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Guo P, Li B, Dong W, Zhou H, Wang L, Su T, Carl C, Zheng Y, Hong Y, Deng H, Pan D. PI4P-mediated solid-like Merlin condensates orchestrate Hippo pathway regulation. Science 2024; 385:eadf4478. [PMID: 39116228 DOI: 10.1126/science.adf4478] [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: 10/25/2022] [Revised: 10/11/2023] [Accepted: 06/10/2024] [Indexed: 08/10/2024]
Abstract
Despite recent studies implicating liquid-like biomolecular condensates in diverse cellular processes, many biomolecular condensates exist in a solid-like state, and their function and regulation are less understood. We show that the tumor suppressor Merlin, an upstream regulator of the Hippo pathway, localizes to both cell junctions and medial apical cortex in Drosophila epithelia, with the latter forming solid-like condensates that activate Hippo signaling. Merlin condensation required phosphatidylinositol-4-phosphate (PI4P)-mediated plasma membrane targeting and was antagonistically controlled by Pez and cytoskeletal tension through plasma membrane PI4P regulation. The solid-like material properties of Merlin condensates are essential for physiological function and protect the condensates against external perturbations. Collectively, these findings uncover an essential role for solid-like condensates in normal physiology and reveal regulatory mechanisms for their formation and disassembly.
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Affiliation(s)
- Pengfei Guo
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Bing Li
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Wei Dong
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Huabin Zhou
- Department of Biophysics, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Li Wang
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ting Su
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Christopher Carl
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yonggang Zheng
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yang Hong
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Hua Deng
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Duojia Pan
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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2
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Tran CS, Kersten J, Yan J, Breinig M, Huth T, Poth T, Colasanti O, Riedl T, Faure-Dupuy S, Diehl S, Verhoye L, Li TF, Lingemann M, Schult P, Ahlén G, Frelin L, Kühnel F, Vondran FWR, Breuhahn K, Meuleman P, Heikenwälder M, Schirmacher P, Bartenschlager R, Laketa V, Roessler S, Tschaharganeh DF, Sällberg M, Lohmann V. Phosphatidylinositol 4-Kinase III Alpha Governs Cytoskeletal Organization for Invasiveness of Liver Cancer Cells. Gastroenterology 2024; 167:522-537. [PMID: 38636680 DOI: 10.1053/j.gastro.2024.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 03/06/2024] [Accepted: 04/03/2024] [Indexed: 04/20/2024]
Abstract
BACKGROUND & AIMS High expression of phosphatidylinositol 4-kinase III alpha (PI4KIIIα) correlates with poor survival rates in patients with hepatocellular carcinoma. In addition, hepatitis C virus (HCV) infections activate PI4KIIIα and contribute to hepatocellular carcinoma progression. We aimed at mechanistically understanding the impact of PI4KIIIα on the progression of liver cancer and the potential contribution of HCV in this process. METHODS Several hepatic cell culture and mouse models were used to study the functional importance of PI4KIIIα on liver pathogenesis. Antibody arrays, gene silencing, and PI4KIIIα-specific inhibitor were applied to identify the involved signaling pathways. The contribution of HCV was examined by using HCV infection or overexpression of its nonstructural protein. RESULTS High PI4KIIIα expression and/or activity induced cytoskeletal rearrangements via increased phosphorylation of paxillin and cofilin. This led to morphologic alterations and higher migratory and invasive properties of liver cancer cells. We further identified the liver-specific lipid kinase phosphatidylinositol 3-kinase C2 domain-containing subunit gamma (PIK3C2γ) working downstream of PI4KIIIα in regulation of the cytoskeleton. PIK3C2γ generates plasma membrane phosphatidylinositol 3,4-bisphosphate-enriched, invadopodia-like structures that regulate cytoskeletal reorganization by promoting Akt2 phosphorylation. CONCLUSIONS PI4KIIIα regulates cytoskeleton organization via PIK3C2γ/Akt2/paxillin-cofilin to favor migration and invasion of liver cancer cells. These findings provide mechanistic insight into the contribution of PI4KIIIα and HCV to the progression of liver cancer and identify promising targets for therapeutic intervention.
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Affiliation(s)
- Cong Si Tran
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Julia Kersten
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Jingyi Yan
- Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden; Clinical Microbiology, Karolinska University Hospital, Huddinge, Sweden
| | - Marco Breinig
- Helmholtz-University Group "Cell Plasticity and Epigenetic Remodeling", German Cancer Research Center (DKFZ) and Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
| | - Thorben Huth
- Institute of Pathology, University Hospital Heidelberg, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Tanja Poth
- Center for Model System and Comparative Pathology, Institute of Pathology, University Hospital Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Ombretta Colasanti
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Tobias Riedl
- Division of Chronic Inflammation and Cancer, DKFZ, Heidelberg, Germany
| | - Suzanne Faure-Dupuy
- Division of Chronic Inflammation and Cancer, DKFZ, Heidelberg, Germany; Université Paris Cité, Institut Cochin, INSERM, CNRS, Paris, France
| | - Stefan Diehl
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Lieven Verhoye
- Laboratory of Liver Infectious Diseases, Ghent University, Ghent, Belgium
| | - Teng-Feng Li
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Marit Lingemann
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Philipp Schult
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Gustaf Ahlén
- Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden; Clinical Microbiology, Karolinska University Hospital, Huddinge, Sweden
| | - Lars Frelin
- Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden; Clinical Microbiology, Karolinska University Hospital, Huddinge, Sweden
| | - Florian Kühnel
- Department of Gastroenterology, Hepatology, Infectiology, and Endocrinology, Hannover Medical School, Hannover, Germany
| | - Florian W R Vondran
- Department of General, Visceral and Transplant Surgery, Hannover Medical School, Hannover, Germany; German Centre for Infection Research (DZIF), Partner Site Hannover, Hannover, Germany
| | - Kai Breuhahn
- Institute of Pathology, University Hospital Heidelberg, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Philip Meuleman
- Laboratory of Liver Infectious Diseases, Ghent University, Ghent, Belgium
| | - Mathias Heikenwälder
- Division of Chronic Inflammation and Cancer, DKFZ, Heidelberg, Germany; The M3 Research Institute, Medical Faculty Tübingen, Tübingen, Germany
| | - Peter Schirmacher
- Institute of Pathology, University Hospital Heidelberg, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Ralf Bartenschlager
- DZIF, Partner Site Heidelberg, Heidelberg, Germany; Division of Virus-Associated Carcinogenesis, DKFZ, Heidelberg, Germany; Department of Infectious Diseases, Molecular Virology, Medical Faculty Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Vibor Laketa
- DZIF, Partner Site Heidelberg, Heidelberg, Germany; Department of Infectious Diseases, Virology, Medical Faculty Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Stephanie Roessler
- Institute of Pathology, University Hospital Heidelberg, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany
| | - Darjus Felix Tschaharganeh
- Helmholtz-University Group "Cell Plasticity and Epigenetic Remodeling", German Cancer Research Center (DKFZ) and Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
| | - Matti Sällberg
- Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden; Clinical Microbiology, Karolinska University Hospital, Huddinge, Sweden
| | - Volker Lohmann
- Department of Infectious Diseases, Molecular Virology, Section Virus-Host Interactions, Center for Integrative Infectious Disease Research, Heidelberg University, Medical Faculty Heidelberg, Heidelberg, Germany; DZIF, Partner Site Heidelberg, Heidelberg, Germany.
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3
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Suresh S, Shaw AL, Pemberton JG, Scott MK, Harris NJ, Parson MAH, Jenkins ML, Rohilla P, Alvarez-Prats A, Balla T, Yip CK, Burke JE. Molecular basis for plasma membrane recruitment of PI4KA by EFR3. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.30.587787. [PMID: 38746453 PMCID: PMC11092606 DOI: 10.1101/2024.04.30.587787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The lipid kinase phosphatidylinositol 4 kinase III alpha (PI4KIIIa/PI4KA) is a master regulator of the lipid composition and asymmetry of the plasma membrane. PI4KA exists primarily in a heterotrimeric complex with its regulatory proteins TTC7 and FAM126. Fundamental to PI4KA activity is its targeted recruitment to the plasma membrane by the lipidated proteins EFR3A and EFR3B. Here, we report a cryo-EM structure of the C-terminus of EFR3A bound to the PI4KA-TTC7B-FAM126A complex, with extensive validation using both hydrogen deuterium exchange mass spectrometry (HDX-MS), and mutational analysis. The EFR3A C-terminus undergoes a disorder-order transition upon binding to the PI4KA complex, with an unexpected direct interaction with both TTC7B and FAM126A. Complex disrupting mutations in TTC7B, FAM126A, and EFR3 decrease PI4KA recruitment to the plasma membrane. Multiple post-translational modifications and disease linked mutations map to this site, providing insight into how PI4KA membrane recruitment can be regulated and disrupted in human disease.
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Affiliation(s)
- Sushant Suresh
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Alexandria L Shaw
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Joshua G Pemberton
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
- Current address: Department of Biology, Western University, London, ON, N6A 3K7 Canada
| | - Mackenzie K Scott
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Noah J Harris
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Matthew AH Parson
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Meredith L Jenkins
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Pooja Rohilla
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Alejandro Alvarez-Prats
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Tamas Balla
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Calvin K Yip
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
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4
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Fung SYS, Xǔ XJ, Wu M. Nonlinear dynamics in phosphoinositide metabolism. Curr Opin Cell Biol 2024; 88:102373. [PMID: 38797149 PMCID: PMC11186694 DOI: 10.1016/j.ceb.2024.102373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/26/2024] [Accepted: 05/01/2024] [Indexed: 05/29/2024]
Abstract
Phosphoinositides broadly impact membrane dynamics, signal transduction and cellular physiology. The orchestration of signaling complexity by this seemingly simple metabolic pathway remains an open question. It is increasingly evident that comprehending the complexity of the phosphoinositides metabolic network requires a systems view based on nonlinear dynamics, where the products of metabolism can either positively or negatively modulate enzymatic function. These feedback and feedforward loops may be paradoxical, leading to counterintuitive effects. In this review, we introduce the framework of nonlinear dynamics, emphasizing distinct dynamical regimes such as the excitable state, oscillations, and mixed-mode oscillations-all of which have been experimentally observed in phosphoinositide metabolisms. We delve into how these dynamical behaviors arise from one or multiple network motifs, including positive and negative feedback loops, coherent and incoherent feedforward loops. We explore the current understanding of the molecular circuits responsible for these behaviors. While mapping these circuits presents both conceptual and experimental challenges, redefining cellular behavior based on dynamical state, lipid fluxes, time delay, and network topology is likely essential for a comprehensive understanding of this fundamental metabolic network.
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Affiliation(s)
- Suet Yin Sarah Fung
- Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8002, USA
| | - X J Xǔ
- Department of Physics, Yale University, New Haven, CT, 06511, USA
| | - Min Wu
- Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8002, USA.
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5
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Jo SI, Kim S, Lim JM, Rhee SG, Jeong BG, Cha SS, Chang JB, Kang D. Control of the signaling role of PtdIns(4)P at the plasma membrane through H 2O 2-dependent inactivation of synaptojanin 2 during endocytosis. Redox Biol 2024; 71:103097. [PMID: 38442648 PMCID: PMC10924134 DOI: 10.1016/j.redox.2024.103097] [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: 12/03/2023] [Revised: 02/16/2024] [Accepted: 02/18/2024] [Indexed: 03/07/2024] Open
Abstract
Phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] is implicated in various processes, including hormone-induced signal transduction, endocytosis, and exocytosis in the plasma membrane. However, how H2O2 accumulation regulates the levels of PtdIns(4,5)P2 in the plasma membrane in cells stimulated with epidermal growth factors (EGFs) is not known. We show that a plasma membrane PtdIns(4,5)P2-degrading enzyme, synaptojanin (Synj) phosphatase, is inactivated through oxidation by H2O2. Intriguingly, H2O2 inhibits the 4-phosphatase activity of Synj but not the 5-phosphatase activity. In EGF-activated cells, the oxidation of Synj dual phosphatase is required for the transient increase in the plasma membrane levels of phosphatidylinositol 4-phosphate [PtdIns(4)P], which can control EGF receptor-mediated endocytosis. These results indicate that intracellular H2O2 molecules act as signaling mediators to fine-tune endocytosis by controlling the stability of plasma membrane PtdIns(4)P, an intermediate product of Synj phosphoinositide dual phosphatase.
