase, dynamin-2, sodium/proton exchangers, or phosphoinositide 3-kinases significantly reduced MM cell internalization of BMSC-derived sEVs. Moreover, shRNA-mediated knockdown of endocytosis-associated proteins, including caveolin-1, flotillin-1, clathrin heavy chain, and dynamin-2 in MM cells suppressed sEV uptake. Furthermore, an endocytosis inhibitor targeting dynamin-2 preferentially suppressed the uptake of sEV by primary MM cells ex vivo and enhanced the anti-MM effects of bortezomib in vitro and in a mouse model. Conclusion: Clathrin- and caveolin-dependent endocytosis and macropinocytosis are the predominant routes of sEV-mediated communication between BMSCs and MM cells, and inhibiting endocytosis attenuates sEV-induced reduction of chemosensitivity to bortezomib, and thus enhances its anti-MM properties.
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40
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Mayberry CL, Maginnis MS. Taking the Scenic Route: Polyomaviruses Utilize Multiple Pathways to Reach the Same Destination. Viruses 2020; 12:v12101168. [PMID: 33076363 PMCID: PMC7602598 DOI: 10.3390/v12101168] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 01/02/2023] Open
Abstract
Members of the Polyomaviridae family differ in their host range, pathogenesis, and disease severity. To date, some of the most studied polyomaviruses include human JC, BK, and Merkel cell polyomavirus and non-human subspecies murine and simian virus 40 (SV40) polyomavirus. Although dichotomies in host range and pathogenesis exist, overlapping features of the infectious cycle illuminate the similarities within this virus family. Of particular interest to human health, JC, BK, and Merkel cell polyomavirus have all been linked to critical, often fatal, illnesses, emphasizing the importance of understanding the underlying viral infections that result in the onset of these diseases. As there are significant overlaps in the capacity of polyomaviruses to cause disease in their respective hosts, recent advancements in characterizing the infectious life cycle of non-human murine and SV40 polyomaviruses are key to understanding diseases caused by their human counterparts. This review focuses on the molecular mechanisms by which different polyomaviruses hijack cellular processes to attach to host cells, internalize, traffic within the cytoplasm, and disassemble within the endoplasmic reticulum (ER), prior to delivery to the nucleus for viral replication. Unraveling the fundamental processes that facilitate polyomavirus infection provides deeper insight into the conserved mechanisms of the infectious process shared within this virus family, while also highlighting critical unique viral features.
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Affiliation(s)
- Colleen L. Mayberry
- Department of Molecular and Biomedical Sciences, The University of Maine, Orono, ME 04469, USA;
| | - Melissa S. Maginnis
- Department of Molecular and Biomedical Sciences, The University of Maine, Orono, ME 04469, USA;
- Graduate School in Biomedical Sciences and Engineering, The University of Maine, Orono, ME 04469, USA
- Correspondence:
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Aimiuwu OV, Fowler AM, Sah M, Teoh JJ, Kanber A, Pyne NK, Petri S, Rosenthal-Weiss C, Yang M, Harper SQ, Frankel WN. RNAi-Based Gene Therapy Rescues Developmental and Epileptic Encephalopathy in a Genetic Mouse Model. Mol Ther 2020; 28:1706-1716. [PMID: 32353324 PMCID: PMC7335739 DOI: 10.1016/j.ymthe.2020.04.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/19/2020] [Accepted: 04/08/2020] [Indexed: 01/23/2023] Open
Abstract
Developmental and epileptic encephalopathy (DEE) associated with de novo variants in the gene encoding dynamin-1 (DNM1) is a severe debilitating disease with no pharmacological remedy. Like most genetic DEEs, the majority of DNM1 patients suffer from therapy-resistant seizures and comorbidities such as intellectual disability, developmental delay, and hypotonia. We tested RNAi gene therapy in the Dnm1 fitful mouse model of DEE using a Dnm1-targeted therapeutic microRNA delivered by a self-complementary adeno-associated virus vector. Untreated or control-injected fitful mice have growth delay, severe ataxia, and lethal tonic-clonic seizures by 3 weeks of age. These major impairments are mitigated following a single treatment in newborn mice, along with key underlying cellular features including gliosis, cell death, and aberrant neuronal metabolic activity typically associated with recurrent seizures. Our results underscore the potential for RNAi gene therapy to treat DNM1 disease and other genetic DEEs where treatment would require inhibition of the pathogenic gene product.
