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Zuo W, Tian M, Qi J, Zhang G, Hu J, Wang S, Bao Y. The functions of EF-hand proteins from host and zoonotic pathogens. Microbes Infect 2023:105276. [PMID: 38072184 DOI: 10.1016/j.micinf.2023.105276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023]
Abstract
EF-hand proteins not only regulate biological processes, but also influence immunity and infection. In this review, we summarize EF-hand proteins' functions in host and zoonotic pathogens, with details in structures, Ca2+ affinity, downstream targets and functional mechanisms. Studies entitled as EF-hand-related but with less solid features were also discussed. We believe it could raise cautions and facilitate proper research strategy for researchers.
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Affiliation(s)
- Wei Zuo
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Mingxing Tian
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Jingjing Qi
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Guangdong Zhang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Jiangang Hu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Shaohui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Engineering Research Center for the Prevention and Control of Animal Original Zoonosis of Fujian Province University, College of Life Science, Longyan University, Longyan, 364012, Fujian, China.
| | - Yanqing Bao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Engineering Research Center for the Prevention and Control of Animal Original Zoonosis of Fujian Province University, College of Life Science, Longyan University, Longyan, 364012, Fujian, China.
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2
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Márquez-Nogueras KM, Vuchkovska V, Kuo IY. Calcium signaling in polycystic kidney disease- cell death and survival. Cell Calcium 2023; 112:102733. [PMID: 37023534 PMCID: PMC10348384 DOI: 10.1016/j.ceca.2023.102733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/20/2023] [Accepted: 03/30/2023] [Indexed: 04/03/2023]
Abstract
Polycystic kidney disease is typified by cysts in the kidney and extra-renal manifestations including hypertension and heart failure. The main genetic underpinning this disease are loss-of function mutations to the two polycystin proteins, polycystin 1 and polycystin 2. Molecularly, the disease is characterized by changes in multiple signaling pathways including down regulation of calcium signaling, which, in part, is contributed by the calcium permeant properties of polycystin 2. These signaling pathways enable the cystic cells to survive and avoid cell death. This review focuses on the studies that have emerged in the past 5 years describing how the structural insights gained from PC-1 and PC-2 inform the calcium dependent molecular pathways of autophagy and the unfolded protein response that are regulated by the polycystin proteins and how it leads to cell survival and/or cell death.
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Affiliation(s)
- Karla M Márquez-Nogueras
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, 2160 S. First Ave, Maywood, IL, USA
| | - Virdjinija Vuchkovska
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, 2160 S. First Ave, Maywood, IL, USA; Graduate School, Loyola University Chicago, 2160 S. First Ave, Maywood, IL, USA
| | - Ivana Y Kuo
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, 2160 S. First Ave, Maywood, IL, USA.
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3
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Wang Y, Wang Z, Pavel MA, Ng C, Kashyap P, Li B, Morais TDC, Ulloa GA, Yu Y. The diverse effects of pathogenic point mutations on ion channel activity of a gain-of-function polycystin-2. J Biol Chem 2023; 299:104674. [PMID: 37028763 PMCID: PMC10192930 DOI: 10.1016/j.jbc.2023.104674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 02/27/2023] [Accepted: 03/06/2023] [Indexed: 04/08/2023] Open
Abstract
Autosomal dominant polycystic kidney disease is caused by mutations in PKD1 or PKD2 genes. The latter encodes polycystin-2 (PC2, also known as TRPP2), a member of the transient receptor potential ion channel family. Despite most pathogenic mutations in PKD2 being truncation variants, there are also many point mutations, which cause small changes in protein sequences but dramatic changes in the in vivo function of PC2. How these mutations affect PC2 ion channel function is largely unknown. In this study, we systematically tested the effects of 31 point mutations on the ion channel activity of a gain-of-function PC2 mutant, PC2_F604P, expressed in Xenopus oocytes. The results show that all mutations in the transmembrane domains and channel pore region, and most mutations in the extracellular tetragonal opening for polycystins domain, are critical for PC2_F604P channel function. In contrast, the other mutations in the tetragonal opening for polycystins domain and most mutations in the C-terminal tail cause mild or no effects on channel function as assessed in Xenopus oocytes. To understand the mechanism of these effects, we have discussed possible conformational consequences of these mutations based on the cryo-EM structures of PC2. The results help gain insight into the structure and function of the PC2 ion channel and the molecular mechanism of pathogenesis caused by these mutations.