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Affiliation(s)
- Su In Jo
- Department of Life Science, Ewha Womans University, Seoul, Republic of Korea
| | - Suree Kim
- Fluorescence Core Imaging Center and Bioimaging Data Curation Center, Ewha Womans University, Seoul, Republic of Korea
| | - Jung Mi Lim
- Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Sue Goo Rhee
- Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, MD, 20892, USA
| | | | - Sun-Shin Cha
- R&D Division, TODD PHARM CO. LTD., Seoul, Republic of Korea; Department of Chemistry & Nanoscience, Ewha Womans University, Seoul, Republic of Korea
| | - Jae-Byum Chang
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Dongmin Kang
- Department of Life Science, Ewha Womans University, Seoul, Republic of Korea; Fluorescence Core Imaging Center and Bioimaging Data Curation Center, Ewha Womans University, Seoul, Republic of Korea.
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6
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Udine E, DeJesus-Hernandez M, Tian S, das Neves SP, Crook R, Finch NA, Baker MC, Pottier C, Graff-Radford NR, Boeve BF, Petersen RC, Knopman DS, Josephs KA, Oskarsson B, Da Mesquita S, Petrucelli L, Gendron TF, Dickson DW, Rademakers R, van Blitterswijk M. Abundant transcriptomic alterations in the human cerebellum of patients with a C9orf72 repeat expansion. Acta Neuropathol 2024; 147:73. [PMID: 38641715 PMCID: PMC11031479 DOI: 10.1007/s00401-024-02720-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 02/28/2024] [Accepted: 03/18/2024] [Indexed: 04/21/2024]
Abstract
The most prominent genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) is a repeat expansion in the gene C9orf72. Importantly, the transcriptomic consequences of the C9orf72 repeat expansion remain largely unclear. Here, we used short-read RNA sequencing (RNAseq) to profile the cerebellar transcriptome, detecting alterations in patients with a C9orf72 repeat expansion. We focused on the cerebellum, since key C9orf72-related pathologies are abundant in this neuroanatomical region, yet TDP-43 pathology and neuronal loss are minimal. Consistent with previous work, we showed a reduction in the expression of the C9orf72 gene and an elevation in homeobox genes, when comparing patients with the expansion to both patients without the C9orf72 repeat expansion and control subjects. Interestingly, we identified more than 1000 alternative splicing events, including 4 in genes previously associated with ALS and/or FTLD. We also found an increase of cryptic splicing in C9orf72 patients compared to patients without the expansion and controls. Furthermore, we demonstrated that the expression level of select RNA-binding proteins is associated with cryptic splice junction inclusion. Overall, this study explores the presence of widespread transcriptomic changes in the cerebellum, a region not confounded by severe neurodegeneration, in post-mortem tissue from C9orf72 patients.
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Affiliation(s)
- Evan Udine
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | | | - Shulan Tian
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, 55905, USA
| | | | - Richard Crook
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
| | - NiCole A Finch
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
| | - Matthew C Baker
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
| | - Cyril Pottier
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
| | | | | | | | | | | | - Björn Oskarsson
- Department of Neurology, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Sandro Da Mesquita
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Tania F Gendron
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Marka van Blitterswijk
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd S, Jacksonville, FL, 32224, USA.
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA.
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7
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Zhao H, Kong F, Yu W, Zhao H, Zhang J, Zhou J, Meng X. Locational and functional characterization of PI4KB in the mouse embryo. J Cell Physiol 2024; 239:e31195. [PMID: 38230579 DOI: 10.1002/jcp.31195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/27/2023] [Accepted: 01/03/2024] [Indexed: 01/18/2024]
Abstract
Phosphatidylinositol 4-kinase beta (PI4KB) is a member of the PI4K family, which is mainly enriched and functions in the Golgi apparatus. The kinase domain of PI4KB catalyzes the phosphorylation of phosphatidylinositol to form phosphatidylinositol 4-phosphate, a process that regulates various sub-cellular events, such as non-vesicular cholesterol and ceramide transport, protein glycosylation, and vesicle transport, as well as cytoplasmic division. In this study, a strain of PI4KB knockout mouse, immunofluorescence, reverse transcription polymerase chain reaction and microinjection were used to characterize the cytological location and biological function of PI4KB in the mouse embryos. we found that knocking down Pi4kb in mouse embryos resulted in embryonic lethality at around embryonic day (E) 7.5. Additionally, we observed dramatic fluctuations in PI4KB expression during the development of preimplantation embryos, with high expression in the 4-cell and morula stages. PI4KB colocalized with the Golgi marker protein TGN46 in the perinuclear and cytoplasmic regions in early blastomeres. Postimplantation, PI4KB was highly expressed in the epiblast of E7.5 embryos. Treatment of embryos with PI4KB inhibitors was found to inhibit the development of the morula into a blastocyst and the normal progression of cytoplasmic division during the formation of a 4-cell embryo. These findings suggest that PI4KB plays an important role in mouse embryogenesis by regulating various intracellular vital functions of embryonic cells.
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Affiliation(s)
- Haoyu Zhao
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Centre for Cell Structure and Function, Shandong Normal University, Jinan, China
| | - Fengyun Kong
- Reproductive Medical Center, The Second Hospital Affiliated to Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Weikai Yu
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Centre for Cell Structure and Function, Shandong Normal University, Jinan, China
| | - Huijie Zhao
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Centre for Cell Structure and Function, Shandong Normal University, Jinan, China
| | - Jingjing Zhang
- Affiliated Hospital of Guangdong Medical University & Key Laboratory of Zebrafish Model for Development and Disease of Guangdong Medical University, Zhanjiang, China
| | - Jun Zhou
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Centre for Cell Structure and Function, Shandong Normal University, Jinan, China
| | - Xiaoqian Meng
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Centre for Cell Structure and Function, Shandong Normal University, Jinan, China
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8
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Sun S, Zhao G, Jia M, Jiang Q, Li S, Wang H, Li W, Wang Y, Bian X, Zhao YG, Huang X, Yang G, Cai H, Pastor-Pareja JC, Ge L, Zhang C, Hu J. Stay in touch with the endoplasmic reticulum. SCIENCE CHINA. LIFE SCIENCES 2024; 67:230-257. [PMID: 38212460 DOI: 10.1007/s11427-023-2443-9] [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: 03/19/2023] [Accepted: 08/28/2023] [Indexed: 01/13/2024]
Abstract
The endoplasmic reticulum (ER), which is composed of a continuous network of tubules and sheets, forms the most widely distributed membrane system in eukaryotic cells. As a result, it engages a variety of organelles by establishing membrane contact sites (MCSs). These contacts regulate organelle positioning and remodeling, including fusion and fission, facilitate precise lipid exchange, and couple vital signaling events. Here, we systematically review recent advances and converging themes on ER-involved organellar contact. The molecular basis, cellular influence, and potential physiological functions for ER/nuclear envelope contacts with mitochondria, Golgi, endosomes, lysosomes, lipid droplets, autophagosomes, and plasma membrane are summarized.
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Affiliation(s)
- Sha Sun
- National Laboratory of Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China
| | - Gan Zhao
- The Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing, 100871, China
| | - Mingkang Jia
- The Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing, 100871, China
| | - Qing Jiang
- The Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing, 100871, China
| | - Shulin Li
- State Key Laboratory of Membrane Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Haibin Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China
| | - Wenjing Li
- Laboratory of Computational Biology & Machine Intelligence, School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yunyun Wang
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Xin Bian
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China.
| | - Yan G Zhao
- Brain Research Center, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China.
| | - Xun Huang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Ge Yang
- Laboratory of Computational Biology & Machine Intelligence, School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Huaqing Cai
- National Laboratory of Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Jose C Pastor-Pareja
- State Key Laboratory of Membrane Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Institute of Neurosciences, Consejo Superior de Investigaciones Cientfflcas-Universidad Miguel Hernandez, San Juan de Alicante, 03550, Spain.
| | - Liang Ge
- State Key Laboratory of Membrane Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
| | - Chuanmao Zhang
- The Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing, 100871, China.
| | - Junjie Hu
- National Laboratory of Biomacromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100101, China.
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9
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Li G, Wu Y, Zhang Y, Wang H, Li M, He D, Guan W, Yao H. Research progress on phosphatidylinositol 4-kinase inhibitors. Biochem Pharmacol 2024; 220:115993. [PMID: 38151075 DOI: 10.1016/j.bcp.2023.115993] [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: 10/23/2023] [Revised: 12/07/2023] [Accepted: 12/18/2023] [Indexed: 12/29/2023]
Abstract
Phosphatidylinositol 4-kinases (PI4Ks) could phosphorylate phosphatidylinositol (PI) to produce phosphatidylinositol 4-phosphate (PI4P) and maintain its metabolic balance and location. PI4P, the most abundant monophosphate inositol in eukaryotic cells, is a precursor of higher phosphoinositols and an essential substrate for the PLC/PKC and PI3K/Akt signaling pathways. PI4Ks regulate vesicle transport, signal transduction, cytokinesis, and cell unity, and are involved in various physiological and pathological processes, including infection and growth of parasites such as Plasmodium and Cryptosporidium, replication and survival of RNA viruses, and the development of tumors and nervous system diseases. The development of novel drugs targeting PI4Ks and PI4P has been the focus of the research and clinical application of drugs, especially in recent years. In particular, PI4K inhibitors have made great progress in the treatment of malaria and cryptosporidiosis. We describe the biological characteristics of PI4Ks; summarize the physiological functions and effector proteins of PI4P; and analyze the structural basis of selective PI4K inhibitors for the treatment of human diseases in this review. Herein, this review mainly summarizes the developments in the structure and enzyme activity of PI4K inhibitors.
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Affiliation(s)
- Gang Li
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510260, China
| | - Yanting Wu
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510260, China; Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, 999077, China
| | - Yali Zhang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510260, China
| | - Huamin Wang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510260, China
| | - Mengjie Li
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510260, China
| | - Dengqin He
- School of Biotechnology and Health Science, Wuyi University, 22 Dongchengcun, Jiangmen, Guangdong, 529020, China
| | - Wen Guan
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510260, China
| | - Hongliang Yao
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510260, China.
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10
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Wei X, Wang J, Yang E, Zhang Y, Qian Q, Li X, Huang F, Sun B. Efr3b is essential for social recognition by modulating the excitability of CA2 pyramidal neurons. Proc Natl Acad Sci U S A 2024; 121:e2314557121. [PMID: 38190534 PMCID: PMC10801834 DOI: 10.1073/pnas.2314557121] [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: 08/29/2023] [Accepted: 11/29/2023] [Indexed: 01/10/2024] Open
Abstract
CA2 pyramidal neurons (PNs) are associated with social behaviors. The mechanisms, however, remain to be fully investigated. Here, we report that Efr3b, a protein essential for phospholipid metabolism at the plasma membrane, is widely expressed in the brain, especially in the hippocampal CA2/CA3 areas. To assess the functional significance of Efr3b in the brain, we generated Efr3bf/f mice and crossed them with Nestin-cre mice to delete Efr3b specifically in the brain. We find that Efr3b deficiency in the brain leads to deficits of social novelty recognition and hypoexcitability of CA2 PNs. We then knocked down the expression of Efr3b specifically in CA2 PNs of C57BL/6J mice, and our results showed that reducing Efr3b in CA2 PNs also resulted in deficits of social novelty recognition and hypoexcitability of CA2 PNs. More interestingly, restoring the expression of Efr3b in CA2 PNs enhances their excitability and improves social novelty recognition in Efr3b-deficient mice. Furthermore, direct activation of CA2 PNs with chemogenetics improves social behaviors in Efr3b-deficient mice. Together, our data suggest that Efr3b is essential for social novelty by modulating the excitability of CA2 PNs.
