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Wang H, Tarsio M, Kane PM, Rubinstein JL. Structure of yeast RAVE bound to a partial V 1 complex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.18.604153. [PMID: 39071316 PMCID: PMC11275763 DOI: 10.1101/2024.07.18.604153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Vacuolar-type ATPases (V-ATPases) are membrane-embedded proton pumps that acidify intracellular compartments in almost all eukaryotic cells. Homologous with ATP synthases, these multi-subunit enzymes consist of a soluble catalytic V 1 subcomplex and a membrane-embedded proton-translocating V O subcomplex. The V 1 and V O subcomplexes can undergo reversible dissociation to regulate proton pumping, with reassociation of V 1 and V O requiring the protein complex known as RAVE (regulator of the A TPase of v acuoles and e ndosomes). In the yeast Saccharomyces cerevisiae , RAVE consists of subunits Rav1p, Rav2p, and Skp1p. We used electron cryomicroscopy (cryo-EM) to determine a structure of yeast RAVE bound to V 1 . In the structure, RAVE is a L-shaped complex with Rav2p pointing toward the membrane and Skp1p distant from both the membrane and V 1 . Only Rav1p interacts with V 1 , binding to a region of subunit A not found in the corresponding ATP synthase subunit. When bound to RAVE, V 1 is in a rotational state suitable for binding the free V O complex, but it is partially disrupted in the structure, missing five of its 16 subunits. Other than these missing subunits and the conformation of the inhibitory subunit H, the V 1 complex with RAVE appears poised for reassembly with V O .
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2
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Coupland CE, Karimi R, Bueler SA, Liang Y, Courbon GM, Di Trani JM, Wong CJ, Saghian R, Youn JY, Wang LY, Rubinstein JL. High-resolution electron cryomicroscopy of V-ATPase in native synaptic vesicles. Science 2024; 385:168-174. [PMID: 38900912 DOI: 10.1126/science.adp5577] [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: 04/01/2024] [Accepted: 05/16/2024] [Indexed: 06/22/2024]
Abstract
Intercellular communication in the nervous system occurs through the release of neurotransmitters into the synaptic cleft between neurons. In the presynaptic neuron, the proton pumping vesicular- or vacuolar-type ATPase (V-ATPase) powers neurotransmitter loading into synaptic vesicles (SVs), with the V1 complex dissociating from the membrane region of the enzyme before exocytosis. We isolated SVs from rat brain using SidK, a V-ATPase-binding bacterial effector protein. Single-particle electron cryomicroscopy allowed high-resolution structure determination of V-ATPase within the native SV membrane. In the structure, regularly spaced cholesterol molecules decorate the enzyme's rotor and the abundant SV protein synaptophysin binds the complex stoichiometrically. ATP hydrolysis during vesicle loading results in a loss of the V1 region of V-ATPase from the SV membrane, suggesting that loading is sufficient to induce dissociation of the enzyme.
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Affiliation(s)
- Claire E Coupland
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
| | - Ryan Karimi
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
- Department of Medical Biophysics, The University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Stephanie A Bueler
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
| | - Yingke Liang
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Gautier M Courbon
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
- Department of Medical Biophysics, The University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Justin M Di Trani
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
| | - Cassandra J Wong
- Lunenfeld-Tanenbaum Research Institute, Toronto, ON M5G 1X5, Canada
| | - Rayan Saghian
- Neuroscience and Mental Health Program, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
- Department of Physiology, The University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Ji-Young Youn
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
- Department of Molecular Genetics, The University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Lu-Yang Wang
- Neuroscience and Mental Health Program, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
- Department of Physiology, The University of Toronto, Toronto, ON M5S 1A8, Canada
| | - John L Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON M5G 1X1, Canada
- Department of Medical Biophysics, The University of Toronto, Toronto, ON M5G 1L7, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON M5S 1A8, Canada
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3
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Parra KJ. The merger of two major families of proteins that regulate cellular processes. Structure 2024; 32:851-853. [PMID: 38996510 DOI: 10.1016/j.str.2024.06.008] [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: 06/14/2024] [Revised: 06/14/2024] [Accepted: 06/16/2024] [Indexed: 07/14/2024]
Abstract
In this issue of Structure, Oot and Wilkens1 present new mechanistic insights to finally merge the function of V-ATPase and TLDc domain proteins. They show that TLDc proteins directly affect V-ATPase activity and assembly, expanding our understanding of how V-ATPase and TLDc proteins exert a plethora of biological functions.
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Affiliation(s)
- Karlett J Parra
- Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine, Albuquerque, NM, USA.
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4
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Oot RA, Wilkens S. Human V-ATPase function is positively and negatively regulated by TLDc proteins. Structure 2024; 32:989-1000.e6. [PMID: 38593795 PMCID: PMC11246223 DOI: 10.1016/j.str.2024.03.009] [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: 11/09/2023] [Revised: 02/23/2024] [Accepted: 03/13/2024] [Indexed: 04/11/2024]
Abstract
Proteins that contain a highly conserved TLDc domain (Tre2/Bub2/Cdc16 LysM domain catalytic) offer protection against oxidative stress and are widely implicated in neurological health and disease. How this family of proteins exerts their function, however, is poorly understood. We have recently found that the yeast TLDc protein, Oxr1p, inhibits the proton pumping vacuolar ATPase (V-ATPase) by inducing disassembly of the pump. While loss of TLDc protein function in mammals shares disease phenotypes with V-ATPase defects, whether TLDc proteins impact human V-ATPase activity directly is unclear. Here we examine the effects of five human TLDc proteins, TLDC2, NCOA7, OXR1, TBC1D24, and mEAK7 on the activity of the human V-ATPase. We find that while TLDC2, TBC1D24, and the TLDc domains of OXR1 and NCOA7 inhibit V-ATPase by inducing enzyme disassembly, mEAK7 activates the pump. The data thus shed new light both on mammalian TLDc protein function and V-ATPase regulation.
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Affiliation(s)
- Rebecca A Oot
- Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA.
| | - Stephan Wilkens
- Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
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Wang C, Jiang W, Leitz J, Yang K, Esquivies L, Wang X, Shen X, Held RG, Adams DJ, Basta T, Hampton L, Jian R, Jiang L, Stowell MHB, Baumeister W, Guo Q, Brunger AT. Structure and topography of the synaptic V-ATPase-synaptophysin complex. Nature 2024; 631:899-904. [PMID: 38838737 PMCID: PMC11269182 DOI: 10.1038/s41586-024-07610-x] [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: 04/09/2024] [Accepted: 05/24/2024] [Indexed: 06/07/2024]
Abstract
Synaptic vesicles are organelles with a precisely defined protein and lipid composition1,2, yet the molecular mechanisms for the biogenesis of synaptic vesicles are mainly unknown. Here we discovered a well-defined interface between the synaptic vesicle V-ATPase and synaptophysin by in situ cryo-electron tomography and single-particle cryo-electron microscopy of functional synaptic vesicles isolated from mouse brains3. The synaptic vesicle V-ATPase is an ATP-dependent proton pump that establishes the proton gradient across the synaptic vesicle, which in turn drives the uptake of neurotransmitters4,5. Synaptophysin6 and its paralogues synaptoporin7 and synaptogyrin8 belong to a family of abundant synaptic vesicle proteins whose function is still unclear. We performed structural and functional studies of synaptophysin-knockout mice, confirming the identity of synaptophysin as an interaction partner with the V-ATPase. Although there is little change in the conformation of the V-ATPase upon interaction with synaptophysin, the presence of synaptophysin in synaptic vesicles profoundly affects the copy number of V-ATPases. This effect on the topography of synaptic vesicles suggests that synaptophysin assists in their biogenesis. In support of this model, we observed that synaptophysin-knockout mice exhibit severe seizure susceptibility, suggesting an imbalance of neurotransmitter release as a physiological consequence of the absence of synaptophysin.
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Affiliation(s)
- Chuchu Wang
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
- Department of Structural Biology, Stanford University, Stanford, CA, USA
- Department of Photon Science, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Wenhong Jiang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Jeremy Leitz
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
- Department of Structural Biology, Stanford University, Stanford, CA, USA
- Department of Photon Science, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Kailu Yang
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
- Department of Structural Biology, Stanford University, Stanford, CA, USA
- Department of Photon Science, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Luis Esquivies
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
- Department of Structural Biology, Stanford University, Stanford, CA, USA
- Department of Photon Science, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Xing Wang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Xiaotao Shen
- Department of Genetics, Stanford University, Stanford, CA, USA
- Stanford Center for Genomics and Personalized Medicine, Stanford University, Stanford, CA, USA
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Richard G Held
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
- Department of Structural Biology, Stanford University, Stanford, CA, USA
- Department of Photon Science, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Daniel J Adams
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Tamara Basta
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Lucas Hampton
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Ruiqi Jian
- Department of Genetics, Stanford University, Stanford, CA, USA
- Stanford Center for Genomics and Personalized Medicine, Stanford University, Stanford, CA, USA
| | - Lihua Jiang
- Department of Genetics, Stanford University, Stanford, CA, USA
- Stanford Center for Genomics and Personalized Medicine, Stanford University, Stanford, CA, USA
| | - Michael H B Stowell
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Wolfgang Baumeister
- Department of Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Qiang Guo
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.
| | - Axel T Brunger
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA.
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.
- Department of Structural Biology, Stanford University, Stanford, CA, USA.
- Department of Photon Science, Stanford University, Stanford, CA, USA.
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA.
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Suder DS, Gonen S. Mitigating the Blurring Effect of CryoEM Averaging on a Flexible and Highly Symmetric Protein Complex through Sub-Particle Reconstruction. Int J Mol Sci 2024; 25:5665. [PMID: 38891853 PMCID: PMC11171969 DOI: 10.3390/ijms25115665] [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: 03/31/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 06/21/2024] Open
Abstract
Many macromolecules are inherently flexible as a feature of their structure and function. During single-particle CryoEM processing, flexible protein regions can be detrimental to high-resolution reconstruction as signals from thousands of particles are averaged together. This "blurring" effect can be difficult to overcome and is possibly more pronounced when averaging highly symmetric complexes. Approaches to mitigating flexibility during CryoEM processing are becoming increasingly critical as the technique advances and is applied to more dynamic proteins and complexes. Here, we detail the use of sub-particle averaging and signal subtraction techniques to precisely target and resolve flexible DARPin protein attachments on a designed tetrahedrally symmetric protein scaffold called DARP14. Particles are first aligned as full complexes, and then the symmetry is reduced by alignment and focused refinement of the constituent subunits. The final reconstructions we obtained were vastly improved over the fully symmetric reconstructions, with observable secondary structure and side-chain placement. Additionally, we were also able to reconstruct the core region of the scaffold to 2.7 Å. The data processing protocol outlined here is applicable to other dynamic and symmetric protein complexes, and our improved maps could allow for new structure-guided variant designs of DARP14.
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Affiliation(s)
| | - Shane Gonen
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, CA 92697, USA
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7
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Huang Z, Han X, Zhao Z, Yang H, Chen H, Gao HJ. Formation and Manipulation of Diatomic Rotors at the Symmetry-Breaking Surfaces of a Kagome Superconductor. NANO LETTERS 2024; 24:6023-6030. [PMID: 38739284 DOI: 10.1021/acs.nanolett.4c00762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
Construction of diatomic rotors, which is crucial for artificial nanomachines, remains challenging due to surface constraints and limited chemical design. Here we report the construction of diatomic Cr-Cs and Fe-Cs rotors where a Cr or Fe atom switches around a Cs atom at the Sb surface of the newly discovered kagome superconductor CsV3Sb5. The switching rate is controlled by the bias voltage between the rotor and scanning tunneling microscope (STM) tip. The spatial distribution of rates exhibits C2 symmetry, possibly linked to the symmetry-breaking charge orders of CsV3Sb5. We have expanded the rotor construction to include different transition metals (Cr, Fe, V) and alkali metals (Cs, K). Remarkably, designed configurations of rotors are achieved through STM manipulation. Rotor orbits and quantum states are precisely controlled by tuning the inter-rotor distance. Our findings establish a novel platform for the controlled fabrication of atomic motors on symmetry-breaking quantum materials, paving the way for advanced nanoscale devices.