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Affiliation(s)
- Osasumwen V Aimiuwu
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Allison M Fowler
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Megha Sah
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jia Jie Teoh
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Ayla Kanber
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Nettie K Pyne
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Sabrina Petri
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Chana Rosenthal-Weiss
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Mu Yang
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Scott Q Harper
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43205, USA
| | - Wayne N Frankel
- Institute for Genomic Medicine and Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA.
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42
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Walpole GFW, Grinstein S. Endocytosis and the internalization of pathogenic organisms: focus on phosphoinositides. F1000Res 2020; 9. [PMID: 32494357 PMCID: PMC7233180 DOI: 10.12688/f1000research.22393.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/07/2020] [Indexed: 12/18/2022] Open
Abstract
Despite their comparatively low abundance in biological membranes, phosphoinositides are key to the regulation of a diverse array of signaling pathways and direct membrane traffic. The role of phosphoinositides in the initiation and progression of endocytic pathways has been studied in considerable depth. Recent advances have revealed that distinct phosphoinositide species feature prominently in clathrin-dependent and -independent endocytosis as well as in phagocytosis and macropinocytosis. Moreover, a variety of intracellular and cell-associated pathogens have developed strategies to commandeer host cell phosphoinositide metabolism to gain entry and/or metabolic advantage, thereby promoting their survival and proliferation. Here, we briefly survey the current knowledge on the involvement of phosphoinositides in endocytosis, phagocytosis, and macropinocytosis and highlight several examples of molecular mimicry employed by pathogens to either “hitch a ride” on endocytic pathways endogenous to the host or create an entry path of their own.
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Affiliation(s)
- Glenn F W Walpole
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Sergio Grinstein
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
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43
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Zhang D, Zhang Y, Ma J, Zhu C, Niu T, Chen W, Pang X, Zhai Y, Sun F. Cryo-EM structures of S-OPA1 reveal its interactions with membrane and changes upon nucleotide binding. eLife 2020; 9:50294. [PMID: 32228866 PMCID: PMC7156267 DOI: 10.7554/elife.50294] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 03/30/2020] [Indexed: 02/05/2023] Open
Abstract
Mammalian mitochondrial inner membrane fusion is mediated by optic atrophy 1 (OPA1). Under physiological conditions, OPA1 undergoes proteolytic processing to form a membrane-anchored long isoform (L-OPA1) and a soluble short isoform (S-OPA1). A combination of L-OPA1 and S-OPA1 is essential for efficient membrane fusion; however, the relevant mechanism is not well understood. In this study, we investigate the cryo-electron microscopic structures of S-OPA1–coated liposomes in nucleotide-free and GTPγS-bound states. S-OPA1 exhibits a general dynamin-like structure and can assemble onto membranes in a helical array with a dimer building block. We reveal that hydrophobic residues in its extended membrane-binding domain are critical for its tubulation activity. The binding of GTPγS triggers a conformational change and results in a rearrangement of the helical lattice and tube expansion similar to that of S-Mgm1. These observations indicate that S-OPA1 adopts a dynamin-like power stroke membrane remodeling mechanism during mitochondrial inner membrane fusion.