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Affiliation(s)
- Xiaojie Wei
- Department of Anesthesiology of the Children’s Hospital and School of Brain Science and Brain Medicine, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Zhejiang University, Hangzhou310058, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou310058, China
- Children’s Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou310020, China
| | - Jing Wang
- Department of Anesthesiology of the Children’s Hospital and School of Brain Science and Brain Medicine, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Zhejiang University, Hangzhou310058, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou310058, China
- School of Medicine, Shaoxing University, Shaoxing312000, China
| | - Enlu Yang
- Department of Anesthesiology of the Children’s Hospital and School of Brain Science and Brain Medicine, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Zhejiang University, Hangzhou310058, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou310058, China
| | - Yiping Zhang
- Department of Anesthesiology of the Children’s Hospital and School of Brain Science and Brain Medicine, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Zhejiang University, Hangzhou310058, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou310058, China
| | - Qi Qian
- Department of Anesthesiology of the Children’s Hospital and School of Brain Science and Brain Medicine, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Zhejiang University, Hangzhou310058, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou310058, China
| | - Xuekun Li
- Children’s Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou310020, China
| | - Fude Huang
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing100190, China
- Nuo-Beta Pharmaceutical Technology, Co. Ltd., Shanghai201210, China
| | - Binggui Sun
- Department of Anesthesiology of the Children’s Hospital and School of Brain Science and Brain Medicine, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Zhejiang University, Hangzhou310058, China
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou310058, China
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11
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Suresh S, Burke JE. Structural basis for the conserved roles of PI4KA and its regulatory partners and their misregulation in disease. Adv Biol Regul 2023; 90:100996. [PMID: 37979461 DOI: 10.1016/j.jbior.2023.100996] [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: 09/24/2023] [Accepted: 10/17/2023] [Indexed: 11/20/2023]
Abstract
The type III Phosphatidylinositol 4-kinase alpha (PI4KA) is an essential lipid kinase that is a master regulator of phosphoinositide signalling at the plasma membrane (PM). It produces the predominant pool of phosphatidylinositol 4-phosphate (PI4P) at the PM, with this being essential in lipid transport and in regulating the PLC and PI3K signalling pathways. PI4KA is essential and is highly conserved in all eukaryotes. In yeast, the PI4KA ortholog stt4 predominantly exists as a heterodimer with its regulatory partner ypp1. In higher eukaryotes, PI4KA instead primarily forms a heterotrimer with a TTC7 subunit (ortholog of ypp1) and a FAM126 subunit. In all eukaryotes PI4KA is recruited to the plasma membrane by the protein EFR3, which does not directly bind PI4KA, but instead binds to the TTC7/ypp1 regulatory partner. Misregulation in PI4KA or its regulatory partners is involved in myriad human diseases, including loss of function mutations in neurodevelopmental and inflammatory intestinal disorders and gain of function in human cancers. This review describes an in-depth analysis of the structure function of PI4KA and its regulatory partners, with a major focus on comparing and contrasting the differences in regulation of PI4KA throughout evolution.
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Affiliation(s)
- Sushant Suresh
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, V8W 2Y2, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, V8W 2Y2, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada.
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12
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Govindarajan B, Sbrissa D, Pressprich M, Kim S, Rishi AK, Vaishampayan U, Cher ML, Chinni SR. Adaptor proteins mediate CXCR4 and PI4KA crosstalk in prostate cancer cells and the significance of PI4KA in bone tumor growth. Sci Rep 2023; 13:20634. [PMID: 37996444 PMCID: PMC10667255 DOI: 10.1038/s41598-023-47633-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023] Open
Abstract
The chemokine receptor, CXCR4 signaling regulates cell growth, invasion, and metastasis to the bone-marrow niche in prostate cancer (PCa). Previously, we established that CXCR4 interacts with phosphatidylinositol 4-kinase IIIα (PI4KIIIα encoded by PI4KA) through its adaptor proteins and PI4KA overexpressed in the PCa metastasis. To further characterize how the CXCR4-PI4KIIIα axis promotes PCa metastasis, here we identify CXCR4 binds to PI4KIIIα adaptor proteins TTC7 and this interaction induce plasma membrane PI4P production in prostate cancer cells. Inhibiting PI4KIIIα or TTC7 reduces plasma membrane PI4P production, cellular invasion, and bone tumor growth. Using metastatic biopsy sequencing, we found PI4KA expression in tumors correlated with overall survival and contributes to immunosuppressive bone tumor microenvironment through preferentially enriching non-activated and immunosuppressive macrophage populations. Altogether we have characterized the chemokine signaling axis through CXCR4-PI4KIIIα interaction contributing to the growth of prostate cancer bone metastasis.
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Affiliation(s)
- Barani Govindarajan
- Department of Pathology, Wayne State University, School of Medicine, 9245 Scott Hall, 540 E. Canfield Avenue, Detroit, MI, 48201, USA
| | - Diego Sbrissa
- Department of Urology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA
| | - Mark Pressprich
- Department of Urology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA
| | - Seongho Kim
- Department of Oncology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA
- Biostatistics and Bioinformatics Core, Wayne State University, School of Medicine, Detroit, MI, 48201, USA
| | - Arun K Rishi
- Department of Oncology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA
| | - Ulka Vaishampayan
- Department of Oncology, University of Michigan, 7217 Rogel Cancer Center, Ann Arbor, MI, USA
| | - Michael L Cher
- Department of Pathology, Wayne State University, School of Medicine, 9245 Scott Hall, 540 E. Canfield Avenue, Detroit, MI, 48201, USA
- Department of Urology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA
- Department of Oncology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA
| | - Sreenivasa R Chinni
- Department of Pathology, Wayne State University, School of Medicine, 9245 Scott Hall, 540 E. Canfield Avenue, Detroit, MI, 48201, USA.
- Department of Urology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA.
- Department of Oncology, Wayne State University, School of Medicine, Detroit, MI, 48201, USA.
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13
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Constantin S, Sokanovic SJ, Mochimaru Y, Smiljanic K, Sivcev S, Prévide RM, Wray S, Balla T, Stojilkovic SS. Postnatal Development and Maintenance of Functional Pituitary Gonadotrophs Is Dependent on PI4-Kinase A. Endocrinology 2023; 164:bqad168. [PMID: 37935042 PMCID: PMC10652335 DOI: 10.1210/endocr/bqad168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/27/2023] [Accepted: 11/01/2023] [Indexed: 11/09/2023]
Abstract
Postnatal development of functional pituitary gonadotrophs is necessary for maturation of the hypothalamic-pituitary-gonadal axis, puberty, and reproduction. Here we examined the role of PI4-kinase A, which catalyzes the biosynthesis of PI4P in mouse reproduction by knocking out this enzyme in cells expressing the gonadotropin-releasing hormone (GnRH) receptor. Knockout (KO) mice were infertile, reflecting underdeveloped gonads and reproductive tracts and lack of puberty. The number and distribution of hypothalamic GnRH neurons and Gnrh1 expression in postnatal KOs were not affected, whereas Kiss1/kisspeptin expression was increased. KO of PI4-kinase A also did not alter embryonic establishment and neonatal development and function of the gonadotroph population. However, during the postnatal period, there was a progressive loss of expression of gonadotroph-specific genes, including Fshb, Lhb, and Gnrhr, accompanied by low gonadotropin synthesis. The postnatal gonadotroph population also progressively declined, reaching approximately one-third of that observed in controls at 3 months of age. In these residual gonadotrophs, GnRH-dependent calcium signaling and calcium-dependent membrane potential changes were lost, but intracellular administration of inositol-14,5-trisphosphate rescued this signaling. These results indicate a key role for PI4-kinase A in the postnatal development and maintenance of a functional gonadotroph population.
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Affiliation(s)
- Stephanie Constantin
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
- Cellular and Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Srdjan J Sokanovic
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yuta Mochimaru
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kosara Smiljanic
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sonja Sivcev
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rafael M Prévide
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Susan Wray
- Cellular and Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tamas Balla
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stanko S Stojilkovic
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
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14
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Geiser A, Foylan S, Tinning PW, Bryant NJ, Gould GW. GLUT4 dispersal at the plasma membrane of adipocytes: a super-resolved journey. Biosci Rep 2023; 43:BSR20230946. [PMID: 37791639 PMCID: PMC10600063 DOI: 10.1042/bsr20230946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/05/2023] Open
Abstract
In adipose tissue, insulin stimulates glucose uptake by mediating the translocation of GLUT4 from intracellular vesicles to the plasma membrane. In 2010, insulin was revealed to also have a fundamental impact on the spatial distribution of GLUT4 within the plasma membrane, with the existence of two GLUT4 populations at the plasma membrane being defined: (1) as stationary clusters and (2) as diffusible monomers. In this model, in the absence of insulin, plasma membrane-fused GLUT4 are found to behave as clusters. These clusters are thought to arise from exocytic events that retain GLUT4 at their fusion sites; this has been proposed to function as an intermediate hub between GLUT4 exocytosis and re-internalisation. By contrast, insulin stimulation induces the dispersal of GLUT4 clusters into monomers and favours a distinct type of GLUT4-vesicle fusion event, known as fusion-with-release exocytosis. Here, we review how super-resolution microscopy approaches have allowed investigation of the characteristics of plasma membrane-fused GLUT4 and further discuss regulatory step(s) involved in the GLUT4 dispersal machinery, introducing the scaffold protein EFR3 which facilitates localisation of phosphatidylinositol 4-kinase type IIIα (PI4KIIIα) to the cell surface. We consider how dispersal may be linked to the control of transporter activity, consider whether macro-organisation may be a widely used phenomenon to control proteins within the plasma membrane, and speculate on the origin of different forms of GLUT4-vesicle exocytosis.
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Affiliation(s)
- Angéline Geiser
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
| | - Shannan Foylan
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
| | - Peter W Tinning
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
| | - Nia J Bryant
- Department of Biology, University of York, Heslington, York, U.K
| | - Gwyn W Gould
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, U.K
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15
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Derkaczew M, Martyniuk P, Hofman R, Rutkowski K, Osowski A, Wojtkiewicz J. The Genetic Background of Abnormalities in Metabolic Pathways of Phosphoinositides and Their Linkage with the Myotubular Myopathies, Neurodegenerative Disorders, and Carcinogenesis. Biomolecules 2023; 13:1550. [PMID: 37892232 PMCID: PMC10605126 DOI: 10.3390/biom13101550] [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: 08/27/2023] [Revised: 09/16/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Myo-inositol belongs to one of the sugar alcohol groups known as cyclitols. Phosphatidylinositols are one of the derivatives of Myo-inositol, and constitute important mediators in many intracellular processes such as cell growth, cell differentiation, receptor recycling, cytoskeletal organization, and membrane fusion. They also have even more functions that are essential for cell survival. Mutations in genes encoding phosphatidylinositols and their derivatives can lead to many disorders. This review aims to perform an in-depth analysis of these connections. Many authors emphasize the significant influence of phosphatidylinositols and phosphatidylinositols' phosphates in the pathogenesis of myotubular myopathies, neurodegenerative disorders, carcinogenesis, and other less frequently observed diseases. In our review, we have focused on three of the most often mentioned groups of disorders. Inositols are the topic of many studies, and yet, there are no clear results of successful clinical trials. Analysis of the available literature gives promising results and shows that further research is still needed.
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Affiliation(s)
- Maria Derkaczew
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Piotr Martyniuk
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Robert Hofman
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Krzysztof Rutkowski
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- The Nicolaus Copernicus Municipal Polyclinical Hospital in Olsztyn, 10-045 Olsztyn, Poland
| | - Adam Osowski
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Joanna Wojtkiewicz
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
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16
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Gajardo T, Bernard M, Lô M, Turck E, Leveau C, El-Daher MT, Deslys A, Panikulam P, Menche C, Kurowska M, Le Lay G, Barbier L, Moshous D, Neven B, Farin HF, Fischer A, Ménasché G, de Saint Basile G, Vargas P, Sepulveda FE. Actin dynamics regulation by TTC7A/PI4KIIIα limits DNA damage and cell death under confinement. J Allergy Clin Immunol 2023; 152:949-960. [PMID: 37390900 DOI: 10.1016/j.jaci.2023.06.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 05/24/2023] [Accepted: 06/01/2023] [Indexed: 07/02/2023]
Abstract
BACKGROUND The actin cytoskeleton has a crucial role in the maintenance of the immune homeostasis by controlling various cellular processes, including cell migration. Mutations in TTC7A have been described as the cause of a primary immunodeficiency associated to different degrees of gut involvement and alterations in the actin cytoskeleton dynamics. OBJECTIVES This study investigates the impact of TTC7A deficiency in immune homeostasis. In particular, the role of the TTC7A/phosphatidylinositol 4 kinase type III α pathway in the control of leukocyte migration and actin dynamics. METHODS Microfabricated devices were leveraged to study cell migration and actin dynamics of murine and patient-derived leukocytes under confinement at the single-cell level. RESULTS We show that TTC7A-deficient lymphocytes exhibit an altered cell migration and reduced capacity to deform through narrow gaps. Mechanistically, TTC7A-deficient phenotype resulted from impaired phosphoinositide signaling, leading to the downregulation of the phosphoinositide 3-kinase/AKT/RHOA regulatory axis and imbalanced actin cytoskeleton dynamics. TTC7A-associated phenotype resulted in impaired cell motility, accumulation of DNA damage, and increased cell death in dense 3-dimensional gels in the presence of chemokines. CONCLUSIONS These results highlight a novel role of TTC7A as a critical regulator of lymphocyte migration. Impairment of this cellular function is likely to contribute to the pathophysiology underlying progressive immunodeficiency in patients.