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Affiliation(s)
- Zihao Huang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, PR China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Xianghe Han
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, PR China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Zhen Zhao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, PR China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Haitao Yang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, PR China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Hui Chen
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, PR China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Hong-Jun Gao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, PR China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, PR China
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8
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Khan MM, Wilkens S. Molecular mechanism of Oxr1p mediated disassembly of yeast V-ATPase. EMBO Rep 2024; 25:2323-2347. [PMID: 38565737 PMCID: PMC11094088 DOI: 10.1038/s44319-024-00126-5] [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: 12/03/2023] [Revised: 03/07/2024] [Accepted: 03/09/2024] [Indexed: 04/04/2024] Open
Abstract
The eukaryotic vacuolar H+-ATPase (V-ATPase) is regulated by reversible disassembly into autoinhibited V1-ATPase and Vo proton channel subcomplexes. We recently reported that the TLDc protein Oxr1p induces V-ATPase disassembly in vitro. Whether and how Oxr1p is involved in enzyme disassembly in vivo, however, is not known. Here, using yeast genetics and fluorescence microscopy, we show that Oxr1p is essential for efficient V-ATPase disassembly in the cell. Supporting biochemical and biophysical in vitro experiments show that whereas Oxr1p-driven holoenzyme disassembly can occur in the absence of nucleotides, the presence of ATP greatly accelerates the process. ATP hydrolysis is needed, however, for subsequent release of Oxr1p so that the free V1 can adopt the autoinhibited conformation. Overall, our study unravels the molecular mechanism of Oxr1p-induced disassembly that occurs in vivo as part of the canonical V-ATPase regulation by reversible disassembly.
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Affiliation(s)
- Md Murad Khan
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA
| | - Stephan Wilkens
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA.
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9
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Guo B, Li QY, Liu XJ, Luo GH, Wu YJ, Nie J. Diabetes mellitus and Alzheimer's disease: Vacuolar adenosine triphosphatase as a potential link. Eur J Neurosci 2024; 59:2577-2595. [PMID: 38419188 DOI: 10.1111/ejn.16286] [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: 12/01/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 03/02/2024]
Abstract
Globally, the incidence of diabetes mellitus (DM) and Alzheimer's disease (AD) is increasing year by year, causing a huge economic and social burden, and their pathogenesis and aetiology have been proven to have a certain correlation. In recent years, more and more studies have shown that vacuolar adenosine triphosphatases (v-ATPases) in eukaryotes, which are biomolecules regulating lysosomal acidification and glycolipid metabolism, play a key role in DM and AD. This article describes the role of v-ATPase in DM and AD, including its role in glycolysis, insulin secretion and insulin resistance (IR), as well as its relationship with lysosomal acidification, autophagy and β-amyloid (Aβ). In DM, v-ATPase is involved in the regulation of glucose metabolism and IR. v-ATPase is closely related to glycolysis. On the one hand, v-ATPase affects the rate of glycolysis by affecting the secretion of insulin and changing the activities of key glycolytic enzymes hexokinase (HK) and phosphofructokinase 1 (PFK-1). On the other hand, glucose is the main regulator of this enzyme, and the assembly and activity of v-ATPase depend on glucose, and glucose depletion will lead to its decomposition and inactivation. In addition, v-ATPase can also regulate free fatty acids, thereby improving IR. In AD, v-ATPase can not only improve the abnormal brain energy metabolism by affecting lysosomal acidification and autophagy but also change the deposition of Aβ by affecting the production and degradation of Aβ. Therefore, v-ATPase may be the bridge between DM and AD.
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Affiliation(s)
- Bin Guo
- Key Laboratory of Basic Pharmacology of the Ministry of Education and Joint International Research Laboratory of Ethnomedicine of the Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
| | - Qi-Ye Li
- Key Laboratory of Basic Pharmacology of the Ministry of Education and Joint International Research Laboratory of Ethnomedicine of the Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
| | - Xue-Jia Liu
- Key Laboratory of Basic Pharmacology of the Ministry of Education and Joint International Research Laboratory of Ethnomedicine of the Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
| | - Guo-Hui Luo
- Key Laboratory of Basic Pharmacology of the Ministry of Education and Joint International Research Laboratory of Ethnomedicine of the Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
| | - Ya-Juan Wu
- Key Laboratory of Basic Pharmacology of the Ministry of Education and Joint International Research Laboratory of Ethnomedicine of the Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
| | - Jing Nie
- Key Laboratory of Basic Pharmacology of the Ministry of Education and Joint International Research Laboratory of Ethnomedicine of the Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
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10
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Yanagisawa S, Bukhari ZA, Parra KJ, Frasch WD. Eukaryotic yeast V 1-ATPase rotary mechanism insights revealed by high-resolution single-molecule studies. Front Mol Biosci 2024; 11:1269040. [PMID: 38567099 PMCID: PMC10985318 DOI: 10.3389/fmolb.2024.1269040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 02/07/2024] [Indexed: 04/04/2024] Open
Abstract
Vacuolar ATP-dependent proton pumps (V-ATPases) belong to a super-family of rotary ATPases and ATP synthases. The V1 complex consumes ATP to drive rotation of a central rotor that pumps protons across membranes via the Vo complex. Eukaryotic V-ATPases are regulated by reversible disassembly of subunit C, V1 without C, and VO. ATP hydrolysis is thought to generate an unknown rotary state that initiates regulated disassembly. Dissociated V1 is inhibited by subunit H that traps it in a specific rotational position. Here, we report the first single-molecule studies with high resolution of time and rotational position of Saccharomyces cerevisiae V1-ATPase lacking subunits H and C (V1ΔHC), which resolves previously elusive dwells and angular velocity changes. Rotation occurred in 120° power strokes separated by dwells comparable to catalytic dwells observed in other rotary ATPases. However, unique V1ΔHC rotational features included: 1) faltering power stroke rotation during the first 60°; 2) a dwell often occurring ∼45° after the catalytic dwell, which did not increase in duration at limiting MgATP; 3) a second dwell, ∼2-fold longer occurring 112° that increased in duration and occurrence at limiting MgATP; 4) limiting MgATP-dependent decreases in power stroke angular velocity where dwells were not observed. The results presented here are consistent with MgATP binding to the empty catalytic site at 112° and MgADP released at ∼45°, and provide important new insight concerning the molecular basis for the differences in rotary positions of substrate binding and product release between V-type and F-type ATPases.
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Affiliation(s)
- Seiga Yanagisawa
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Zain A. Bukhari
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Karlett J. Parra
- Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine, Albuquerque, NM, United States
| | - Wayne D. Frasch
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
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11
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Li B, Lan S, Liu XR, Ji JJ, He YY, Zhang DM, Xu J, Sun H, Shi Z, Wang J, Tian Y. ATP6V1A variants are associated with childhood epilepsy with favorable outcome. Seizure 2024; 116:81-86. [PMID: 37574426 DOI: 10.1016/j.seizure.2023.08.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 08/03/2023] [Accepted: 08/06/2023] [Indexed: 08/15/2023] Open
Abstract
PURPOSE ATP6V1A variants have been identified in patients with highly variable phenotypes such as autosomal dominant epileptic encephalopathy and autosomal recessive cutis laxa. However, the mechanism underlying phenotype variation is unknown. We screened ATP6V1A variants in patients with epilepsy and analyzed the genotype-phenotype correlation to explain the mechanism underlying phenotypic variations. METHODS We performed trio-based whole-exome sequencing in people with epilepsy without acquired causes. All previously reported ATP6V1A variants were systematically retrieved from the HGMD and PubMed databases. RESULTS Three novel de novo ATP6V1A variants, including c.749G>C/p.Gly250Ala, c.782A>G/p.Gln261Arg, and c.1103T>C/p.Met368Thr, were identified in three unrelated cases with childhood focal (partial) epilepsy. None of the variants were listed in any public population database and evaluated as likely pathogenic according to the criteria of the American College of Medical Genetics and Genomics (ACMG). All persons showed good responses to anti-seizure medication and psychomotor development was normal. Further analysis showed that monoallelic missense variants were associated with epilepsy with variable severity, whereas biallelic variants resulted in developmental abnormalities of multisystem that may result in early lethality. CONCLUSION Childhood focal epilepsy with favorable outcome was probably a novel phenotype of ATP6V1A. ATP6V1A variants are associated with a range of phenotypes that correlate with genotypes. The relationship between phenotype severity and the genotype (genetic impairment) of ATP6V1A variants helps explain the phenotypic variations.
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Affiliation(s)
- Bin Li
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Song Lan
- Department of Neurology, Maoming People's Hospital, Maoming, China
| | - Xiao-Rong Liu
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Jing-Jing Ji
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Yun-Yan He
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Dong-Ming Zhang
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Jie Xu
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China
| | - Hui Sun
- Department of Neurology, the First Affiliated Hospital of Guangzhou Medical University
| | - Zhen Shi
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China
| | - Jie Wang
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China.
| | - Yang Tian
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, China; Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, China.
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12
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Chu A, Yao Y, Glibowicka M, Deber CM, Manolson MF. The Human Mutation K237_V238del in a Putative Lipid Binding Motif within the V-ATPase a2 Isoform Suggests a Molecular Mechanism Underlying Cutis Laxa. Int J Mol Sci 2024; 25:2170. [PMID: 38396846 PMCID: PMC10889665 DOI: 10.3390/ijms25042170] [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: 12/29/2023] [Revised: 01/19/2024] [Accepted: 02/01/2024] [Indexed: 02/25/2024] Open
Abstract
Vacuolar ATPases (V-ATPases), proton pumps composed of 16 subunits, are necessary for a variety of cellular functions. Subunit "a" has four isoforms, a1-a4, each with a distinct cellular location. We identified a phosphoinositide (PIP) interaction motif, KXnK(R)IK(R), conserved in all four isoforms, and hypothesize that a/PIP interactions regulate V-ATPase recruitment/retention to different organelles. Among the four isoforms, a2 is enriched on Golgi with a2 mutations in the PIP motif resulting in cutis laxa. We hypothesize that the hydrophilic N-terminal (NT) domain of a2 contains a lipid-binding domain, and mutations in this domain prevent interaction with Golgi-enriched PIPs, resulting in cutis laxa. We recreated the cutis laxa-causing mutation K237_V238del, and a double mutation in the PIP-binding motif, K237A/V238A. Circular dichroism confirmed that there were no protein structure alterations. Pull-down assays with PIP-enriched liposomes revealed that wildtype a2NT preferentially binds phosphatidylinositol 4-phosphate (PI(4)P), while mutants decreased binding to PI(4)P. In HEK293 cells, wildtype a2NT was localized to Golgi and co-purified with microsomal membranes. Mutants reduced Golgi localization and membrane association. Rapamycin depletion of PI(4)P diminished a2NT-Golgi localization. We conclude that a2NT is sufficient for Golgi retention, suggesting the lipid-binding motif is involved in V-ATPase targeting and/or retention. Mutational analyses suggest a molecular mechanism underlying how a2 mutations result in cutis laxa.
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Affiliation(s)
- Anh Chu
- Faculty of Dentistry, University of Toronto, Toronto M5G 1G6, ON, Canada; (A.C.); (Y.Y.)
| | - Yeqi Yao
- Faculty of Dentistry, University of Toronto, Toronto M5G 1G6, ON, Canada; (A.C.); (Y.Y.)
| | - Miroslawa Glibowicka
- Division of Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto M5G 0A4, ON, Canada; (M.G.); (C.M.D.)
| | - Charles M. Deber
- Division of Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto M5G 0A4, ON, Canada; (M.G.); (C.M.D.)
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto M5S 1A8, ON, Canada
| | - Morris F. Manolson
- Faculty of Dentistry, University of Toronto, Toronto M5G 1G6, ON, Canada; (A.C.); (Y.Y.)
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto M5S 1A8, ON, Canada
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13
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Zhang L, Tang F. Molecular mechanism of Serratia marcescens Bizio infection in Reticulitermes chinensis Snyder based on full-length SMRT transcriptome sequencing. BULLETIN OF ENTOMOLOGICAL RESEARCH 2024:1-13. [PMID: 38328866 DOI: 10.1017/s000748532300072x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Reticulitermes chinensis Snyder is an important pest in forestry and construction and is widely distributed in China. We found that Serratia marcescens Bizio strain SM1 has insecticidal activity to R. chinensis, but the pathogenic mechanism of SM1 to R. chinensis is not clear. Therefore, full-length transcriptome sequencing was performed on R. chinensis infected with SM1 and the control group. A total of 230 differentially expressed genes were identified by comparing SM1 infection group and the control group, among which 103 were downregulated and 127 were upregulated. We found downregulated genes in nine metabolic pathway categories, among which carbohydrate metabolism had the most downregulated genes, followed by energy metabolism and amino acid metabolism. We also found that some downregulated genes were related to pattern recognition receptors, cellular immunity, and humoral immunity, indicating that R. chinensis immunity was negatively affected by SM1 infection. In addition, some genes in signal transduction and genetic information processing pathways were downregulated. In this study, high-throughput full-length transcriptome analysis was used to analyse the pathogenic mechanism of SM1 to R. chinensis. The results of this study provide useful information for exploring the relationship between SM1 and R. chinensis, and provide theoretical support for the future application of SM1 and the prevention and treatment of R. chinensis.