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Affiliation(s)
- Danyang Zhang
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yan Zhang
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jun Ma
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Chunmei Zhu
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Tongxin Niu
- Center for Biological Imaging, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Wenbo Chen
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoyun Pang
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yujia Zhai
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Fei Sun
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,Center for Biological Imaging, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
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44
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Polymer-like Model to Study the Dynamics of Dynamin Filaments on Deformable Membrane Tubes. Biophys J 2019; 117:1870-1891. [PMID: 31672269 DOI: 10.1016/j.bpj.2019.09.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/08/2019] [Accepted: 09/24/2019] [Indexed: 01/30/2023] Open
Abstract
Peripheral membrane proteins with intrinsic curvature can act both as sensors of membrane curvature and shape modulators of the underlying membranes. A well-studied example of such proteins is the mechanochemical GTPase dynamin, which assembles into helical filaments around membrane tubes and catalyzes their scission in a GTPase-dependent manner. It is known that the dynamin coat alone, without GTP, can constrict membrane tubes to radii of ∼10 nm, indicating that the intrinsic shape and elasticity of dynamin filaments should play an important role in membrane remodeling. However, molecular and dynamic understanding of the process is lacking. Here, we develop a dynamical polymer-chain model for a helical elastic filament bound on a deformable membrane tube of conserved mass, accounting for thermal fluctuations in the filament and lipid flows in the membrane. The model is based on the locally cylindrical helix approximation for dynamin. We obtain the elastic parameters of the dynamin filament by molecular dynamics simulations of its tetrameric building block and also from coarse-grained structure-based simulations of a 17-dimer filament. The results show that the stiffness of dynamin is comparable to that of the membrane. We determine equilibrium shapes of the filament and the membrane and find that mostly the pitch of the filament, not its radius, is sensitive to variations in membrane tension and stiffness. The close correspondence between experimental estimates of the inner tube radius and those predicted by the model suggests that dynamin's "stalk" region is responsible for its GTP-independent membrane-shaping ability. The model paves the way for future mesoscopic modeling of dynamin with explicit motor function.
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45
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Ford MGJ, Chappie JS. The structural biology of the dynamin-related proteins: New insights into a diverse, multitalented family. Traffic 2019; 20:717-740. [PMID: 31298797 DOI: 10.1111/tra.12676] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 07/10/2019] [Accepted: 07/10/2019] [Indexed: 12/13/2022]
Abstract
Dynamin-related proteins are multidomain, mechanochemical GTPases that self-assemble and orchestrate a wide array of cellular processes. Over the past decade, structural insights from X-ray crystallography and cryo-electron microscopy have reshaped our mechanistic understanding of these proteins. Here, we provide a historical perspective on these advances that highlights the structural attributes of different dynamin family members and explores how these characteristics affect GTP hydrolysis, conformational coupling and oligomerization. We also discuss a number of lingering challenges remaining in the field that suggest future directions of study.
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Affiliation(s)
- Marijn G J Ford
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Joshua S Chappie
- Department of Molecular Medicine, Cornell University, Ithaca, New York
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46
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Kalia R, Frost A. Open and cut: allosteric motion and membrane fission by dynamin superfamily proteins. Mol Biol Cell 2019; 30:2097-2104. [PMID: 31365329 PMCID: PMC6743466 DOI: 10.1091/mbc.e16-10-0709] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/07/2019] [Accepted: 06/18/2019] [Indexed: 12/20/2022] Open
Abstract
Cells have evolved diverse protein-based machinery to reshape, cut, or fuse their membrane-delimited compartments. Dynamin superfamily proteins are principal components of this machinery and use their ability to hydrolyze GTP and to polymerize into helices and rings to achieve these goals. Nucleotide-binding, hydrolysis, and exchange reactions drive significant conformational changes across the dynamin family, and these changes alter the shape and stability of supramolecular dynamin oligomers, as well as the ability of dynamins to bind receptors and membranes. Mutations that interfere with the conformational repertoire of these enzymes, and hence with membrane fission, exist in several inherited human diseases. Here, we discuss insights from new x-ray crystal structures and cryo-EM reconstructions that have enabled us to infer some of the allosteric dynamics for these proteins. Together, these studies help us to understand how dynamins perform mechanical work, as well as how specific mutants of dynamin family proteins exhibit pathogenic properties.