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Affiliation(s)
- Tania Gajardo
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Mathilde Bernard
- UMR 144, Institut Curie, Paris, France; Institut Pierre-Gilles de Gennes, Paris Sciences and Letters Research University, Paris, France
| | - Marie Lô
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Elisa Turck
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Claire Leveau
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Marie-Thérèse El-Daher
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Alexandre Deslys
- Leukomotion Lab, Université de Paris Cité, CNRS, INSERM, Institut Necker-Enfants Malades, F-75015 Paris, France
| | - Patricia Panikulam
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Constantin Menche
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Main, Germany; Frankfurt Cancer Institute, Goethe University Frankfurt, Frankfurt, Germany
| | - Mathieu Kurowska
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Gregoire Le Lay
- UMR 144, Institut Curie, Paris, France; Institut Pierre-Gilles de Gennes, Paris Sciences and Letters Research University, Paris, France
| | - Lucie Barbier
- UMR 144, Institut Curie, Paris, France; Institut Pierre-Gilles de Gennes, Paris Sciences and Letters Research University, Paris, France
| | - Despina Moshous
- Imagine Institute, Université de Paris Cité, Paris, France; Pediatric Immunology Hematology and Rheumatology Department, Université Paris Cité, Paris, France
| | - Bénédicte Neven
- Imagine Institute, Université de Paris Cité, Paris, France; Pediatric Immunology Hematology and Rheumatology Department, Université Paris Cité, Paris, France
| | - Henner F Farin
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Main, Germany; Frankfurt Cancer Institute, Goethe University Frankfurt, Frankfurt, Germany
| | - Alain Fischer
- Imagine Institute, Université de Paris Cité, Paris, France; Pediatric Immunology Hematology and Rheumatology Department, Université Paris Cité, Paris, France; Collège de France, Paris, France
| | - Gaël Ménasché
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France
| | - Geneviève de Saint Basile
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France; Centre d'Etude des Déficits Immunitaires, Necker-Enfants Malades University Hospital, Assistance Publique-Hôpitaux de Paris, Université Paris Cité, Paris, France
| | - Pablo Vargas
- UMR 144, Institut Curie, Paris, France; Institut Pierre-Gilles de Gennes, Paris Sciences and Letters Research University, Paris, France; Leukomotion Lab, Université de Paris Cité, CNRS, INSERM, Institut Necker-Enfants Malades, F-75015 Paris, France.
| | - Fernando E Sepulveda
- Molecular Basis of Altered Immune Homeostasis Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM) Unite Mixte de Recherche (UMR) 1163, Paris, France; Imagine Institute, Université de Paris Cité, Paris, France; CNRS, Paris, France.
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17
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Daly C, Plouffe B. Gα q signalling from endosomes: A new conundrum. Br J Pharmacol 2023. [PMID: 37740273 DOI: 10.1111/bph.16248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/08/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023] Open
Abstract
G-protein-coupled receptors (GPCRs) constitute the largest family of membrane receptors, and are involved in the transmission of a variety of extracellular stimuli such as hormones, neurotransmitters, light and odorants into intracellular responses. They regulate every aspect of physiology and, for this reason, about one third of all marketed drugs target these receptors. Classically, upon binding to their agonist, GPCRs are thought to activate G-proteins from the plasma membrane and to stop signalling by subsequent desensitisation and endocytosis. However, accumulating evidence indicates that, upon internalisation, some GPCRs can continue to activate G-proteins in endosomes. Importantly, this signalling from endomembranes mediates alternative cellular responses other than signalling at the plasma membrane. Endosomal G-protein signalling and its physiological relevance have been abundantly documented for Gαs - and Gαi -coupled receptors. Recently, some Gαq -coupled receptors have been reported to activate Gαq on endosomes and mediate important cellular processes. However, several questions relative to the series of cellular events required to translate endosomal Gαq activation into cellular responses remain unanswered and constitute a new conundrum. How are these responses in endosomes mediated in the quasi absence of the substrate for the canonical Gαq -activated effector? Is there another effector? Is there another substrate? If so, how does this alternative endosomal effector or substrate produce a downstream signal? This review aims to unravel and discuss these important questions, and proposes possible routes of investigation.
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Affiliation(s)
- Carole Daly
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
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18
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Arabiotorre A, Bankaitis VA, Grabon A. Regulation of phosphoinositide metabolism in Apicomplexan parasites. Front Cell Dev Biol 2023; 11:1163574. [PMID: 37791074 PMCID: PMC10543664 DOI: 10.3389/fcell.2023.1163574] [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: 02/10/2023] [Accepted: 07/11/2023] [Indexed: 10/05/2023] Open
Abstract
Phosphoinositides are a biologically essential class of phospholipids that contribute to organelle membrane identity, modulate membrane trafficking pathways, and are central components of major signal transduction pathways that operate on the cytosolic face of intracellular membranes in eukaryotes. Apicomplexans (such as Toxoplasma gondii and Plasmodium spp.) are obligate intracellular parasites that are important causative agents of disease in animals and humans. Recent advances in molecular and cell biology of Apicomplexan parasites reveal important roles for phosphoinositide signaling in key aspects of parasitosis. These include invasion of host cells, intracellular survival and replication, egress from host cells, and extracellular motility. As Apicomplexans have adapted to the organization of essential signaling pathways to accommodate their complex parasitic lifestyle, these organisms offer experimentally tractable systems for studying the evolution, conservation, and repurposing of phosphoinositide signaling. In this review, we describe the regulatory mechanisms that control the spatial and temporal regulation of phosphoinositides in the Apicomplexan parasites Plasmodium and T. gondii. We further discuss the similarities and differences presented by Apicomplexan phosphoinositide signaling relative to how these pathways are regulated in other eukaryotic organisms.
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Affiliation(s)
- Angela Arabiotorre
- Department of Cell Biology and Genetics, College of Medicine Texas A&M Health Sciences Center College Station, Bryan, TX, United States
| | - Vytas A. Bankaitis
- Department of Cell Biology and Genetics, College of Medicine Texas A&M Health Sciences Center College Station, Bryan, TX, United States
- Department of Biochemistry and Biophysics Texas A&M University College Station, College Station, TX, United States
- Department of Chemistry Texas A&M University College Station, College Station, TX, United States
| | - Aby Grabon
- Department of Cell Biology and Genetics, College of Medicine Texas A&M Health Sciences Center College Station, Bryan, TX, United States
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19
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Wen T, Thapa N, Cryns VL, Anderson RA. Regulation of Phosphoinositide Signaling by Scaffolds at Cytoplasmic Membranes. Biomolecules 2023; 13:1297. [PMID: 37759697 PMCID: PMC10526805 DOI: 10.3390/biom13091297] [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: 08/01/2023] [Revised: 08/21/2023] [Accepted: 08/22/2023] [Indexed: 09/29/2023] Open
Abstract
Cytoplasmic phosphoinositides (PI) are critical regulators of the membrane-cytosol interface that control a myriad of cellular functions despite their low abundance among phospholipids. The metabolic cycle that generates different PI species is crucial to their regulatory role, controlling membrane dynamics, vesicular trafficking, signal transduction, and other key cellular events. The synthesis of phosphatidylinositol (3,4,5)-triphosphate (PI3,4,5P3) in the cytoplamic PI3K/Akt pathway is central to the life and death of a cell. This review will focus on the emerging evidence that scaffold proteins regulate the PI3K/Akt pathway in distinct membrane structures in response to diverse stimuli, challenging the belief that the plasma membrane is the predominant site for PI3k/Akt signaling. In addition, we will discuss how PIs regulate the recruitment of specific scaffolding complexes to membrane structures to coordinate vesicle formation, fusion, and reformation during autophagy as well as a novel lysosome repair pathway.
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Affiliation(s)
- Tianmu Wen
- School of Medicine and Public Health, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705, USA; (T.W.); (N.T.)
| | - Narendra Thapa
- School of Medicine and Public Health, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705, USA; (T.W.); (N.T.)
| | - Vincent L. Cryns
- Department of Medicine, University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705, USA
| | - Richard A. Anderson
- School of Medicine and Public Health, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705, USA; (T.W.); (N.T.)
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20
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Thallmair V, Schultz L, Evers S, Jolie T, Goecke C, Leitner MG, Thallmair S, Oliver D. Localization of the tubby domain, a PI(4,5)P2 biosensor, to E-Syt3-rich endoplasmic reticulum-plasma membrane junctions. J Cell Sci 2023; 136:jcs260848. [PMID: 37401342 PMCID: PMC10445746 DOI: 10.1242/jcs.260848] [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: 11/30/2022] [Accepted: 06/26/2023] [Indexed: 07/05/2023] Open
Abstract
The phospholipid phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] acts as a signaling lipid at the plasma membrane (PM) with pleiotropic regulatory actions on multiple cellular processes. Signaling specificity might result from spatiotemporal compartmentalization of the lipid and from combinatorial binding of PI(4,5)P2 effector proteins to additional membrane components. Here, we analyzed the spatial distribution of tubbyCT, a paradigmatic PI(4,5)P2-binding domain, in live mammalian cells by total internal reflection fluorescence (TIRF) microscopy and molecular dynamics simulations. We found that unlike other well-characterized PI(4,5)P2 recognition domains, tubbyCT segregates into distinct domains within the PM. TubbyCT enrichment occurred at contact sites between PM and endoplasmic reticulum (ER) (i.e. at ER-PM junctions) as shown by colocalization with ER-PM markers. Localization to these sites was mediated in a combinatorial manner by binding to PI(4,5)P2 and by interaction with a cytosolic domain of extended synaptotagmin 3 (E-Syt3), but not other E-Syt isoforms. Selective localization to these structures suggests that tubbyCT is a novel selective reporter for a ER-PM junctional pool of PI(4,5)P2. Finally, we found that association with ER-PM junctions is a conserved feature of tubby-like proteins (TULPs), suggesting an as-yet-unknown function of TULPs.
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Affiliation(s)
- Veronika Thallmair
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps UniversityMarburg, 35037 Marburg, Germany
| | - Lea Schultz
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Saskia Evers
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Theresa Jolie
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Christian Goecke
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Michael G. Leitner
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, 6020 Innsbruck, Austria
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH&Co.KG, Birkendorfer Str. 65, 88400 Biberach an der Riß, Germany
| | - Sebastian Thallmair
- Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main, Germany
- Groningen Biomolecular Sciences and Biotechnology Institute and The Zernike Institute for Advanced Material, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Dominik Oliver
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps UniversityMarburg, 35037 Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), Universities of Marburg and Giessen, 35032 Marburg, Germany
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21
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Barlow-Busch I, Shaw AL, Burke JE. PI4KA and PIKfyve: Essential phosphoinositide signaling enzymes involved in myriad human diseases. Curr Opin Cell Biol 2023; 83:102207. [PMID: 37453227 DOI: 10.1016/j.ceb.2023.102207] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 06/09/2023] [Accepted: 06/19/2023] [Indexed: 07/18/2023]
Abstract
Lipid phosphoinositides are master regulators of multiple cellular functions. Misregulation of the activity of the lipid kinases that generate phosphoinositides is causative of human diseases, including cancer, neurodegeneration, developmental disorders, immunodeficiencies, and inflammatory disease. This review will present a summary of recent discoveries on the roles of two phosphoinositide kinases (PI4KA and PIKfyve), which have emerged as targets for therapeutic intervention. Phosphatidylinositol 4-kinase alpha (PI4KA) generates PI4P at the plasma membrane and PIKfyve generates PI(3,5)P2 at endo-lysosomal membranes. Both of these enzymes exist as multi-protein mega complexes that are under myriad levels of regulation. Human disease can be caused by either loss or gain-of-function of these complexes, so understanding how they are regulated will be essential in the design of therapeutics. We will summarize insight into how these enzymes are regulated by their protein-binding partners, with a major focus on the unanswered questions of how their activity is controlled.
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Affiliation(s)
- Isobel Barlow-Busch
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Alexandria L Shaw
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
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22
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Andersen V, Bennike TB, Bang C, Rioux JD, Hébert-Milette I, Sato T, Hansen AK, Nielsen OH. Investigating the Crime Scene-Molecular Signatures in Inflammatory Bowel Disease. Int J Mol Sci 2023; 24:11217. [PMID: 37446397 PMCID: PMC10342864 DOI: 10.3390/ijms241311217] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/23/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
Inflammatory bowel diseases (IBD) are without cure and troublesome to manage because of the considerable diversity between patients and the lack of reliable biomarkers. Several studies have demonstrated that diet, gut microbiota, genetics and other patient factors are essential for disease occurrence and progression. Understanding the link between these factors is crucial for identifying molecular signatures that identify biomarkers to advance the management of IBD. Recent technological breakthroughs and data integration have fuelled the intensity of this research. This research demonstrates that the effect of diet depends on patient factors and gut microbial activity. It also identifies a range of potential biomarkers for IBD management, including mucosa-derived cytokines, gasdermins and neutrophil extracellular traps, all of which need further evaluation before clinical translation. This review provides an update on cutting-edge research in IBD that aims to improve disease management and patient quality of life.
