1
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Kofuji S, Wolfe K, Sumita K, Kageyama S, Yoshino H, Hirota Y, Ogawa-Iio A, Kanoh H, Sasaki M, Kofuji K, Davis MI, Pragani R, Shen M, Boxer MB, Nakatsu F, Nigorikawa K, Sasaki T, Takeuchi K, Senda T, Kim SM, Edinger AL, Simeonov A, Sasaki AT. A high dose KRP203 induces cytoplasmic vacuoles associated with altered phosphoinositide segregation and endosome expansion. Biochem Biophys Res Commun 2024; 718:149981. [PMID: 38735134 DOI: 10.1016/j.bbrc.2024.149981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 04/22/2024] [Indexed: 05/14/2024]
Abstract
In animal cells, vacuoles are absent, but can be induced by diseases and drugs. While phosphoinositides are critical for membrane trafficking, their role in the formation of these vacuoles remains unclear. The immunosuppressive KRP203/Mocravimod, which antagonizes sphingosine-1-phosphate receptors, has been identified as having novel multimodal activity against phosphoinositide kinases. However, the impact of this novel KRP203 activity is unknown. Here, we show that KRP203 disrupts the spatial organization of phosphoinositides and induces extensive vacuolization in tumor cells and immortalized fibroblasts. The KRP203-induced vacuoles are primarily from endosomes, and augmented by inhibition of PIKFYVE and VPS34. Conversely, overexpression of PTEN decreased KRP203-induced vacuole formation. Furthermore, V-ATPase inhibition completely blunted KRP203-induced vacuolization, pointing to a critical requirement of the endosomal maturation process. Importantly, nearly a half of KRP203-induced vacuoles are significantly decorated with PI4P, a phosphoinositide typically enriched at the plasma membrane and Golgi. These results suggest a model that noncanonical spatial reorganization of phosphoinositides by KRP203 alters the endosomal maturation process, leading to vacuolization. Taken together, this study reveals a previously unrecognized bioactivity of KRP203 as a vacuole-inducing agent and its unique mechanism of phosphoinositide modulation, providing a new insight of phosphoinositide regulation into vacuolization-associated diseases and their molecular pathologies.
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Affiliation(s)
- Satoshi Kofuji
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA; Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, 113-8510, Japan
| | - Kara Wolfe
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Kazutaka Sumita
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA; Department of Endovascular Surgery, Tokyo Medical and Dental University, Tokyo, 113-8510, Japan
| | - Shun Kageyama
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, 997-0052, Japan
| | - Hirofumi Yoshino
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Yoshihisa Hirota
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA; Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Minuma-ku, Saitama, 337-8570, Japan
| | - Aki Ogawa-Iio
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA; Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Minuma-ku, Saitama, 337-8570, Japan
| | - Hirotaka Kanoh
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, 997-0052, Japan
| | - Mika Sasaki
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Kaori Kofuji
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Mindy I Davis
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Rajan Pragani
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Matthew B Boxer
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Fubito Nakatsu
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata, Japan
| | - Kiyomi Nigorikawa
- Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Takehiko Sasaki
- Department of Biochemical Pathophysiology, Tokyo Medical and Dental University, Tokyo, 113-8510, Japan
| | - Koh Takeuchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Toshiya Senda
- Structural Biology Research Center, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki, 305-0801, Japan; Department of Accelerator Science, SOKENDAI, Japan; Faculty of Pure and Applied Sciences, University of Tsukuba, Ibaraki, 305-8572, Japan
| | - Seong M Kim
- Department of Developmental and Cell Biology, School of Biological Sciences, University of California Irvine, California, 92697, USA
| | - Aimee L Edinger
- Department of Developmental and Cell Biology, School of Biological Sciences, University of California Irvine, California, 92697, USA
| | - Anton Simeonov
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Atsuo T Sasaki
- Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA; Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, 997-0052, Japan; Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA; Department of Neurosurgery, Brain Tumor Center at UC Gardner Neuroscience Institute, Cincinnati, OH, 45267, USA; Department of Clinical and Molecular Genetics, Hiroshima University Hospital, Hiroshima, 734-8551, Japan.
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2
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Jung O, Baek MJ, Wooldrik C, Johnson KR, Fisher KW, Lou J, Ricks TJ, Wen T, Best MD, Cryns VL, Anderson RA, Choi S. Nuclear phosphoinositide signaling promotes YAP/TAZ-TEAD transcriptional activity in breast cancer. EMBO J 2024; 43:1740-1769. [PMID: 38565949 PMCID: PMC11066040 DOI: 10.1038/s44318-024-00085-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 02/29/2024] [Accepted: 03/08/2024] [Indexed: 04/04/2024] Open
Abstract
The Hippo pathway effectors Yes-associated protein 1 (YAP) and its homolog TAZ are transcriptional coactivators that control gene expression by binding to TEA domain (TEAD) family transcription factors. The YAP/TAZ-TEAD complex is a key regulator of cancer-specific transcriptional programs, which promote tumor progression in diverse types of cancer, including breast cancer. Despite intensive efforts, the YAP/TAZ-TEAD complex in cancer has remained largely undruggable due to an incomplete mechanistic understanding. Here, we report that nuclear phosphoinositides function as cofactors that mediate the binding of YAP/TAZ to TEADs. The enzymatic products of phosphoinositide kinases PIPKIα and IPMK, including phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and phosphatidylinositol 3,4,5-trisphosphate (P(I3,4,5)P3), bridge the binding of YAP/TAZ to TEAD. Inhibiting these kinases or the association of YAP/TAZ with PI(4,5)P2 and PI(3,4,5)P3 attenuates YAP/TAZ interaction with the TEADs, the expression of YAP/TAZ target genes, and breast cancer cell motility. Although we could not conclusively exclude the possibility that other enzymatic products of IPMK such as inositol phosphates play a role in the mechanism, our results point to a previously unrecognized role of nuclear phosphoinositide signaling in control of YAP/TAZ activity and implicate this pathway as a potential therapeutic target in YAP/TAZ-driven breast cancer.
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Affiliation(s)
- Oisun Jung
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA
| | - Min-Jeong Baek
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA
- Interdisciplinary Graduate Program in Biomedical Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - Colin Wooldrik
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA
- Interdisciplinary Graduate Program in Biomedical Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - Keith R Johnson
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA
- Department of Oral Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Kurt W Fisher
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Jinchao Lou
- Department of Chemistry, University of Tennessee, 1420 Circle Drive, Knoxville, TN, 37996, USA
| | - Tanei J Ricks
- Department of Chemistry, University of Memphis, 3744 Walker Avenue, Memphis, TN, 38152, USA
| | - Tianmu Wen
- University of Wisconsin Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Michael D Best
- Department of Chemistry, University of Tennessee, 1420 Circle Drive, Knoxville, TN, 37996, USA
| | - Vincent L Cryns
- University of Wisconsin Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Richard A Anderson
- University of Wisconsin Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Suyong Choi
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA.
- Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA.
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3
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Overduin M, Bhat R. Recognition and remodeling of endosomal zones by sorting nexins. Biochim Biophys Acta Biomembr 2024; 1866:184305. [PMID: 38408696 DOI: 10.1016/j.bbamem.2024.184305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 02/05/2024] [Accepted: 02/18/2024] [Indexed: 02/28/2024]
Abstract
The proteolipid code determines how cytosolic proteins find and remodel membrane surfaces. Here, we investigate how this process works with sorting nexins Snx1 and Snx3. Both proteins form sorting machines by recognizing membrane zones enriched in phosphatidylinositol 3-phosphate (PI3P), phosphatidylserine (PS) and cholesterol. This co-localized combination forms a unique "lipid codon" or lipidon that we propose is responsible for endosomal targeting, as revealed by structures and interactions of their PX domain-based readers. We outline a membrane recognition and remodeling mechanism for Snx1 and Snx3 involving this code element alongside transmembrane pH gradients, dipole moment-guided docking and specific protein-protein interactions. This generates an initial membrane-protein assembly (memtein) that then recruits retromer and additional PX proteins to recruit cell surface receptors for sorting to the trans-Golgi network (TGN), lysosome and plasma membranes. Post-translational modification (PTM) networks appear to regulate how the sorting machines form and operate at each level. The commonalities and differences between these sorting nexins show how the proteolipid code orchestrates parallel flows of molecular information from ribosome emergence to organelle genesis, and illuminates a universally applicable model of the membrane.
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Affiliation(s)
- Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.
| | - Rakesh Bhat
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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4
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Kervin TA, Overduin M. Membranes are functionalized by a proteolipid code. BMC Biol 2024; 22:46. [PMID: 38414038 PMCID: PMC10898092 DOI: 10.1186/s12915-024-01849-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 02/16/2024] [Indexed: 02/29/2024] Open
Abstract
Membranes are protein and lipid structures that surround cells and other biological compartments. We present a conceptual model wherein all membranes are organized into structural and functional zones. The assembly of zones such as receptor clusters, protein-coated pits, lamellipodia, cell junctions, and membrane fusion sites is explained to occur through a protein-lipid code. This challenges the theory that lipids sort proteins after forming stable membrane subregions independently of proteins.
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Affiliation(s)
- Troy A Kervin
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK.
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada.
| | - Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada.
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5
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Lourdes SR, Gurung R, Giri S, Mitchell CA, McGrath MJ. A new role for phosphoinositides in regulating mitochondrial dynamics. Adv Biol Regul 2024; 91:101001. [PMID: 38057188 DOI: 10.1016/j.jbior.2023.101001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 11/27/2023] [Indexed: 12/08/2023]
Abstract
Phosphoinositides are a minor group of membrane-associated phospholipids that are transiently generated on the cytoplasmic leaflet of many organelle membranes and the plasma membrane. There are seven functionally distinct phosphoinositides, each derived via the reversible phosphorylation of phosphatidylinositol in various combinations on the inositol ring. Their generation and termination is tightly regulated by phosphatidylinositol-kinases and -phosphatases. These enzymes can function together in an integrated and coordinated manner, whereby the phosphoinositide product of one enzyme may subsequently serve as a substrate for another to generate a different phosphoinositide species. This regulatory mechanism not only enables the transient generation of phosphoinositides on membranes, but also more complex sequential or bidirectional conversion pathways, and phosphoinositides can also be transferred between organelles via membrane contacts. It is this capacity to fine-tune phosphoinositide signals that makes them ideal regulators of membrane organization and dynamics, through their recruitment of signalling, membrane altering and lipid transfer proteins. Research spanning several decades has provided extensive evidence that phosphoinositides are major gatekeepers of membrane organization, with roles in endocytosis, exocytosis, autophagy, lysosome dynamics, vesicular transport and secretion, cilia, inter-organelle membrane contact, endosome maturation and nuclear function. By contrast, there has been remarkably little known about the role of phosphoinositides at mitochondria - an enigmatic and major knowledge gap, with challenges in reliably detecting phosphoinositides at this site. Here we review recent significant breakthroughs in understanding the role of phosphoinositides in regulating mitochondrial dynamics and metabolic function.