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Affiliation(s)
- Yan Wang
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Zhifei Wang
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Mahmud Arif Pavel
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Courtney Ng
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Parul Kashyap
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Bin Li
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Tiago D C Morais
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Gabriella A Ulloa
- Department of Biological Sciences, St. John's University, Queens, New York, USA
| | - Yong Yu
- Department of Biological Sciences, St. John's University, Queens, New York, USA.
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4
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Cantero MDR, Cantiello HF. Polycystin-2 (TRPP2): Ion channel properties and regulation. Gene 2022; 827:146313. [PMID: 35314260 DOI: 10.1016/j.gene.2022.146313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/19/2022] [Accepted: 02/08/2022] [Indexed: 12/01/2022]
Abstract
Polycystin-2 (TRPP2, PKD2, PC2) is the product of the PKD2 gene, whose mutations cause Autosomal Dominant Polycystic Kidney Disease (ADPKD). PC2 belongs to the superfamily of TRP (Transient Receptor Potential) proteins that generally function as Ca2+-permeable nonselective cation channels implicated in Ca2+ signaling. PC2 localizes to various cell domains with distinct functions that likely depend on interactions with specific channel partners. Functions include receptor-operated, nonselective cation channel activity in the plasma membrane, intracellular Ca2+ release channel activity in the endoplasmic reticulum (ER), and mechanosensitive channel activity in the primary cilium of renal epithelial cells. Here we summarize our current understanding of the properties of PC2 and how other transmembrane and cytosolic proteins modulate this activity, providing functional diversity and selective regulatory mechanisms to its role in the control of cellular Ca2+ homeostasis.
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Affiliation(s)
- María Del Rocío Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), El Zanjón, Santiago del Estero 4206, Argentina.
| | - Horacio F Cantiello
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), El Zanjón, Santiago del Estero 4206, Argentina
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5
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Peña-Oyarzun D, Rodriguez-Peña M, Burgos-Bravo F, Vergara A, Kretschmar C, Sotomayor-Flores C, Ramirez-Sarmiento CA, De Smedt H, Reyes M, Perez W, Torres VA, Morselli E, Altamirano F, Wilson CAM, Hill JA, Lavandero S, Criollo A. PKD2/polycystin-2 induces autophagy by forming a complex with BECN1. Autophagy 2021; 17:1714-1728. [PMID: 32543276 PMCID: PMC8354594 DOI: 10.1080/15548627.2020.1782035] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 05/29/2020] [Accepted: 06/03/2020] [Indexed: 12/15/2022] Open
Abstract
Macroautophagy/autophagy is an intracellular process involved in the breakdown of macromolecules and organelles. Recent studies have shown that PKD2/PC2/TRPP2 (polycystin 2, transient receptor potential cation channel), a nonselective cation channel permeable to Ca2+ that belongs to the family of transient receptor potential channels, is required for autophagy in multiple cell types by a mechanism that remains unclear. Here, we report that PKD2 forms a protein complex with BECN1 (beclin 1), a key protein required for the formation of autophagic vacuoles, by acting as a scaffold that interacts with several co-modulators via its coiled-coil domain (CCD). Our data identified a physical and functional interaction between PKD2 and BECN1, which depends on one out of two CCD domains (CC1), located in the carboxy-terminal tail of PKD2. In addition, depletion of intracellular Ca2+ with BAPTA-AM not only blunted starvation-induced autophagy but also disrupted the PKD2-BECN1 complex. Consistently, PKD2 overexpression triggered autophagy by increasing its interaction with BECN1, while overexpression of PKD2D509V, a Ca2+ channel activity-deficient mutant, did not induce autophagy and manifested diminished interaction with BECN1. Our findings show that the PKD2-BECN1 complex is required for the induction of autophagy, and its formation depends on the presence of the CC1 domain of PKD2 and on intracellular Ca2+ mobilization by PKD2. These results provide new insights regarding the molecular mechanisms by which PKD2 controls autophagy.Abbreviations: ADPKD: autosomal dominant polycystic kidney disease; ATG: autophagy-related; ATG14/ATG14L: autophagy related 14; Baf A1: bafilomycin A1; BCL2/Bcl-2: BCL2 apoptosis regulator; BCL2L1/BCL-XL: BCL2 like 1; BECN1: beclin 1; CCD: coiled-coil domain; EBSS: Earle's balanced salt solution; ER: endoplasmic reticulum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; GOLGA2/GM130: golgin A2; GST: glutathione s-transferase; LAMP1: lysosomal associated membrane protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTORC1: mechanistic target of rapamycin kinase complex 1; NBR1: NBR1 autophagy cargo receptor; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; PKD2/PC2: polycystin 2, transient receptor potential cation channel; RTN4/NOGO: reticulon 4; RUBCN/RUBICON: rubicon autophagy regulator; SQSTM1/p62: sequestosome 1; UVRAG: UV radiation resistance associated; WIPI2: WD repeat domain, phosphoinositide interacting 2.