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Affiliation(s)
- Vibeke Andersen
- Molecular Diagnostic and Clinical Research Unit, University Hospital of Southern Denmark, Institute of Regional Research, University of Southern Denmark, 5000 Odense, Denmark;
- Institute of Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark
| | - Tue B. Bennike
- Molecular Diagnostic and Clinical Research Unit, University Hospital of Southern Denmark, Institute of Regional Research, University of Southern Denmark, 5000 Odense, Denmark;
- Medical Microbiology and Immunology, Department of Health Science and Technology, Aalborg University, 9000 Aalborg, Denmark
| | - Corinna Bang
- Institute for Clinical Molecular Biology, Christian-Albrecht’s University, 24105 Kiel, Germany;
| | - John D. Rioux
- Department of Medicine, Université de Montréal, Montreal, QC H3C 3J7, Canada; (J.D.R.); (I.H.-M.)
- Montreal Heart Institute Research Institute, Montreal, QC H1T 1C8, Canada
| | - Isabelle Hébert-Milette
- Department of Medicine, Université de Montréal, Montreal, QC H3C 3J7, Canada; (J.D.R.); (I.H.-M.)
- Montreal Heart Institute Research Institute, Montreal, QC H1T 1C8, Canada
| | - Toshiro Sato
- Department of Gastroenterology, Keio University School of Medicine, Tokyo 160-8582, Japan;
| | - Axel K. Hansen
- Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark;
| | - Ole H. Nielsen
- Department of Gastroenterology, Herlev Hospital, University of Copenhagen, 2730 Herlev, Denmark
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23
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Radoiu C, Govindarajan B, Wang M, Sbrissa D, Cher ML, Chinni SR. A Novel Interaction between Chemokine and Phosphoinositide Signaling in Metastatic Prostate Cancer. MEDICAL RESEARCH ARCHIVES 2023; 11:10.18103/mra.v11i7.1.4020. [PMID: 38239314 PMCID: PMC10795749 DOI: 10.18103/mra.v11i7.1.4020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2024]
Abstract
Prostate cancer commonly metastasizes to bone due to its favorable microenvironment for cell growth and survival. Currently, the standard of care for metastatic prostate cancer is medical castration in conjunction with chemotherapeutic agents and newer anti-androgen/androgen receptor therapies. While these therapies aim to improve the quality of life in patients with advanced disease, resistance to these therapies is inevitable prompting the development of newer therapies to contain disease progression. The CXCL12/CXCR4 axis has previously been shown to be involved in prostate cancer cell homing to bone tissue, and new investigations found a novel interaction of Phosphatidyl Inositol 4 kinase IIIa (PI4KA) downstream of chemokine signaling. PI4KA phosphorylates at the 4th position on phosphatidylinositol (PI), to produce PI4P and is localized to the plasma membrane (PM). At the PM, PI4KA provides precursors for the generation of PI(4,5)P2, and PI(3,4,5)P3 and helps maintain PM identity through the recruitment of lipids and signaling proteins. PI4KA is recruited to the PM through evolutionarily conserved adaptor proteins, and in PC cells, CXCR4 binds with adaptor proteins to recruit PI4KA to the PM. The objective of this review is to summarize our understanding of the role that phosphatidyl inositol lipid messengers in cancer cells.
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Affiliation(s)
- Codrut Radoiu
- Department of Urology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Barani Govindarajan
- Department of Urology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Michael Wang
- Department of Urology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Diego Sbrissa
- Department of Urology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Michael L. Cher
- Department of Urology, Wayne State University School of Medicine, Detroit, MI 48201, USA
- Department of Pathology, Wayne State University School of Medicine, Detroit, MI 48201, USA
- Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Sreenivasa R. Chinni
- Department of Urology, Wayne State University School of Medicine, Detroit, MI 48201, USA
- Department of Pathology, Wayne State University School of Medicine, Detroit, MI 48201, USA
- Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201, USA
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24
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Bura A, Čabrijan S, Đurić I, Bruketa T, Jurak Begonja A. A Plethora of Functions Condensed into Tiny Phospholipids: The Story of PI4P and PI(4,5)P 2. Cells 2023; 12:1411. [PMID: 37408244 DOI: 10.3390/cells12101411] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 07/07/2023] Open
Abstract
Phosphoinositides (PIs) are small, phosphorylated lipids that serve many functions in the cell. They regulate endo- and exocytosis, vesicular trafficking, actin reorganization, and cell mobility, and they act as signaling molecules. The most abundant PIs in the cell are phosphatidylinositol-4-monophosphate (PI4P) and phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2]. PI4P is mostly localized at the Golgi apparatus where it regulates the anterograde trafficking from the Golgi apparatus to the plasma membrane (PM), but it also localizes at the PM. On the other hand, the main localization site of PI(4,5)P2 is the PM where it regulates the formation of endocytic vesicles. The levels of PIs are regulated by many kinases and phosphatases. Four main kinases phosphorylate the precursor molecule phosphatidylinositol into PI4P, divided into two classes (PI4KIIα, PI4KIIβ, PI4KIIIα, and PI4KIIIβ), and three main kinases phosphorylate PI4P to form PI(4,5)P2 (PI4P5KIα, PI4P5KIβ, and PI4P5KIγ). In this review, we discuss the localization and function of the kinases that produce PI4P and PI(4,5)P2, as well as the localization and function of their product molecules with an overview of tools for the detection of these PIs.
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Affiliation(s)
- Ana Bura
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Sara Čabrijan
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Iris Đurić
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Tea Bruketa
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Antonija Jurak Begonja
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
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25
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Bura A, Čabrijan S, Bertović I, Jurak Begonja A. The intracellular and plasma membrane pools of phosphatidylinositol-4-monophosphate control megakaryocyte maturation and proplatelet formation. Res Pract Thromb Haemost 2023; 7:100169. [PMID: 37304829 PMCID: PMC10251075 DOI: 10.1016/j.rpth.2023.100169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 03/12/2023] [Accepted: 04/03/2023] [Indexed: 06/13/2023] Open
Abstract
Background Megakaryocytes (MKs) develop from hematopoietic stem cells after stimulation by the cytokine thrombopoietin. During megakaryopoiesis, MKs enlarge, undergo the process of endomitosis, and develop intracellular membranes (demarcation membrane system, DMS). During DMS formation, there is active transport of proteins, lipids, and membranes from the Golgi apparatus to the DMS. The most important phosphoinositide that controls anterograde transport from the Golgi apparatus to the plasma membrane (PM) is phosphatidylinositol-4-monophosphate (PI4P), whose levels are controlled by suppressor of actin mutations 1-like protein (Sac1) phosphatase at the Golgi and endoplasmic reticulum. Objectives Here we investigated the role of Sac1 and PI4P in megakaryopoiesis. Methods We analyzed Sac1 and PI4P localization in primary MKs derived from fetal liver or bone marrow and in the DAMI cell line by immunofluorescence. The intracellular and PM pools of PI4P in primary MKs were modulated by expression of Sac1 constructs from retroviral vector and inhibition of PI4 kinase IIIα, respectively. Results We showed that in primary mouse MKs, PI4P is mostly found in the Golgi apparatus and the PM in immature MKs, while in mature MKs, it is found in the cell periphery and at the PM. The exogenous expression of wild-type but not C389S mutant (catalytically dead) Sac1 results in the perinuclear retention of the Golgi apparatus resembling immature MKs, with decreased ability to form proplatelets. The pharmacologic inhibition of PI4P production specifically at the PM also resulted in a significant decrease in MKs that form proplatelets. Conclusion These results indicate that both intracellular and PM pools of PI4P mediate MK maturation and proplatelet formation.
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Affiliation(s)
| | | | | | - Antonija Jurak Begonja
- Correspondence Antonija Jurak Begonja, University of Rijeka, Department of Biotechnology, Laboratory of hematopoiesis, R. Matejcic 2, 51 000 Rijeka, Croatia. @JurakBegonja
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26
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Ivanova A, Atakpa-Adaji P. Phosphatidylinositol 4,5-bisphosphate and calcium at ER-PM junctions - Complex interplay of simple messengers. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119475. [PMID: 37098393 DOI: 10.1016/j.bbamcr.2023.119475] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 03/05/2023] [Accepted: 04/03/2023] [Indexed: 04/27/2023]
Abstract
Endoplasmic reticulum-plasma membrane contact sites (ER-PM MCS) are a specialised domain involved in the control of Ca2+ dynamics and various Ca2+-dependent cellular processes. Intracellular Ca2+ signals are broadly supported by Ca2+ release from intracellular Ca2+ channels such as inositol 1,4,5-trisphosphate receptors (IP3Rs) and subsequent store-operated Ca2+ entry (SOCE) across the PM to replenish store content. IP3Rs sit in close proximity to the PM where they can easily access newly synthesised IP3, interact with binding partners such as actin, and localise adjacent to ER-PM MCS populated by the SOCE machinery, STIM1-2 and Orai1-3, to possibly form a locally regulated unit of Ca2+ influx. PtdIns(4,5)P2 is a multiplex regulator of Ca2+ signalling at the ER-PM MCS interacting with multiple proteins at these junctions such as actin and STIM1, whilst also being consumed as a substrate for phospholipase C to produce IP3 in response to extracellular stimuli. In this review, we consider the mechanisms regulating the synthesis and turnover of PtdIns(4,5)P2 via the phosphoinositide cycle and its significance for sustained signalling at the ER-PM MCS. Furthermore, we highlight recent insights into the role of PtdIns(4,5)P2 in the spatiotemporal organization of signalling at ER-PM junctions and raise outstanding questions on how this multi-faceted regulation occurs.
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Affiliation(s)
- Adelina Ivanova
- Department of Pharmacology, Tennis Court Road, Cambridge CB2 1PD, UK.
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27
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Cohen HA, Zomot E, Nataniel T, Militsin R, Palty R. The SOAR of STIM1 interacts with plasma membrane lipids to form ER-PM contact sites. Cell Rep 2023; 42:112238. [PMID: 36906853 DOI: 10.1016/j.celrep.2023.112238] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 01/15/2023] [Accepted: 02/23/2023] [Indexed: 03/12/2023] Open
Abstract
Depletion of Ca2+ from the endoplasmic reticulum (ER) causes the ER Ca2+ sensor STIM1 to form membrane contact sites (MCSs) with the plasma membrane (PM). At the ER-PM MCS, STIM1 binds to Orai channels to induce cellular Ca2+ entry. The prevailing view of this sequential process is that STIM1 interacts with the PM and with Orai1 using two separate modules: a C-terminal polybasic domain (PBD) for the interaction with PM phosphoinositides and the STIM-Orai activation region (SOAR) for the interaction with Orai channels. Here, using electron and fluorescence microscopy and protein-lipid interaction assays, we show that oligomerization of the SOAR promotes direct interaction with PM phosphoinositides to trap STIM1 at ER-PM MCSs. The interaction depends on a cluster of conserved lysine residues within the SOAR and is co-regulated by the STIM1 coil-coiled 1 and inactivation domains. Collectively, our findings uncover a molecular mechanism for formation and regulation of ER-PM MCSs by STIM1.
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Affiliation(s)
- Hadas Achildiev Cohen
- Department of Biochemistry, Technion Integrated Cancer Center, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Elia Zomot
- Department of Biochemistry, Technion Integrated Cancer Center, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Tomer Nataniel
- Department of Biochemistry, Technion Integrated Cancer Center, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Ruslana Militsin
- Department of Biochemistry, Technion Integrated Cancer Center, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel
| | - Raz Palty
- Department of Biochemistry, Technion Integrated Cancer Center, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa 31096, Israel.
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McPhail JA, Burke JE. Molecular mechanisms of PI4K regulation and their involvement in viral replication. Traffic 2023; 24:131-145. [PMID: 35579216 DOI: 10.1111/tra.12841] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/07/2022] [Accepted: 03/30/2022] [Indexed: 11/28/2022]
Abstract
Lipid phosphoinositides are master signaling molecules in eukaryotic cells and key markers of organelle identity. Because of these important roles, the kinases and phosphatases that generate phosphoinositides must be tightly regulated. Viruses can manipulate this regulation, with the Type III phosphatidylinositol 4-kinases (PI4KA and PI4KB) being hijacked by many RNA viruses to mediate their intracellular replication through the formation of phosphatidylinositol 4-phosphate (PI4P)-enriched replication organelles (ROs). Different viruses have evolved unique approaches toward activating PI4K enzymes to form ROs, through both direct binding of PI4Ks and modulation of PI4K accessory proteins. This review will focus on PI4KA and PI4KB and discuss their roles in signaling, functions in membrane trafficking and manipulation by viruses. Our focus will be the molecular basis for how PI4KA and PI4KB are activated by both protein-binding partners and post-translational modifications, with an emphasis on understanding the different molecular mechanisms viruses have evolved to usurp PI4Ks. We will also discuss the chemical tools available to study the role of PI4Ks in viral infection.