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Affiliation(s)
- Sonia Raveena Lourdes
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Rajendra Gurung
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Saveen Giri
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Christina A Mitchell
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
| | - Meagan J McGrath
- Cancer Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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6
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Wang T, Li X, Liu N, Yang Y, Gong Q. TurboID-based proximity labelling reveals a connection between VPS34 and cellular homeostasis. J Plant Physiol 2023; 289:154100. [PMID: 37748420 DOI: 10.1016/j.jplph.2023.154100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/19/2023] [Accepted: 09/19/2023] [Indexed: 09/27/2023]
Abstract
Unlike animals, plants and yeasts only have a class III phosphatidylinositol 3-kinase (PI3KC3). Its lipid product, phosphatidylinositol 3-phosphate (PtdIns-3-P, PI3P), organizes intracellular trafficking routes such as autophagosome formation, multivesicular body (MVB) formation, retro-transport from trans-Golgi network (TGN) to late Golgi, and the fusion events between autophagosomes and MVBs and the vacuole. The catalytic subunit of plant PI3KC3 is encoded by the essential gene Vacuolar Protein Sorting 34 (VPS34). Despite the importance of VPS34 in cellular homeostasis and plant development, a VPS34 interactome is lacking. Here we employed TurboID, an enzyme-catalyzed proximity labelling (PL) method, to describe a proximal interactome of Arabidopsis VPS34. TurboID catalyzed spatially restricted biotinylation and enabled VPS34-specific enrichment of 273 proteins from affinity purification coupled with mass spectrometry. The interactome confirmed known functions of VPS34 in endo-lysosomal trafficking. Intriguingly, carbohydrate metabolism was the most enriched Gene Ontology (GO) term, including glycolytic enzymes in the triose portion and enzymes functioning in chloroplast triose export and sucrose biosynthesis. The interaction between VPS34 and the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH, GAPC1/2) was validated in planta. Also verified was the interaction between VPS34 and the plasma membrane H+-ATPase AHA2, a primary determinant of membrane potential. Our study links PI3KC3 to carbohydrate metabolism and membrane potential, two key processes that maintain cellular homeostasis.
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Affiliation(s)
- Taotao Wang
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Xinjing Li
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Ningjing Liu
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Yi Yang
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Qingqiu Gong
- State Key Laboratory of Microbial Metabolism & Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
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7
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Wills RC, Doyle CP, Zewe JP, Pacheco J, Hansen SD, Hammond GRV. A novel homeostatic mechanism tunes PI(4,5)P2-dependent signaling at the plasma membrane. J Cell Sci 2023; 136:jcs261494. [PMID: 37534432 PMCID: PMC10482388 DOI: 10.1242/jcs.261494] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 07/19/2023] [Indexed: 08/04/2023] Open
Abstract
The lipid molecule phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] controls all aspects of plasma membrane (PM) function in animal cells, from its selective permeability to the attachment of the cytoskeleton. Although disruption of PI(4,5)P2 is associated with a wide range of diseases, it remains unclear how cells sense and maintain PI(4,5)P2 levels to support various cell functions. Here, we show that the PIP4K family of enzymes, which synthesize PI(4,5)P2 via a minor pathway, also function as sensors of tonic PI(4,5)P2 levels. PIP4Ks are recruited to the PM by elevated PI(4,5)P2 levels, where they inhibit the major PI(4,5)P2-synthesizing PIP5Ks. Perturbation of this simple homeostatic mechanism reveals differential sensitivity of PI(4,5)P2-dependent signaling to elevated PI(4,5)P2 levels. These findings reveal that a subset of PI(4,5)P2-driven functions might drive disease associated with disrupted PI(4,5)P2 homeostasis.
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Affiliation(s)
- Rachel C. Wills
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Colleen P. Doyle
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - James P. Zewe
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Jonathan Pacheco
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Scott D. Hansen
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
| | - Gerald R. V. Hammond
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
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8
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Bayona-Hernandez A, Guerra S, Jiménez-Ramirez IA, Sztacho M, Hozak P, Rodriguez-Zapata LC, Pereira-Santana A, Castaño E. LIPRNAseq: a method to discover lipid interacting RNAs by sequencing. Mol Biol Rep 2023; 50:6619-6626. [PMID: 37349607 DOI: 10.1007/s11033-023-08548-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 05/24/2023] [Indexed: 06/24/2023]
Abstract
BACKGROUND Current biological research extensively describes the interactions of molecules such as RNA with other nucleic acids or proteins. However, the relatively recent discovery of nuclear phospholipids playing biologically relevant processes outside membranes, as well as, RNA-lipid interactions shows the need for new methods to explore the identity of these RNAs. METHODS AND RESULTS In this study, we describe the method for LIPID-RNA isolation followed by sequencing and analysis of the RNA that has the ability to interact with the selected lipids. Here we utilized specific phospholipid coated beads for selective RNA binding. We tested RNA from organisms belonging to different realms (human, plant, and yeast), and tested their ability to bind a specific lipid. CONCLUSIONS The results show several RNAs differentially enriched in the pull-down of phosphatidyl Inositol 4,5 bisphosphate coated beads. This method is helpful to screen lipid-binding RNA, which may have relevant biological functions. The method can be used with different lipids and comparison of pull-downs and can narrow the selection of RNAs that interact with a particular lipid for further studies.
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Affiliation(s)
- Andrea Bayona-Hernandez
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Calle 43, Número 130, Chuburná de Hidalgo, Mérida, Yucatán, CP 97205, México
| | - Susana Guerra
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Calle 43, Número 130, Chuburná de Hidalgo, Mérida, Yucatán, CP 97205, México
| | - Irma Angélica Jiménez-Ramirez
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Calle 43, Número 130, Chuburná de Hidalgo, Mérida, Yucatán, CP 97205, México
| | - Martin Sztacho
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská, Prague, 1083, 142 20, Czech Republic
| | - Pavel Hozak
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská, Prague, 1083, 142 20, Czech Republic
| | - Luis Carlos Rodriguez-Zapata
- Unidad de Biotecnologia, Centro de Investigación Científica de Yucatán, Chuburná de Hidalgo, Calle 43, Número 130, Mérida, Yucatán, CP 97205, México
| | - Alejandro Pereira-Santana
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco A.C. Subsede Sureste, Parque Científico Tecnológico de Yucatán, Km 5.5 Carretera Sierra Papacal-Chuburná-Puerto, Mérida, 97302, Yucatán, México
- Dirección de Cátedras, Consejo Nacional de Ciencia y Tecnología, Ciudad de México, 03940, México
| | - Enrique Castaño
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Calle 43, Número 130, Chuburná de Hidalgo, Mérida, Yucatán, CP 97205, México.
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9
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Salita T, Rustam YH, Hofferek V, Jackson M, Tollestrup I, Sheridan JP, Schramm VL, Evans GB, Reid GE, Munkacsi AB. Phosphoinositide and redox dysregulation by the anticancer methylthioadenosine phosphorylase transition state inhibitor. Biochim Biophys Acta Mol Cell Biol Lipids 2023:159346. [PMID: 37301365 DOI: 10.1016/j.bbalip.2023.159346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 05/05/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023]
Abstract
Methylthio-DADMe-immucillin-A (MTDIA) is an 86 picomolar inhibitor of 5'-methylthioadenosine phosphorylase (MTAP) with potent and specific anti-cancer efficacy. MTAP salvages S-adenosylmethionine (SAM) from 5'-methylthioadenosine (MTA), a toxic metabolite produced during polyamine biosynthesis. Changes in MTAP expression are implicated in cancer growth and development, making MTAP an appealing target for anti-cancer therapeutics. Since SAM is involved in lipid metabolism, we hypothesised that MTDIA alters the lipidomes of MTDIA-treated cells. To identify these effects, we analysed the lipid profiles of MTDIA-treated Saccharomyces cerevisiae using ultra-high resolution accurate mass spectrometry (UHRAMS). MTAP inhibition by MTDIA, and knockout of the Meu1 gene that encodes for MTAP in yeast, caused global lipidomic changes and differential abundance of lipids involved in cell signaling. The phosphoinositide kinase/phosphatase signaling network was specifically impaired upon MTDIA treatment, and was independently validated and further characterised via altered localization of proteins integral to this network. Functional consequences of dysregulated lipid metabolism included a decrease in reactive oxygen species (ROS) levels induced by MTDIA that was contemporaneous with changes in immunological response factors (nitric oxide, tumour necrosis factor-alpha and interleukin-10) in mammalian cells. These results indicate that lipid homeostasis alterations and concomitant downstream effects may be associated with MTDIA mechanistic efficacy.
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Affiliation(s)
- Timothy Salita
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand; Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, Australia
| | - Yepy H Rustam
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, Australia
| | - Vinzenz Hofferek
- School of Chemistry, University of Melbourne, Parkville, Australia
| | - Michael Jackson
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Isaac Tollestrup
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Jeffrey P Sheridan
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Vern L Schramm
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Gary B Evans
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand
| | - Gavin E Reid
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, Australia; School of Chemistry, University of Melbourne, Parkville, Australia; Bio21 Molecular Science & Biotechnology Institute, University of Melbourne, Parkville, Australia
| | - Andrew B Munkacsi
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand.
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10
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Akefe IO, Osborne SL, Matthews B, Wallis TP, Meunier FA. Lipids and Secretory Vesicle Exocytosis. Adv Neurobiol 2023; 33:357-397. [PMID: 37615874 DOI: 10.1007/978-3-031-34229-5_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
In recent years, the number of studies implicating lipids in the regulation of synaptic vesicle exocytosis has risen considerably. It has become increasingly clear that lipids such as phosphoinositides, lysophospholipids, cholesterol, arachidonic acid and myristic acid play critical regulatory roles in the processes leading up to exocytosis. Lipids may affect membrane fusion reactions by altering the physical properties of the membrane, recruiting key regulatory proteins, concentrating proteins into exocytic "hotspots" or by modulating protein functions allosterically. Discrete changes in phosphoinositides concentration are involved in multiple trafficking events including exocytosis and endocytosis. Lipid-modifying enzymes such as the DDHD2 isoform of phospholipase A1 were recently shown to contribute to memory acquisition via dynamic modifications of the brain lipid landscape. Considering the increasing reports on neurodegenerative disorders associated with aberrant intracellular trafficking, an improved understanding of the control of lipid pathways is physiologically and clinically significant and will afford unique insights into mechanisms and therapeutic methods for neurodegenerative diseases. Consequently, this chapter will discuss the different classes of lipids, phospholipase enzymes, the evidence linking them to synaptic neurotransmitter release and how they act to regulate key steps in the multi-step process leading to neuronal communication and memory acquisition.
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Affiliation(s)
- Isaac O Akefe
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Shona L Osborne
- ARC Training Centre for Innovation in Biomedical Imaging Technology (CIBIT), The University of Queensland, St Lucia, QLD, Australia
| | - Benjamin Matthews
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia.
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia.
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11
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Abstract
Ca2+/voltage-gated, large conductance K+ channels (BKCa) are formed by homotetrameric association of α (slo1) subunits. Their activity, however, is suited to tissue-specific physiology largely due to their association with regulatory subunits (β and γ types), chaperone proteins, localized signaling, and the channel's lipid microenvironment. PIP2 and cholesterol can modulate BKCa activity independently of downstream signaling, yet activating Ca2+i levels and regulatory subunits control ligand action. At physiological Ca2+i and voltages, cholesterol and PIP2 reduce and increase slo1 channel activity, respectively. Moreover, slo1 proteins provide sites that seem to recognize cholesterol and PIP2: seven CRAC motifs in the slo1 cytosolic tail and a string of positively charged residues (Arg329, Lys330, Lys331) immediately after S6, respectively. A model that could explain the modulation of BKCa activity by cholesterol and/or PIP2 is hypothesized. The roles of additional sites, whether in slo1 or BKCa regulatory subunits, for PIP2 and/or cholesterol to modulate BKCa function are also discussed.
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Affiliation(s)
- Thirumalini Vaithianathan
- Department Pharmacology, Addiction Science, and Toxicology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Elizabeth H Schneider
- Department Pharmacology, Addiction Science, and Toxicology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Anna N Bukiya
- Department Pharmacology, Addiction Science, and Toxicology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Alex M Dopico
- Department Pharmacology, Addiction Science, and Toxicology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA.
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12
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Sailer SA, Burkhalter MD, Philipp M. Cholesterol and Phosphoinositides in Cilia Biology. Adv Exp Med Biol 2023; 1422:121-142. [PMID: 36988879 DOI: 10.1007/978-3-031-21547-6_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Cilia are evolutionarily conserved organelles that can be found on virtually every cell. They appear as hair-like structures emanating from the cellular surface either as single or as bundles of cilia. There, they sense external stimuli and translate them into intracellular signals. Motile cilia beat for the generation of locomotion of unicellular organisms or fluid flow in certain body cavities of vertebrate organisms. Defects in cilia are detrimental and account for the development of ciliopathies, one of the fastest-growing family of afflictions. In the past decade, membrane lipids, such as cholesterol and phosphoinositides, have emerged as essential elements in both the signal transduction via cilia and the building of cilia itself. Here, we summarize the current knowledge on the impact of cholesterol and phosphoinositides on cilium biology.
