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Avila H, Truong A, Tyrpak D, Lee SJ, Lei S, Li Y, Okamoto C, Hamm-Alvarez S, MacKay JA. Intracellular Dynamin Elastin-like Polypeptides Assemble into Rodlike, Spherical, and Reticular Dynasomes. Biomacromolecules 2022; 23:265-275. [PMID: 34914359 PMCID: PMC9159747 DOI: 10.1021/acs.biomac.1c01251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Dynamin (DNM) is a family of large GTPases possessing a unique mechanical ability to "pinch" off vesicles entering cells. DNM2 is the most ubiquitously expressed member of the DNM family. We developed a novel tool based on elastin-like polypeptide (ELP) technology to quickly, precisely, and reversibly modulate the structure of DNM2. ELPs are temperature-sensitive biopolymers that self-assemble into microdomains above sharp transition temperatures. When linked together, DNM2 and a temperature-sensitive ELP fusion organize into a range of distinct temperature-dependent structures above a sharp transition temperature, which were not observed with wild-type DNM2 or a temperature-insensitive ELP fusion control. The structures comprised three different morphologies, which were prevalent at different temperature ranges. The size of these structures was influenced by an inhibitor of the DNM2 GTPase activity, dynasore; furthermore, they appear to entrap co-expressed cytosolic ELPs. Having demonstrated an unexpected diversity of morphologically distinct structures, DNM2-ELP fusions may have applications in the exploration of dynamin-dependent biology.
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Affiliation(s)
- Hugo Avila
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - Anh Truong
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - David Tyrpak
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - Shin-Jae Lee
- USC Viterbi School of Engineering, Department of Biomedical Engineering, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - Siqi Lei
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - Yaocun Li
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - Curtis Okamoto
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - Sarah Hamm-Alvarez
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089,USC Keck School of Medicine, Department of Ophthalmology, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
| | - J. Andrew MacKay
- USC School of Pharmacy, Department of Pharmacology and Pharmaceutical Sciences, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089,USC Viterbi School of Engineering, Department of Biomedical Engineering, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089,USC Keck School of Medicine, Department of Ophthalmology, University of Southern California School of Pharmacy, 1985 Zonal Ave., PSC 306A, Los Angeles, CA, 90089
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ESCRTs cut some slack. Nat Cell Biol 2020; 22:915-916. [PMID: 32753668 DOI: 10.1038/s41556-020-0557-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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3
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Dragwidge JM, Scholl S, Schumacher K, Gendall AR. NHX-type Na+(K+)/H+ antiporters are required for TGN/EE trafficking and endosomal ion homeostasis in Arabidopsis. J Cell Sci 2019; 132:jcs.226472. [DOI: 10.1242/jcs.226472] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 02/21/2019] [Indexed: 12/17/2022] Open
Abstract
The regulation of ion and pH homeostasis of endomembrane organelles is critical for functional protein trafficking, sorting and modification in eukaryotic cells. pH homeostasis is maintained through the activity of vacuolar H+-ATPases (V-ATPases) pumping protons (H+) into the endomembrane lumen, and counter-action by cation/proton exchangers such as the NHX family of Na+(K+)/H+ exchangers. In plants, V-ATPase activity at the trans-Golgi network/early endosome (TGN/EE) is important for secretory and endocytic trafficking, however the role of the endosomal antiporters NHX5 and NHX6 in endomembrane trafficking is unclear. Here we show through genetic, pharmacological, and live-cell imaging approaches that double knockout of NHX5 and NHX6 results in the impairment of endosome motility, protein recycling at the TGN/EE, but not in the secretion of integral membrane proteins. Furthermore, we report that nhx5 nhx6 mutants are partially insensitive to osmotic swelling of TGN/EE induced by the monovalent cation ionophore monensin, and to late endosomal swelling by the phosphatidylinositol 3/4-kinase inhibitor wortmannin, demonstrating that NHX5 and NHX6 function to regulate the luminal cation composition of endosomes.