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Affiliation(s)
- Raghav Kalia
- Department of Physiology, University of California, San Francisco, San Francisco, CA 94158
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84132
| | - Adam Frost
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84132
- Chan-Zuckerberg Biohub, San Francisco, CA 94158
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47
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The late stage of COPI vesicle fission requires shorter forms of phosphatidic acid and diacylglycerol. Nat Commun 2019; 10:3409. [PMID: 31363100 PMCID: PMC6667475 DOI: 10.1038/s41467-019-11324-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/21/2019] [Indexed: 12/19/2022] Open
Abstract
Studies on vesicle formation by the Coat Protein I (COPI) complex have contributed to a basic understanding of how vesicular transport is initiated. Phosphatidic acid (PA) and diacylglycerol (DAG) have been found previously to be required for the fission stage of COPI vesicle formation. Here, we find that PA with varying lipid geometry can all promote early fission, but only PA with shortened acyl chains promotes late fission. Moreover, diacylglycerol (DAG) acts after PA in late fission, with this role of DAG also requiring shorter acyl chains. Further highlighting the importance of the short-chain lipid geometry for late fission, we find that shorter forms of PA and DAG promote the vesiculation ability of COPI fission factors. These findings advance a general understanding of how lipid geometry contributes to membrane deformation for vesicle fission, and also how proteins and lipids coordinate their actions in driving this process.
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48
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Abstract
Dynamin proteins assemble into characteristic helical structures around necks of clathrin-coated membrane buds. Hydrolysis of dynamin-bound GTP results in both fission of the membrane neck and partial disruption of the dynamin oligomer. Imaging by atomic force microscopy reveals that, on GTP hydrolysis, dynamin oligomers undergo a dynamic remodeling and lose their distinctive helical shape. While breakup of the dynamin helix is a critical stage in clathrin-mediated endocytosis, the mechanism for this remodeling of the oligomer has not been resolved. In this paper, we formulate an analytical, elasticity-based model for the reshaping and disassembly of the dynamin scaffold. We predict that the shape of the oligomer is modulated by the orientation of dynamin's pleckstrin homology (PH) domain relative to the underlying membrane. Our results indicate that tilt of the PH domain drives deformation and fragmentation of the oligomer, in agreement with experimental observations. This model motivated the introduction of the tilted helix: a curve that maintains a fixed angle between its normal and the normal of the embedding surface. Our findings highlight the importance of tilt as a key regulator of size and morphology of membrane-bound oligomers.
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49
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Guček A, Gandasi NR, Omar-Hmeadi M, Bakke M, Døskeland SO, Tengholm A, Barg S. Fusion pore regulation by cAMP/Epac2 controls cargo release during insulin exocytosis. eLife 2019; 8:41711. [PMID: 31099751 PMCID: PMC6557626 DOI: 10.7554/elife.41711] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 04/28/2019] [Indexed: 12/20/2022] Open
Abstract
Regulated exocytosis establishes a narrow fusion pore as initial aqueous connection to the extracellular space, through which small transmitter molecules such as ATP can exit. Co-release of polypeptides and hormones like insulin requires further expansion of the pore. There is evidence that pore expansion is regulated and can fail in diabetes and neurodegenerative disease. Here, we report that the cAMP-sensor Epac2 (Rap-GEF4) controls fusion pore behavior by acutely recruiting two pore-restricting proteins, amisyn and dynamin-1, to the exocytosis site in insulin-secreting beta-cells. cAMP elevation restricts and slows fusion pore expansion and peptide release, but not when Epac2 is inactivated pharmacologically or in Epac2-/- (Rapgef4-/-) mice. Consistently, overexpression of Epac2 impedes pore expansion. Widely used antidiabetic drugs (GLP-1 receptor agonists and sulfonylureas) activate this pathway and thereby paradoxically restrict hormone release. We conclude that Epac2/cAMP controls fusion pore expansion and thus the balance of hormone and transmitter release during insulin granule exocytosis. Insulin is the hormone that signals to the body to take up sugar from the blood. Specialized cells in the pancreas – known as β-cells – release insulin after a meal. Before that, insulin molecules are stored in tiny granules inside the β-cells; these granules must fuse with the cells’ surface membranes to release their contents. The first step in this process creates a narrow pore that allows small molecules, but not the larger insulin molecules, to seep out. The pore then widens to release the insulin. Since the small molecules are known to act locally in the pancreas, it is possible that this “molecular sieve” is biologically important. Yet it is not clear how the pore widens. One of the problems for people with type 2 diabetes is that they release less insulin into the bloodstream. Two kinds of drugs used to treat these patients work by stimulating β-cells to release their insulin. One way to achieve this is by raising the levels of a small molecule called cAMP, which is well known to help prepare insulin granules for release. The cAMP molecule also seems to slow the widening of the pore, and Gucek et al. have now investigated how this happens at a molecular level. By observing individual granules of human β-cells using a special microscope, Gucek et al. could watch how different drugs affect pore widening and content release. They also saw that cAMP activated a protein called Epac2, which then recruited two other proteins – amisyn and dynamin – to the small pores. These two proteins together then closed the pore, rather than expanding it to let insulin out. Type 2 diabetes patients sometimes have high levels of amisyn in their β-cells, which could explain why they do not release enough insulin. The microscopy experiments also revealed that two common anti-diabetic drugs activate Epac2 and prevent the pores from widening, thereby counteracting their positive effect on insulin release. The combined effect is likely a shift in the balance between insulin and the locally acting small molecules. These findings suggest that two common anti-diabetic drugs activate a common mechanism that may lead to unexpected outcomes, possibly even reducing how much insulin the β-cells can release. Future studies in mice and humans will have to investigate these effects in whole organisms.