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Affiliation(s)
- Steffen-Alexander Sailer
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Division of Pharmacogenomics, University Hospital Tübingen, Tübingen, Germany
| | - Martin D Burkhalter
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Division of Pharmacogenomics, University Hospital Tübingen, Tübingen, Germany
| | - Melanie Philipp
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Division of Pharmacogenomics, University Hospital Tübingen, Tübingen, Germany.
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13
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Chu YN, Akahori A, Takatori S, Tomita T. Pathological Roles of INPP5D in Alzheimer's Disease. Adv Exp Med Biol 2023; 1423:289-301. [PMID: 37525057 DOI: 10.1007/978-3-031-31978-5_30] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Current hypothesis of Alzheimer's disease (AD) postulates that amyloid β (Aβ) deposition in the brain causes tau inclusion in neurons and leads to cognitive decline. The discovery of the genetic association between triggering receptor expressed on myeloid cells 2 (TREM2) with increased AD risk points to a causal link between microglia and AD pathogenesis, and revealed a crucial role of TREM2-dependent clustering of microglia around amyloid plaques that prevents Aβ toxicity to facilitate tau deposition near the plaques. Here we review the physiological and pathological roles of another AD risk gene expressed in microglia, inositol polyphosphate-5-polyphosphatase D (INPP5D), which encodes a phosphoinositide phosphatase. Evidence suggests that its risk polymorphisms alter the expression level and/or function of INPP5D, while concomitantly affecting tau levels in cerebrospinal fluids. In β-amyloidosis mice, INPP5D was upregulated upon Aβ deposition and negatively regulated the microglial clustering toward amyloid plaques. INPP5D seems to exert its function by acting antagonistically at downstream of the TREM2 signaling pathway, suggesting that it is a novel regulator of the protective barrier by microglia. Further studies to elucidate INPP5D's role in AD may help in developing new therapeutic targets for AD treatment.
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Affiliation(s)
- Yung Ning Chu
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Aika Akahori
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Sho Takatori
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Taisuke Tomita
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.
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14
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Li X, Shim S, Hardin KR, Vanaja KG, Song H, Levchenko A, Ming GL, Zheng JQ. Signal amplification in growth cone gradient sensing by a double negative feedback loop among PTEN, PI(3,4,5)P 3 and actomyosin. Mol Cell Neurosci 2022; 123:103772. [PMID: 36055521 PMCID: PMC9856701 DOI: 10.1016/j.mcn.2022.103772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/23/2022] [Accepted: 08/26/2022] [Indexed: 01/24/2023] Open
Abstract
Axon guidance during neural wiring involves a series of precisely controlled chemotactic events by the motile axonal tip, the growth cone. A fundamental question is how neuronal growth cones make directional decisions in response to extremely shallow gradients of guidance cues with exquisite sensitivity. Here we report that nerve growth cones possess a signal amplification mechanism during gradient sensing process. In neuronal growth cones of Xenopus spinal neurons, phosphatidylinositol-3,4,5-trisphosphate (PIP3), an important signaling molecule in chemotaxis, was actively recruited to the up-gradient side in response to an external gradient of brain-derived neurotrophic factor (BDNF), resulting in an intracellular gradient with approximate 30-fold amplification of the input. Furthermore, a reverse gradient of phosphatase and tensin homolog (PTEN) was induced by BDNF within the growth cone and the increased PTEN activity at the down-gradient side is required for the amplification of PIP3 signals. Mechanistically, the establishment of both positive PIP3 and reverse PTEN gradients depends on the filamentous actin network. Together with computational modeling, our results revealed a double negative feedback loop among PTEN, PIP3 and actomyosin for signal amplification, which is essential for gradient sensing of neuronal growth cones in response to diffusible cues.
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Affiliation(s)
- Xiong Li
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Sangwoo Shim
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; Department of Cell Biology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA 30322, USA
| | - Katherine R Hardin
- Department of Cell Biology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA 30322, USA
| | - Kiran G Vanaja
- Department of Biomedical Engineering and Yale Systems Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Hongjun Song
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA
| | - Andre Levchenko
- Department of Biomedical Engineering and Yale Systems Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Guo-Li Ming
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA
| | - James Q Zheng
- Department of Cell Biology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA 30322, USA.
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15
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Nugues C, Rajamanoharan D, Burgoyne RD, Haynes LP, Helassa N. Lysosome exocytosis is required for mitosis in mammalian cells. Biochem Biophys Res Commun 2022; 626:211-9. [PMID: 35998546 DOI: 10.1016/j.bbrc.2022.08.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 08/09/2022] [Indexed: 11/20/2022]
Abstract
Mitosis, the accurate segregation of duplicated genetic material into what will become two new daughter cells, is accompanied by extensive membrane remodelling and membrane trafficking activities. Early in mitosis, adherent cells partially detach from the substratum, round up and their surface area decreases. This likely results from an endocytic uptake of plasma membrane material. As cells enter cytokinesis they re-adhere, flatten and exhibit an associated increase in surface area. The identity of the membrane donor for this phase of mitosis remains unclear. In this paper we demonstrate how lysosomes dynamically redistribute during mitosis and exocytose. Antagonism of lysosomal exocytosis by pharmacological and genetic approaches causes mitosis failure in a significant proportion of cells. We speculate that either lysosomal membrane or luminal content release, possibly both, are therefore required for normal mitosis progression. These findings are important as they reveal a new process required for successful cell division.
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16
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Ellena JF, Tang TX, Shanaiah N, Capelluto DGS. Backbone 1H, 15N, and 13C resonance assignments of the Phafin2 pleckstrin homology domain. Biomol NMR Assign 2022; 16:27-30. [PMID: 34739631 PMCID: PMC9068824 DOI: 10.1007/s12104-021-10054-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 10/27/2021] [Indexed: 05/27/2023]
Abstract
Phafin2 is a peripheral protein that triggers cellular signaling from endosomal and lysosomal compartments. The specific subcellular localization of Phafin2 is mediated by the presence of a tandem of phosphatidylinositol 3-phosphate (PtdIns3P)-binding domains, the pleckstrin homology (PH) and the Fab-1, YOTB, Vac1, and EEA1 (FYVE) domains. The requirement for both domains for binding to PtdIns3P still remains unclear. To understand the molecular interactions of the Phafin2 PH domain in detail, we report its nearly complete 1H, 15N, and 13C backbone resonance assignments.
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Affiliation(s)
- Jeffrey F Ellena
- Biomolecular Magnetic Resonance Facility, University of Virginia, Charlottesville, VA, 22904, USA
| | - Tuo-Xian Tang
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA
- Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | | | - Daniel G S Capelluto
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, 24061, USA.
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17
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de la Cruz L, Riquelme R, Vivas O, Barria A, Jensen JB. Dishevelled coordinates phosphoinositide kinases PI4KIIIα and PIP5KIγ for efficient PtdInsP2 synthesis. J Cell Sci 2022; 135:274231. [PMID: 34982154 PMCID: PMC8919331 DOI: 10.1242/jcs.259145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 12/14/2021] [Indexed: 02/05/2023] Open
Abstract
Phosphatidylinositol(4,5)-bisphosphate (PtdInsP2) is an important modulator of many cellular processes, and its abundance in the plasma membrane is closely regulated. We examined the hypothesis that members of the Dishevelled scaffolding protein family can bind the lipid kinases phosphatidylinositol 4-kinase (PI4K) and phosphatidylinositol 4-phosphate 5-kinase (PIP5K), facilitating synthesis of PtdInsP2 directly from phosphatidylinositol. We used several assays for PtdInsP2 to examine the cooperative function of phosphoinositide kinases and the Dishevelled protein Dvl3 in the context of two receptor signaling cascades. Simultaneous overexpression of PI4KIIIα (also known as PI4KA) and PIP5KIγ (also known as PIP5K1C) had a synergistic effect on PtdInsP2 synthesis that was recapitulated by overexpression of Dvl3. Increasing the activity of Dvl3 by overexpression increased resting plasma membrane PtdInsP2. Knockdown of Dvl3 reduced resting plasma membrane PtdInsP2 and slowed PtdInsP2 resynthesis following receptor activation. We confirm that Dvl3 promotes coupling of PI4KIIIα and PIP5KIγ and show that this interaction is essential for efficient resynthesis of PtdInsP2 following receptor activation.
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18
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Shimizu T, Yanase N, Fujii T, Sakakibara H, Sakai H. Regulation of TRPV1 channel activities by intracellular ATP in the absence of capsaicin. Biochim Biophys Acta Biomembr 2022; 1864:183782. [PMID: 34555418 DOI: 10.1016/j.bbamem.2021.183782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 09/10/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Transient receptor potential vanilloid 1 (TRPV1) is a voltage-dependent non-selective cation channel activated by capsaicin, the main pungent ingredient of chili peppers, and noxious heat. Although TRPV1 channels produce outwardly rectifying currents even in the absence of capsaicin, little is known about the regulation mechanism of the TRPV1 currents. In the present study, we found that intracellular ATP regulates the basal activities of TRPV1 channels in a concentration-dependent manner. The ATP-dependent regulation of TRPV1 channels was mediated by phosphoinositides. Moreover, an increase in intracellular ATP concentration negatively shifted voltage-dependent activation of TRPV1 channels. These results suggest that the ATP-dependent production of phosphoinositides regulates the voltage-dependent gating of the basal TRPV1 channel activities in the absence of capsaicin.
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Affiliation(s)
- Takahiro Shimizu
- Department of Pharmaceutical Physiology, Faculty of Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan.
| | - Nobuhiro Yanase
- Department of Pharmaceutical Physiology, Faculty of Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
| | - Takuto Fujii
- Department of Pharmaceutical Physiology, Faculty of Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
| | - Haruka Sakakibara
- Department of Pharmaceutical Physiology, Faculty of Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
| | - Hideki Sakai
- Department of Pharmaceutical Physiology, Faculty of Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
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19
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Olkkonen VM, Ikonen E. Cholesterol transport in the late endocytic pathway: Roles of ORP family proteins. J Steroid Biochem Mol Biol 2022; 216:106040. [PMID: 34864207 DOI: 10.1016/j.jsbmb.2021.106040] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/24/2021] [Accepted: 12/01/2021] [Indexed: 12/29/2022]
Abstract
Oxysterol-binding protein (OSBP) homologues, designated ORP or OSBPL proteins, constitute one of the largest families of intracellular lipid-binding/transfer proteins (LTP). This review summarizes the mounting evidence that several members of this family participate in the machinery facilitating cholesterol trafficking in the late endocytic pathway. There are indications that OSBP, besides acting as a cholesterol/phosphatidylinositol 4-phosphate (PI4P) exchanger at the endoplasmic reticulum (ER)-trans-Golgi network (TGN) membrane contact sites (MCS), also exchanges these lipids at ER-lysosome (Lys) contacts, increasing Lys cholesterol content. The long isoform of ORP1 (ORP1L), which also targets ER-late endosome (LE)/Lys MCS, has the capacity to mediate cholesterol transport either from ER to LE or in the opposite direction. Moreover, it regulates the motility, positioning and fusion of LE as well as autophagic flux. ORP2, the closest relative of ORP1, is mainly cytosolic, but also targets PI(4,5)P2-rich endosomal compartments. Our latest data suggest that ORP2 transfers cholesterol from LE to recycling endosomes (RE) in exchange for PI(4,5)P2, thus stimulating the recruitment of focal adhesion kinase (FAK) on the RE and cell adhesion. FAK activates phosphoinositide kinase on the RE to enhance PI(4,5)P2 synthesis. ORP2 in turn transfers PI(4,5)P2 from RE to LE, thus regulating LE tubule formation and transport activity.