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Affiliation(s)
- Jacob A McPhail
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada.,Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia, Canada
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29
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Govindarajan B, Sbrissa D, Pressprich M, Kim S, Vaishampayan U, Cher ML, Chinni S. Adaptor proteins mediate CXCR4 and PI4KA crosstalk in prostate cancer cells and the significance of PI4KA in bone tumor growth. RESEARCH SQUARE 2023:rs.3.rs-2590830. [PMID: 36865146 PMCID: PMC9980273 DOI: 10.21203/rs.3.rs-2590830/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The chemokine receptor, CXCR4 signaling regulates cell growth, invasion, and metastasis to the bone-marrow niche in prostate cancer (PCa). Previously, we established that CXCR4 interacts with phosphatidylinositol 4-kinase IIIα (PI4KIIIα encoded by PI4KA) through its adaptor proteins and PI4KA overexpressed in the PCa metastasis. To further characterize how the CXCR4-PI4KIIIα axis promotes PCa metastasis, here we identify CXCR4 binds to PI4KIIIα adaptor proteins TTC7 and this interaction induce plasma membrane PI4P production in prostate cancer cells. Inhibiting PI4KIIIα or TTC7 reduces plasma membrane PI4P production, cellular invasion, and bone tumor growth. Using metastatic biopsy sequencing, we found PI4KA expression in tumors correlated with overall survival and contributes to immunosuppressive bone tumor microenvironment through preferentially enriching non-activated and immunosuppressive macrophage populations. Altogether we have characterized the chemokine signaling axis through CXCR4-PI4KIIIα interaction contributing to the growth of prostate cancer bone metastasis.
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30
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Zandl-Lang M, Plecko B, Köfeler H. Lipidomics-Paving the Road towards Better Insight and Precision Medicine in Rare Metabolic Diseases. Int J Mol Sci 2023; 24:ijms24021709. [PMID: 36675224 PMCID: PMC9866746 DOI: 10.3390/ijms24021709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Even though the application of Next-Generation Sequencing (NGS) has significantly facilitated the identification of disease-associated mutations, the diagnostic rate of rare diseases is still below 50%. This causes a diagnostic odyssey and prevents specific treatment, as well as genetic counseling for further family planning. Increasing the diagnostic rate and reducing the time to diagnosis in children with unclear disease are crucial for a better patient outcome and improvement of quality of life. In many cases, NGS reveals variants of unknown significance (VUS) that need further investigations. The delineation of novel (lipid) biomarkers is not only crucial to prove the pathogenicity of VUS, but provides surrogate parameters for the monitoring of disease progression and therapeutic interventions. Lipids are essential organic compounds in living organisms, serving as building blocks for cellular membranes, energy storage and signaling molecules. Among other disorders, an imbalance in lipid homeostasis can lead to chronic inflammation, vascular dysfunction and neurodegenerative diseases. Therefore, analyzing lipids in biological samples provides great insight into the underlying functional role of lipids in healthy and disease statuses. The method of choice for lipid analysis and/or huge assemblies of lipids (=lipidome) is mass spectrometry due to its high sensitivity and specificity. Due to the inherent chemical complexity of the lipidome and the consequent challenges associated with analyzing it, progress in the field of lipidomics has lagged behind other omics disciplines. However, compared to the previous decade, the output of publications on lipidomics has increased more than 17-fold within the last decade and has, therefore, become one of the fastest-growing research fields. Combining multiple omics approaches will provide a unique and efficient tool for determining pathogenicity of VUS at the functional level, and thereby identifying rare, as well as novel, genetic disorders by molecular techniques and biochemical analyses.
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Affiliation(s)
- Martina Zandl-Lang
- Division of General Pediatrics, Department of Pediatrics and Adolescent Medicine, Medical University of Graz, 8036 Graz, Austria
| | - Barbara Plecko
- Division of General Pediatrics, Department of Pediatrics and Adolescent Medicine, Medical University of Graz, 8036 Graz, Austria
| | - Harald Köfeler
- Core Facility Mass Spectrometry, ZMF, Medical University of Graz, 8036 Graz, Austria
- Correspondence:
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Balla T, Gulyas G, Mandal A, Alvarez-Prats A, Niu Y, Kim YJ, Pemberton J. Roles of Phosphatidylinositol 4-Phosphorylation in Non-vesicular Cholesterol Trafficking. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:327-352. [PMID: 36988887 PMCID: PMC11135459 DOI: 10.1007/978-3-031-21547-6_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Cholesterol (Chol) is an essential component of all eukaryotic cell membranes that affects the function of numerous peripheral as well as integral membrane proteins. Chol is synthesized in the ER, but it is selectively enriched within the plasma membrane (PM) and other endomembranes, which requires Chol to cross the aqueous phase of the cytoplasm. In addition to the classical vesicular trafficking pathways that are known to facilitate the bulk transport of membrane intermediates, Chol is also transported via non-vesicular lipid transfer proteins that work primarily within specialized membrane contact sites. Some of these transport pathways work against established concentration gradients and hence require energy. Recent studies highlight the unique role of phosphoinositides (PPIns), and phosphatidylinositol 4-phosphate (PI4P) in particular, for the control of non-vesicular Chol transport. In this chapter, we will review the emerging connection between Chol, PPIns, and lipid transfer proteins that include the important family of oxysterol-binding protein related proteins, or ORPs.
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Affiliation(s)
- Tamas Balla
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, USA.
| | | | - Amrita Mandal
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, USA
| | - Alejandro Alvarez-Prats
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, USA
| | | | - Yeun Ju Kim
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, USA
| | - Joshua Pemberton
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, USA
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32
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Dickson EJ. Role of Lysosomal Cholesterol in Regulating PI(4,5)P 2-Dependent Ion Channel Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:193-215. [PMID: 36988882 DOI: 10.1007/978-3-031-21547-6_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Lysosomes are central regulators of cellular growth and signaling. Once considered the acidic garbage can of the cell, their ever-expanding repertoire of functions include the regulation of cell growth, gene regulation, metabolic signaling, cell migration, and cell death. In this chapter, we detail how another of the lysosome's crucial roles, cholesterol transport, plays a vital role in the control of ion channel function and neuronal excitability through its ability to influence the abundance of the plasma membrane signaling lipid phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). This chapter will introduce the biosynthetic pathways of cholesterol and PI(4,5)P2, discuss the molecular mechanisms through which each lipid distinctly regulates ion channels, and consider the interdependence of these lipids in the control of ion channel function.
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Affiliation(s)
- Eamonn J Dickson
- Department of Physiology and Membrane Biology, University of California, Davis, CA, USA.
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Pacheco J, Bohórquez-Hernández A, Méndez-Acevedo KM, Sampieri A, Vaca L. Roles of Cholesterol and PtdIns(4,5)P 2 in the Regulation of STIM1-Orai1 Channel Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:305-326. [PMID: 36988886 DOI: 10.1007/978-3-031-21547-6_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Calcium is one of the most prominent second messengers. It is involved in a wide range of functions at the single-cell level but also in modulating regulatory mechanisms in the entire organism. One process mediating calcium signaling involves hydrolysis of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) by the phospholipase-C (PLC). Thus, calcium and PtdIns(4,5)P2 are intimately intertwined two second-messenger cascades that often depend on each other. Another relevant lipid associated with calcium signaling is cholesterol. Both PtdIns(4,5)P2 and cholesterol play key roles in the formation and maintenance of specialized signaling nanodomains known as lipid rafts. Lipid rafts are particularly important in calcium signaling by concentrating and localizing calcium channels such as the Orai1 channel. Depletion of internal calcium stores is initiated by the production of inositol-1,4,5-trisphosphate (IP3). Calcium depletion from the ER induces the oligomerization of STIM1, which binds Orai1 and initiates calcium influx into the cell. In the present review, we analyzed the complex interactions between cholesterol, PtdIns(4,5)P2, and the complex formed by the Orai1 channel and the signaling molecule STIM1. We explore some of the complex mechanisms governing calcium homeostasis and phospholipid metabolism, as well as the interaction between these two apparently independent signaling cascades.
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Affiliation(s)
- Jonathan Pacheco
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Kevin M Méndez-Acevedo
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- ZHK, German Center for Cardiovascular Research, Partner Site, Berlin, Germany
| | - Alicia Sampieri
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| | - Luis Vaca
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México.
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Barkat K. Prenatal imaging and whole-exome sequencing identify novel tetratricopeptide repeat domain 7A mutation in foetus with gastrointestinal atresia: a case report. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2022. [DOI: 10.1186/s43055-022-00807-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Tetratricopeptide repeat domain 7A (TTC7A, chromosome 2p21) is a highly conserved structural motif essential for multiprotein scaffolding and cell survival. Fewer than 60 cases of TTC7A deficiency have been reported globally. It produces multisystemic disease phenotypes which are lethal in two-thirds of patients, with a median survival age of 12 months. It is predominantly detected postnatally, often rendering medical and surgical interventions futile.
Case presentation
We report the antenatal sonographic and magnetic resonance imaging characteristics of a novel phenotype of TTC7A-deficiency presenting with gastrointestinal atresia. This has never been previously documented. The diagnosis was confirmed via whole-exome next-generation sequencing, thus facilitating prompt initiation of management and prolonging viability.
Conclusions
Novel insight into the prenatal morphological characteristics of TTC7A-deficiency phenotypes expands knowledge of this rare condition. Furthermore, antenatal recognition facilitates targeted investigation, genetic counselling, and earlier multidisciplinary intervention to prolong viability of this predominantly lethal condition.
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35
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Burke JE, Triscott J, Emerling BM, Hammond GRV. Beyond PI3Ks: targeting phosphoinositide kinases in disease. Nat Rev Drug Discov 2022; 22:357-386. [PMID: 36376561 PMCID: PMC9663198 DOI: 10.1038/s41573-022-00582-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2022] [Indexed: 11/16/2022]
Abstract
Lipid phosphoinositides are master regulators of almost all aspects of a cell's life and death and are generated by the tightly regulated activity of phosphoinositide kinases. Although extensive efforts have focused on drugging class I phosphoinositide 3-kinases (PI3Ks), recent years have revealed opportunities for targeting almost all phosphoinositide kinases in human diseases, including cancer, immunodeficiencies, viral infection and neurodegenerative disease. This has led to widespread efforts in the clinical development of potent and selective inhibitors of phosphoinositide kinases. This Review summarizes our current understanding of the molecular basis for the involvement of phosphoinositide kinases in disease and assesses the preclinical and clinical development of phosphoinositide kinase inhibitors.
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Affiliation(s)
- John E. Burke
- grid.143640.40000 0004 1936 9465Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia Canada ,grid.17091.3e0000 0001 2288 9830Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia Canada
| | - Joanna Triscott
- grid.5734.50000 0001 0726 5157Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Brooke M. Emerling
- grid.479509.60000 0001 0163 8573Sanford Burnham Prebys, La Jolla, CA USA
| | - Gerald R. V. Hammond
- grid.21925.3d0000 0004 1936 9000Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA USA
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36
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Zhang K, Kang L, Zhang H, Bai L, Pang H, Liu Q, Zhang X, Chen D, Yu H, Lv Y, Gao M, Liu Y, Gai Z, Wang D, Li X. A synonymous mutation in PI4KA impacts the transcription and translation process of gene expression. Front Immunol 2022; 13:987666. [DOI: 10.3389/fimmu.2022.987666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Phosphatidylinositol-4-kinase alpha (PI4KIIIα), encoded by the PI4KA gene, can synthesize phosphatidylinositol-4-phosphate (PI-4-P), which serves as a specific membrane marker and is instrumental in signal transduction. PI4KA mutations can cause autosomal recessive diseases involving neurological, intestinal, and immunological conditions (OMIM:619621, 616531, 619708). We detected sepsis, severe diarrhea, and decreased immunoglobulin levels in one neonate. Two novel compound heterozygous mutations, c.5846T>C (p.Leu1949Pro) and c.3453C>T (p.Gly1151=), were identified in the neonate from the father and the mother, respectively. Sanger sequencing and reverse transcription polymerase chain reaction (RT-PCR) for peripheral blood and minigene splicing assays showed a deletion of five bases (GTGAG) with the c.3453C>T variant at the mRNA level, which could result in a truncated protein (p.Gly1151GlyfsTer17). The missense mutation c.5846T>C (p.Leu1949Pro) kinase activity was measured, and little or no catalytic activity was detected. According to the clinical characteristics and gene mutations with functional verification, our pediatricians diagnosed the child with a combined immunodeficiency and intestinal disorder close to gastrointestinal defects and immunodeficiency syndrome 2 (GIDID2; OMIM: 619708). Medicines such as immunomodulators are prescribed to balance immune dysregulation. This study is the first report of a synonymous mutation in the PI4KA gene that influences alternative splicing. Our findings expand the mutation spectrum leading to PI4KIIIa deficiency-related diseases and provide exact information for genetic counseling.