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Affiliation(s)
- Alenka Guček
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Nikhil R Gandasi
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | | | - Marit Bakke
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | | | - Anders Tengholm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Sebastian Barg
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
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50
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JC Polyomavirus Entry by Clathrin-Mediated Endocytosis Is Driven by β-Arrestin. J Virol 2019; 93:JVI.01948-18. [PMID: 30700597 DOI: 10.1128/jvi.01948-18] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 01/22/2019] [Indexed: 01/09/2023] Open
Abstract
JC polyomavirus (JCPyV) establishes a persistent, lifelong, asymptomatic infection within the kidney of the majority of the human population. Under conditions of severe immunosuppression or immune modulation, JCPyV can reactivate in the central nervous system (CNS) and cause progressive multifocal leukoencephalopathy (PML), a fatal demyelinating disease. Initiation of infection is mediated through viral attachment to α2,6-sialic acid-containing lactoseries tetrasaccharide c (LSTc) on the surface of host cells. JCPyV internalization is dependent on serotonin 5-hydroxytryptamine subfamily 2 receptors (5-HT2Rs), and entry is thought to occur by clathrin-mediated endocytosis (CME). However, the JCPyV entry process and the cellular factors involved in viral internalization remain poorly understood. Treatment of cells with small-molecule chemical inhibitors and RNA interference of 5-HT2R endocytic machinery, including β-arrestin, clathrin, AP2, and dynamin, significantly reduced JCPyV infection. However, infectivity of the polyomavirus simian virus 40 (SV40) was not affected by CME-specific treatments. Inhibition of clathrin or β-arrestin specifically reduced JCPyV internalization but did not affect viral attachment. Furthermore, mutagenesis of a β-arrestin binding domain (Ala-Ser-Lys) within the intracellular C terminus of 5-HT2AR severely diminished internalization and infection, suggesting that β-arrestin interactions with 5-HT2AR are critical for JCPyV infection and entry. These conclusions illuminate key host factors that regulate clathrin-mediated endocytosis of JCPyV, which is necessary for viral internalization and productive infection.IMPORTANCE Viruses usurp cellular factors to invade host cells. Activation and utilization of these proteins upon initiation of viral infection are therefore required for productive infection and resultant viral disease. The majority of healthy individuals are asymptomatically infected by JC polyomavirus (JCPyV), but if the host immune system is compromised, JCPyV can cause progressive multifocal leukoencephalopathy (PML), a rare, fatal, demyelinating disease. Individuals infected with HIV or taking prolonged immunomodulatory therapies have a heightened risk for developing PML. The cellular proteins and pathways utilized by JCPyV to mediate viral entry are poorly understood. Our findings further characterize how JCPyV utilizes the clathrin-mediated endocytosis pathway to invade host cells. We have identified specific components of this pathway that are necessary for the viral entry process and infection. Collectively, the conclusions increase our understanding of JCPyV infection and pathogenesis and may contribute to the future development of novel therapeutic strategies for PML.
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