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Affiliation(s)
- Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Anatomy, Faculty of Medicine, University of Helsinki, Finland.
| | - Elina Ikonen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Anatomy, Faculty of Medicine, University of Helsinki, Finland; Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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20
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Kim JH, Jung H, Choi YE, Chung T. Autophagy inducers lead to transient accumulation of autophagosomes in Arabidopsis roots. Plant Cell Rep 2022; 41:463-471. [PMID: 34977975 DOI: 10.1007/s00299-021-02821-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/22/2021] [Indexed: 06/14/2023]
Abstract
This study reveals that plant roots show a rapid termination of autophagy induction, offering a plant model for studying how excessive autophagy is deterred. In eukaryotes, autophagy is an intracellular mechanism that is important for recycling nutrients by degrading various macromolecules and organelles in vacuoles and lysosomes. Autophagy is induced when the nutrient supply to plant cells is limited. The protein kinase target of rapamycin (TOR) complex negatively regulates autophagy when nutrients are present in adequate amounts. The TOR inhibitor AZD8055 is an autophagy inducer that is useful for studying starvation-induced autophagy in plant cells. The mechanism by which AZD8055 increases the autophagic flux in plant cells has not been studied in detail. Here, we show that AZD8055-induced autophagy requires phosphatidylinositol 3-kinase activity and canonical AUTOPHAGY-RELATED (ATG) genes in Arabidopsis thaliana. Autophagic flux rapidly increased in seedlings treated with AZD8055. Unexpectedly, autophagy induction was transient in root cells and terminated earlier than in cotyledon cells. Transient induction is partly caused by a temporary effect of AZD8055 on phagophore initiation. These findings indicate a TOR-independent mechanism for terminating autophagy induction, thereby paving the way for elucidating how excess autophagy is prevented in plant roots.
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Affiliation(s)
- Jeong Hun Kim
- Department of Biological Sciences, Pusan National University, 63 Beon-gil 2, Busandaehag-ro, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Hyera Jung
- Department of Biological Sciences, Pusan National University, 63 Beon-gil 2, Busandaehag-ro, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Ye Eun Choi
- Department of Biological Sciences, Pusan National University, 63 Beon-gil 2, Busandaehag-ro, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Taijoon Chung
- Department of Biological Sciences, Pusan National University, 63 Beon-gil 2, Busandaehag-ro, Geumjeong-gu, Busan, 46241, Republic of Korea.
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21
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Ware TB, Hsu KL. Advances in chemical proteomic evaluation of lipid kinases-DAG kinases as a case study. Curr Opin Chem Biol 2021; 65:101-108. [PMID: 34311404 PMCID: PMC8671151 DOI: 10.1016/j.cbpa.2021.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/24/2021] [Accepted: 06/18/2021] [Indexed: 10/20/2022]
Abstract
Advancements in chemical proteomics and mass spectrometry lipidomics are providing new opportunities to understand lipid kinase activity, specificity, and regulation on a global cellular scale. Here, we describe recent developments in chemical biology of lipid kinases with a focus on those members that phosphorylate diacylglycerols. We further discuss future implications of how these mass spectrometry-based approaches can be adapted for studies of additional lipid kinase members with the aim of bridging the gap between protein and lipid kinase-focused investigations.
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Affiliation(s)
- Timothy B Ware
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, United States
| | - Ku-Lung Hsu
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, United States; Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, United States; Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908, United States; University of Virginia Cancer Center, University of Virginia, Charlottesville, VA 22903, USA.
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22
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Ikhlef S, Lipp NF, Delfosse V, Fuggetta N, Bourguet W, Magdeleine M, Drin G. Functional analyses of phosphatidylserine/PI(4)P exchangers with diverse lipid species and membrane contexts reveal unanticipated rules on lipid transfer. BMC Biol 2021; 19:248. [PMID: 34801011 PMCID: PMC8606082 DOI: 10.1186/s12915-021-01183-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/04/2021] [Indexed: 11/14/2022] Open
Abstract
Background Lipid species are accurately distributed in the eukaryotic cell so that organelle and plasma membranes have an adequate lipid composition to support numerous cellular functions. In the plasma membrane, a precise regulation of the level of lipids such as phosphatidylserine, PI(4)P, and PI(4,5)P2, is critical for maintaining the signaling competence of the cell. Several lipid transfer proteins of the ORP/Osh family contribute to this fine-tuning by delivering PS, synthesized in the endoplasmic reticulum, to the plasma membrane in exchange for PI(4)P. To get insights into the role of these PS/PI(4)P exchangers in regulating plasma membrane features, we question how they selectively recognize and transfer lipid ligands with different acyl chains, whether these proteins exchange PS exclusively for PI(4)P or additionally for PI(4,5)P2, and how sterol abundance in the plasma membrane impacts their activity. Results We measured in vitro how the yeast Osh6p and human ORP8 transported PS and PI(4)P subspecies of diverse length and unsaturation degree between membranes by fluorescence-based assays. We established that the exchange activity of Osh6p and ORP8 strongly depends on whether these ligands are saturated or not, and is high with representative cellular PS and PI(4)P subspecies. Unexpectedly, we found that the speed at which these proteins individually transfer lipid ligands between membranes is inversely related to their affinity for them and that high-affinity ligands must be exchanged to be transferred more rapidly. Next we determined that Osh6p and ORP8 cannot use PI(4,5)P2 for exchange processes, because it is a low-affinity ligand, and do not transfer more PS into sterol-rich membranes. Conclusions Our study provides new insights into PS/PI(4)P exchangers by indicating the degree to which they can regulate the acyl chain composition of the PM, and how they control PM phosphoinositide levels. Moreover, we establish general rules on how the activity of lipid transfer proteins relates to their affinity for ligands. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01183-1.
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Affiliation(s)
- Souade Ikhlef
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France
| | - Nicolas-Frédéric Lipp
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France.,Current position: Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA
| | - Vanessa Delfosse
- Centre de Biologie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Nicolas Fuggetta
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France
| | - William Bourguet
- Centre de Biologie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Maud Magdeleine
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France
| | - Guillaume Drin
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France.
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Maxson ME, Sarantis H, Volchuk A, Brumell JH, Grinstein S. Rab5 regulates macropinocytosis by recruiting the inositol 5-phosphatases OCRL and Inpp5b that hydrolyse PtdIns(4,5)P2. J Cell Sci 2021; 134:237783. [PMID: 33722976 DOI: 10.1242/jcs.252411] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 02/25/2021] [Indexed: 01/09/2023] Open
Abstract
Rab5 is required for macropinosome formation, but its site and mode of action remain unknown. We report that Rab5 acts at the plasma membrane, downstream of ruffling, to promote macropinosome sealing and scission. Dominant-negative Rab5, which obliterates macropinocytosis, had no effect on the development of membrane ruffles. However, Rab5-containing vesicles were recruited to circular membrane ruffles, and soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-dependent endomembrane fusion was necessary for the completion of macropinocytosis. This fusion event coincided with the disappearance of PtdIns(4,5)P2 that accompanies macropinosome closure. Counteracting the depletion of PtdIns(4,5)P2 by expression of phosphatidylinositol-4-phosphate 5-kinase impaired macropinosome formation. Importantly, we found that the removal of PtdIns(4,5)P2 is dependent on Rab5, through the Rab5-mediated recruitment of the inositol 5-phosphatases OCRL and Inpp5b, via APPL1. Knockdown of OCRL and Inpp5b, or APPL1, prevented macropinosome closure without affecting ruffling. We therefore propose that Rab5 is essential for the clearance of PtdIns(4,5)P2 needed to complete the scission of macropinosomes or to prevent their back-fusion with the plasmalemma.
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Affiliation(s)
- Michelle E Maxson
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Helen Sarantis
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Allen Volchuk
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - John H Brumell
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada.,SickKids IBD Centre, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario M5S 1A1, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A1, Canada
| | - Sergio Grinstein
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada.,Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada
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24
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Abstract
Phosphoinositides (PIPs) are lipid messengers with different functions according to their localization. After their local production by the action of lipid kinases or phosphatases, PIPs regulate various biological processes such as cytoskeleton rearrangement, membrane remodeling/trafficking, or gene expression through binding of their phosphorylated inositol head group with different protein domains such as PH, PX, and FYVE. It is well known that PIPs regulate the activity of small GTPases by interacting with and activating Guanyl-nucleotide Exchange Factor (GEF) proteins through specific domains such as the ones mentioned above. However, most of the in vitro assays to assess the activation of GTPases focus on the GTPase only and neglect the fact that co-activators, such as membranes and protein activators, have a significant effect in vivo. Herein, we describe not only the classical protein-lipid overlay and liposome sedimentation methods but also an assay we have developed, which contains three partners: a liposome which composition reproduces the membrane of the target of the GTPase, the recombinant specific DH-(PIP affinity) GEF domain, and the recombinant GTPase to be tested by different PIPs. This assay allows us to clearly quantify the GTPase activation.
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25
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Effertz T, Moser T, Oliver D. Recent advances in cochlear hair cell nanophysiology: subcellular compartmentalization of electrical signaling in compact sensory cells. Fac Rev 2021; 9:24. [PMID: 33659956 PMCID: PMC7886071 DOI: 10.12703/r/9-24] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In recent years, genetics, physiology, and structural biology have advanced into the molecular details of the sensory physiology of auditory hair cells. Inner hair cells (IHCs) and outer hair cells (OHCs) mediate two key functions: active amplification and non-linear compression of cochlear vibrations by OHCs and sound encoding by IHCs at their afferent synapses with the spiral ganglion neurons. OHCs and IHCs share some molecular physiology, e.g. mechanotransduction at the apical hair bundles, ribbon-type presynaptic active zones, and ionic conductances in the basolateral membrane. Unique features enabling their specific function include prestin-based electromotility of OHCs and indefatigable transmitter release at the highest known rates by ribbon-type IHC active zones. Despite their compact morphology, the molecular machineries that either generate electrical signals or are driven by these signals are essentially all segregated into local subcellular structures. This review provides a brief account on recent insights into the molecular physiology of cochlear hair cells with a specific focus on organization into membrane domains.
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Affiliation(s)
- Thomas Effertz
- InnerEarLab, Department of Otorhinolaryngology, University Medical Center Göttingen, 37099 Göttingen, Germany
| | - Tobias Moser
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, 37099 Göttingen, Germany
- Auditory Neuroscience Group, Max Planck Institute for Experimental Medicine, 37075 Göttingen, Germany
- Synaptic Nanophysiology Group, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
- Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, 37075 Göttingen, Germany
| | - Dominik Oliver
- Institute for Physiology and Pathophysiology, Philipps University, Deutschhausstraße 2, 35037 Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), Universities of Marburg and Giessen, Germany
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodelling, GRK 2213, Philipps University, Marburg, Germany
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26
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Tsutsui H, Mizutani N, Okamura Y. Engineering voltage sensing phosphatase (VSP). Methods Enzymol 2021; 654:85-114. [PMID: 34120726 DOI: 10.1016/bs.mie.2021.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Voltage sensing phosphatase (VSP), consists of a voltage sensor domain (VSD) like that found in voltage-gated ion channels and a phosphoinositide (PIP) phosphatase region exhibiting remarkable structural similarity to a tumor suppressor enzyme, PTEN. Membrane depolarization activates the enzyme activity through tight coupling between the VSD and enzyme region. The VSD of VSP has a unique nature; it is a self-contained module that can be transferred to other proteins, conferring voltage sensitivity. Thanks to this nature, numerous versions of gene-encoded voltage indicators (GEVIs) have been developed through combination of a fluorescent protein with the VSD of VSP. In addition, VSP itself can also serve as a tool to alter PIP levels in cells. Cellular levels of PIPs, PI(4,5)P2 in particular, can be acutely and transiently reduced using a simple voltage protocol after heterologous expression of VSP. Recent progress in our understanding of the molecular structure and mechanisms underlying VSP facilitates optimization of its molecular properties for its use as a molecular tool.