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Affiliation(s)
- Ling Zhang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, People's Republic of China
- College of Forestry, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Fang Tang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, People's Republic of China
- College of Forestry, Nanjing Forestry University, Nanjing 210037, People's Republic of China
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14
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Radka CD, Grace CR, Hasdemir HS, Li Y, Rodriguez CC, Rodrigues P, Oldham ML, Qayyum MZ, Pitre A, MacCain WJ, Kalathur RC, Tajkhorshid E, Rock CO. The carboxy terminus causes interfacial assembly of oleate hydratase on a membrane bilayer. J Biol Chem 2024; 300:105627. [PMID: 38211817 PMCID: PMC10847778 DOI: 10.1016/j.jbc.2024.105627] [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: 11/15/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 01/13/2024] Open
Abstract
The soluble flavoprotein oleate hydratase (OhyA) hydrates the 9-cis double bond of unsaturated fatty acids. OhyA substrates are embedded in membrane bilayers; OhyA must remove the fatty acid from the bilayer and enclose it in the active site. Here, we show that the positively charged helix-turn-helix motif in the carboxy terminus (CTD) is responsible for interacting with the negatively charged phosphatidylglycerol (PG) bilayer. Super-resolution microscopy of Staphylococcus aureus cells expressing green fluorescent protein fused to OhyA or the CTD sequence shows subcellular localization along the cellular boundary, indicating OhyA is membrane-associated and the CTD sequence is sufficient for membrane recruitment. Using cryo-electron microscopy, we solved the OhyA dimer structure and conducted 3D variability analysis of the reconstructions to assess CTD flexibility. Our surface plasmon resonance experiments corroborated that OhyA binds the PG bilayer with nanomolar affinity and we found the CTD sequence has intrinsic PG binding properties. We determined that the nuclear magnetic resonance structure of a peptide containing the CTD sequence resembles the OhyA crystal structure. We observed intermolecular NOE from PG liposome protons next to the phosphate group to the CTD peptide. The addition of paramagnetic MnCl2 indicated the CTD peptide binds the PG surface but does not insert into the bilayer. Molecular dynamics simulations, supported by site-directed mutagenesis experiments, identify key residues in the helix-turn-helix that drive membrane association. The data show that the OhyA CTD binds the phosphate layer of the PG surface to obtain bilayer-embedded unsaturated fatty acids.
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Affiliation(s)
- Christopher D Radka
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA; Department of Host Microbe Interactions, St Jude Children's Research Hospital, Memphis, Tennessee, USA.
| | - Christy R Grace
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Hale S Hasdemir
- Theoretical and Computational Biophysics Group, Department of Biochemistry, and Center for Biophysics and Quantitative Biology, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Yupeng Li
- Theoretical and Computational Biophysics Group, Department of Biochemistry, and Center for Biophysics and Quantitative Biology, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Carlos C Rodriguez
- Theoretical and Computational Biophysics Group, Department of Biochemistry, and Center for Biophysics and Quantitative Biology, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Patrick Rodrigues
- Hartwell Center of Biotechnology, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Michael L Oldham
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - M Zuhaib Qayyum
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Aaron Pitre
- Cell and Tissue Imaging Center, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - William J MacCain
- Department of Host Microbe Interactions, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Ravi C Kalathur
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Emad Tajkhorshid
- Theoretical and Computational Biophysics Group, Department of Biochemistry, and Center for Biophysics and Quantitative Biology, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Charles O Rock
- Department of Host Microbe Interactions, St Jude Children's Research Hospital, Memphis, Tennessee, USA
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15
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Jiang YT, Yang LH, Zheng JX, Geng XC, Bai YX, Wang YC, Xue HW, Lin WH. Vacuolar H +-ATPase and BZR1 form a feedback loop to regulate the homeostasis of BR signaling in Arabidopsis. MOLECULAR PLANT 2023; 16:1976-1989. [PMID: 37837193 DOI: 10.1016/j.molp.2023.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 09/29/2023] [Accepted: 10/10/2023] [Indexed: 10/15/2023]
Abstract
Brassinosteroid (BR) is a vital plant hormone that regulates plant growth and development. BRASSINAZOLE RESISTANT 1 (BZR1) is a key transcription factor in BR signaling, and its nucleocytoplasmic localization is crucial for BR signaling. However, the mechanisms that regulate BZR1 nucleocytoplasmic distribution and thus the homeostasis of BR signaling remain largely unclear. The vacuole is the largest organelle in mature plant cells and plays a key role in maintenance of cellular pH, storage of intracellular substances, and transport of ions. In this study, we uncovered a novel mechanism of BR signaling homeostasis regulated by the vacuolar H+-ATPase (V-ATPase) and BZR1 feedback loop. Our results revealed that the vha-a2 vha-a3 mutant (vha2, lacking V-ATPase activity) exhibits enhanced BR signaling with increased total amount of BZR1, nuclear-localized BZR1, and the ratio of BZR1/phosphorylated BZR1 in the nucleus. Further biochemical assays revealed that VHA-a2 and VHA-a3 of V-ATPase interact with the BZR1 protein through a domain that is conserved across multiple species. VHA-a2 and VHA-a3 negatively regulate BR signaling by interacting with BZR1 and promoting its retention in the tonoplast. Interestingly, a series of molecular analyses demonstrated that nuclear-localized BZR1 could bind directly to specific motifs in the promoters of VHA-a2 and VHA-a3 to promote their expression. Taken together, these results suggest that V-ATPase and BZR1 may form a feedback regulatory loop to maintain the homeostasis of BR signaling in Arabidopsis, providing new insights into vacuole-mediated regulation of hormone signaling.
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Affiliation(s)
- Yu-Tong Jiang
- School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Collaborative Innovation Center of Agri-Seeds, Joint Center for Single Cell Biology, Shanghai 200240, China; School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Lu-Han Yang
- School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ji-Xuan Zheng
- Zhiyuan College, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xian-Chen Geng
- School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yu-Xuan Bai
- Zhiyuan College, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yu-Chen Wang
- Zhiyuan College, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hong-Wei Xue
- Shanghai Collaborative Innovation Center of Agri-Seeds, Joint Center for Single Cell Biology, Shanghai 200240, China; School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Wen-Hui Lin
- School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Collaborative Innovation Center of Agri-Seeds, Joint Center for Single Cell Biology, Shanghai 200240, China.
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16
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Mitra C, Winkley S, Kane PM. Human V-ATPase a-subunit isoforms bind specifically to distinct phosphoinositide phospholipids. J Biol Chem 2023; 299:105473. [PMID: 37979916 PMCID: PMC10755780 DOI: 10.1016/j.jbc.2023.105473] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 10/31/2023] [Accepted: 11/06/2023] [Indexed: 11/20/2023] Open
Abstract
Vacuolar H+-ATPases (V-ATPases) are highly conserved multisubunit enzymes that maintain the distinct pH of eukaryotic organelles. The integral membrane a-subunit is encoded by tissue- and organelle-specific isoforms, and its cytosolic N-terminal domain (aNT) modulates organelle-specific regulation and targeting of V-ATPases. Organelle membranes have specific phosphatidylinositol phosphate (PIP) lipid enrichment linked to maintenance of organelle pH. In yeast, the aNT domains of the two a-subunit isoforms bind PIP lipids enriched in the organelle membranes where they reside; these interactions affect activity and regulatory properties of the V-ATPases containing each isoform. Humans have four a-subunit isoforms, and we hypothesize that the aNT domains of these isoforms will also bind to specific PIP lipids. The a1 and a2 isoforms of human V-ATPase a-subunits are localized to endolysosomes and Golgi, respectively. We determined that bacterially expressed Hua1NT and Hua2NT bind specifically to endolysosomal PIP lipids PI(3)P and PI(3,5)P2 and Golgi enriched PI(4)P, respectively. Despite the lack of canonical PIP-binding sites, we identified potential binding sites in the HuaNT domains by sequence comparisons and existing subunit structures and models. We found that mutations at a similar location in the distal loops of both HuaNT isoforms compromise binding to their cognate PIP lipids, suggesting that these loops encode PIP specificity of the a-subunit isoforms. These data suggest a mechanism through which PIP lipid binding could stabilize and activate V-ATPases in distinct organelles.
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Affiliation(s)
- Connie Mitra
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Samuel Winkley
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Patricia M Kane
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York, USA.
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17
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Jitapunkul K, Zhao Y, Lawtrakul L, Van Hove MA, Zhang R. Rotations of F-ATPase and V-ATPase analyzed by a torque approach. J Biomol Struct Dyn 2023; 41:10368-10376. [PMID: 36495307 DOI: 10.1080/07391102.2022.2154847] [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: 08/23/2022] [Accepted: 11/28/2022] [Indexed: 12/14/2022]
Abstract
F-type ATP synthase (F-ATPase) and vacuolar ATP hydrolase (V-ATPase) are well-known biomolecular motors, which play significant catalytic roles in ATP synthesis and ATP hydrolysis reactions. Their rotational torques are important factors involved in their rotational behavior that can be measured experimentally but with considerable difficulty. To overcome this difficulty and thereby provide an in-depth understanding of their operation mechanism, we herein carry out simple and fast computer modelling to study the two proteins, using our torque approach that relies on interatomic forces and coordinates of unequilibrated configurations taken from brief molecular dynamics (MD) simulations. As predicted by the torque approach, F-ATPase is demonstrated to be a random rotor, but it prefers to rotate in clockwise direction (as seen from the membrane toward the protein) for ATP synthesis, owing to the predominantly negative angle-averaged torques. By contrast, V-ATPase tends to rotate only in counterclockwise direction for ATP hydrolysis, due to the almost uniform averaged positive torques generated by the unidirectional rotation near the three catalytic sites. The rotational behaviors of both proteins are also affected by the surrounding solvent which can promote or hinder the internal rotation. By combining the torque approach with classic force-field MD simulations, the torques of two biomolecular motors can be calculated economically, and are found to agree with previous experiments and theoretical calculations. This work demonstrates that our torque approach can be extended to the field of biology and can help gain a deeper insight into the mechanistic rotation of biomolecular motors with modest computation time.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Kulpavee Jitapunkul
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China
- School of Bio-Chemical Engineering, Sirindhorn International Institute of Technology (SIIT), Thammasat University, Pathum Thani, Thailand
| | - Yanling Zhao
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China
- Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China
| | - Luckhana Lawtrakul
- School of Bio-Chemical Engineering, Sirindhorn International Institute of Technology (SIIT), Thammasat University, Pathum Thani, Thailand
| | - Michel A Van Hove
- Institute of Computational and Theoretical Studies & Department of Physics, Hong Kong Baptist University, Hong Kong SAR, China
| | - Ruiqin Zhang
- Department of Physics, City University of Hong Kong, Hong Kong SAR, China
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18
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DiIorio MC, Kulczyk AW. Novel Artificial Intelligence-Based Approaches for Ab Initio Structure Determination and Atomic Model Building for Cryo-Electron Microscopy. MICROMACHINES 2023; 14:1674. [PMID: 37763837 PMCID: PMC10534518 DOI: 10.3390/mi14091674] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/21/2023] [Accepted: 08/25/2023] [Indexed: 09/29/2023]
Abstract
Single particle cryo-electron microscopy (cryo-EM) has emerged as the prevailing method for near-atomic structure determination, shedding light on the important molecular mechanisms of biological macromolecules. However, the inherent dynamics and structural variability of biological complexes coupled with the large number of experimental images generated by a cryo-EM experiment make data processing nontrivial. In particular, ab initio reconstruction and atomic model building remain major bottlenecks that demand substantial computational resources and manual intervention. Approaches utilizing recent innovations in artificial intelligence (AI) technology, particularly deep learning, have the potential to overcome the limitations that cannot be adequately addressed by traditional image processing approaches. Here, we review newly proposed AI-based methods for ab initio volume generation, heterogeneous 3D reconstruction, and atomic model building. We highlight the advancements made by the implementation of AI methods, as well as discuss remaining limitations and areas for future development.
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Affiliation(s)
- Megan C. DiIorio
- Institute for Quantitative Biomedicine, Rutgers University, 174 Frelinghuysen Road, Piscataway, NJ 08854, USA
| | - Arkadiusz W. Kulczyk
- Institute for Quantitative Biomedicine, Rutgers University, 174 Frelinghuysen Road, Piscataway, NJ 08854, USA
- Department of Biochemistry & Microbiology, Rutgers University, 76 Lipman Drive, New Brunswick, NJ 08901, USA
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19
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Burton-Smith RN, Song C, Ueno H, Murata T, Iino R, Murata K. Six states of Enterococcus hirae V-type ATPase reveals non-uniform rotor rotation during turnover. Commun Biol 2023; 6:755. [PMID: 37507515 PMCID: PMC10382590 DOI: 10.1038/s42003-023-05110-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
The vacuolar-type ATPase from Enterococcus hirae (EhV-ATPase) is a thus-far unique adaptation of V-ATPases, as it performs Na+ transport and demonstrates an off-axis rotor assembly. Recent single molecule studies of the isolated V1 domain have indicated that there are subpauses within the three major states of the pseudo three-fold symmetric rotary enzyme. However, there was no structural evidence for these. Herein we activate the EhV-ATPase complex with ATP and identified multiple structures consisting of a total of six states of this complex by using cryo-electron microscopy. The orientations of the rotor complex during turnover, especially in the intermediates, are not as perfectly uniform as expected. The densities in the nucleotide binding pockets in the V1 domain indicate the different catalytic conditions for the six conformations. The off-axis rotor and its' interactions with the stator a-subunit during rotation suggests that this non-uniform rotor rotation is performed through the entire complex.