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Affiliation(s)
- Daniel Peña-Oyarzun
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Marcelo Rodriguez-Peña
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Francesca Burgos-Bravo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Angelo Vergara
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Catalina Kretschmar
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Cristian Sotomayor-Flores
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Cesar A. Ramirez-Sarmiento
- Institute for Biological and Medical Engineering, Facultades de Ingenieria, Medicina y Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Humbert De Smedt
- Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven, Belgium
| | - Montserrat Reyes
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Department of Pathology and Oral Medicine, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - William Perez
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
| | - Vicente A. Torres
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Eugenia Morselli
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Francisco Altamirano
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX, USA
| | - Christian A. M. Wilson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Joseph A. Hill
- Cardiology Division, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
- Cardiology Division, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Alfredo Criollo
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Autophagy Research Center, Universidad de Chile, Santiago, Chile
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6
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Márquez-Nogueras KM, Hortua Triana MA, Chasen NM, Kuo IY, Moreno SN. Calcium signaling through a transient receptor channel is important for Toxoplasma gondii growth. eLife 2021; 10:63417. [PMID: 34106044 PMCID: PMC8216714 DOI: 10.7554/elife.63417] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 06/08/2021] [Indexed: 12/24/2022] Open
Abstract
Transient receptor potential (TRP) channels participate in calcium ion (Ca2+) influx and intracellular Ca2+ release. TRP channels have not been studied in Toxoplasma gondii or any other apicomplexan parasite. In this work, we characterize TgGT1_310560, a protein predicted to possess a TRP domain (TgTRPPL-2), and determined its role in Ca2+ signaling in T. gondii, the causative agent of toxoplasmosis. TgTRPPL-2 localizes to the plasma membrane and the endoplasmic reticulum (ER) of T. gondii. The ΔTgTRPPL-2 mutant was defective in growth and cytosolic Ca2+ influx from both extracellular and intracellular sources. Heterologous expression of TgTRPPL-2 in HEK-3KO cells allowed its functional characterization. Patching of ER-nuclear membranes demonstrates that TgTRPPL-2 is a non-selective cation channel that conducts Ca2+. Pharmacological blockers of TgTRPPL-2 inhibit Ca2+ influx and parasite growth. This is the first report of an apicomplexan ion channel that conducts Ca2+ and may initiate a Ca2+ signaling cascade that leads to the stimulation of motility, invasion, and egress. TgTRPPL-2 is a potential target for combating toxoplasmosis.
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Affiliation(s)
- Karla Marie Márquez-Nogueras
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, United States.,Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, United States
| | | | - Nathan M Chasen
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, United States
| | - Ivana Y Kuo
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, United States
| | - Silvia Nj Moreno
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, United States.,Department of Cellular Biology, University of Georgia, Athens, United States
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7
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Polycystins as components of large multiprotein complexes of polycystin interactors. Cell Signal 2020; 72:109640. [PMID: 32305669 DOI: 10.1016/j.cellsig.2020.109640] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 04/14/2020] [Accepted: 04/14/2020] [Indexed: 12/27/2022]
Abstract
Naturally occurring mutations in two separate genes, PKD1 and PKD2, are responsible for the vast majority of all cases of autosomal dominant polycystic kidney disease (ADPKD), one of the most common genetic diseases affecting 1 in 1000 Americans. The hallmark of ADPKD is the development of epithelial cysts in the kidney, liver, and pancreas. PKD1 encodes a large plasma membrane protein (PKD1, PC1, or Polycystin-1) with a long extracellular domain and has been speculated to function as an atypical G protein coupled receptor. PKD2 encodes an ion channel of the Transient Receptor Potential superfamily (TRPP2, PKD2, PC2, or Polycystin-2). Despite the identification of these genes more than 20 years ago, the molecular function of their encoded proteins and the mechanism(s) by which mutations in PKD1 and PKD2 cause ADPKD remain elusive. Genetic, biochemical, and functional evidence suggests they form a multiprotein complex present in multiple locations in the cell, including the plasma membrane, endoplasmic reticulum, and the primary cilium. Over the years, numerous interacting proteins have been identified using directed and unbiased approaches, and shown to modulate function, cellular localization, and protein stability and turnover of Polycystins. Delineation of the molecular composition of the Polycystin complex can have a significant impact on understanding their cellular function in health and disease states and on the identification of more specific and effective therapeutic targets.