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Affiliation(s)
- Hidekazu Tsutsui
- School of Materials Science, Japan Advanced Institute of Science and Technology (JAIST), Nomi, Ishikawa, Japan.
| | - Natsuki Mizutani
- Graduate School of Medicine, Japan Advanced Institute of Science and Technology (JAIST), Osaka University, Suita, Osaka, Japan
| | - Yasushi Okamura
- Graduate School of Medicine, Japan Advanced Institute of Science and Technology (JAIST), Osaka University, Suita, Osaka, Japan.
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27
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Ravussin A, Brech A, Tooze SA, Stenmark H. The phosphatidylinositol 3-phosphate-binding protein SNX4 controls ATG9A recycling and autophagy. J Cell Sci 2021; 134:jcs250670. [PMID: 33468622 PMCID: PMC7888711 DOI: 10.1242/jcs.250670] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 12/21/2020] [Indexed: 12/11/2022] Open
Abstract
Late endosomes and lysosomes (endolysosomes) receive proteins and cargo from the secretory, endocytic and autophagic pathways. Although these pathways and the degradative processes of endolysosomes are well characterized, less is understood about protein traffic from these organelles. In this study, we demonstrate the direct involvement of the phosphatidylinositol 3-phosphate (PI3P)-binding SNX4 protein in membrane protein recycling from endolysosomes, and show that SNX4 is required for proper autophagic flux. We show that SNX4 mediates recycling of the lipid scramblase ATG9A, which drives expansion of nascent autophagosome membranes, from endolysosomes to early endosomes, from where ATG9A is recycled to the trans-Golgi network in a retromer-dependent manner. Upon siRNA-mediated depletion of SNX4 or the retromer component VPS35, we observed accumulation of ATG9A on endolysosomes and early endosomes, respectively. Moreover, starvation-induced autophagosome biogenesis and autophagic flux were inhibited when SNX4 was downregulated. We propose that proper ATG9A recycling by SNX4 sustains autophagy by preventing exhaustion of the available ATG9A pool.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Anthony Ravussin
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, 0379 Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379 Oslo, Norway
| | - Andreas Brech
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, 0379 Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379 Oslo, Norway
| | - Sharon A Tooze
- Molecular Cell Biology of Autophagy Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Harald Stenmark
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, 0379 Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379 Oslo, Norway
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28
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Smallman MA, Filtz TM, Stormshak F. Mifepristone and PGF 2α activate phosphatidylinositol hydrolysis in the ovine corpus luteum. Prostaglandins Other Lipid Mediat 2021; 153:106538. [PMID: 33545368 DOI: 10.1016/j.prostaglandins.2021.106538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 01/18/2021] [Accepted: 01/26/2021] [Indexed: 10/22/2022]
Abstract
Two experiments were conducted to determine whether mifepristone (RU486) and PGF2α activate the phosphatidylinositol hydrolysis pathway during the midluteal phase of the ovine estrous cycle. In experiment 1, ewes on day 8 of the cycle were given 10 μg RU486 or vehicle into the ovarian artery with removal of the corpus luteum (CL) after 10 min. Blood collected prior to and after treatment was analyzed for progesterone. Aliquots of CL were incubated with 10 μCi of 3H-inositol and in the presence and absence of PGF2α (10 nM) for 15 min. Exposure of CL to RU486 and PGF2α increased phosphatidylinositol hydrolysis (p < 0.05). Serum progesterone was reduced in both control and RU486-treated ewes (p < 0.05) compared to concentrations before treatments. In experiment 2, aliquots of CL collected from ewes on day 8 of the cycle were incubated with 3H-inositol and exposed to RU486 (2 μM) in the presence and absence of PGF2α (1 μM) for 15 min. Treatments stimulated phosphatidylinositol hydrolysis as in Exp 1 (p < 0.05). Progesterone concentrations in incubation medium were increased in response to RU486 and PGF2α (p < 0.05). Collectively, these data suggest that RU486 and PGF2α act to stimulate phosphatidylinositol hydrolysis in the mature ovine CL.
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Affiliation(s)
- Mary A Smallman
- Oregon State University, Department of Animal and Rangeland Science, Corvallis, OR 97331, USA.
| | - Theresa M Filtz
- Oregon State University, College of Pharmacy, Corvallis, OR 97331, USA
| | - Fredrick Stormshak
- Oregon State University, Department of Animal and Rangeland Science, Corvallis, OR 97331, USA
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29
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Mansat M, Picot M, Chicanne G, Nahoum V, Gaits-Iacovoni F, Payrastre B, Hnia K, Viaud J. Liposome-Based Methods to Study Protein- Phosphoinositide Interaction. Methods Mol Biol 2021; 2251:177-184. [PMID: 33481239 DOI: 10.1007/978-1-0716-1142-5_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Following their generation by lipid kinases and phosphatases, phosphoinositides regulate important biological processes such as cytoskeleton rearrangement, membrane remodeling/trafficking, and gene expression through the interaction of their phosphorylated inositol head group with a variety of protein domains such as PH, PX, and FYVE. Therefore, it is important to determine the specificity of phosphoinositides toward effector proteins to understand their impact on cellular physiology. Several methods have been developed to identify and characterize phosphoinositide effectors, and liposomes-based methods are preferred because the phosphoinositides are incorporated in a membrane, the composition of which can mimic cellular membranes. In this report, we describe the experimental setup for liposome flotation assay and a recently developed method called protein-lipid interaction by fluorescence (PLIF) for the characterization of phosphoinositide-binding specificities of proteins.
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Affiliation(s)
- Mélanie Mansat
- INSERM U1048 and Université Toulouse 3, Toulouse Cedex, France
| | - Mélanie Picot
- INSERM U1048 and Université Toulouse 3, Toulouse Cedex, France
| | - Gaëtan Chicanne
- INSERM U1048 and Université Toulouse 3, Toulouse Cedex, France
| | - Virginie Nahoum
- CNRS, Institut de Pharmacologie et de Biologie Structurale (IPBS), Toulouse, France
- Université de Toulouse, UPS (Université Paul Sabatier), IPBS, Toulouse, France
| | | | - Bernard Payrastre
- INSERM U1048 and Université Toulouse 3, Toulouse Cedex, France
- CHU (Centre Hospitalier Universitaire) de Toulouse, Laboratoire d'Hématologie, Toulouse Cedex, France
| | - Karim Hnia
- INSERM U1048 and Université Toulouse 3, Toulouse Cedex, France
| | - Julien Viaud
- INSERM U1048 and Université Toulouse 3, Toulouse Cedex, France.
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30
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Schurmans S, Vande Catsyne CA, Desmet C, Moës B. The phosphoinositide 5-phosphatase INPP5K: From gene structure to in vivo functions. Adv Biol Regul 2021; 79:100760. [PMID: 33060052 DOI: 10.1016/j.jbior.2020.100760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
INPP5K (Inositol Polyphosphate 5-Phosphatase K, or SKIP (for Skeletal muscle and Kidney enriched Inositol Phosphatase) is a member of the phosphoinositide 5-phosphatases family. Its protein structure is comprised of a N-terminal catalytic domain which hydrolyses both PtdIns(4,5)P2 and PtdIns(3,4,5)P3, followed by a SKICH domain at the C-terminus which is responsible for protein-protein interactions and subcellular localization of INPP5K. Strikingly, INPP5K is mostly concentrated in the endoplasmic reticulum, although it is also detected at the plasma membrane, in the cytosol and the nucleus. Recently, mutations in INPP5K have been detected in patients with a rare form of autosomal recessive congenital muscular dystrophy with cataract, short stature and intellectual disability. INPP5K functions extend from control of insulin signaling, endoplasmic reticulum stress response and structural integrity, myoblast differentiation, cytoskeleton organization, cell adhesion and migration, renal osmoregulation, to cancer. The goal of this review is thus to summarize and comment recent and less recent data in the literature on INPP5K, in particular on the structure, expression, intracellular localization, interactions and functions of this specific member of the 5-phosphatases family.
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Affiliation(s)
- Stéphane Schurmans
- Laboratoire de Génétique Fonctionnelle, GIGA-Research Centre, Building B34, CHU Sart-Tilman, Université de Liège, Avenue de l'Hôpital 11, 4000-Liège, Belgium; Secteur de Biochimie Métabolique Vétérinaire, Département des Sciences Fonctionnelles, Faculté de Médecine Vétérinaire, Building B42, Université de Liège, Quartier Vallée 2, Avenue de Cureghem 7A-7D, 4000-Liège, Belgium.
| | - Charles-Andrew Vande Catsyne
- Laboratoire de Génétique Fonctionnelle, GIGA-Research Centre, Building B34, CHU Sart-Tilman, Université de Liège, Avenue de l'Hôpital 11, 4000-Liège, Belgium
| | - Christophe Desmet
- Laboratory of Cellular and Molecular Immunology, GIGA-Research Centre, Building B34, CHU Sart-Tilman, Université de Liège, Avenue de l'Hôpital 11, 4000-Liège, Belgium
| | - Bastien Moës
- Laboratoire de Génétique Fonctionnelle, GIGA-Research Centre, Building B34, CHU Sart-Tilman, Université de Liège, Avenue de l'Hôpital 11, 4000-Liège, Belgium
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31
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Edgar JR, Ho AK, Laurá M, Horvath R, Reilly MM, Luzio JP, Roberts RC. A dysfunctional endolysosomal pathway common to two sub-types of demyelinating Charcot-Marie-Tooth disease. Acta Neuropathol Commun 2020; 8:165. [PMID: 33059769 PMCID: PMC7559459 DOI: 10.1186/s40478-020-01043-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 09/24/2020] [Indexed: 12/17/2022] Open
Abstract
Autosomal dominant mutations in LITAF are responsible for the rare demyelinating peripheral neuropathy, Charcot-Marie-Tooth disease type 1C (CMT1C). The LITAF protein is expressed in many human cell types and we have investigated the consequences of two different LITAF mutations in primary fibroblasts from CMT1C patients using confocal and electron microscopy. We observed the appearance of vacuolation/enlargement of late endocytic compartments (late endosomes and lysosomes). This vacuolation was also observed after knocking out LITAF from either control human fibroblasts or from the CMT1C patient-derived cells, consistent with it being the result of loss-of-function mutations in the CMT1C fibroblasts. The vacuolation was similar to that previously observed in fibroblasts from CMT4J patients, which have autosomal recessive mutations in FIG4. The FIG4 protein is a component of a phosphoinositide kinase complex that synthesises phosphatidylinositol 3,5-bisphosphate on the limiting membrane of late endosomes. Phosphatidylinositol 3,5-bisphosphate activates the release of lysosomal Ca2+ through the cation channel TRPML1, which is required to maintain the homeostasis of endosomes and lysosomes in mammalian cells. We observed that a small molecule activator of TRPML1, ML-SA1, was able to rescue the vacuolation phenotype of LITAF knockout, FIG4 knockout and CMT1C patient fibroblasts. Our data describe the first cellular phenotype common to two different subtypes of demyelinating CMT and are consistent with LITAF and FIG4 functioning on a common endolysosomal pathway that is required to maintain the homeostasis of late endosomes and lysosomes. Although our experiments were on human fibroblasts, they have implications for our understanding of the molecular pathogenesis and approaches to therapy in two subtypes of demyelinating Charcot-Marie-Tooth disease.
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Affiliation(s)
- James R Edgar
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK.
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK.
| | - Anita K Ho
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
- Department of Biology, University of York, York, YO10 5DD, UK
| | - Matilde Laurá
- Centre for Neuromuscular Diseases, UCL, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Rita Horvath
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0PY, UK
| | - Mary M Reilly
- Centre for Neuromuscular Diseases, UCL, Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - J Paul Luzio
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Rhys C Roberts
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK.
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0PY, UK.