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37
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Hippo pathway regulation by phosphatidylinositol transfer protein and phosphoinositides. Nat Chem Biol 2022; 18:1076-1086. [PMID: 35788180 DOI: 10.1038/s41589-022-01061-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 05/12/2022] [Indexed: 12/30/2022]
Abstract
The Hippo pathway plays a key role in development, organ size control and tissue homeostasis, and its dysregulation contributes to cancer. The LATS tumor suppressor kinases phosphorylate and inhibit the YAP/TAZ transcriptional co-activators to suppress gene expression and cell growth. Through a screen of marine natural products, we identified microcolin B (MCB) as a Hippo activator that preferentially kills YAP-dependent cancer cells. Structure-activity optimization yielded more potent MCB analogs, which led to the identification of phosphatidylinositol transfer proteins α and β (PITPα/β) as the direct molecular targets. We established a critical role of PITPα/β in regulating LATS and YAP. Moreover, we showed that PITPα/β influence the Hippo pathway via plasma membrane phosphatidylinositol-4-phosphate. This study uncovers a previously unrecognized role of PITPα/β in Hippo pathway regulation and as potential cancer therapeutic targets.
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38
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Gulyas G, Korzeniowski MK, Eugenio CEB, Vaca L, Kim YJ, Balla T. LIPID transfer proteins regulate store-operated calcium entry via control of plasma membrane phosphoinositides. Cell Calcium 2022; 106:102631. [PMID: 35853265 PMCID: PMC9444960 DOI: 10.1016/j.ceca.2022.102631] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 06/24/2022] [Accepted: 07/08/2022] [Indexed: 11/27/2022]
Abstract
The ER-resident proteins STIM1 together with the plasma membrane (PM)-localized Orai1 channels constitute the molecular components of the store-operated Ca2+ entry (SOCE) pathway. Prepositioning of STIM1 to the peripheral ER close to the PM ensures its efficient interaction with Orai1 upon a decrease in the ER luminal Ca2+ concentration. The C-terminal polybasic domain of STIM1 has been identified as mediating the interaction with PM phosphoinositides and hence positions the molecule to ER-PM contact sites. Here we show that STIM1 requires PM phosphatidylinositol 4-phosphate (PI4P) for efficient PM interaction. Accordingly, oxysterol binding protein related proteins (ORPs) that work at ER-PM junctions and consume PI4P gradients exert important control over the Ca2+ entry process. These studies reveal an important connection between non-vesicular lipid transport at ER-PM contact sites and regulation of ER Ca2+store refilling.
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Affiliation(s)
- Gergo Gulyas
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Marek K Korzeniowski
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, 20892, USA; Department of Anatomy, Physiology, and Genetics, Uniformed Services University, Bethesda, MD, USA
| | - Carlos Ernesto Bastián Eugenio
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, 20892, USA; Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico City DF, CP, 04510, USA
| | - Luis Vaca
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico City DF, CP, 04510, USA
| | - Yeun Ju Kim
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Tamas Balla
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD, 20892, USA.
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Habib K, Bishayee K, Kang J, Sadra A, Huh SO. RNA Binding Protein Rbms1 Enables Neuronal Differentiation and Radial Migration during Neocortical Development by Binding and Stabilizing the RNA Message for Efr3a. Mol Cells 2022; 45:588-602. [PMID: 35754370 PMCID: PMC9385565 DOI: 10.14348/molcells.2022.0044] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/06/2022] [Accepted: 04/09/2022] [Indexed: 11/27/2022] Open
Abstract
Various RNA-binding proteins (RBPs) are key components in RNA metabolism and contribute to several neurodevelop-mental disorders. To date, only a few of such RBPs have been characterized for their roles in neocortex development. Here, we show that the RBP, Rbms1, is required for radial migration, polarization and differentiation of neuronal progenitors to neurons in the neocortex development. Rbms1 expression is highest in the early development in the developing cortex, with its expression gradually diminishing from embryonic day 13.5 (E13.5) to postnatal day 0 (P0). From in utero electroporation (IUE) experiments when Rbms1 levels are knocked down in neuronal progenitors, their transition from multipolar to bipolar state is delayed and this is accompanied by a delay in radial migration of these cells. Reduced Rbms1 levels in vivo also reduces differentiation as evidenced by a decrease in levels of several differentiation markers, meanwhile having no significant effects on proliferation and cell cycle rates of these cells. As an RNA binding protein, we profiled the RNA binders of Rbms1 by a cross-linked-RIP sequencing assay, followed by quantitative real-time polymerase chain reaction verification and showed that Rbms1 binds and stabilizes the mRNA for Efr3a, a signaling adapter protein. We also demonstrate that ectopic Efr3a can recover the cells from the migration defects due to loss of Rbms1, both in vivo and in vitro migration assays with cultured cells. These imply that one of the functions of Rbms1 involves the stabilization of Efr3a RNA message, required for migration and maturation of neuronal progenitors in radial migration in the developing neocortex.
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Affiliation(s)
- Khadija Habib
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
| | - Kausik Bishayee
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
| | - Jieun Kang
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
| | - Ali Sadra
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
| | - Sung-Oh Huh
- Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea
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An acquired phosphatidylinositol 4-phosphate transport initiates T-cell deterioration and leukemogenesis. Nat Commun 2022; 13:4390. [PMID: 35906240 PMCID: PMC9338045 DOI: 10.1038/s41467-022-32104-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 07/11/2022] [Indexed: 11/28/2022] Open
Abstract
Lipid remodeling is crucial for malignant cell transformation and tumorigenesis, but the precise molecular processes involved and direct evidences for these in vivo remain elusive. Here, we report that oxysterol-binding protein (OSBP)-related protein 4 L (ORP4L) is expressed in adult T-cell leukemia (ATL) cells but not normal T-cells. In ORP4L knock-in T-cells, ORP4L dimerizes with OSBP to control the shuttling of OSBP between the Golgi apparatus and the plasma membrane (PM) as an exchanger of phosphatidylinositol 4-phosphate [PI(4)P]/cholesterol. The PI(4)P arriving at the PM via this transport machinery replenishes phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] and phosphatidylinositol (3,4,5) trisphosphate [PI(3,4,5)P3] biosynthesis, thus contributing to PI3K/AKT hyperactivation and T-cell deterioration in vitro and in vivo. Disruption of ORP4L and OSBP dimerization disables PI(4)P transport and T-cell leukemogenesis. In summary, we identify a non-vesicular lipid transport machinery between Golgi and PM maintaining the oncogenic signaling competence initiating T-cell deterioration and leukemogenesis. The oxysterol-binding protein-related protein 4 (ORP4L) is expressed in T-cell acute lymphoblastic leukemia and is required for leukemogenesis. Here the authors show that ORP4L orchestrates the transport of the phospholipid PI(4)P from Golgi to the plasma membrane, contributing to PI3K/AKT hyperactivation and T-cell leukemogenesis.
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Local synthesis of the phosphatidylinositol-3,4-bisphosphate lipid drives focal adhesion turnover. Dev Cell 2022; 57:1694-1711.e7. [PMID: 35809565 PMCID: PMC7613278 DOI: 10.1016/j.devcel.2022.06.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 03/25/2022] [Accepted: 06/15/2022] [Indexed: 12/30/2022]
Abstract
Focal adhesions are multifunctional organelles that couple cell-matrix adhesion to cytoskeletal force transmission and signaling and to steer cell migration and collective cell behavior. Whereas proteomic changes at focal adhesions are well understood, little is known about signaling lipids in focal adhesion dynamics. Through the characterization of cells from mice with a kinase-inactivating point mutation in the class II PI3K-C2β, we find that generation of the phosphatidylinositol-3,4-bisphosphate (PtdIns(3,4)P2) membrane lipid promotes focal adhesion disassembly in response to changing environmental conditions. We show that reduced growth factor signaling sensed by protein kinase N, an mTORC2 target and effector of RhoA, synergizes with the adhesion disassembly factor DEPDC1B to induce local synthesis of PtdIns(3,4)P2 by PI3K-C2β. PtdIns(3,4)P2 then promotes turnover of RhoA-dependent stress fibers by recruiting the PtdIns(3,4)P2-dependent RhoA-GTPase-activating protein ARAP3. Our findings uncover a pathway by which cessation of growth factor signaling facilitates cell-matrix adhesion disassembly via a phosphoinositide lipid switch.
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42
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EFR3 and phosphatidylinositol 4-kinase IIIα regulate insulin-stimulated glucose transport and GLUT4 dispersal in 3T3-L1 adipocytes. Biosci Rep 2022; 42:231469. [PMID: 35735144 PMCID: PMC9272592 DOI: 10.1042/bsr20221181] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/17/2022] Open
Abstract
Insulin stimulates glucose transport in muscle and adipocytes. This is achieved by regulated delivery of intracellular glucose transporter (GLUT4)-containing vesicles to the plasma membrane where they dock and fuse, resulting in increased cell surface GLUT4 levels. Recent work identified a potential further regulatory step, in which insulin increases the dispersal of GLUT4 in the plasma membrane away from the sites of vesicle fusion. EFR3 is a scaffold protein that facilitates localization of phosphatidylinositol 4-kinase type IIIα to the cell surface. Here we show that knockdown of EFR3 or phosphatidylinositol 4-kinase type IIIα impairs insulin-stimulated glucose transport in adipocytes. Using direct stochastic reconstruction microscopy, we also show that EFR3 knockdown impairs insulin stimulated GLUT4 dispersal in the plasma membrane. We propose that EFR3 plays a previously unidentified role in controlling insulin-stimulated glucose transport by facilitating dispersal of GLUT4 within the plasma membrane.
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Lu J, Dong W, Hammond GR, Hong Y. Hypoxia controls plasma membrane targeting of polarity proteins by dynamic turnover of PI4P and PI(4,5)P2. eLife 2022; 11:79582. [PMID: 35678383 PMCID: PMC9242647 DOI: 10.7554/elife.79582] [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: 04/20/2022] [Accepted: 06/06/2022] [Indexed: 11/17/2022] Open
Abstract
Phosphatidylinositol 4-phosphate (PI4P) and phosphatidylinositol 4,5-biphosphate (PIP2) are key phosphoinositides that determine the identity of the plasma membrane (PM) and regulate numerous key biological events there. To date, mechanisms regulating the homeostasis and dynamic turnover of PM PI4P and PIP2 in response to various physiological conditions and stresses remain to be fully elucidated. Here, we report that hypoxia in Drosophila induces acute and reversible depletion of PM PI4P and PIP2 that severely disrupts the electrostatic PM targeting of multiple polybasic polarity proteins. Genetically encoded ATP sensors confirmed that hypoxia induces acute and reversible reduction of cellular ATP levels which showed a strong real-time correlation with the levels of PM PI4P and PIP2 in cultured cells. By combining genetic manipulations with quantitative imaging assays we showed that PI4KIIIα, as well as Rbo/EFR3 and TTC7 that are essential for targeting PI4KIIIα to PM, are required for maintaining the homeostasis and dynamic turnover of PM PI4P and PIP2 under normoxia and hypoxia. Our results revealed that in cells challenged by energetic stresses triggered by hypoxia, ATP inhibition and possibly ischemia, dramatic turnover of PM PI4P and PIP2 could have profound impact on many cellular processes including electrostatic PM targeting of numerous polybasic proteins.