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8
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Abstract
Mutations in the polycystins PC1 or PC2 cause autosomal dominant polycystic kidney disease (ADPKD), which is characterized by the formation of fluid-filled renal cysts that disrupt renal architecture and function, ultimately leading to kidney failure in the majority of patients. Although the genetic basis of ADPKD is now well established, the physiological function of polycystins remains obscure and a matter of intense debate. The structural determination of both the homomeric PC2 and heteromeric PC1-PC2 complexes, as well as the electrophysiological characterization of PC2 in the primary cilium of renal epithelial cells, provided new valuable insights into the mechanisms of ADPKD pathogenesis. Current findings indicate that PC2 can function independently of PC1 in the primary cilium of renal collecting duct epithelial cells to form a channel that is mainly permeant to monovalent cations and is activated by both membrane depolarization and an increase in intraciliary calcium. In addition, PC2 functions as a calcium-activated calcium release channel at the endoplasmic reticulum membrane. Structural studies indicate that the heteromeric PC1-PC2 complex comprises one PC1 and three PC2 channel subunits. Surprisingly, several positively charged residues from PC1 occlude the ionic pore of the PC1-PC2 complex, suggesting that pathogenic polycystin mutations might cause ADPKD independently of an effect on channel permeation. Emerging reports of novel structural and functional findings on polycystins will continue to elucidate the molecular basis of ADPKD.
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9
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Brill AL, Ehrlich BE. Polycystin 2: A calcium channel, channel partner, and regulator of calcium homeostasis in ADPKD. Cell Signal 2019; 66:109490. [PMID: 31805375 DOI: 10.1016/j.cellsig.2019.109490] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/30/2019] [Accepted: 12/01/2019] [Indexed: 01/26/2023]
Abstract
Polycystin 2 (PC2) is one of two main protein types responsible for the underlying etiology of autosomal dominant polycystic kidney disease (ADPKD), the most prevalent monogenic renal disease in the world. This debilitating and currently incurable condition is caused by loss-of-function mutations in PKD2 and PKD1, the genes encoding for PC2 and Polycystin 1 (PC1), respectively. Two-hit mutation events in these genes lead to renal cyst formation and eventual kidney failure, the main hallmarks of ADPKD. Though much is known concerning the physiological consequences and dysfunctional signaling mechanisms resulting from ADPKD development, to best understand the requirement of PC2 in maintaining organ homeostasis, it is important to recognize how PC2 acts under normal conditions. As such, an array of work has been performed characterizing the endogenous function of PC2, revealing it to be a member of the transient receptor potential (TRP) channel family of proteins. As a TRP protein, PC2 is a nonselective, cation-permeant, calcium-sensitive channel expressed in all tissue types, where it localizes primarily on the endoplasmic reticulum (ER), primary cilia, and plasma membrane. In addition to its channel function, PC2 interacts with and acts as a regulator of a number of other channels, ultimately further affecting intracellular signaling and leading to dysfunction in its absence. In this review, we describe the biophysical and physiological properties of PC2 as a cation channel and modulator of intracellular calcium channels, along with how these properties are altered in ADPKD.
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Affiliation(s)
- Allison L Brill
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA
| | - Barbara E Ehrlich
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA; Department of Pharmacology, Yale University, New Haven, CT, USA.