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Affiliation(s)
- Jonathan Michael Dragwidge
- Department of Animal, Plant and Soil Sciences, AgriBio, Centre for AgriBiosciences, 5 Ring Road, La Trobe University, Bundoora, VIC 3086, Australia
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Stefan Scholl
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Karin Schumacher
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Anthony Richard Gendall
- Department of Animal, Plant and Soil Sciences, AgriBio, Centre for AgriBiosciences, 5 Ring Road, La Trobe University, Bundoora, VIC 3086, Australia
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Karim MA, Brett CL. The Na +(K +)/H + exchanger Nhx1 controls multivesicular body-vacuolar lysosome fusion. Mol Biol Cell 2018; 29:317-325. [PMID: 29212874 PMCID: PMC5996954 DOI: 10.1091/mbc.e17-08-0496] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 11/07/2017] [Accepted: 11/28/2017] [Indexed: 01/12/2023] Open
Abstract
Loss-of-function mutations in human endosomal Na+(K+)/H+ exchangers (NHEs) NHE6 and NHE9 are implicated in neurological disorders including Christianson syndrome, autism, and attention deficit and hyperactivity disorder. These mutations disrupt retention of surface receptors within neurons and glial cells by affecting their delivery to lysosomes for degradation. However, the molecular basis of how these endosomal NHEs control endocytic trafficking is unclear. Using Saccharomyces cerevisiae as a model, we conducted cell-free organelle fusion assays to show that transport activity of the orthologous endosomal NHE Nhx1 is important for multivesicular body (MVB)-vacuolar lysosome fusion, the last step of endocytosis required for surface protein degradation. We find that deleting Nhx1 disrupts the fusogenicity of the MVB, not the vacuole, by targeting pH-sensitive machinery downstream of the Rab-GTPase Ypt7 needed for SNARE-mediated lipid bilayer merger. All contributing mechanisms are evolutionarily conserved offering new insight into the etiology of human disorders linked to loss of endosomal NHE function.
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TOR Complex 2-Regulated Protein Kinase Fpk1 Stimulates Endocytosis via Inhibition of Ark1/Prk1-Related Protein Kinase Akl1 in Saccharomyces cerevisiae. Mol Cell Biol 2017; 37:MCB.00627-16. [PMID: 28069741 PMCID: PMC5359421 DOI: 10.1128/mcb.00627-16] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 01/03/2017] [Indexed: 12/23/2022] Open
Abstract
Depending on the stress, plasma membrane alterations activate or inhibit yeast target of rapamycin (TOR) complex 2, which, in turn, upregulates or downregulates the activity of its essential downstream effector, protein kinase Ypk1. Through phosphorylation of multiple substrates, Ypk1 controls many processes that restore homeostasis. One such substrate is protein kinase Fpk1, which is negatively regulated by Ypk1. Fpk1 phosphorylates and stimulates flippases that translocate aminoglycerophospholipids from the outer to the inner leaflet of the plasma membrane. Fpk1 has additional roles, but other substrates were uncharacterized. We show that Fpk1 phosphorylates and inhibits protein kinase Akl1, related to protein kinases Ark1 and Prk1, which modulate the dynamics of actin patch-mediated endocytosis. Akl1 has two Fpk1 phosphorylation sites (Ark1 and Prk1 have none) and is hypophosphorylated when Fpk1 is absent. Conversely, under conditions that inactivate TORC2-Ypk1 signaling, which alleviates Fpk1 inhibition, Akl1 is hyperphosphorylated. Monitoring phosphorylation of known Akl1 substrates (Sla1 and Ent2) confirmed that Akl1 is hyperactive when not phosphorylated by Fpk1. Fpk1-mediated negative regulation of Akl1 enhances endocytosis, because an Akl1 mutant immune to Fpk1 phosphorylation causes faster dissociation of Sla1 from actin patches, confers elevated resistance to doxorubicin (a toxic compound whose entry requires endocytosis), and impedes Lucifer yellow uptake (a marker of fluid phase endocytosis). Thus, TORC2-Ypk1, by regulating Fpk1-mediated phosphorylation of Akl1, adjusts the rate of endocytosis.