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Affiliation(s)
- Raymond N Burton-Smith
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan
- National Institute for Physiological Sciences, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan
| | - Chihong Song
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan
- National Institute for Physiological Sciences, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan
- Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan
| | - Hiroshi Ueno
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo, 113-8656, Japan
| | - Takeshi Murata
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-Cho, Inage-Ku, Chiba, 263-8522, Japan
| | - Ryota Iino
- Institute for Molecular Science, National Institute for Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan
- Department of Functional Molecular Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI), 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8585, Japan
| | - Kazuyoshi Murata
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.
- National Institute for Physiological Sciences, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.
- Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.
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20
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Im E, Jiang Y, Stavrides PH, Darji S, Erdjument-Bromage H, Neubert TA, Choi JY, Wegiel J, Lee JH, Nixon RA. Lysosomal dysfunction in Down syndrome and Alzheimer mouse models is caused by v-ATPase inhibition by Tyr 682-phosphorylated APP βCTF. SCIENCE ADVANCES 2023; 9:eadg1925. [PMID: 37494443 PMCID: PMC10371027 DOI: 10.1126/sciadv.adg1925] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 06/23/2023] [Indexed: 07/28/2023]
Abstract
Lysosome dysfunction arises early and propels Alzheimer's disease (AD). Herein, we show that amyloid precursor protein (APP), linked to early-onset AD in Down syndrome (DS), acts directly via its β-C-terminal fragment (βCTF) to disrupt lysosomal vacuolar (H+)-adenosine triphosphatase (v-ATPase) and acidification. In human DS fibroblasts, the phosphorylated 682YENPTY internalization motif of APP-βCTF binds selectively within a pocket of the v-ATPase V0a1 subunit cytoplasmic domain and competitively inhibits association of the V1 subcomplex of v-ATPase, thereby reducing its activity. Lowering APP-βCTF Tyr682 phosphorylation restores v-ATPase and lysosome function in DS fibroblasts and in vivo in brains of DS model mice. Notably, lowering APP-βCTF Tyr682 phosphorylation below normal constitutive levels boosts v-ATPase assembly and activity, suggesting that v-ATPase may also be modulated tonically by phospho-APP-βCTF. Elevated APP-βCTF Tyr682 phosphorylation in two mouse AD models similarly disrupts v-ATPase function. These findings offer previously unknown insight into the pathogenic mechanism underlying faulty lysosomes in all forms of AD.
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Affiliation(s)
- Eunju Im
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ying Jiang
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Philip H. Stavrides
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
| | - Sandipkumar Darji
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
| | - Hediye Erdjument-Bromage
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Thomas A. Neubert
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Jun Yong Choi
- Department of Chemistry and Biochemistry, Queens College, Queens, NY 11367, USA
- Ph.D. Programs in Chemistry and Biochemistry, The Graduate Center of the City University of New York, New York, NY 10016, USA
| | - Jerzy Wegiel
- Department of Developmental Neurobiology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY 10314, USA
| | - Ju-Hyun Lee
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ralph A. Nixon
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
- NYU Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, USA
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21
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Indrawinata K, Argiropoulos P, Sugita S. Structural and functional understanding of disease-associated mutations in V-ATPase subunit a1 and other isoforms. Front Mol Neurosci 2023; 16:1135015. [PMID: 37465367 PMCID: PMC10352029 DOI: 10.3389/fnmol.2023.1135015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 06/09/2023] [Indexed: 07/20/2023] Open
Abstract
The vacuolar-type ATPase (V-ATPase) is a multisubunit protein composed of the cytosolic adenosine triphosphate (ATP) hydrolysis catalyzing V1 complex, and the integral membrane complex, Vo, responsible for proton translocation. The largest subunit of the Vo complex, subunit a, enables proton translocation upon ATP hydrolysis, mediated by the cytosolic V1 complex. Four known subunit a isoforms (a1-a4) are expressed in different cellular locations. Subunit a1 (also known as Voa1), the neural isoform, is strongly expressed in neurons and is encoded by the ATP6V0A1 gene. Global knockout of this gene in mice causes embryonic lethality, whereas pyramidal neuron-specific knockout resulted in neuronal cell death with impaired spatial and learning memory. Recently reported, de novo and biallelic mutations of the human ATP6V0A1 impair autophagic and lysosomal activities, contributing to neuronal cell death in developmental and epileptic encephalopathies (DEE) and early onset progressive myoclonus epilepsy (PME). The de novo heterozygous R740Q mutation is the most recurrent variant reported in cases of DEE. Homology studies suggest R740 deprotonates protons from specific glutamic acid residues in subunit c, highlighting its importance to the overall V-ATPase function. In this paper, we discuss the structure and mechanism of the V-ATPase, emphasizing how mutations in subunit a1 can lead to lysosomal and autophagic dysfunction in neurodevelopmental disorders, and how mutations to the non-neural isoforms, a2-a4, can also lead to various genetic diseases. Given the growing discovery of disease-causing variants of V-ATPase subunit a and its function as a pump-based regulator of intracellular organelle pH, this multiprotein complex warrants further investigation.
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Affiliation(s)
- Karen Indrawinata
- Division of Translational and Experimental Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
| | - Peter Argiropoulos
- Division of Translational and Experimental Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
| | - Shuzo Sugita
- Division of Translational and Experimental Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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22
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Wilkens S, Khan MM, Knight K, Oot R. Tender love and disassembly: How a TLDc domain protein breaks the V-ATPase. Bioessays 2023; 45:e2200251. [PMID: 37183929 PMCID: PMC10392918 DOI: 10.1002/bies.202200251] [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: 12/31/2022] [Revised: 04/13/2023] [Accepted: 05/03/2023] [Indexed: 05/16/2023]
Abstract
Vacuolar ATPases (V-ATPases, V1 Vo -ATPases) are rotary motor proton pumps that acidify intracellular compartments, and, when localized to the plasma membrane, the extracellular space. V-ATPase is regulated by a unique process referred to as reversible disassembly, wherein V1 -ATPase disengages from Vo proton channel in response to diverse environmental signals. Whereas the disassembly step of this process is ATP dependent, the (re)assembly step is not, but requires the action of a heterotrimeric chaperone referred to as the RAVE complex. Recently, an alternative pathway of holoenzyme disassembly was discovered that involves binding of Oxidation Resistance 1 (Oxr1p), a poorly characterized protein implicated in oxidative stress response. Unlike conventional reversible disassembly, which depends on enzyme activity, Oxr1p induced dissociation can occur in absence of ATP. Yeast Oxr1p belongs to the family of TLDc domain containing proteins that are conserved from yeast to mammals, and have been implicated in V-ATPase function in a variety of tissues. This brief perspective summarizes what we know about the molecular mechanisms governing both reversible (ATP dependent) and Oxr1p driven (ATP independent) V-ATPase dissociation into autoinhibited V1 and Vo subcomplexes.
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Affiliation(s)
- Stephan Wilkens
- Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY
| | - Md. Murad Khan
- Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY
| | - Kassidy Knight
- Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY
| | - Rebecca Oot
- Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY
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23
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Wang H, Rubinstein JL. CryoEM of V-ATPases: Assembly, disassembly, and inhibition. Curr Opin Struct Biol 2023; 80:102592. [PMID: 37272327 DOI: 10.1016/j.sbi.2023.102592] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 03/13/2023] [Accepted: 03/16/2023] [Indexed: 06/06/2023]
Abstract
Vacuolar-type ATPases (V-ATPases) are responsible for the acidification of intracellular compartments in almost all eukaryotic cells, while in some specialized cells they acidify the extracellular environment. As ubiquitous proton pumps, these large membrane-embedded enzymes are involved in many fundamental cellular processes that require tight control of pH. Consequently, V-ATPase malfunction or aberrant activity has been linked to numerous diseases. In the past ten years, electron cryomicroscopy (cryoEM) of yeast V-ATPases has revealed the architecture and rotary catalytic mechanism of these macromolecular machines. More recently, studies have revealed the structures of V-ATPases in animals and plants, uncovered aspects of how V-ATPases are assembled and regulated by reversible dissociation, and shown how V-ATPase activity can be modulated by proteins and small molecule inhibitors. In this review, we highlight these recent developments.
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Affiliation(s)
- Hanlin Wang
- Molecular Medicine Program, The Hospital for Sick Children, M5G 0A4, Toronto, Canada; Department of Biochemistry, The University of Toronto, M5G 1L7, Toronto, Canada
| | - John L Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, M5G 0A4, Toronto, Canada; Department of Biochemistry, The University of Toronto, M5G 1L7, Toronto, Canada; Department of Medical Biophysics, The University of Toronto, M5S 1A8, Toronto, Canada.
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24
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Mitra C, Kane PM. Human V-ATPase a-subunit isoforms bind specifically to distinct phosphoinositide phospholipids. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.24.538068. [PMID: 37162989 PMCID: PMC10168244 DOI: 10.1101/2023.04.24.538068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
V-ATPases are highly conserved multi-subunit enzymes that maintain the distinct pH of eukaryotic organelles. The integral membrane a-subunit is encoded by tissue and organelle specific isoforms, and its cytosolic N-terminal domain (aNT) modulates organelle specific regulation and targeting of V-ATPases. Organelle membranes have specific phosphatidylinositol phosphate (PIP) lipid enrichment linked to maintenance of organelle pH. In yeast, the aNT domains of the two a-subunit isoforms bind PIP lipids enriched in the organelle membranes where they reside; these interactions affect activity and regulatory properties of the V-ATPases containing each isoform. Humans have four a-subunit isoforms. We hypothesize that the aNT domains of the human isoforms will also bind to specific PIP lipids. The a1 and a2 isoforms of human V-ATPase a-subunits are localized to endolysosomes and Golgi, respectively. Bacterially expressed Hua1NT and Hua2NT bind specifically to endolysosomal PIP lipids PI(3)P and PI(3,5)P2 and Golgi enriched PI(4)P, respectively. Despite the lack of canonical PIP binding sites, potential binding sites in the HuaNT domains were identified by sequence comparisons and existing subunit structures and models. Mutations at a similar location in the distal loops of both HuaNT isoforms compromise binding to their cognate PIP lipids, suggesting that these loops encode PIP specificity of the a-subunit isoforms. These data also suggest a mechanism through which PIP lipid binding could stabilize and activate V-ATPases in distinct organelles.
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Affiliation(s)
- Connie Mitra
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY
| | - Patricia M Kane
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY
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25
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Characterization of a PIP Binding Site in the N-Terminal Domain of V-ATPase a4 and Its Role in Plasma Membrane Association. Int J Mol Sci 2023; 24:ijms24054867. [PMID: 36902293 PMCID: PMC10002524 DOI: 10.3390/ijms24054867] [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: 01/30/2023] [Revised: 02/13/2023] [Accepted: 02/21/2023] [Indexed: 03/06/2023] Open
Abstract
Vacuolar ATPases (V-ATPases) are multi-subunit ATP-dependent proton pumps necessary for cellular functions, including pH regulation and membrane fusion. The evidence suggests that the V-ATPase a-subunit's interaction with the membrane signaling lipid phosphatidylinositol (PIPs) regulates the recruitment of V-ATPase complexes to specific membranes. We generated a homology model of the N-terminal domain of the human a4 isoform (a4NT) using Phyre2.0 and propose a lipid binding domain within the distal lobe of the a4NT. We identified a basic motif, K234IKK237, critical for interaction with phosphoinositides (PIP), and found similar basic residue motifs in all four mammalian and both yeast a-isoforms. We tested PIP binding of wildtype and mutant a4NT in vitro. In protein lipid overlay assays, the double mutation K234A/K237A and the autosomal recessive distal renal tubular-causing mutation K237del reduced both PIP binding and association with liposomes enriched with PI(4,5)P2, a PIP enriched within plasma membranes. Circular dichroism spectra of the mutant protein were comparable to wildtype, indicating that mutations affected lipid binding, not protein structure. When expressed in HEK293, wildtype a4NT localized to the plasma membrane in fluorescence microscopy and co-purified with the microsomal membrane fraction in cellular fractionation experiments. a4NT mutants showed reduced membrane association and decreased plasma membrane localization. Depletion of PI(4,5)P2 by ionomycin caused reduced membrane association of the WT a4NT protein. Our data suggest that information contained within the soluble a4NT is sufficient for membrane association and that PI(4,5)P2 binding capacity is involved in a4 V-ATPase plasma membrane retention.