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10
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TMEM33 regulates intracellular calcium homeostasis in renal tubular epithelial cells. Nat Commun 2019; 10:2024. [PMID: 31048699 PMCID: PMC6497644 DOI: 10.1038/s41467-019-10045-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 04/16/2019] [Indexed: 12/13/2022] Open
Abstract
Mutations in the polycystins cause autosomal dominant polycystic kidney disease (ADPKD). Here we show that transmembrane protein 33 (TMEM33) interacts with the ion channel polycystin-2 (PC2) at the endoplasmic reticulum (ER) membrane, enhancing its opening over the whole physiological calcium range in ER liposomes fused to planar bilayers. Consequently, TMEM33 reduces intracellular calcium content in a PC2-dependent manner, impairs lysosomal calcium refilling, causes cathepsins translocation, inhibition of autophagic flux upon ER stress, as well as sensitization to apoptosis. Invalidation of TMEM33 in the mouse exerts a potent protection against renal ER stress. By contrast, TMEM33 does not influence pkd2-dependent renal cystogenesis in the zebrafish. Together, our results identify a key role for TMEM33 in the regulation of intracellular calcium homeostasis of renal proximal convoluted tubule cells and establish a causal link between TMEM33 and acute kidney injury.
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11
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Zheng W, Yang X, Hu R, Cai R, Hofmann L, Wang Z, Hu Q, Liu X, Bulkley D, Yu Y, Tang J, Flockerzi V, Cao Y, Cao E, Chen XZ. Hydrophobic pore gates regulate ion permeation in polycystic kidney disease 2 and 2L1 channels. Nat Commun 2018; 9:2302. [PMID: 29899465 PMCID: PMC5998024 DOI: 10.1038/s41467-018-04586-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 05/01/2018] [Indexed: 01/20/2023] Open
Abstract
PKD2 and PKD1 genes are mutated in human autosomal dominant polycystic kidney disease. PKD2 can form either a homomeric cation channel or a heteromeric complex with the PKD1 receptor, presumed to respond to ligand(s) and/or mechanical stimuli. Here, we identify a two-residue hydrophobic gate in PKD2L1, and a single-residue hydrophobic gate in PKD2. We find that a PKD2 gain-of-function gate mutant effectively rescues PKD2 knockdown-induced phenotypes in embryonic zebrafish. The structure of a PKD2 activating mutant F604P by cryo-electron microscopy reveals a π- to α-helix transition within the pore-lining helix S6 that leads to repositioning of the gate residue and channel activation. Overall the results identify hydrophobic gates and a gating mechanism of PKD2 and PKD2L1. Mutations in the cation channel PKD2 cause human autosomal dominant polycystic kidney disease but its channel function and gating mechanism are poorly understood. Here authors study PKD2 using electrophysiology and cryo-EM, which identifies hydrophobic gates and proposes a gating mechanism for PKD2.
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Affiliation(s)
- Wang Zheng
- National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, Hubei, 430068, China.,Department of Physiology, Membrane Protein Disease Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - Xiaoyong Yang
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, 84112, USA
| | - Ruikun Hu
- School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Ruiqi Cai
- Department of Physiology, Membrane Protein Disease Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - Laura Hofmann
- Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, Homburg, 66421, Germany
| | - Zhifei Wang
- Department of Biological Sciences, St. John's University, Queens, NY, 11439, USA
| | - Qiaolin Hu
- Department of Physiology, Membrane Protein Disease Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - Xiong Liu
- Department of Physiology, Membrane Protein Disease Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - David Bulkley
- Keck Advanced Microscopy Laboratory and Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Yong Yu
- Department of Biological Sciences, St. John's University, Queens, NY, 11439, USA
| | - Jingfeng Tang
- National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, Hubei, 430068, China.
| | - Veit Flockerzi
- Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, Homburg, 66421, Germany
| | - Ying Cao
- School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Erhu Cao
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, 84112, USA.
| | - Xing-Zhen Chen
- National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, Hubei, 430068, China. .,Department of Physiology, Membrane Protein Disease Research Group, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2H7, Canada.
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Structure of the polycystic kidney disease TRP channel Polycystin-2 (PC2). Nat Struct Mol Biol 2016; 24:114-122. [PMID: 27991905 DOI: 10.1038/nsmb.3343] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 11/14/2016] [Indexed: 12/12/2022]
Abstract
Mutations in either polycystin-1 (PC1 or PKD1) or polycystin-2 (PC2, PKD2 or TRPP1) cause autosomal-dominant polycystic kidney disease (ADPKD) through unknown mechanisms. Here we present the structure of human PC2 in a closed conformation, solved by electron cryomicroscopy at 4.2-Å resolution. The structure reveals a novel polycystin-specific 'tetragonal opening for polycystins' (TOP) domain tightly bound to the top of a classic transient receptor potential (TRP) channel structure. The TOP domain is formed from two extensions to the voltage-sensor-like domain (VSLD); it covers the channel's endoplasmic reticulum lumen or extracellular surface and encloses an upper vestibule, above the pore filter, without blocking the ion-conduction pathway. The TOP-domain fold is conserved among the polycystins, including the homologous channel-like region of PC1, and is the site of a cluster of ADPKD-associated missense variants. Extensive contacts among the TOP-domain subunits, the pore and the VSLD provide ample scope for regulation through physical and chemical stimuli.