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32
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Lee HN, Jung H, Chung T. Subcellular Localization of PI3P in Arabidopsis. Methods Mol Biol 2020; 2177:109-18. [PMID: 32632809 DOI: 10.1007/978-1-0716-0767-1_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Phosphatidylinositol-3-phosphate (PI3P) is a signaling phospholipid enriched in the membranes of late endosomes (LE) and vacuoles. PI3P mediates vacuolar and endosomal trafficking through recruiting PI3P-binding effector proteins to the LE. PI3P is produced from phosphatidylinositol by the PI 3-kinase complex containing VACUOLAR PROTEIN SORTING 34 (VPS34). The role of PI3P has been elucidated by using genetically encoded PI3P biosensors. We previously showed that Arabidopsis VPS38, a component of the VPS34 complex, localized at the LE and that VPS38 is essential for proper PI3P distribution in endosomal and vacuolar trafficking routes. In this chapter, we describe methods for microscopic imaging of PI3P using the PI3P biosensor citrine-2 × FYVE and the PI 3-kinase inhibitors.
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Poli A, Fiume R, Mongiorgi S, Zaurito A, Sheth B, Vidalle MC, Hamid SA, Kimber S, Campagnoli F, Ratti S, Rusciano I, Faenza I, Manzoli L, Divecha N. Exploring the controversial role of PI3K signalling in CD4 + regulatory T (T-Reg) cells. Adv Biol Regul 2020; 76:100722. [PMID: 32362560 DOI: 10.1016/j.jbior.2020.100722] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/10/2020] [Accepted: 04/16/2020] [Indexed: 02/07/2023]
Abstract
The immune system is a complex network that acts to protect vertebrates from foreign microorganisms and carries out immunosurveillance to combat cancer. In order to avoid hyper-activation of the immune system leading to collateral damage tissues and organs and to prevent self-attack, the network has the intrinsic control mechanisms that negatively regulate immune responses. Central to this negative regulation are regulatory T (T-Reg) cells, which through cytokine secretion and cell interaction limit uncontrolled clonal expansion and functions of activated immune cells. Given that positive or negative manipulation of T-Regs activity could be utilised to therapeutically treat host versus graft rejection or cancer respectively, understanding how signaling pathways impact on T-Regs function should reveal potential targets with which to intervene. The phosphatidylinositol-3-kinase (PI3K) pathway controls a vast array of cellular processes and is critical in T cell activation. Here we focus on phosphoinositide 3-kinases (PI3Ks) and their ability to regulate T-Regs cell differentiation and function.
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Affiliation(s)
- Alessandro Poli
- The FIRC Institute of Molecular Oncology (IFOM), 20139, Milan, Italy
| | - Roberta Fiume
- Department of Biomedical Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy.
| | - Sara Mongiorgi
- Department of Biomedical Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Antonio Zaurito
- Center for Translational Cancer Research (TranslaTUM), Klinikum Rechts der Isar, Technische Universität München, 81675, Munich, Germany
| | - Bhavwanti Sheth
- Inositide Laboratory, School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Life Sciences Building 85, Highfield, Southampton, SO17 1BJ, UK
| | - Magdalena Castellano Vidalle
- Inositide Laboratory, School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Life Sciences Building 85, Highfield, Southampton, SO17 1BJ, UK
| | - Shidqiyyah Abdul Hamid
- Inositide Laboratory, School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Life Sciences Building 85, Highfield, Southampton, SO17 1BJ, UK
| | - ScottT Kimber
- Inositide Laboratory, School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Life Sciences Building 85, Highfield, Southampton, SO17 1BJ, UK
| | - Francesca Campagnoli
- Inositide Laboratory, School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Life Sciences Building 85, Highfield, Southampton, SO17 1BJ, UK
| | - Stefano Ratti
- Department of Biomedical Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Isabella Rusciano
- Department of Biomedical Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Irene Faenza
- Department of Biomedical Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Lucia Manzoli
- Department of Biomedical Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Nullin Divecha
- Inositide Laboratory, School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Life Sciences Building 85, Highfield, Southampton, SO17 1BJ, UK
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Stefan CJ. Endoplasmic reticulum-plasma membrane contacts: Principals of phosphoinositide and calcium signaling. Curr Opin Cell Biol 2020; 63:125-34. [PMID: 32088611 DOI: 10.1016/j.ceb.2020.01.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/18/2020] [Accepted: 01/20/2020] [Indexed: 12/29/2022]
Abstract
The endoplasmic reticulum (ER) forms an extensive network of membrane contact sites with intra-cellular organelles and the plasma membrane (PM). Interorganelle contacts have vital roles in membrane lipid and ion dynamics. In particular, ER-PM contacts are integral to numerous inter-cellular and intra-cellular signaling pathways including phosphoinositide lipid and calcium signaling, mechanotransduction, metabolic regulation, and cell stress responses. Accordingly, ER-PM contacts serve important signaling functions in excitable cells including neurons and muscle and endocrine cells. This review highlights recent advances in our understanding of the vital roles for ER-PM contacts in phosphoinositide and calcium signaling and how signaling pathways in turn regulate proteins that form and function at ER-PM contacts.
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Prieto JA, Estruch F, Córcoles-Sáez I, Del Poeta M, Rieger R, Stenzel I, Randez-Gil F. Pho85 and PI(4,5)P 2 regulate different lipid metabolic pathways in response to cold. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158557. [PMID: 31678512 PMCID: PMC7254492 DOI: 10.1016/j.bbalip.2019.158557] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/25/2019] [Accepted: 10/26/2019] [Indexed: 12/11/2022]
Abstract
Lipid homeostasis allows cells to adjust membrane biophysical properties in response to changes in environmental conditions. In the yeast Saccharomyces cerevisiae, a downward shift in temperature from an optimal reduces membrane fluidity, which triggers a lipid remodeling of the plasma membrane. How changes in membrane fluidity are perceived, and how the abundance and composition of different lipid classes is properly balanced, remain largely unknown. Here, we show that the levels of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], the most abundant plasma membrane phosphoinositide, drop rapidly in response to a downward shift in temperature. This change triggers a signaling cascade transmitted to cytosolic diphosphoinositol phosphate derivatives, among them 5-PP-IP4 and 1-IP7, that exert regulatory functions on genes involved in the inositol and phospholipids (PLs) metabolism, and inhibit the activity of the protein kinase Pho85. Consistent with this, cold exposure triggers a specific program of neutral lipids and PLs changes. Furthermore, we identified Pho85 as playing a key role in controlling the synthesis of long-chain bases (LCBs) via the Ypk1-Orm2 regulatory circuit. We conclude that Pho85 orchestrates a coordinated response of lipid metabolic pathways that ensure yeast thermal adaptation.
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Affiliation(s)
- Jose A Prieto
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain
| | - Francisco Estruch
- Departament of Biochemistry and Molecular Biology, Universitat de València, Dr. Moliner 50, Burjassot 46100, Spain
| | - Isaac Córcoles-Sáez
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States of America; Veterans Administration Medical Center, Northport, NY, United States of America
| | - Robert Rieger
- Proteomics Center, Stony Brook University, Stony Brook, NY, United States of America
| | - Irene Stenzel
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany
| | - Francisca Randez-Gil
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain.
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36
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Abstract
The multitudinous inositol phosphate family elicits a wide range of molecular effects that regulate countless biological responses. In this review, I provide a methodological viewpoint of the manner in which key advances in the field of inositol phosphate research were made. I also note some of the considerable challenges that still lie ahead.
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Affiliation(s)
- Stephen B Shears
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA.
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37
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Donia T, Jyoti B, Suizu F, Hirata N, Tanaka T, Ishigaki S, F PTJ, Nio-Kobayashi J, Iwanaga T, Chiorini JA, Noguchi M. Identification of RNA aptamer which specifically interacts with PtdIns(3)P. Biochem Biophys Res Commun 2019; 517:146-154. [PMID: 31351587 DOI: 10.1016/j.bbrc.2019.07.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 07/10/2019] [Indexed: 12/11/2022]
Abstract
The phosphinositide PtdIns(3)P plays an important role in autophagy; however, the detailed mechanism of its activity remains unclear. Here, we used a Systematic Evolution of Ligands by EXponential enrichment (SELEX) screening approach to identify an RNA aptamer of 40 nucleotides that specifically recognizes and binds to intracellular lysosomal PtdIns(3)P. Binding occurs in a magnesium concentration- and pH-dependent manner, and consequently inhibits autophagy as determined by LC3II/I conversion, p62 degradation, formation of LC3 puncta, and lysosomal accumulation of Phafin2. These effects in turn inhibited lysosomal acidification, and the subsequent hydrolytic activity of cathepsin D following induction of autophagy. Given the essential role of PtdIns(3)P as a key targeting molecule for autophagy induction, identification of this novel PtdIns(3)P RNA aptamer provides new opportunities for investigating the biological functions and mechanisms of phosphoinositides.
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Affiliation(s)
- Thoria Donia
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan; Chemistry Department, Faculty of Science, Tanta University, Egypt
| | - Bala Jyoti
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan; Molsys Scientific, 01 Kogilu, Mittiganahalli cross Yelahanka, Bangalore, 560064, India
| | - Futoshi Suizu
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Noriyuki Hirata
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Tsutomu Tanaka
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan; National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - Satoko Ishigaki
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Pranzatelli Thomas J F
- National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - Junko Nio-Kobayashi
- Laboratory of Histology and Cytology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Toshihiko Iwanaga
- Laboratory of Histology and Cytology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - John A Chiorini
- National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - Masayuki Noguchi
- Division of Cancer Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan.
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38
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Jun YW, Lee JA, Jang DJ. Novel GFP-fused protein probes for detecting phosphatidylinositol-4-phosphate in the plasma membrane. Anim Cells Syst (Seoul) 2019; 23:164-169. [PMID: 31231579 PMCID: PMC6567041 DOI: 10.1080/19768354.2019.1599424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 03/12/2019] [Accepted: 03/20/2019] [Indexed: 10/27/2022] Open
Abstract
Phosphatidylinositol-4-phosphate (PI4P) plays a crucial role in cellular functions, including protein trafficking, and is mainly located in the cytoplasmic surface of intracellular membranes, which include the trans-Golgi network (TGN) and the plasma membrane. However, many PI4P-binding domains of membrane-associated proteins are localized only to the TGN because of the requirement of a second binding protein such as ADP-ribosylation factor 1 (ARF1) in order to be stably localized to the specific membrane. In this study, we developed new probes that were capable of detecting PI4P at the plasma membrane using the known TGN-targeting PI4P-binding domains. The PI4P-specific binding pleckstrin homology (PH) domain of various proteins including CERT, OSBP, OSH1, and FAPP1 was combined with the N-terminal moderately hydrophobic domain of the short-form of Aplysia phosphodiesterase 4 (S(N30)), which aids in plasma membrane association but cannot alone facilitate this association. As a result, we found that the addition of S(N30) to the N-terminus of the GFP-fused PH domain of OSBP (S(N30)-GFP-OSBP-PH), OSH1 (S(N30)-GFP-OSH1-PH), or FAPP1 (S(N30)-GFP-FAPP1-PH) could induce plasma membrane localization, as well as retain TGN localization. The plasma membrane localization of S(N30)-GFP-FAPP1-PH is mediated by PI4P binding only, whereas those of S(N30)-GFP-OSBP-PH and S(N30)-GFP-OSH1-PH are mediated by either PI4P or PI(4,5)P2 binding. Taken together, we developed new probes that detect PI4P at the plasma membrane using a combination of a moderately hydrophobic domain with the known TGN-targeting PI4P-specific binding PH domain.
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Affiliation(s)
- Yong-Woo Jun
- Department of Ecological Science, College of Ecology and Environment, Kyungpook National University, Sangju-si, Republic of Korea
| | - Jin-A Lee
- Department of Biological Science and Biotechnology, College of Life Science and Nano Technology, Hannam University, Daejeon, Republic of Korea
| | - Deok-Jin Jang
- Department of Ecological Science, College of Ecology and Environment, Kyungpook National University, Sangju-si, Republic of Korea
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39
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Abstract
Polyphosphoinositides (PPIn) are essential signaling phospholipids that make remarkable contributions to the identity of all cellular membranes and signaling cascades in mammalian cells. They exert regulatory control over membrane homeostasis via selective interactions with cellular proteins at the membrane–cytoplasm interface. This review article briefly summarizes our current understanding of the key roles that PPIn play in orchestrating and regulating crucial electrical and chemical signaling events in mammalian neurons and the significant neuro-pathophysiological conditions that arise following alterations in their metabolism.