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Affiliation(s)
- Juan Lu
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, China [CN]
| | - Wei Dong
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, United States
| | - Gerald R Hammond
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, United States
| | - Yang Hong
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, United States
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Jensen JB, Falkenburger BH, Dickson EJ, de la Cruz L, Dai G, Myeong J, Jung SR, Kruse M, Vivas O, Suh BC, Hille B. Biophysical physiology of phosphoinositide rapid dynamics and regulation in living cells. J Gen Physiol 2022; 154:e202113074. [PMID: 35583815 PMCID: PMC9121023 DOI: 10.1085/jgp.202113074] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 04/28/2022] [Indexed: 01/07/2023] Open
Abstract
Phosphoinositide membrane lipids are ubiquitous low-abundance signaling molecules. They direct many physiological processes that involve ion channels, membrane identification, fusion of membrane vesicles, and vesicular endocytosis. Pools of these lipids are continually broken down and refilled in living cells, and the rates of some of these reactions are strongly accelerated by physiological stimuli. Recent biophysical experiments described here measure and model the kinetics and regulation of these lipid signals in intact cells. Rapid on-line monitoring of phosphoinositide metabolism is made possible by optical tools and electrophysiology. The experiments reviewed here reveal that as for other cellular second messengers, the dynamic turnover and lifetimes of membrane phosphoinositides are measured in seconds, controlling and timing rapid physiological responses, and the signaling is under strong metabolic regulation. The underlying mechanisms of this metabolic regulation remain questions for the future.
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Affiliation(s)
- Jill B. Jensen
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | | | - Eamonn J. Dickson
- Department of Physiology and Membrane Biology, University of California, Davis, Davis, CA
| | - Lizbeth de la Cruz
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Gucan Dai
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO
| | - Jongyun Myeong
- Department of Cell Biology and Physiology, Washington University in St. Louis, St. Louis, MO
| | | | - Martin Kruse
- Department of Biology and Program in Neuroscience, Bates College, Lewiston, ME
| | - Oscar Vivas
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Byung-Chang Suh
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Bertil Hille
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
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Supercritical fluid chromatography-mass spectrometry enables simultaneous measurement of all phosphoinositide regioisomers. Commun Chem 2022; 5:61. [PMID: 36697617 PMCID: PMC9814602 DOI: 10.1038/s42004-022-00676-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 04/22/2022] [Indexed: 01/28/2023] Open
Abstract
Phosphoinositide species, differing in phosphorylation at hydroxyls of the inositol head group, play roles in various cellular events. Despite the importance of phosphoinositides, simultaneous quantification of individual phosphoinositide species is difficult using conventional methods. Here we developed a supercritical fluid chromatography-mass spectrometry method that can quantify the molecular species of all seven phosphoinositide regioisomers. We used this method to analyze (1) profiles of phosphoinositide species in mouse tissues, (2) the effect of lysophosphatidylinositol acyltransferase 1-depletion on phosphoinositide acyl-chain composition in cultured cells, and (3) the molecular species of phosphatidylinositol-3-phosphate produced during the induction of autophagy. Although further improvement is needed for the absolute quantification of minor phosphoinositide regioisomers in biological samples, our method should clarify the physiological and pathological roles of phosphoinositide regioisomers at the molecular species level.
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46
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Kumari A, Ghosh A, Kolay S, Raghu P. Septins tune lipid kinase activity and PI(4,5)P 2 turnover during G-protein–coupled PLC signalling in vivo. Life Sci Alliance 2022; 5:5/6/e202101293. [PMID: 35277468 PMCID: PMC8921834 DOI: 10.26508/lsa.202101293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/23/2022] [Accepted: 02/25/2022] [Indexed: 11/24/2022] Open
Abstract
Phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] hydrolysis by phospholipase C (PLC) is a conserved mechanism of signalling. Given the low abundance of PI(4,5)P2, its hydrolysis needs to be coupled to resynthesis to ensure continued PLC activity; however, the mechanism by which depletion is coupled to resynthesis remains unknown. PI(4,5)P2 synthesis is catalyzed by the phosphorylation of phosphatidylinositol 4 phosphate (PI4P) by phosphatidylinositol 4 phosphate 5 kinase (PIP5K). In Drosophila photoreceptors, photon absorption is transduced into PLC activity and during this process, PI(4,5)P2 is resynthesized by a PIP5K. However, the mechanism by which PIP5K activity is coupled to PI(4,5)P2 hydrolysis is unknown. In this study, we identify a unique isoform dPIP5KL, that is both necessary and sufficient to mediate PI(4,5)P2 synthesis during phototransduction. Depletion of PNUT, a non-redundant subunit of the septin family, enhances dPIP5KL activity in vitro and PI(4,5)P2 resynthesis in vivo; co-depletion of dPIP5KL reverses the enhanced rate of PI(4,5)P2 resynthesis in vivo. Thus, our work defines a septin-mediated mechanism through which PIP5K activity is coupled to PLC-mediated PI(4,5)P2 hydrolysis.
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Affiliation(s)
- Aastha Kumari
- National Centre for Biological Sciences, TIFR-GKVK Campus, Bengaluru, India
| | - Avishek Ghosh
- National Centre for Biological Sciences, TIFR-GKVK Campus, Bengaluru, India
- Department of Surgery, Vascular Biology Program, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Sourav Kolay
- National Centre for Biological Sciences, TIFR-GKVK Campus, Bengaluru, India
- UT Southwestern Medical Center, Dallas, TX, USA
| | - Padinjat Raghu
- National Centre for Biological Sciences, TIFR-GKVK Campus, Bengaluru, India
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de la Cruz L, Kushmerick C, Sullivan JM, Kruse M, Vivas O. Hippocampal neurons maintain a large PtdIns(4)P pool that results in faster PtdIns(4,5)P2 synthesis. J Gen Physiol 2022; 154:213016. [PMID: 35179558 PMCID: PMC8906353 DOI: 10.1085/jgp.202113001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 01/01/2022] [Accepted: 01/24/2022] [Indexed: 12/24/2022] Open
Abstract
PtdIns(4,5)P2 is a signaling lipid central to the regulation of multiple cellular functions. It remains unknown how PtdIns(4,5)P2 fulfills various functions in different cell types, such as regulating neuronal excitability, synaptic release, and astrocytic function. Here, we compared the dynamics of PtdIns(4,5)P2 synthesis in hippocampal neurons and astrocytes with the kidney-derived tsA201 cell line. The experimental approach was to (1) measure the abundance and rate of PtdIns(4,5)P2 synthesis and precursors using specific biosensors, (2) measure the levels of PtdIns(4,5)P2 and its precursors using mass spectrometry, and (3) use a mathematical model to compare the metabolism of PtdIns(4,5)P2 in cell types with different proportions of phosphoinositides. The rate of PtdIns(4,5)P2 resynthesis in hippocampal neurons after depletion by cholinergic or glutamatergic stimulation was three times faster than for tsA201 cells. In tsA201 cells, resynthesis of PtdIns(4,5)P2 was dependent on the enzyme PI4K. In contrast, in hippocampal neurons, the resynthesis rate of PtdIns(4,5)P2 was insensitive to the inhibition of PI4K, indicating that it does not require de novo synthesis of the precursor PtdIns(4)P. Measurement of phosphoinositide abundance indicated a larger pool of PtdIns(4)P, suggesting that hippocampal neurons maintain sufficient precursor to restore PtdIns(4,5)P2 levels. Quantitative modeling indicates that the measured differences in PtdIns(4)P pool size and higher activity of PI4K can account for the experimental findings and indicates that high PI4K activity prevents depletion of PtdIns(4)P. We further show that the resynthesis of PtdIns(4,5)P2 is faster in neurons than astrocytes, providing context to the relevance of cell type–specific mechanisms to sustain PtdIns(4,5)P2 levels.
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Affiliation(s)
- Lizbeth de la Cruz
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Christopher Kushmerick
- Department of Physiology and Biophysics, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Jane M Sullivan
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Martin Kruse
- Department of Biology and Program in Neuroscience, Bates College, Lewiston, ME
| | - Oscar Vivas
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
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Guo Z, Jiang CH, Tong C, Yang Y, Wang Z, Lam SM, Wang D, Li R, Shui G, Shi YS, Liu JJ. Activity-dependent PI4P synthesis by PI4KIIIα regulates long-term synaptic potentiation. Cell Rep 2022; 38:110452. [PMID: 35235793 DOI: 10.1016/j.celrep.2022.110452] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 12/30/2021] [Accepted: 02/07/2022] [Indexed: 01/11/2023] Open
Abstract
Phosphatidylinositol 4-phosphate (PI4P) is a low abundant phospholipid with important roles in lipid transport and membrane trafficking. However, little is known of its metabolism and function in neurons. Here, we investigate its subcellular distribution and functional roles in dendrites of rodent hippocampal neurons during resting state and long-term synaptic potentiation (LTP). We show that neural activity causes dynamic reversible changes in PI4P metabolism in dendrites. Upon LTP induction, PI4KIIIα, a type III phosphatidylinositol 4-kinase, localizes to the dendritic plasma membrane (PM) in a calcium-dependent manner and causes substantial increase in the levels of PI4P. Acute inhibition of PI4KIIIα activity abolishes trafficking of the AMPA-type glutamate receptor to the PM during LTP induction, and silencing of PI4KIIIα expression in the hippocampal CA1 region causes severe impairment of LTP and long-term memory. Collectively, our results identify an essential role for PI4KIIIα-dependent PI4P synthesis in synaptic plasticity of central nervous system neurons.
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Affiliation(s)
- Zhenzhen Guo
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100039, China
| | - Chao-Hua Jiang
- State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center of Nanjing University, Nanjing 210061, China
| | - Chunfang Tong
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Yanrui Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Zehua Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100039, China
| | - Sin Man Lam
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Dou Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Rui Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100039, China
| | - Guanghou Shui
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Yun Stone Shi
- State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center of Nanjing University, Nanjing 210061, China
| | - Jia-Jia Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100039, China.
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49
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Batrouni AG, Bag N, Phan HT, Baird BA, Baskin JM. A palmitoylation code controls PI4KIIIα complex formation and PI(4,5)P2 homeostasis at the plasma membrane. J Cell Sci 2022; 135:272297. [PMID: 34569608 DOI: 10.1242/jcs.259365] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 09/14/2021] [Indexed: 12/12/2022] Open
Abstract
Phosphatidylinositol 4-kinase IIIα (PI4KIIIα) is the major enzyme responsible for generating phosphatidylinositol (4)-phosphate [PI(4)P] at the plasma membrane. This lipid kinase forms two multicomponent complexes, both including a palmitoylated anchor, EFR3. Whereas both PI4KIIIα complexes support production of PI(4)P, the distinct functions of each complex and mechanisms underlying the interplay between them remain unknown. Here, we present roles for differential palmitoylation patterns within a tri-cysteine motif in EFR3B (Cys5, Cys7 and Cys8) in controlling the distribution of PI4KIIIα between these two complexes at the plasma membrane and corresponding functions in phosphoinositide homeostasis. Spacing of palmitoyl groups within three doubly palmitoylated EFR3B 'lipoforms' affects both interactions between EFR3B and TMEM150A, a transmembrane protein governing formation of a PI4KIIIα complex functioning in rapid phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] resynthesis following phospholipase C signaling, and EFR3B partitioning within liquid-ordered and -disordered regions of the plasma membrane. This work identifies a palmitoylation code involved in controlling protein-protein and protein-lipid interactions that affect a plasma membrane-resident lipid biosynthetic pathway.
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Affiliation(s)
- Alex G Batrouni
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.,Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, NY 14853, USA
| | - Nirmalya Bag
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Henry T Phan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Barbara A Baird
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Jeremy M Baskin
- Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, NY 14853, USA.,Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
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50
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Maltan L, Andova AM, Derler I. The Role of Lipids in CRAC Channel Function. Biomolecules 2022; 12:biom12030352. [PMID: 35327543 PMCID: PMC8944985 DOI: 10.3390/biom12030352] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/12/2022] [Accepted: 02/20/2022] [Indexed: 11/28/2022] Open
Abstract
The composition and dynamics of the lipid membrane define the physical properties of the bilayer and consequently affect the function of the incorporated membrane transporters, which also applies for the prominent Ca2+ release-activated Ca2+ ion channel (CRAC). This channel is activated by receptor-induced Ca2+ store depletion of the endoplasmic reticulum (ER) and consists of two transmembrane proteins, STIM1 and Orai1. STIM1 is anchored in the ER membrane and senses changes in the ER luminal Ca2+ concentration. Orai1 is the Ca2+-selective, pore-forming CRAC channel component located in the plasma membrane (PM). Ca2+ store-depletion of the ER triggers activation of STIM1 proteins, which subsequently leads to a conformational change and oligomerization of STIM1 and its coupling to as well as activation of Orai1 channels at the ER-PM contact sites. Although STIM1 and Orai1 are sufficient for CRAC channel activation, their efficient activation and deactivation is fine-tuned by a variety of lipids and lipid- and/or ER-PM junction-dependent accessory proteins. The underlying mechanisms for lipid-mediated CRAC channel modulation as well as the still open questions, are presented in this review.
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