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Yang Y, Ehrlich BE. Structural studies of the C-terminal tail of polycystin-2 (PC2) reveal insights into the mechanisms used for the functional regulation of PC2. J Physiol 2016; 594:4141-9. [PMID: 26857659 DOI: 10.1113/jp270933] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/21/2016] [Indexed: 01/17/2023] Open
Abstract
Mutations in polycystin-2 (PC2) lead to autosomal dominant polycystic kidney disease (ADPKD). The molecular mechanism linking mutations in PC2 and the pathogenesis of ADPKD is not well understood. Therefore, understanding the functional regulation of PC2 and its interaction with other proteins under both physiological and pathogenic conditions is important for elucidating the disease mechanism and identifying potential molecular targets for treatment. Normally, PC2 functions as a calcium-permeable channel whose activity is regulated by calcium binding to the C-terminal domain of PC2 (PC2 Cterm). The PC2 Cterm is also involved in the PC2 channel assembly and hetero-oligomerization with other binding partners in cells. Different functional domains of the PC2 Cterm have been studied using structural approaches. Within the PC2 Cterm, there is a calcium-binding EF-hand domain, crucial for the calcium-dependent activity of the PC2 channel. Downstream of the EF-hand domain lies a coiled-coil region, which is involved in the assembly and hetero-interaction of the PC2 protein. The PC2 Cterm can form an oligomer, mediated by the coiled-coil region. Although PC2 Cterm has been extensively studied for its relationship with ADPKD and its importance in PC2 regulation, there are misunderstandings with respect to the definition of the domain topology within the PC2 Cterm and the functional role of each domain. Here, we review previous studies that connect the molecular properties of the domains of PC2 Cterm to distinct aspects of PC2 functions and regulation.
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Affiliation(s)
- Yifei Yang
- Department of Laboratory Medicine, Yale University, New Haven, CT, 06520, USA.,Department of Pharmacology, Yale University, New Haven, CT, 06520, USA
| | - Barbara E Ehrlich
- Department of Pharmacology, Yale University, New Haven, CT, 06520, USA.,Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, 06520, USA
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Function and regulation of TRPP2 ion channel revealed by a gain-of-function mutant. Proc Natl Acad Sci U S A 2016; 113:E2363-72. [PMID: 27071085 DOI: 10.1073/pnas.1517066113] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Mutations in polycystin-1 and transient receptor potential polycystin 2 (TRPP2) account for almost all clinically identified cases of autosomal dominant polycystic kidney disease (ADPKD), one of the most common human genetic diseases. TRPP2 functions as a cation channel in its homomeric complex and in the TRPP2/polycystin-1 receptor/ion channel complex. The activation mechanism of TRPP2 is unknown, which significantly limits the study of its function and regulation. Here, we generated a constitutively active gain-of-function (GOF) mutant of TRPP2 by applying a mutagenesis scan on the S4-S5 linker and the S5 transmembrane domain, and studied functional properties of the GOF TRPP2 channel. We found that extracellular divalent ions, including Ca(2+), inhibit the permeation of monovalent ions by directly blocking the TRPP2 channel pore. We also found that D643, a negatively charged amino acid in the pore, is crucial for channel permeability. By introducing single-point ADPKD pathogenic mutations into the GOF TRPP2, we showed that different mutations could have completely different effects on channel activity. The in vivo function of the GOF TRPP2 was investigated in zebrafish embryos. The results indicate that, compared with wild type (WT), GOF TRPP2 more efficiently rescued morphological abnormalities, including curly tail and cyst formation in the pronephric kidney, caused by down-regulation of endogenous TRPP2 expression. Thus, we established a GOF TRPP2 channel that can serve as a powerful tool for studying the function and regulation of TRPP2. The GOF channel may also have potential application for developing new therapeutic strategies for ADPKD.