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26
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Tuli F, Kane PM. Chimeric a-subunit isoforms generate functional yeast V-ATPases with altered regulatory properties in vitro and in vivo. Mol Biol Cell 2023; 34:ar14. [PMID: 36598799 PMCID: PMC10011726 DOI: 10.1091/mbc.e22-07-0265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
V-ATPases are highly regulated proton pumps that acidify organelles. The V-ATPase a-subunit is a two-domain protein containing a C-terminal transmembrane domain responsible for proton transport and an N-terminal cytosolic domain (aNT) that is a regulatory hub, integrating environmental inputs to regulate assembly, localization, and V-ATPase activity. The yeast Saccharomyces cerevisiae encodes only two organelle-specific a-isoforms, Stv1 in the Golgi and Vph1 in the vacuole. On the basis of recent structures, we designed chimeric yeast aNTs in which the globular proximal and distal ends are exchanged. The Vph1 proximal-Stv1 distal (VPSD) aNT chimera binds to the glucose-responsive RAVE assembly factor in vitro but exhibits little binding to PI(3,5)P2. The Stv1 proximal-Vph1 distal (SPVD) aNT lacks RAVE binding but binds more tightly to phosphoinositides than Vph1 or Stv1. When attached to the Vph1 C-terminal domain in vivo, both chimeras complement growth defects of a vph1∆ mutant, but only the SPVD chimera exhibits wild-type V-ATPase activity. Cells containing the SPVD chimera adapt more slowly to a poor carbon source than wild-type cells but grow more rapidly than wild-type cells after a shift to alkaline pH. This is the first example of a "redesigned" V-ATPase with altered regulatory properties and adaptation to specific stresses.
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Affiliation(s)
- Farzana Tuli
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210
| | - Patricia M Kane
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210
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27
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Structural and Functional Diversity of Two ATP-Driven Plant Proton Pumps. Int J Mol Sci 2023; 24:ijms24054512. [PMID: 36901943 PMCID: PMC10003446 DOI: 10.3390/ijms24054512] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/09/2023] [Accepted: 02/22/2023] [Indexed: 03/02/2023] Open
Abstract
Two ATP-dependent proton pumps function in plant cells. Plasma membrane H+-ATPase (PM H+-ATPase) transfers protons from the cytoplasm to the apoplast, while vacuolar H+-ATPase (V-ATPase), located in tonoplasts and other endomembranes, is responsible for proton pumping into the organelle lumen. Both enzymes belong to two different families of proteins and, therefore, differ significantly in their structure and mechanism of action. The plasma membrane H+-ATPase is a member of the P-ATPases that undergo conformational changes, associated with two distinct E1 and E2 states, and autophosphorylation during the catalytic cycle. The vacuolar H+-ATPase represents rotary enzymes functioning as a molecular motor. The plant V-ATPase consists of thirteen different subunits organized into two subcomplexes, the peripheral V1 and the membrane-embedded V0, in which the stator and rotor parts have been distinguished. In contrast, the plant plasma membrane proton pump is a functional single polypeptide chain. However, when the enzyme is active, it transforms into a large twelve-protein complex of six H+-ATPase molecules and six 14-3-3 proteins. Despite these differences, both proton pumps can be regulated by the same mechanisms (such as reversible phosphorylation) and, in some processes, such as cytosolic pH regulation, may act in a coordinated way.
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28
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Ngo C, Ekanayake A, Zhang C. Identification of Covalent Ligands – from Single Targets to Whole Proteome. Isr J Chem 2023. [DOI: 10.1002/ijch.202200105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Chau Ngo
- Department of Chemistry Loker Hydrocarbon Research Institute University of Southern California 90089 Los Angeles California USA
| | - Arunika Ekanayake
- Department of Chemistry Loker Hydrocarbon Research Institute University of Southern California 90089 Los Angeles California USA
- Current address: Department of Chemistry University of Alberta T6G 2G2 Edmonton AB Canada
| | - Chao Zhang
- Department of Chemistry Loker Hydrocarbon Research Institute University of Southern California 90089 Los Angeles California USA
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29
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Yokoyama K. Rotary mechanism of V/A-ATPases-how is ATP hydrolysis converted into a mechanical step rotation in rotary ATPases? Front Mol Biosci 2023; 10:1176114. [PMID: 37168257 PMCID: PMC10166205 DOI: 10.3389/fmolb.2023.1176114] [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: 02/28/2023] [Accepted: 04/13/2023] [Indexed: 05/13/2023] Open
Abstract
V/A-ATPase is a rotary molecular motor protein that produces ATP through the rotation of its central rotor. The soluble part of this protein, the V1 domain, rotates upon ATP hydrolysis. However, the mechanism by which ATP hydrolysis in the V1 domain couples with the mechanical rotation of the rotor is still unclear. Cryo-EM snapshot analysis of V/A-ATPase indicated that three independent and simultaneous catalytic events occurred at the three catalytic dimers (ABopen, ABsemi, and ABclosed), leading to a 120° rotation of the central rotor. Besides the closing motion caused by ATP bound to ABopen, the hydrolysis of ATP bound to ABsemi drives the 120° step. Our recent time-resolved cryo-EM snapshot analysis provides further evidence for this model. This review aimed to provide a comprehensive overview of the structure and function of V/A-ATPase from a thermophilic bacterium, one of the most well-studied rotary ATPases to date.
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30
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DiIorio MC, Kulczyk AW. Exploring the Structural Variability of Dynamic Biological Complexes by Single-Particle Cryo-Electron Microscopy. MICROMACHINES 2022; 14:mi14010118. [PMID: 36677177 PMCID: PMC9866264 DOI: 10.3390/mi14010118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 12/27/2022] [Accepted: 12/30/2022] [Indexed: 05/15/2023]
Abstract
Biological macromolecules and assemblies precisely rearrange their atomic 3D structures to execute cellular functions. Understanding the mechanisms by which these molecular machines operate requires insight into the ensemble of structural states they occupy during the functional cycle. Single-particle cryo-electron microscopy (cryo-EM) has become the preferred method to provide near-atomic resolution, structural information about dynamic biological macromolecules elusive to other structure determination methods. Recent advances in cryo-EM methodology have allowed structural biologists not only to probe the structural intermediates of biochemical reactions, but also to resolve different compositional and conformational states present within the same dataset. This article reviews newly developed sample preparation and single-particle analysis (SPA) techniques for high-resolution structure determination of intrinsically dynamic and heterogeneous samples, shedding light upon the intricate mechanisms employed by molecular machines and helping to guide drug discovery efforts.
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Affiliation(s)
- Megan C. DiIorio
- Institute for Quantitative Biomedicine, Rutgers University, 174 Frelinghuysen Road, Piscataway, NJ 08854, USA
| | - Arkadiusz W. Kulczyk
- Institute for Quantitative Biomedicine, Rutgers University, 174 Frelinghuysen Road, Piscataway, NJ 08854, USA
- Department of Biochemistry and Microbiology, Rutgers University, 75 Lipman Drive, New Brunswick, NJ 08901, USA
- Correspondence:
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31
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Genovese I, Fornetti E, Ruocco G. Mitochondria inter-organelle relationships in cancer protein aggregation. Front Cell Dev Biol 2022; 10:1062993. [PMID: 36601538 PMCID: PMC9806238 DOI: 10.3389/fcell.2022.1062993] [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: 10/06/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
Mitochondria are physically associated with other organelles, such as ER and lysosomes, forming a complex network that is crucial for cell homeostasis regulation. Inter-organelle relationships are finely regulated by both tether systems, which maintain physical proximity, and by signaling cues that induce the exchange of molecular information to regulate metabolism, Ca2+ homeostasis, redox state, nutrient availability, and proteostasis. The coordinated action of the organelles is engaged in the cellular integrated stress response. In any case, pathological conditions alter functional communication and efficient rescue pathway activation, leading to cell distress exacerbation and eventually cell death. Among these detrimental signals, misfolded protein accumulation and aggregation cause major damage to the cells, since defects in protein clearance systems worsen cell toxicity. A cause for protein aggregation is often a defective mitochondrial redox balance, and the ER freshly translated misfolded proteins and/or a deficient lysosome-mediated clearance system. All these features aggravate mitochondrial damage and enhance proteotoxic stress. This review aims to gather the current knowledge about the complex liaison between mitochondria, ER, and lysosomes in facing proteotoxic stress and protein aggregation, highlighting both causes and consequences. Particularly, specific focus will be pointed to cancer, a pathology in which inter-organelle relations in protein aggregation have been poorly investigated.
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Affiliation(s)
- Ilaria Genovese
- Center for Life Nano and Neuro Science, Istituto Italiano di Tecnologia (IIT), Rome, Italy,*Correspondence: Ilaria Genovese,
| | - Ersilia Fornetti
- Center for Life Nano and Neuro Science, Istituto Italiano di Tecnologia (IIT), Rome, Italy
| | - Giancarlo Ruocco
- Center for Life Nano and Neuro Science, Istituto Italiano di Tecnologia (IIT), Rome, Italy,Department of Physics, Sapienza University of Rome, Rome, Italy
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32
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Hertel A, Alves LM, Dutz H, Tascher G, Bonn F, Kaulich M, Dikic I, Eimer S, Steinberg F, Bremm A. USP32-regulated LAMTOR1 ubiquitination impacts mTORC1 activation and autophagy induction. Cell Rep 2022; 41:111653. [PMID: 36476874 DOI: 10.1016/j.celrep.2022.111653] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 08/16/2022] [Accepted: 10/20/2022] [Indexed: 12/12/2022] Open
Abstract
The endosomal-lysosomal system is a series of organelles in the endocytic pathway that executes trafficking and degradation of proteins and lipids and mediates the internalization of nutrients and growth factors to ensure cell survival, growth, and differentiation. Here, we reveal regulatory, non-proteolytic ubiquitin signals in this complex system that are controlled by the enigmatic deubiquitinase USP32. Knockout (KO) of USP32 in primary hTERT-RPE1 cells results among others in hyperubiquitination of the Ragulator complex subunit LAMTOR1. Accumulation of LAMTOR1 ubiquitination impairs its interaction with the vacuolar H+-ATPase, reduces Ragulator function, and ultimately limits mTORC1 recruitment. Consistently, in USP32 KO cells, less mTOR kinase localizes to lysosomes, mTORC1 activity is decreased, and autophagy is induced. Furthermore, we demonstrate that depletion of USP32 homolog CYK-3 in Caenorhabditis elegans results in mTOR inhibition and autophagy induction. In summary, we identify a control mechanism of the mTORC1 activation cascade at lysosomes via USP32-regulated LAMTOR1 ubiquitination.
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Affiliation(s)
- Alexandra Hertel
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Ludovico Martins Alves
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Henrik Dutz
- Center for Biological Systems Analysis, University of Freiburg, Habsburgerstr. 49, 79104 Freiburg, Germany
| | - Georg Tascher
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Florian Bonn
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Manuel Kaulich
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Frankfurt Cancer Institute, 60596 Frankfurt am Main, Germany; Cardio-Pulmonary Institute, 60590 Frankfurt am Main, Germany
| | - Ivan Dikic
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany; Frankfurt Cancer Institute, 60596 Frankfurt am Main, Germany; Cardio-Pulmonary Institute, 60590 Frankfurt am Main, Germany
| | - Stefan Eimer
- Institute of Cell Biology and Neuroscience, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60439 Frankfurt am Main, Germany
| | - Florian Steinberg
- Center for Biological Systems Analysis, University of Freiburg, Habsburgerstr. 49, 79104 Freiburg, Germany
| | - Anja Bremm
- Institute of Biochemistry II, Goethe University Frankfurt - Medical Faculty, University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
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33
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Tolani B, Celli A, Yao Y, Tan YZ, Fetter R, Liem CR, de Smith AJ, Vasanthakumar T, Bisignano P, Cotton AD, Seiple IB, Rubinstein JL, Jost M, Weissman JS. Ras-mutant cancers are sensitive to small molecule inhibition of V-type ATPases in mice. Nat Biotechnol 2022; 40:1834-1844. [PMID: 35879364 PMCID: PMC9750872 DOI: 10.1038/s41587-022-01386-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 06/03/2022] [Indexed: 01/14/2023]
Abstract
Mutations in Ras family proteins are implicated in 33% of human cancers, but direct pharmacological inhibition of Ras mutants remains challenging. As an alternative to direct inhibition, we screened for sensitivities in Ras-mutant cells and discovered 249C as a Ras-mutant selective cytotoxic agent with nanomolar potency against a spectrum of Ras-mutant cancers. 249C binds to vacuolar (V)-ATPase with nanomolar affinity and inhibits its activity, preventing lysosomal acidification and inhibiting autophagy and macropinocytosis pathways that several Ras-driven cancers rely on for survival. Unexpectedly, potency of 249C varies with the identity of the Ras driver mutation, with the highest potency for KRASG13D and G12V both in vitro and in vivo, highlighting a mutant-specific dependence on macropinocytosis and lysosomal pH. Indeed, 249C potently inhibits tumor growth without adverse side effects in mouse xenografts of KRAS-driven lung and colon cancers. A comparison of isogenic SW48 xenografts with different KRAS mutations confirmed that KRASG13D/+ (followed by G12V/+) mutations are especially sensitive to 249C treatment. These data establish proof-of-concept for targeting V-ATPase in cancers driven by specific KRAS mutations such as KRASG13D and G12V.