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Yenush L. Potassium and Sodium Transport in Yeast. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 892:187-228. [DOI: 10.1007/978-3-319-25304-6_8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Sodium-Proton (Na+/H+) Antiporters: Properties and Roles in Health and Disease. Met Ions Life Sci 2016; 16:391-458. [DOI: 10.1007/978-3-319-21756-7_12] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Li Z, Blissard G. The vacuolar protein sorting genes in insects: A comparative genome view. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2015; 62:211-225. [PMID: 25486452 DOI: 10.1016/j.ibmb.2014.11.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 11/06/2014] [Accepted: 11/21/2014] [Indexed: 06/04/2023]
Abstract
In eukaryotic cells, regulated vesicular trafficking is critical for directing protein transport and for recycling and degradation of membrane lipids and proteins. Through carefully regulated transport vesicles, the endomembrane system performs a large and important array of dynamic cellular functions while maintaining the integrity of the cellular membrane system. Genetic studies in yeast Saccharomyces cerevisiae have identified approximately 50 vacuolar protein sorting (VPS) genes involved in vesicle trafficking, and most of these genes are also characterized in mammals. The VPS proteins form distinct functional complexes, which include complexes known as ESCRT, retromer, CORVET, HOPS, GARP, and PI3K-III. Little is known about the orthologs of VPS proteins in insects. Here, with the newly annotated Manduca sexta genome, we carried out genomic comparative analysis of VPS proteins in yeast, humans, and 13 sequenced insect genomes representing the Orders Hymenoptera, Diptera, Hemiptera, Phthiraptera, Lepidoptera, and Coleoptera. Amino acid sequence alignments and domain/motif structure analyses reveal that most of the components of ESCRT, retromer, CORVET, HOPS, GARP, and PI3K-III are evolutionarily conserved across yeast, insects, and humans. However, in contrast to the VPS gene expansions observed in the human genome, only four VPS genes (VPS13, VPS16, VPS33, and VPS37) were expanded in the six insect Orders. Additionally, VPS2 was expanded only in species from Phthiraptera, Lepidoptera, and Coleoptera. These studies provide a baseline for understanding the evolution of vesicular trafficking across yeast, insect, and human genomes, and also provide a basis for further addressing specific functional roles of VPS proteins in insects.
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Affiliation(s)
- Zhaofei Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, Key Laboratory of Northwest Loess Plateau Crop Pest Management of Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Taicheng Road, Yangling, Shaanxi 712100, China.
| | - Gary Blissard
- Boyce Thompson Institute, Cornell University, Ithaca, NY 14853, USA
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Papouskova K, Jiang L, Sychrova H. Vcx1 and ESCRT components regulate intracellular pH homeostasis in the response of yeast cells to calcium stress. FEMS Yeast Res 2015; 15:fov007. [PMID: 25690770 DOI: 10.1093/femsyr/fov007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Endosomal sorting complexes required for transport (ESCRTs) are involved in the formation of multivesicular bodies and sorting of targeted proteins to the yeast vacuole. The deletion of seven genes encoding components of the ESCRT machinery render Saccharomyces cerevisiae cells sensitive to high extracellular CaCl2 concentrations as well as to low pH in media. In this work, we focused on intracellular pH (pHin) homeostasis of these mutants. None of the studied ESCRT mutants exhibited an altered pHin level compared to the wild type under standard growth conditions. Nevertheless, 60 min of CaCl2 treatment resulted in a more significant drop in pHin levels in these mutants than in the wild type, suggesting that pHin homeostasis is affected in ESCRT mutants upon the addition of calcium. Similarly, CaCl2 treatment caused a bigger pHin decrease in cells lacking the vacuolar Ca(2+)/H(+) antiporter Vcx1 which indicates a role for this protein in the maintenance of proper pHin homeostasis when cells need to cope with a high CaCl2 concentration in media. Importantly, ESCRT gene deletions in the vcx1Δ strain did not result in an increase in the CaCl2-invoked drop in the pHin levels of cells, which demonstrates a genetic interaction between VCX1 and studied ESCRT genes.
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Affiliation(s)
- Klara Papouskova
- Department of Membrane Transport, Institute of Physiology Academy of Sciences of the Czech Republic, v.v.i., Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Linghuo Jiang
- The National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, China The State Key Laboratory of Food Science and Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Hana Sychrova
- Department of Membrane Transport, Institute of Physiology Academy of Sciences of the Czech Republic, v.v.i., Videnska 1083, 142 20 Prague 4, Czech Republic
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Kondapalli KC, Prasad H, Rao R. An inside job: how endosomal Na(+)/H(+) exchangers link to autism and neurological disease. Front Cell Neurosci 2014; 8:172. [PMID: 25002837 PMCID: PMC4066934 DOI: 10.3389/fncel.2014.00172] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 06/04/2014] [Indexed: 12/02/2022] Open
Abstract
Autism imposes a major impediment to childhood development and a huge emotional and financial burden on society. In recent years, there has been rapidly accumulating genetic evidence that links the eNHE, a subset of Na(+)/H(+) exchangers that localize to intracellular vesicles, to a variety of neurological conditions including autism, attention deficit hyperactivity disorder (ADHD), intellectual disability, and epilepsy. By providing a leak pathway for protons pumped by the V-ATPase, eNHE determine luminal pH and regulate cation (Na(+), K(+)) content in early and recycling endosomal compartments. Loss-of-function mutations in eNHE cause hyperacidification of endosomal lumen, as a result of imbalance in pump and leak pathways. Two isoforms, NHE6 and NHE9 are highly expressed in brain, including hippocampus and cortex. Here, we summarize evidence for the importance of luminal cation content and pH on processing, delivery and fate of cargo. Drawing upon insights from model organisms and mammalian cells we show how eNHE affect surface expression and function of membrane receptors and neurotransmitter transporters. These studies lead to cellular models of eNHE activity in pre- and post-synaptic neurons and astrocytes, where they could impact synapse development and plasticity. The study of eNHE has provided new insight on the mechanism of autism and other debilitating neurological disorders and opened up new possibilities for therapeutic intervention.