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Affiliation(s)
- Eamonn James Dickson
- Department Physiology and Membrane Biology, University of California, Davis, CA, 95616, USA
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40
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Bissig C, Croisé P, Heiligenstein X, Hurbain I, Lenk GM, Kaufman E, Sannerud R, Annaert W, Meisler MH, Weisman LS, Raposo G, van Niel G. The PIKfyve complex regulates the early melanosome homeostasis required for physiological amyloid formation. J Cell Sci 2019; 132:jcs.229500. [PMID: 30709920 DOI: 10.1242/jcs.229500] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 01/14/2019] [Indexed: 12/23/2022] Open
Abstract
The metabolism of PI(3,5)P2 is regulated by the PIKfyve, VAC14 and FIG4 complex, mutations in which are associated with hypopigmentation in mice. These pigmentation defects indicate a key, but as yet unexplored, physiological relevance of this complex in the biogenesis of melanosomes. Here, we show that PIKfyve activity regulates formation of amyloid matrix composed of PMEL protein within the early endosomes in melanocytes, called stage I melanosomes. PIKfyve activity controls the membrane remodeling of stage I melanosomes, which regulates PMEL abundance, sorting and processing. PIKfyve activity also affects stage I melanosome kiss-and-run interactions with lysosomes, which are required for PMEL amyloidogenesis and the establishment of melanosome identity. Mechanistically, PIKfyve activity promotes both the formation of membrane tubules from stage I melanosomes and their release by modulating endosomal actin branching. Taken together, our data indicate that PIKfyve activity is a key regulator of the melanosomal import-export machinery that fine tunes the formation of functional amyloid fibrils in melanosomes and the maintenance of melanosome identity.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Christin Bissig
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France
| | - Pauline Croisé
- IPNP, Institute of Psychiatry and Neuroscience of Paris, Hopital Saint-Anne, Université Paris Descartes, INSERM U894, 75014 Paris, France
| | - Xavier Heiligenstein
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France.,Cell and Tissue Imaging Facility, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France
| | - Ilse Hurbain
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France.,Cell and Tissue Imaging Facility, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France
| | - Guy M Lenk
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109-5618, USA
| | - Emily Kaufman
- Life Science Institute, University of Michigan, Ann Arbor, MI 48109-2216, USA
| | - Ragna Sannerud
- VIB Center for Brain & Disease Research, 3000 Leuven, Belgium.,KU Leuven, Department of Neurosciences, 3000 Leuven, Belgium
| | - Wim Annaert
- VIB Center for Brain & Disease Research, 3000 Leuven, Belgium.,KU Leuven, Department of Neurosciences, 3000 Leuven, Belgium
| | - Miriam H Meisler
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109-5618, USA
| | - Lois S Weisman
- Life Science Institute, University of Michigan, Ann Arbor, MI 48109-2216, USA
| | - Graça Raposo
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France.,Cell and Tissue Imaging Facility, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France
| | - Guillaume van Niel
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France .,IPNP, Institute of Psychiatry and Neuroscience of Paris, Hopital Saint-Anne, Université Paris Descartes, INSERM U894, 75014 Paris, France.,Cell and Tissue Imaging Facility, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, UMR144, 75005 Paris, France
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41
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Tóth JT, Gulyás G, Hunyady L, Várnai P. Development of Nonspecific BRET-Based Biosensors to Monitor Plasma Membrane Inositol Lipids in Living Cells. Methods Mol Biol 2019; 1949:23-34. [PMID: 30790246 DOI: 10.1007/978-1-4939-9136-5_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
There are several difficulties to face when investigating the role of phosphoinositides. Although they are present in most organelles, their concentration is very low, sometimes undetectable with the available methods; moreover, their level can quickly change upon several external stimuli. Here we introduce a newly improved lipid sensor tool-set based on the balanced expression of luciferase-fused phosphoinositide recognizing protein domains and a Venus protein targeted to the plasma membrane, allowing us to perform Bioluminescence Resonance Energy Transfer (BRET) measurements that reflect phosphoinositide changes in a population of transiently transfected cells. This method is highly sensitive, specific, and capable of semiquantitative characterization of plasma membrane phosphoinositide changes with high temporal resolution.
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Affiliation(s)
- József T Tóth
- Faculty of Medicine, Department of Physiology, Semmelweis University, Budapest, Hungary.,Faculty of Medicine, Department of Anesthesiology and Intensive Therapy, Semmelweis University, Budapest, Hungary
| | - Gergő Gulyás
- Faculty of Medicine, Department of Physiology Semmelweis University, Budapest, Hungary
| | - László Hunyady
- Faculty of Medicine, Department of Physiology, Semmelweis University, Budapest, Hungary.,MTA-SE Laboratory of Molecular Physiology, Budapest, Hungary
| | - Péter Várnai
- Faculty of Medicine, Department of Physiology, Semmelweis University, Budapest, Hungary. .,MTA-SE Laboratory of Molecular Physiology, Budapest, Hungary.
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42
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Koponen A, Arora A, Takahashi K, Kentala H, Kivelä AM, Jääskeläinen E, Peränen J, Somerharju P, Ikonen E, Viitala T, Olkkonen VM. ORP2 interacts with phosphoinositides and controls the subcellular distribution of cholesterol. Biochimie 2018; 158:90-101. [PMID: 30590084 DOI: 10.1016/j.biochi.2018.12.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 12/20/2018] [Indexed: 01/06/2023]
Abstract
ORP2 is a sterol-binding protein with documented functions in lipid and glucose metabolism, Akt signaling, steroidogenesis, cell adhesion, migration and proliferation. Here we investigate the interactions of ORP2 with phosphoinositides (PIPs) by surface plasmon resonance (SPR), its affinity for cholesterol with a pull-down assay, and its capacity to transfer sterol in vitro. Moreover, we determine the effects of wild-type (wt) ORP2 and a mutant with attenuated PIP binding, ORP2(mHHK), on the subcellular distribution of cholesterol, and analyze the interaction of ORP2 with the related cholesterol transporter ORP1L. ORP2 showed specific affinity for PI(4,5)P2, PI(3,4,5)P3 and PI(4)P, with suggestive Kd values in the μM range. Also binding of cholesterol by ORP2 was detectable, but a Kd could not be determined. Wt ORP2 was in HeLa cells mainly detected in the cytosol, ER, late endosomes, and occasionally on lipid droplets (LDs), while ORP2(mHHK) displayed an enhanced LD localization. Overexpression of wt ORP2 shifted the D4H cholesterol probe away from endosomes, while ORP2(mHHK) caused endosomal accumulation of the probe. Although ORP2 failed to transfer dehydroergosterol in an in vitro assay where OSBP is active, its knock-down resulted in the accumulation of cholesterol in late endocytic compartments, as detected by both D4H and filipin probes. Interestingly, ORP2 was shown to interact and partially co-localize on late endosomes with ORP1L, a cholesterol transporter/sensor at ER-late endosome junctions. Our data demonstrates that ORP2 binds several phosphoinositides, both PI(4)P and multiply phosphorylated species. ORP2 regulates the subcellular distribution of cholesterol dependent on its PIP-binding capacity. The interaction of ORP2 with ORP1L suggests a concerted action of the two ORPs.
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Affiliation(s)
- Annika Koponen
- Minerva Foundation Institute for Medical Research, Biomedicum 2U, FI-00290, Helsinki, Finland
| | - Amita Arora
- Minerva Foundation Institute for Medical Research, Biomedicum 2U, FI-00290, Helsinki, Finland
| | - Kohta Takahashi
- Department of Anatomy, Faculty of Medicine, FI-00014, University of Helsinki, Finland
| | - Henriikka Kentala
- Minerva Foundation Institute for Medical Research, Biomedicum 2U, FI-00290, Helsinki, Finland
| | - Annukka M Kivelä
- Minerva Foundation Institute for Medical Research, Biomedicum 2U, FI-00290, Helsinki, Finland
| | - Eeva Jääskeläinen
- Minerva Foundation Institute for Medical Research, Biomedicum 2U, FI-00290, Helsinki, Finland
| | - Johan Peränen
- Department of Anatomy, Faculty of Medicine, FI-00014, University of Helsinki, Finland
| | - Pentti Somerharju
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, FI-00014, University of Helsinki, Finland
| | - Elina Ikonen
- Department of Anatomy, Faculty of Medicine, FI-00014, University of Helsinki, Finland
| | - Tapani Viitala
- Drug Research Program, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, FI-00014, University of Helsinki, Finland
| | - Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research, Biomedicum 2U, FI-00290, Helsinki, Finland; Department of Anatomy, Faculty of Medicine, FI-00014, University of Helsinki, Finland.
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43
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Davies EM, Gurung R, Le KQ, Mitchell CA. Effective angiogenesis requires regulation of phosphoinositide signaling. Adv Biol Regul 2019; 71:69-78. [PMID: 30503054 DOI: 10.1016/j.jbior.2018.11.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 11/22/2018] [Accepted: 11/22/2018] [Indexed: 12/21/2022]
Abstract
Phosphoinositide signaling regulates numerous downstream effectors that mediate cellular processes which influence cell cycle progression, migration, proliferation, growth, survival, metabolism and vesicular trafficking. A prominent role for phosphoinositide 3-kinase, which generates phosphatidylinositol 3,4,5-trisphosphate, a phospholipid that activates a plethora of effectors including AKT and FOXO during embryonic and postnatal angiogenesis, has been described. In addition, phosphatidylinositol 3-phosphate signaling is required for endosomal trafficking, which contributes to vascular remodeling. This review will examine the role phosphoinositide signaling plays in the endothelium and its contribution to sprouting angiogenesis.
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44
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Arellanes-Robledo J, Reyes-Gordillo K, Ibrahim J, Leckey L, Shah R, Lakshman MR. Ethanol targets nucleoredoxin/dishevelled interactions and stimulates phosphatidylinositol 4-phosphate production in vivo and in vitro. Biochem Pharmacol 2018; 156:135-146. [PMID: 30125555 DOI: 10.1016/j.bcp.2018.08.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/16/2018] [Indexed: 02/07/2023]
Abstract
Nucleoredoxin (NXN) is a redox-regulating protein potentially targeted by reactive oxygen species (ROS). It regulates molecular pathways that participate in several key cellular processes. However, the role of NXN in the alcohol liver disease (ALD) redox regulation has not been fully understood. Here, we investigated the effects of ethanol and ethanol plus lipopolysaccharide, a two-hit liver injury model (Ethanol/LPS), on NXN/dishevelled (DVL) interaction and on DVL-dependent phosphoinositides production both in mouse liver and in a co-culture system consisting of human hepatic stellate cells (HSC) and ethanol metabolizing-VL17A human hepatocyte cells. Ethanol and two-hit model increased Nxn protein and mRNA expression, and 4-hydroxynonenal adducts. Two-hit model promoted Nxn nuclear translocation and Dvl/Phosphatidylinositol 4-kinase type-IIα (Pi4k2a) interaction ratio but surprisingly decreased Dvl protein and mRNA levels and reverted ethanol-induced Nxn/Dvl and Dvl/frizzled (Fzd) interaction ratios. Ethanol resulted in a significant increase of Dvl protein and mRNA expression, and decreased Nxn/Dvl interaction ratio but promoted the interaction of Dvl with Fzd and Pi4k2a; formation of this complex induced phosphatidylinositol 4-phosphate [PI(4)P] production. Ethanol and LPS treatments provoked similar alterations on NXN/DVL interaction and its downstream effect in HSC/VL17A co-culture system. Interestingly, ROS and glutathione levels as well as most of ethanol-induced alterations were modified by NXN overexpression in the co-culture system. In conclusion, two-hit model of ethanol exposure disrupts NXN/DVL homeostatic status to allow DVL/FZD/PI4K2A complex formation and stimulates PI(4)P production. These results provide a new mechanism showing that NXN also participates in the regulation of phosphoinositides production that is altered by ethanol during alcoholic liver disease progression.