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Affiliation(s)
- Bhairavi Tolani
- Thoracic Oncology Program, Department of Surgery, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA.
| | - Anna Celli
- Laboratory for Cell Analysis Core Facility, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, USA
| | - Yanmin Yao
- Department of Pharmaceutical Chemistry and Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Yong Zi Tan
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Disease Intervention Technology Laboratory, Agency for Science, Technology and Research, Singapore, Singapore
| | - Richard Fetter
- Howard Hughes Medical Institute, Department of Biology, Stanford University, Stanford, CA, USA
| | - Christina R Liem
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
- Division of Biological Sciences, the Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA, USA
| | - Adam J de Smith
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA
| | - Thamiya Vasanthakumar
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON, Canada
| | - Paola Bisignano
- Department of Pharmaceutical Chemistry and Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Adam D Cotton
- Department of Pharmaceutical Chemistry and Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Ian B Seiple
- Department of Pharmaceutical Chemistry and Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - John L Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON, Canada
- Department of Medical Biophysics, The University of Toronto, Toronto, ON, Canada
| | - Marco Jost
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA.
- Department of Microbiology & Immunology, University of California, San Francisco, CA, USA.
- Department of Microbiology, Harvard Medical School, Boston, MA, USA.
| | - Jonathan S Weissman
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA, USA
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
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34
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Beton JG, Cragnolini T, Kaleel M, Mulvaney T, Sweeney A, Topf M. Integrating model simulation tools and
cryo‐electron
microscopy. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2022. [DOI: 10.1002/wcms.1642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Joseph George Beton
- Centre for Structural Systems Biology (CSSB) Leibniz‐Institut für Virologie (LIV) Hamburg Germany
| | - Tristan Cragnolini
- Institute of Structural and Molecular Biology, Birkbeck and University College London London UK
| | - Manaz Kaleel
- Centre for Structural Systems Biology (CSSB) Leibniz‐Institut für Virologie (LIV) Hamburg Germany
| | - Thomas Mulvaney
- Centre for Structural Systems Biology (CSSB) Leibniz‐Institut für Virologie (LIV) Hamburg Germany
| | - Aaron Sweeney
- Centre for Structural Systems Biology (CSSB) Leibniz‐Institut für Virologie (LIV) Hamburg Germany
| | - Maya Topf
- Centre for Structural Systems Biology (CSSB) Leibniz‐Institut für Virologie (LIV) Hamburg Germany
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Kosmidis E, Shuttle CG, Preobraschenski J, Ganzella M, Johnson PJ, Veshaguri S, Holmkvist J, Møller MP, Marantos O, Marcoline F, Grabe M, Pedersen JL, Jahn R, Stamou D. Regulation of the mammalian-brain V-ATPase through ultraslow mode-switching. Nature 2022; 611:827-834. [PMID: 36418452 PMCID: PMC11212661 DOI: 10.1038/s41586-022-05472-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 10/21/2022] [Indexed: 11/24/2022]
Abstract
Vacuolar-type adenosine triphosphatases (V-ATPases)1-3 are electrogenic rotary mechanoenzymes structurally related to F-type ATP synthases4,5. They hydrolyse ATP to establish electrochemical proton gradients for a plethora of cellular processes1,3. In neurons, the loading of all neurotransmitters into synaptic vesicles is energized by about one V-ATPase molecule per synaptic vesicle6,7. To shed light on this bona fide single-molecule biological process, we investigated electrogenic proton-pumping by single mammalian-brain V-ATPases in single synaptic vesicles. Here we show that V-ATPases do not pump continuously in time, as suggested by observing the rotation of bacterial homologues8 and assuming strict ATP-proton coupling. Instead, they stochastically switch between three ultralong-lived modes: proton-pumping, inactive and proton-leaky. Notably, direct observation of pumping revealed that physiologically relevant concentrations of ATP do not regulate the intrinsic pumping rate. ATP regulates V-ATPase activity through the switching probability of the proton-pumping mode. By contrast, electrochemical proton gradients regulate the pumping rate and the switching of the pumping and inactive modes. A direct consequence of mode-switching is all-or-none stochastic fluctuations in the electrochemical gradient of synaptic vesicles that would be expected to introduce stochasticity in proton-driven secondary active loading of neurotransmitters and may thus have important implications for neurotransmission. This work reveals and emphasizes the mechanistic and biological importance of ultraslow mode-switching.
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Affiliation(s)
- Eleftherios Kosmidis
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Christopher G Shuttle
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Julia Preobraschenski
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Institute for Auditory Neuroscience, University Medical Center, Göttingen, Germany
- Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany
| | - Marcelo Ganzella
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Peter J Johnson
- Department of Mathematical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Mathematics, University of Manchester, Manchester, UK
| | - Salome Veshaguri
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
- Novozymes A/S, Kgs Lyngby, Denmark
| | - Jesper Holmkvist
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Mads P Møller
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Orestis Marantos
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Frank Marcoline
- Cardiovascular Research Institute, Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, USA
| | - Michael Grabe
- Cardiovascular Research Institute, Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA, USA
| | - Jesper L Pedersen
- Department of Mathematical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Reinhard Jahn
- Laboratory of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Dimitrios Stamou
- Center for Geometrically Engineered Cellular Membranes, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark.
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36
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Transcriptome analysis of gills reveals novel insights into the molecular response of stinging catfish (Heteropneustes fossilis) to environmental hypertonicity. Gene 2022; 851:147044. [DOI: 10.1016/j.gene.2022.147044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/27/2022] [Accepted: 11/08/2022] [Indexed: 11/15/2022]
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37
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Tan YZ, Abbas YM, Wu JZ, Wu D, Keon KA, Hesketh GG, Bueler SA, Gingras AC, Robinson CV, Grinstein S, Rubinstein JL. CryoEM of endogenous mammalian V-ATPase interacting with the TLDc protein mEAK-7. Life Sci Alliance 2022; 5:e202201527. [PMID: 35794005 PMCID: PMC9263379 DOI: 10.26508/lsa.202201527] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/17/2022] [Accepted: 06/21/2022] [Indexed: 12/18/2022] Open
Abstract
V-ATPases are rotary proton pumps that serve as signaling hubs with numerous protein binding partners. CryoEM with exhaustive focused classification allowed detection of endogenous proteins associated with porcine kidney V-ATPase. An extra C subunit was found in ∼3% of complexes, whereas ∼1.6% of complexes bound mEAK-7, a protein with proposed roles in dauer formation in nematodes and mTOR signaling in mammals. High-resolution cryoEM of porcine kidney V-ATPase with recombinant mEAK-7 showed that mEAK-7's TLDc domain interacts with V-ATPase's stator, whereas its C-terminal α helix binds V-ATPase's rotor. This crosslink would be expected to inhibit rotary catalysis. However, unlike the yeast TLDc protein Oxr1p, exogenous mEAK-7 does not inhibit V-ATPase and mEAK-7 overexpression in cells does not alter lysosomal or phagosomal pH. Instead, cryoEM suggests that the mEAK-7:V-ATPase interaction is disrupted by ATP-induced rotation of the rotor. Comparison of Oxr1p and mEAK-7 binding explains this difference. These results show that V-ATPase binding by TLDc domain proteins can lead to effects ranging from strong inhibition to formation of labile interactions that are sensitive to the enzyme's activity.
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Affiliation(s)
- Yong Zi Tan
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, Canada
| | - Yazan M Abbas
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, Canada
| | - Jing Ze Wu
- Program in Cell Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Biochemistry, University of Toronto, Toronto, Canada
| | - Di Wu
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, UK
| | - Kristine A Keon
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, Canada
| | - Geoffrey G Hesketh
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Canada
| | - Stephanie A Bueler
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Carol V Robinson
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, UK
| | - Sergio Grinstein
- Program in Cell Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Biochemistry, University of Toronto, Toronto, Canada
| | - John L Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, Canada
- Department of Biochemistry, University of Toronto, Toronto, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
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38
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Identification of mEAK-7 as a human V-ATPase regulator via cryo-EM data mining. Proc Natl Acad Sci U S A 2022; 119:e2203742119. [PMID: 35994636 PMCID: PMC9436323 DOI: 10.1073/pnas.2203742119] [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] [Indexed: 11/18/2022] Open
Abstract
Vacuolar-type adenosine triphosphatases (V-ATPases) not only function as rotary proton pumps in cellular organelles but also serve as signaling hubs. To identify the endogenous binding partners of V-ATPase, we collected a large dataset of human V-ATPases and did extensive classification and focused refinement of human V-ATPases. Unexpectedly, about 17% of particles in state 2 of human V-ATPases display additional density with an overall resolution of 3.3 Å. Structural analysis combined with artificial intelligence modeling enables us to identify this additional density as mEAK-7, a protein involved in mechanistic target of rapamycin (mTOR) signaling in mammals. Our structure shows that mEAK-7 interacts with subunits A, B, D, and E of V-ATPases in state 2. Thus, we propose that mEAK-7 may regulate V-ATPase function through binding to V-ATPases in state 2 as well as mediate mTOR signaling.
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39
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Guerrini R, Mei D, Kerti-Szigeti K, Pepe S, Koenig MK, Von Allmen G, Cho MT, McDonald K, Baker J, Bhambhani V, Powis Z, Rodan L, Nabbout R, Barcia G, Rosenfeld JA, Bacino CA, Mignot C, Power LH, Harris CJ, Marjanovic D, Møller RS, Hammer TB, Keski Filppula R, Vieira P, Hildebrandt C, Sacharow S, Maragliano L, Benfenati F, Lachlan K, Benneche A, Petit F, de Sainte Agathe JM, Hallinan B, Si Y, Wentzensen IM, Zou F, Narayanan V, Matsumoto N, Boncristiano A, la Marca G, Kato M, Anderson K, Barba C, Sturiale L, Garozzo D, Bei R, Masuelli L, Conti V, Novarino G, Fassio A. Phenotypic and genetic spectrum of ATP6V1A encephalopathy: a disorder of lysosomal homeostasis. Brain 2022; 145:2687-2703. [PMID: 35675510 PMCID: PMC10893886 DOI: 10.1093/brain/awac145] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 04/04/2022] [Accepted: 04/07/2022] [Indexed: 11/30/2023] Open
Abstract
Vacuolar-type H+-ATPase (V-ATPase) is a multimeric complex present in a variety of cellular membranes that acts as an ATP-dependent proton pump and plays a key role in pH homeostasis and intracellular signalling pathways. In humans, 22 autosomal genes encode for a redundant set of subunits allowing the composition of diverse V-ATPase complexes with specific properties and expression. Sixteen subunits have been linked to human disease. Here we describe 26 patients harbouring 20 distinct pathogenic de novo missense ATP6V1A variants, mainly clustering within the ATP synthase α/β family-nucleotide-binding domain. At a mean age of 7 years (extremes: 6 weeks, youngest deceased patient to 22 years, oldest patient) clinical pictures included early lethal encephalopathies with rapidly progressive massive brain atrophy, severe developmental epileptic encephalopathies and static intellectual disability with epilepsy. The first clinical manifestation was early hypotonia, in 70%; 81% developed epilepsy, manifested as developmental epileptic encephalopathies in 58% of the cohort and with infantile spasms in 62%; 63% of developmental epileptic encephalopathies failed to achieve any developmental, communicative or motor skills. Less severe outcomes were observed in 23% of patients who, at a mean age of 10 years and 6 months, exhibited moderate intellectual disability, with independent walking and variable epilepsy. None of the patients developed communicative language. Microcephaly (38%) and amelogenesis imperfecta/enamel dysplasia (42%) were additional clinical features. Brain MRI demonstrated hypomyelination and generalized atrophy in 68%. Atrophy was progressive in all eight individuals undergoing repeated MRIs. Fibroblasts of two patients with developmental epileptic encephalopathies showed decreased LAMP1 expression, Lysotracker staining and increased organelle pH, consistent with lysosomal impairment and loss of V-ATPase function. Fibroblasts of two patients with milder disease, exhibited a different phenotype with increased Lysotracker staining, decreased organelle pH and no significant modification in LAMP1 expression. Quantification of substrates for lysosomal enzymes in cellular extracts from four patients revealed discrete accumulation. Transmission electron microscopy of fibroblasts of four patients with variable severity and of induced pluripotent stem cell-derived neurons from two patients with developmental epileptic encephalopathies showed electron-dense inclusions, lipid droplets, osmiophilic material and lamellated membrane structures resembling phospholipids. Quantitative assessment in induced pluripotent stem cell-derived neurons identified significantly smaller lysosomes. ATP6V1A-related encephalopathy represents a new paradigm among lysosomal disorders. It results from a dysfunctional endo-lysosomal membrane protein causing altered pH homeostasis. Its pathophysiology implies intracellular accumulation of substrates whose composition remains unclear, and a combination of developmental brain abnormalities and neurodegenerative changes established during prenatal and early postanal development, whose severity is variably determined by specific pathogenic variants.