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15
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Conformational dynamics of Ca2+-dependent responses in the polycystin-2 C-terminal tail. Biochem J 2016; 473:285-96. [DOI: 10.1042/bj20151031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 11/16/2015] [Indexed: 01/13/2023]
Abstract
The C-terminal tail of polycystin-2 is crucial for channel regulation and contains a Ca2+-binding EF-hand domain and a coiled-coil domain. The C-terminal tail and isolated EF-hand share similar Ca2+-binding affinities; however, their dynamic responses to Ca2+ are different.
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Yang Y, Keeler C, Kuo IY, Lolis EJ, Ehrlich BE, Hodsdon ME. Oligomerization of the polycystin-2 C-terminal tail and effects on its Ca2+-binding properties. J Biol Chem 2015; 290:10544-54. [PMID: 25716316 PMCID: PMC4400361 DOI: 10.1074/jbc.m115.641803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Indexed: 02/05/2023] Open
Abstract
Polycystin-2 (PC2) belongs to the transient receptor potential (TRP) family and forms a Ca2+-regulated channel. The C-terminal cytoplasmic tail of human PC2 (HPC2 Cterm) is important for PC2 channel assembly and regulation. In this study, we characterized the oligomeric states and Ca2+-binding profiles in the C-terminal tail using biophysical approaches. Specifically, we determined that HPC2 Cterm forms a trimer in solution with and without Ca2+ bound, although TRP channels are believed to be tetramers. We found that there is only one Ca2+-binding site in the HPC2 Cterm, located within its EF-hand domain. However, the Ca2+ binding affinity of the HPC2 Cterm trimer is greatly enhanced relative to the intrinsic binding affinity of the isolated EF-hand domain. We also employed the sea urchin PC2 (SUPC2) as a model for biophysical and structural characterization. The sea urchin C-terminal construct (SUPC2 Ccore) also forms trimers in solution, independent of Ca2+ binding. In contrast to the human PC2, the SUPC2 Ccore contains two cooperative Ca2+-binding sites within its EF-hand domain. Consequently, trimerization does not further improve the affinity of Ca2+ binding in the SUPC2 Ccore relative to the isolated EF-hand domain. Using NMR, we localized the Ca2+-binding sites in the SUPC2 Ccore and characterized the conformational changes in its EF-hand domain due to trimer formation. Our study provides a structural basis for understanding the Ca2+-dependent regulation of the PC2 channel by its cytosolic C-terminal domain. The improved methodology also serves as a good strategy to characterize other Ca2+-binding proteins.
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Affiliation(s)
- Yifei Yang
- From the Departments of Laboratory Medicine, Pharmacology, and
| | | | | | | | - Barbara E Ehrlich
- Pharmacology, and Cellular and Molecular Physiology, School of Medicine, Yale University, New Haven, Connecticut 06520
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Abstract
Mutations in polycystin 1 and 2 (PC1 and PC2) cause the common genetic kidney disorder autosomal dominant polycystic kidney disease (ADPKD). It is unknown how these mutations result in renal cysts, but dysregulation of calcium (Ca(2+)) signaling is a known consequence of PC2 mutations. PC2 functions as a Ca(2+)-activated Ca(2+) channel of the endoplasmic reticulum. We hypothesize that Ca(2+) signaling through PC2, or other intracellular Ca(2+) channels such as the inositol 1,4,5-trisphosphate receptor (InsP3R), is necessary to maintain renal epithelial cell function and that disruption of the Ca(2+) signaling leads to renal cyst development. The cell line LLC-PK1 has traditionally been used for studying PKD-causing mutations and Ca(2+) signaling in 2D culture systems. We demonstrate that this cell line can be used in long-term (8 wk) 3D tissue culture systems. In 2D systems, knockdown of InsP3R results in decreased Ca(2+) transient signals that are rescued by overexpression of PC2. In 3D systems, knockdown of either PC2 or InsP3R leads to cyst formation, but knockdown of InsP3R type 1 (InsP3R1) generated the largest cysts. InsP3R1 and InsP3R3 are differentially localized in both mouse and human kidney, suggesting that regional disruption of Ca(2+) signaling contributes to cystogenesis. All cysts had intact cilia 2 wk after starting 3D culture, but the cells with InsP3R1 knockdown lost cilia as the cysts grew. Studies combining 2D and 3D cell culture systems will assist in understanding how mutations in PC2 that confer altered Ca(2+) signaling lead to ADPKD cysts.
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