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Affiliation(s)
- Jaime Arellanes-Robledo
- Lipid Research Laboratory, VA Medical Center, Department of Biochemistry and Molecular Medicine, The George Washington University Medical Center, Washington, D.C., USA; Laboratory of Hepatic Diseases, National Institute of Genomic Medicine - INMEGEN, CDMX, Mexico; National Council of Science and Technology - CONACYT, CDMX, Mexico.
| | - Karina Reyes-Gordillo
- Lipid Research Laboratory, VA Medical Center, Department of Biochemistry and Molecular Medicine, The George Washington University Medical Center, Washington, D.C., USA.
| | - Joseph Ibrahim
- Lipid Research Laboratory, VA Medical Center, Department of Biochemistry and Molecular Medicine, The George Washington University Medical Center, Washington, D.C., USA
| | - Leslie Leckey
- Lipid Research Laboratory, VA Medical Center, Department of Biochemistry and Molecular Medicine, The George Washington University Medical Center, Washington, D.C., USA
| | - Ruchi Shah
- Lipid Research Laboratory, VA Medical Center, Department of Biochemistry and Molecular Medicine, The George Washington University Medical Center, Washington, D.C., USA
| | - M Raj Lakshman
- Lipid Research Laboratory, VA Medical Center, Department of Biochemistry and Molecular Medicine, The George Washington University Medical Center, Washington, D.C., USA
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45
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Kim EC, Zhang J, Pang W, Wang S, Lee KY, Cavaretta JP, Walters J, Procko E, Tsai NP, Chung HJ. Reduced axonal surface expression and phosphoinositide sensitivity in K v7 channels disrupts their function to inhibit neuronal excitability in Kcnq2 epileptic encephalopathy. Neurobiol Dis 2018; 118:76-93. [PMID: 30008368 DOI: 10.1016/j.nbd.2018.07.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 06/22/2018] [Accepted: 07/04/2018] [Indexed: 01/08/2023] Open
Abstract
Neuronal Kv7/KCNQ channels are voltage-gated potassium channels composed of Kv7.2/KCNQ2 and Kv7.3/KCNQ3 subunits. Enriched at the axonal membrane, they potently suppress neuronal excitability. De novo and inherited dominant mutations in Kv7.2 cause early onset epileptic encephalopathy characterized by drug resistant seizures and profound psychomotor delay. However, their precise pathogenic mechanisms remain elusive. Here, we investigated selected epileptic encephalopathy causing mutations in calmodulin (CaM)-binding helices A and B of Kv7.2. We discovered that R333W, K526N, and R532W mutations located peripheral to CaM contact sites decreased axonal surface expression of heteromeric channels although only R333W mutation reduced CaM binding to Kv7.2. These mutations also altered gating modulation by phosphatidylinositol 4,5-bisphosphate (PIP2), revealing novel PIP2 binding residues. While these mutations disrupted Kv7 function to suppress excitability, hyperexcitability was observed in neurons expressing Kv7.2-R532W that displayed severe impairment in voltage-dependent activation. The M518 V mutation at the CaM contact site in helix B caused most defects in Kv7 channels by severely reducing their CaM binding, K+ currents, and axonal surface expression. Interestingly, the M518 V mutation induced ubiquitination and accelerated proteasome-dependent degradation of Kv7.2, whereas the presence of Kv7.3 blocked this degradation. Furthermore, expression of Kv7.2-M518V increased neuronal death. Together, our results demonstrate that epileptic encephalopathy mutations in helices A and B of Kv7.2 cause abnormal Kv7 expression and function by disrupting Kv7.2 binding to CaM and/or modulation by PIP2. We propose that such multiple Kv7 channel defects could exert more severe impacts on neuronal excitability and health, and thus serve as pathogenic mechanisms underlying Kcnq2 epileptic encephalopathy.
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Affiliation(s)
- Eung Chang Kim
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jiaren Zhang
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Weilun Pang
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Shuwei Wang
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Kwan Young Lee
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - John P Cavaretta
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jennifer Walters
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Erik Procko
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Nien-Pei Tsai
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Hee Jung Chung
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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46
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Choi S, Houdek X, Anderson RA. Phosphoinositide 3-kinase pathways and autophagy require phosphatidylinositol phosphate kinases. Adv Biol Regul 2018; 68:31-38. [PMID: 29472147 PMCID: PMC5955796 DOI: 10.1016/j.jbior.2018.02.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 02/07/2018] [Accepted: 02/07/2018] [Indexed: 01/10/2023]
Abstract
Phosphatidylinositol phosphate kinases (PIPKs) generate a lipid messenger phosphatidylinositol 4,5-bisphosphate (PI4,5P2) that controls essentially all aspects of cellular functions. PI4,5P2 rapidly diffuses in the membrane of the lipid bilayer and does not greatly change in membrane or cellular content, and thus PI4,5P2 generation by PIPKs is tightly linked to its usage in subcellular compartments. Based on this verity, recent study of PI4,5P2 signal transduction has been focused on investigations of individual PIPKs and their underlying molecular regulation of cellular processes. Here, we will discuss recent advances in the study of how PIPKs control specific cellular events through assembly and regulation of PI4,5P2 effectors that mediate specific cellular processes. A focus will be on the roles of PIPKs in control of the phosphoinositide 3-kinase pathway and autophagy.
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Affiliation(s)
- Suyong Choi
- University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Xander Houdek
- University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Richard A Anderson
- University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA.
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47
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Martinez D, Prouzet-Mauléon V, Hugues M, Doignon F, Odaert B. Assignment of 1H, 13C and 15N resonances and secondary structure of the Rgd1-RhoGAP domain. Biomol NMR Assign 2018; 12:129-132. [PMID: 29280056 DOI: 10.1007/s12104-017-9794-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/16/2017] [Indexed: 06/07/2023]
Abstract
The protein Rgd1 is involved in the regulation of cytoskeleton formation and in signalling pathways that control cell polarity and growth in Saccharomyces cerevisiae. Rgd1p is composed of a F-BAR domain required for membrane binding and a RhoGAP domain responsible for activating Rho3p and Rho4p, two GTPases respectively involved in bud growth and cytokinesis. Rgd1p is recruited to the membrane through interactions with phosphoinositide lipids, which bind the two isolated domains and stimulate the RhoGAP activity on Rho4p. As previously shown by crystallography, the membrane-binding F-BAR domain contains a conserved inositol phosphate binding site, which explains the preferential binding of phosphoinositides. In contrast, RhoGAP domains are not expected to bind lipids. In order to unravel this puzzling feature, we solved the three-dimensional structure of the isolated protein and found a cryptic phosphoinositide binding site involving non conserved residues (Martinez et al. 2017). The assignment of the resonances and secondary structure of Rgd1-RhoGAP (aa 450-666) is presented here.
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Affiliation(s)
- Denis Martinez
- Chimie et Biologie des Membranes et des Nano-objets, Université de Bordeaux, CNRS UMR 5248, Allée Geoffroy Saint Hilaire, 33600, Pessac Cedex, France
| | - Valérie Prouzet-Mauléon
- Laboratoire d'Hématopoïèse Leucémique et Cibles Thérapeutiques, Université de Bordeaux, INSERM 1035, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France
| | - Michel Hugues
- Chimie et Biologie des Membranes et des Nano-objets, Université de Bordeaux, CNRS UMR 5248, Allée Geoffroy Saint Hilaire, 33600, Pessac Cedex, France
| | - François Doignon
- Laboratoire de Biogenèse Membranaire, Université de Bordeaux, CNRS UMR 5200, 71 Avenue Edouard Bourlaux, 33883, Villenave d'Ornon Cedex, France
| | - Benoît Odaert
- Chimie et Biologie des Membranes et des Nano-objets, Université de Bordeaux, CNRS UMR 5248, Allée Geoffroy Saint Hilaire, 33600, Pessac Cedex, France.
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48
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Abstract
The growth and proliferation of metazoan cells are driven by cellular nutrient status and by extracellular growth factors. Growth factor receptors on cell surfaces initiate biochemical signals that increase anabolic metabolism and macropinocytosis, an actin-dependent endocytic process in which relatively large volumes of extracellular solutes and nutrients are internalized and delivered efficiently into lysosomes. Macropinocytosis is prominent in many kinds of cancer cells, and supports the growth of cells transformed by oncogenic K-Ras. Growth factor receptor signaling and the overall metabolic status of the cell are coordinated in the cytoplasm by the mechanistic target-of-rapamycin complex-1 (mTORC1), which positively regulates protein synthesis and negatively regulates molecular salvage pathways such as autophagy. mTORC1 is activated by two distinct Ras-related small GTPases, Rag and Rheb, which associate with lysosomal membranes inside the cell. Rag recruits mTORC1 to the lysosomal surface where Rheb directly binds to and activates mTORC1. Rag is activated by both lysosomal luminal and cytosolic amino acids; Rheb activation requires phosphoinositide 3-kinase, Akt, and the tuberous sclerosis complex-1/2. Signals for activation of Rag and Rheb converge at the lysosomal membrane, and several lines of evidence support the idea that growth factor-dependent endocytosis facilitates amino acid transfer into the lysosome leading to the activation of Rag. This review summarizes evidence that growth factor-stimulated macropinocytosis is essential for amino acid-dependent activation of mTORC1, and that increased solute accumulation by macropinocytosis in transformed cells supports unchecked cell growth.
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Affiliation(s)
- Sei Yoshida
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109-5620, USA
| | - Regina Pacitto
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109-5620, USA
| | - Ken Inoki
- Department of Integrative and Molecular Physiology and Internal Medicine, Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Joel Swanson
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109-5620, USA.
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Wengelnik K, Daher W, Lebrun M. Phosphoinositides and their functions in apicomplexan parasites. Int J Parasitol 2018; 48:493-504. [PMID: 29596862 DOI: 10.1016/j.ijpara.2018.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 01/26/2018] [Accepted: 01/29/2018] [Indexed: 11/28/2022]
Abstract
Phosphoinositides are the phosphorylated derivatives of the structural membrane phospholipid phosphatidylinositol. Single or combined phosphorylation at the 3, 4 and 5 positions of the inositol ring gives rise to the seven different species of phosphoinositides. All are quantitatively minor components of cellular membranes but have been shown to have important functions in multiple cellular processes. Here we describe our current knowledge of phosphoinositide metabolism and functions in apicomplexan parasites, mainly focusing on Toxoplasma gondii and Plasmodium spp. Even though our understanding is still rudimentary, phosphoinositides have already shown their importance in parasite biology and revealed some very particular and parasite-specific functions. Not surprisingly, there is a strong potential for phosphoinositide synthesis to be exploited for future anti-parasitic drug development.
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Affiliation(s)
- Kai Wengelnik
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS, INSERM, Université Montpellier, Montpellier, France.
| | - Wassim Daher
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS, INSERM, Université Montpellier, Montpellier, France
| | - Maryse Lebrun
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS, INSERM, Université Montpellier, Montpellier, France.
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50
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Abstract
PTEN is a one of the most frequently mutated tumor suppressors in human cancers. It is essential for regulating diverse biological processes and through its lipid phosphatase activity regulates the PI 3-Kinase signaling pathway. Sensitive phosphatase assays are employed to study the catalytic activity of PTEN against phospholipid substrates. Here we describe protocols to assay PTEN lipid phosphatase activity using either purified enzyme (purified PTEN lipid phosphatase assay) or PTEN immunopurified from tissues or cultured cells (cellular IP PTEN lipid phosphatase assay) against vesicles containing radiolabeled PIP3 substrate.
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Affiliation(s)
- Laura Spinelli
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot Watt University, Nasmyth Building, Riccarton Campus, Edinburgh, EH14 4AS, UK
- Division of Cell Signalling and Immunology, School of Life Sciences, University of Dundee, Dundee, UK
| | - Nicholas R Leslie
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot Watt University, Nasmyth Building, Riccarton Campus, Edinburgh, EH14 4AS, UK.
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