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Affiliation(s)
- Renzo Guerrini
- Neuroscience Department, Children's Hospital Meyer, University of Florence, Florence, Italy
| | - Davide Mei
- Neuroscience Department, Children's Hospital Meyer, University of Florence, Florence, Italy
| | | | - Sara Pepe
- Department of Experimental Medicine, University of Genoa, Italy
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy
| | - Mary Kay Koenig
- Department of Pediatrics, Division of Child and Adolescent Neurology, The University of Texas McGovern Medical School, Houston, TX, USA
| | - Gretchen Von Allmen
- Department of Pediatrics, Division of Child and Adolescent Neurology, The University of Texas McGovern Medical School, Houston, TX, USA
| | | | - Kimberly McDonald
- Pediatric Neurology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Janice Baker
- Genetics and Genomics, Children's Minnesota, Minneapolis, MN, USA
| | - Vikas Bhambhani
- Genetics and Genomics, Children's Minnesota, Minneapolis, MN, USA
| | - Zöe Powis
- Ambry Genetics, Aliso Viejo, CA, USA
| | - Lance Rodan
- Division of Genetics and Genomics and Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Rima Nabbout
- Reference Centre for Rare Epilepsies, Department of Genetics, Necker Enfants Malades Hospital, APHP, member of ERN EpiCARE, Université de Paris, Paris, France
| | - Giulia Barcia
- Reference Centre for Rare Epilepsies, Department of Genetics, Necker Enfants Malades Hospital, APHP, member of ERN EpiCARE, Université de Paris, Paris, France
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Carlos A Bacino
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Cyril Mignot
- APHP, Sorbonne Université, Départément de Génétique, Centre de Référence Déficiences Intellectuelles de Causes Rares, Paris, France
- Institut du Cerveau (ICM), UMR S 1127, Inserm U1127, CNRS UMR 7225, Sorbonne Université, 75013 Paris, France
| | - Lillian H Power
- Pediatric Neurology, Stead Family Department of Pediatrics, University of Iowa Stead Family Children’s Hospital, Iowa City, IA, USA
| | - Catharine J Harris
- Department of Pediatric Genetics, University of Missouri Medical Center, Columbia, MO 65212, USA
| | - Dragan Marjanovic
- Danish Epilepsy Centre Filadelfia, Adult Neurology, Dianalund, Denmark
| | - Rikke S Møller
- Department of Epilepsy Genetics and Personalized Treatment, Danish Epilepsy Center Filadelfia, Dianalund, Denmark
- Department of Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Trine B Hammer
- Department of Epilepsy Genetics and Personalized Treatment, Danish Epilepsy Center Filadelfia, Dianalund, Denmark
| | - The DDD Study
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, UK
| | - Riikka Keski Filppula
- Department of Clinical Genetics, Oulu University Hospital, Medical Research Center Oulu and PEDEGO Research Unit, University of Oulu, Oulu, Finland
| | - Päivi Vieira
- Clinic for Children and Adolescents, Oulu University Hospital, Medical Research Center Oulu and PEDEGO Research Unit, University of Oulu, Oulu, Finland
| | - Clara Hildebrandt
- Division of Genetics and Genomics, Metabolism Program, Boston Children's Hospital, Boston, MA, USA
| | | | | | - Luca Maragliano
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | - Katherine Lachlan
- Wessex Clinical Genetics Service, University Hospital Southampton NHS Foundation Trust, Southampton, UK
- Human Development and Health, Faculty of Medicine University of Southampton, Southampton, UK
| | - Andreas Benneche
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
| | | | - Jean Madeleine de Sainte Agathe
- Laboratoire de Biologie Médicale Multi Sites SeqOIA, Laboratoire de Médecine Génomique, APHP. Sorbonne Université, Paris, France
| | - Barbara Hallinan
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Division of Child Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Yue Si
- GeneDx, Gaithersburg, MD 20877, USA
| | | | | | - Vinodh Narayanan
- Neurogenomics Division, Center for Rare Childhood Disorders, Translational Genomics Research Institute (TGen), Phoenix, AZ 85012, USA
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | | | - Giancarlo la Marca
- Newborn Screening, Clinical Chemistry and Pharmacology Laboratory, Meyer Children’s University Hospital, Florence, Italy
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Mitsuhiro Kato
- Department of Pediatrics, Showa University School of Medicine and Epilepsy Medical Center, Showa University Hospital, Tokyo, Japan
| | | | - Carmen Barba
- Neuroscience Department, Children's Hospital Meyer, University of Florence, Florence, Italy
| | - Luisa Sturiale
- CNR, Institute for Polymers, Composites and Biomaterials, IPCB, 95126 Catania, Italy
| | - Domenico Garozzo
- CNR, Institute for Polymers, Composites and Biomaterials, IPCB, 95126 Catania, Italy
| | - Roberto Bei
- Department of Clinical Sciences and Translational Medicine, University of Rome ‘Tor Vergata', Rome, Italy
| | | | - Laura Masuelli
- Department of Experimental Medicine, University of Rome ‘Sapienza', Rome, Italy
| | - Valerio Conti
- Neuroscience Department, Children's Hospital Meyer, University of Florence, Florence, Italy
| | - Gaia Novarino
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Anna Fassio
- Department of Experimental Medicine, University of Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
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40
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Structure of V-ATPase from citrus fruit. Structure 2022; 30:1403-1410.e4. [PMID: 36041457 DOI: 10.1016/j.str.2022.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/14/2022] [Accepted: 07/18/2022] [Indexed: 11/23/2022]
Abstract
We used the Legionella pneumophila effector SidK to affinity purify the endogenous vacuolar-type ATPases (V-ATPases) from lemon fruit. The preparation was sufficient for cryoelectron microscopy, allowing structure determination of the enzyme in two rotational states. The structure defines the ATP:H+ ratio of the enzyme, demonstrating that it can establish a maximum ΔpH of ∼3, which is insufficient to maintain the low pH observed in the vacuoles of juice sac cells in lemons and other citrus fruit. Compared with yeast and mammalian enzymes, the membrane region of the plant V-ATPase lacks subunit f and possesses an unusual configuration of transmembrane α helices. Subunit H, which inhibits ATP hydrolysis in the isolated catalytic region of V-ATPase, adopts two different conformations in the intact complex, hinting at a role in modulating activity in the intact enzyme.
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41
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Gerle C, Kishikawa JI, Yamaguchi T, Nakanishi A, Çoruh O, Makino F, Miyata T, Kawamoto A, Yokoyama K, Namba K, Kurisu G, Kato T. Structures of Multisubunit Membrane Complexes With the CRYO ARM 200. Microscopy (Oxf) 2022; 71:249-261. [PMID: 35861182 PMCID: PMC9535789 DOI: 10.1093/jmicro/dfac037] [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: 04/25/2022] [Revised: 07/18/2022] [Accepted: 07/20/2022] [Indexed: 11/18/2022] Open
Abstract
Progress in structural membrane biology has been significantly accelerated by the ongoing ‘Resolution Revolution’ in cryo-electron microscopy (cryo-EM). In particular, structure determination by single-particle analysis has evolved into the most powerful method for atomic model building of multisubunit membrane protein complexes. This has created an ever-increasing demand in cryo-EM machine time, which to satisfy is in need of new and affordable cryo-electron microscopes. Here, we review our experience in using the JEOL CRYO ARM 200 prototype for the structure determination by single-particle analysis of three different multisubunit membrane complexes: the Thermus thermophilus V-type ATPase VO complex, the Thermosynechococcus elongatus photosystem I monomer and the flagellar motor lipopolysaccharide peptidoglycan ring (LP ring) from Salmonella enterica.
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Affiliation(s)
- Christoph Gerle
- Institute for Protein Research, Osaka University, 3-2 Yamada Oka, Suita, Osaka 565-0871, Japan.,RIKEN SPring-8 Center, Life Science Research Infrastructure Group, Sayo-gun, Hyogo 679-5148, Japan
| | - Jun-Ichi Kishikawa
- Institute for Protein Research, Osaka University, 3-2 Yamada Oka, Suita, Osaka 565-0871, Japan
| | - Tomoko Yamaguchi
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Atsuko Nakanishi
- Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto, Japan.,Research Center for Ultra-High Voltage Electron Microscopy, Osaka, University, Ibaraki, Osaka 567-0047, Japan
| | - Orkun Çoruh
- Institute for Protein Research, Osaka University, 3-2 Yamada Oka, Suita, Osaka 565-0871, Japan.,Institute of Science and Technology Austria, Klosterneuburg, 3400 Austria
| | - Fumiaki Makino
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan.,JEOL Ltd., Akishima, Tokyo, Japan
| | - Tomoko Miyata
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Akihiro Kawamoto
- Institute for Protein Research, Osaka University, 3-2 Yamada Oka, Suita, Osaka 565-0871, Japan
| | - Ken Yokoyama
- Department of Molecular Biosciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto, Japan
| | - Keiichi Namba
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan.,RIKEN Center for Biosystems Dynamics Research, Suita, Osaka, Japan.,JEOL YOKOGUSHI Research Alliance Laboratories, Osaka University, Suita, Osaka, Japan
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, 3-2 Yamada Oka, Suita, Osaka 565-0871, Japan
| | - Takayuki Kato
- Institute for Protein Research, Osaka University, 3-2 Yamada Oka, Suita, Osaka 565-0871, Japan.,Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
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42
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Kandel Y, Pinch M, Lamsal M, Martinez N, Hansen IA. Exploratory phosphoproteomics profiling of Aedes aegypti Malpighian tubules during blood meal processing reveals dramatic transition in function. PLoS One 2022; 17:e0271248. [PMID: 35802606 PMCID: PMC9269769 DOI: 10.1371/journal.pone.0271248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 06/24/2022] [Indexed: 11/20/2022] Open
Abstract
Malpighian tubules, the renal organs of mosquitoes, facilitate the rapid dehydration of blood meals through aquaporin-mediated osmosis. We performed phosphoproteomics analysis of three Malpighian tubule protein-libraries (1000 tubules/sample) from unfed female mosquitoes as well as one and 24 hours after a blood meal. We identified 4663 putative phosphorylation sites in 1955 different proteins. Our exploratory dataset reveals blood meal-induced changes in phosphorylation patterns in many subunits of V-ATPase, proteins of the target of rapamycin signaling pathway, vesicle-mediated protein transport proteins, proteins involved in monocarboxylate transport, and aquaporins. Our phosphoproteomics data suggest the involvement of a variety of new pathways including nutrient-signaling, membrane protein shuttling, and paracellular water flow in the regulation of urine excretion. Our results support a model in which aquaporin channels translocate from intracellular vesicles to the cell membrane of stellate cells and the brush border membrane of principal cells upon blood feeding.
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Affiliation(s)
- Yashoda Kandel
- Department of Biology, New Mexico State University, Las Cruces, New Mexico, United States of America
| | - Matthew Pinch
- Department of Biology, New Mexico State University, Las Cruces, New Mexico, United States of America
| | - Mahesh Lamsal
- Department of Biology, New Mexico State University, Las Cruces, New Mexico, United States of America
| | - Nathan Martinez
- Department of Biology, New Mexico State University, Las Cruces, New Mexico, United States of America
| | - Immo A. Hansen
- Department of Biology, New Mexico State University, Las Cruces, New Mexico, United States of America
- Institute of Applied Biosciences, New Mexico State University, Las Cruces, New Mexico, United States of America
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43
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Seidel T. The Plant V-ATPase. FRONTIERS IN PLANT SCIENCE 2022; 13:931777. [PMID: 35845650 PMCID: PMC9280200 DOI: 10.3389/fpls.2022.931777] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/03/2022] [Indexed: 05/25/2023]
Abstract
V-ATPase is the dominant proton pump in plant cells. It contributes to cytosolic pH homeostasis and energizes transport processes across endomembranes of the secretory pathway. Its localization in the trans Golgi network/early endosomes is essential for vesicle transport, for instance for the delivery of cell wall components. Furthermore, it is crucial for response to abiotic and biotic stresses. The V-ATPase's rather complex structure and multiple subunit isoforms enable high structural flexibility with respect to requirements for different organs, developmental stages, and organelles. This complexity further demands a sophisticated assembly machinery and transport routes in cells, a process that is still not fully understood. Regulation of V-ATPase is a target of phosphorylation and redox-modifications but also involves interactions with regulatory proteins like 14-3-3 proteins and the lipid environment. Regulation by reversible assembly, as reported for yeast and the mammalian enzyme, has not be proven in plants but seems to be absent in autotrophic cells. Addressing the regulation of V-ATPase is a promising approach to adjust its activity for improved stress resistance or higher crop yield.
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44
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Courbon GM, Rubinstein JL. CryoEM Reveals the Complexity and Diversity of ATP Synthases. Front Microbiol 2022; 13:864006. [PMID: 35783400 PMCID: PMC9244403 DOI: 10.3389/fmicb.2022.864006] [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: 01/27/2022] [Accepted: 03/30/2022] [Indexed: 11/14/2022] Open
Abstract
During respiration, adenosine triphosphate (ATP) synthases harness the electrochemical proton motive force (PMF) generated by the electron transport chain (ETC) to synthesize ATP. These macromolecular machines operate by a remarkable rotary catalytic mechanism that couples transmembrane proton translocation to rotation of a rotor subcomplex, and rotation to ATP synthesis. Initially, x-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cross-linking were the only ways to gain insights into the three-dimensional (3D) structures of ATP synthases and, in particular, provided ground-breaking insights into the soluble parts of the complex that explained the catalytic mechanism by which rotation is coupled to ATP synthesis. In contrast, early electron microscopy was limited to studying the overall shape of the assembly. However, advances in electron cryomicroscopy (cryoEM) have allowed determination of high-resolution structures, including the membrane regions of ATP synthases. These studies revealed the high-resolution structures of the remaining ATP synthase subunits and showed how these subunits work together in the intact macromolecular machine. CryoEM continues to uncover the diversity of ATP synthase structures across species and has begun to show how ATP synthases can be targeted by therapies to treat human diseases.
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Affiliation(s)
- Gautier M. Courbon
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Medical Biophysics, The University of Toronto, Toronto, ON, Canada
| | - John L. Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Medical Biophysics, The University of Toronto, Toronto, ON, Canada
- Department of Biochemistry, The University of Toronto, Toronto, ON, Canada
- *Correspondence: John L. Rubinstein
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Wang R, Qin Y, Xie XS, Li X. Molecular basis of mEAK7-mediated human V-ATPase regulation. Nat Commun 2022; 13:3272. [PMID: 35672408 PMCID: PMC9174246 DOI: 10.1038/s41467-022-30899-z] [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: 12/29/2021] [Accepted: 05/24/2022] [Indexed: 11/09/2022] Open
Abstract
The activity of V-ATPase is well-known to be regulated by reversible dissociation of its V1 and Vo domains in response to growth factor stimulation, nutrient sensing, and cellular differentiation. The molecular basis of its regulation by an endogenous modulator without affecting V-ATPase assembly remains unclear. Here, we discover that a lysosome-anchored protein termed (mammalian Enhancer-of-Akt-1-7 (mEAK7)) binds to intact V-ATPase. We determine cryo-EM structure of human mEAK7 in complex with human V-ATPase in native lipid-containing nanodiscs. The structure reveals that the TLDc domain of mEAK7 engages with subunits A, B, and E, while its C-terminal domain binds to subunit D, presumably blocking V1-Vo torque transmission. Our functional studies suggest that mEAK7, which may act as a V-ATPase inhibitor, does not affect the activity of V-ATPase in vitro. However, overexpression of mEAK7 in HCT116 cells that stably express subunit a4 of V-ATPase represses the phosphorylation of ribosomal protein S6. Thus, this finding suggests that mEAK7 potentially links mTOR signaling with V-ATPase activity.
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Affiliation(s)
- Rong Wang
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Yu Qin
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Xiao-Song Xie
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Xiaochun Li
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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Zhou X, Zhao S, Liu T, Yao L, Zhao M, Ye X, Zhang X, Guo Q, Tu P, Zeng K. Schisandrol A protects AGEs-induced neuronal cells death by allosterically targeting ATP6V0d1 subunit of V-ATPase. Acta Pharm Sin B 2022; 12:3843-3860. [PMID: 36213534 PMCID: PMC9532558 DOI: 10.1016/j.apsb.2022.06.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 04/30/2022] [Accepted: 05/24/2022] [Indexed: 12/26/2022] Open
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Vasanthakumar T, Keon KA, Bueler SA, Jaskolka MC, Rubinstein JL. Coordinated conformational changes in the V 1 complex during V-ATPase reversible dissociation. Nat Struct Mol Biol 2022; 29:430-439. [PMID: 35469063 DOI: 10.1038/s41594-022-00757-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/03/2022] [Indexed: 11/10/2022]
Abstract
Vacuolar-type ATPases (V-ATPases) are rotary enzymes that acidify intracellular compartments in eukaryotic cells. These multi-subunit complexes consist of a cytoplasmic V1 region that hydrolyzes ATP and a membrane-embedded VO region that transports protons. V-ATPase activity is regulated by reversible dissociation of the two regions, with the isolated V1 and VO complexes becoming autoinhibited on disassembly and subunit C subsequently detaching from V1. In yeast, assembly of the V1 and VO regions is mediated by the regulator of the ATPase of vacuoles and endosomes (RAVE) complex through an unknown mechanism. We used cryogenic-electron microscopy of yeast V-ATPase to determine structures of the intact enzyme, the dissociated but complete V1 complex and the V1 complex lacking subunit C. On separation, V1 undergoes a dramatic conformational rearrangement, with its rotational state becoming incompatible for reassembly with VO. Loss of subunit C allows V1 to match the rotational state of VO, suggesting how RAVE could reassemble V1 and VO by recruiting subunit C.
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Affiliation(s)
- Thamiya Vasanthakumar
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Biochemistry, The University of Toronto, Toronto, Ontario, Canada
| | - Kristine A Keon
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Medical Biophysics, The University of Toronto, Toronto, Ontario, Canada
| | - Stephanie A Bueler
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Michael C Jaskolka
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, USA
| | - John L Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada. .,Department of Biochemistry, The University of Toronto, Toronto, Ontario, Canada. .,Department of Medical Biophysics, The University of Toronto, Toronto, Ontario, Canada.
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Zeng J, Kang WN, Jin L, Anjum AA, Li GQ. Vacuolar ATPase subunit F is critical for larval survival in Henosepilachna vigintioctopunctata. INSECT MOLECULAR BIOLOGY 2022; 31:177-189. [PMID: 34787941 DOI: 10.1111/imb.12749] [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: 01/11/2021] [Revised: 11/02/2021] [Accepted: 11/10/2021] [Indexed: 06/13/2023]
Abstract
Vacuolar ATPase (vATPase) is an important proton pump in insect tissues including gut and Malpighian tubule. Subunit F, one of the 16 subunits of the vATPase holoenzyme, is not well characterized. Here, we found that two HvvATPaseF isoforms were highly expressed in the hindgut and Malpighian tubules (MT) in the 28-spotted lady-beetle Henosepilachna vigintioctopunctata, an agricultural pest that feeds on Solanaceae and Cucurbitaceae. Knockdown of both HvvATPaseF variants by RNA interference (RNAi) delayed larval growth and negatively affected ecdysis and adult emergence. In the midgut, RNAi treatment resulted in the disappearance of peritrophic membrane, the reduction in the size and the impaired integrity of the gut, which was associated with sparse principle cells and an increase in TUNEL- and EdU-positive cells. Whereas the MT were opaque and the tubule lumens were full of urine in dsegfp-fed larvae, the tubules were clear and the tubule lumens were empty in the dsvATPaseF-fed larvae. HvvATPaseF knockdown was also associated with a decrease in the abundance of the fat body and the levels of glucose, trehalose, triglyceride, total soluble amino acids and proteins, and an increase in glycogen. Consistent with the known effects of sugars on chitin formation, both the expression level of a chitin biosynthesis gene and the thickness of the head capsule cuticle were reduced in the HvvATPaseF-depleted beetles. Our results demonstrated that subunit F plays an essential role in H. vigintioctopunctata development.
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Affiliation(s)
- Jie Zeng
- Agriculture Ministry Key Laboratory of Integrated Pest Management on Crops in East China/State and Local Joint Engineering Research Center of Green Pesticide Invention and Application, Department of Entomology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Wei-Nan Kang
- Agriculture Ministry Key Laboratory of Integrated Pest Management on Crops in East China/State and Local Joint Engineering Research Center of Green Pesticide Invention and Application, Department of Entomology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Lin Jin
- Agriculture Ministry Key Laboratory of Integrated Pest Management on Crops in East China/State and Local Joint Engineering Research Center of Green Pesticide Invention and Application, Department of Entomology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Ahmad Ali Anjum
- Agriculture Ministry Key Laboratory of Integrated Pest Management on Crops in East China/State and Local Joint Engineering Research Center of Green Pesticide Invention and Application, Department of Entomology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Guo-Qing Li
- Agriculture Ministry Key Laboratory of Integrated Pest Management on Crops in East China/State and Local Joint Engineering Research Center of Green Pesticide Invention and Application, Department of Entomology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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Bock LV, Grubmüller H. Effects of cryo-EM cooling on structural ensembles. Nat Commun 2022; 13:1709. [PMID: 35361752 PMCID: PMC8971465 DOI: 10.1038/s41467-022-29332-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 03/10/2022] [Indexed: 01/01/2023] Open
Abstract
Structure determination by cryo electron microscopy (cryo-EM) provides information on structural heterogeneity and ensembles at atomic resolution. To obtain cryo-EM images of macromolecules, the samples are first rapidly cooled down to cryogenic temperatures. To what extent the structural ensemble is perturbed during cooling is currently unknown. Here, to quantify the effects of cooling, we combined continuum model calculations of the temperature drop, molecular dynamics simulations of a ribosome complex before and during cooling with kinetic models. Our results suggest that three effects markedly contribute to the narrowing of the structural ensembles: thermal contraction, reduced thermal motion within local potential wells, and the equilibration into lower free-energy conformations by overcoming separating free-energy barriers. During cooling, barrier heights below 10 kJ/mol were found to be overcome, which is expected to reduce B-factors in ensembles imaged by cryo-EM. Our approach now enables the quantification of the heterogeneity of room-temperature ensembles from cryo-EM structures. The rapid temperature drop during plunge-freezing affects the structural ensembles obtained by cryo-EM. To quantify the extent of perturbation, Bock and Grubmüller combined continuum calculations, MD simulations, and kinetic models.
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Affiliation(s)
- Lars V Bock
- Theoretical and Computational Biophysics Department, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
| | - Helmut Grubmüller
- Theoretical and Computational Biophysics Department, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
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Keon KA, Benlekbir S, Kirsch SH, Müller R, Rubinstein JL. Cryo-EM of the Yeast V O Complex Reveals Distinct Binding Sites for Macrolide V-ATPase Inhibitors. ACS Chem Biol 2022; 17:619-628. [PMID: 35148071 DOI: 10.1021/acschembio.1c00894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Vacuolar-type adenosine triphosphatases (V-ATPases) are proton pumps found in almost all eukaryotic cells. These enzymes consist of a soluble catalytic V1 region that hydrolyzes ATP and a membrane-embedded VO region responsible for proton translocation. V-ATPase activity leads to acidification of endosomes, phagosomes, lysosomes, secretory vesicles, and the trans-Golgi network, with extracellular acidification occurring in some specialized cells. Small-molecule inhibitors of V-ATPase have played a crucial role in elucidating numerous aspects of cell biology by blocking acidification of intracellular compartments, while therapeutic use of V-ATPase inhibitors has been proposed for the treatment of cancer, osteoporosis, and some infections. Here, we determine structures of the isolated VO complex from Saccharomyces cerevisiae bound to two well-known macrolide inhibitors: bafilomycin A1 and archazolid A. The structures reveal different binding sites for the inhibitors on the surface of the proton-carrying c ring, with only a small amount of overlap between the two sites. Binding of both inhibitors is mediated primarily through van der Waals interactions in shallow pockets and suggests that the inhibitors block rotation of the ring. Together, these structures indicate the existence of a large chemical space available for V-ATPase inhibitors that block acidification by binding the c ring.
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Affiliation(s)
- Kristine A. Keon
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Canada M5G0A4
- Department of Medical Biophysics, The University of Toronto, Toronto, Canada M5G1L7
| | - Samir Benlekbir
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Canada M5G0A4
| | - Susanne H. Kirsch
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University Campus, 66123 Saarbrücken, Germany
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmacy, Saarland University Campus, 66123 Saarbrücken, Germany
| | - John L. Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Canada M5G0A4
- Department of Medical Biophysics, The University of Toronto, Toronto, Canada M5G1L7
- Department of Biochemistry, The University of Toronto, Toronto, Canada M5S1A8
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