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Affiliation(s)
| | | | - Rajini Rao
- Department of Physiology, The Johns Hopkins University School of MedicineBaltimore, MD, USA
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Montefusco DJ, Matmati N, Hannun YA. The yeast sphingolipid signaling landscape. Chem Phys Lipids 2014; 177:26-40. [PMID: 24220500 PMCID: PMC4211598 DOI: 10.1016/j.chemphyslip.2013.10.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 10/18/2013] [Accepted: 10/19/2013] [Indexed: 12/13/2022]
Abstract
Sphingolipids are recognized as signaling mediators in a growing number of pathways, and represent potential targets to address many diseases. The study of sphingolipid signaling in yeast has created a number of breakthroughs in the field, and has the potential to lead future advances. The aim of this article is to provide an inclusive view of two major frontiers in yeast sphingolipid signaling. In the first section, several key studies in the field of sphingolipidomics are consolidated to create a yeast sphingolipidome that ranks nearly all known sphingolipid species by their level in a resting yeast cell. The second section presents an overview of most known phenotypes identified for sphingolipid gene mutants, presented with the intention of illuminating not yet discovered connections outside and inside of the field.
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Affiliation(s)
- David J Montefusco
- Dept. Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, United States.
| | - Nabil Matmati
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, United States
| | - Yusuf A Hannun
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, United States.
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Donowitz M, Ming Tse C, Fuster D. SLC9/NHE gene family, a plasma membrane and organellar family of Na⁺/H⁺ exchangers. Mol Aspects Med 2013; 34:236-51. [PMID: 23506868 DOI: 10.1016/j.mam.2012.05.001] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 03/09/2012] [Indexed: 12/24/2022]
Abstract
This brief review of the human Na/H exchanger gene family introduces a new classification with three subgroups to the SLC9 gene family. Progress in the structure and function of this gene family is reviewed with structure based on homology to the bacterial Na/H exchanger NhaA. Human diseases which result from genetic abnormalities of the SLC9 family are discussed although the exact role of these transporters in causing any disease is not established, other than poorly functioning NHE3 in congenital Na diarrhea.
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Affiliation(s)
- Mark Donowitz
- Departments of Medicine and Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
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Mulet JM, Llopis-Torregrosa V, Primo C, Marqués MC, Yenush L. Endocytic regulation of alkali metal transport proteins in mammals, yeast and plants. Curr Genet 2013; 59:207-30. [PMID: 23974285 DOI: 10.1007/s00294-013-0401-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 07/24/2013] [Accepted: 07/29/2013] [Indexed: 12/30/2022]
Abstract
The relative concentrations of ions and solutes inside cells are actively maintained by several classes of transport proteins, in many cases against their concentration gradient. These transport processes, which consume a large portion of cellular energy, must be constantly regulated. Many structurally distinct families of channels, carriers, and pumps have been characterized in considerable detail during the past decades and defects in the function of some of these proteins have been linked to a growing list of human diseases. The dynamic regulation of the transport proteins present at the cell surface is vital for both normal cellular function and for the successful adaptation to changing environments. The composition of proteins present at the cell surface is controlled on both the transcriptional and post-translational level. Post-translational regulation involves highly conserved mechanisms of phosphorylation- and ubiquitylation-dependent signal transduction routes used to modify the cohort of receptors and transport proteins present under any given circumstances. In this review, we will summarize what is currently known about one facet of this regulatory process: the endocytic regulation of alkali metal transport proteins. The physiological relevance, major contributors, parallels and missing pieces of the puzzle in mammals, yeast and plants will be discussed.
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Affiliation(s)
- José Miguel Mulet
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avd. de los Naranjos s/n, 46022, Valencia, Spain
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Abstract
All living organisms require nutrient minerals for growth and have developed mechanisms to acquire, utilize, and store nutrient minerals effectively. In the aqueous cellular environment, these elements exist as charged ions that, together with protons and hydroxide ions, facilitate biochemical reactions and establish the electrochemical gradients across membranes that drive cellular processes such as transport and ATP synthesis. Metal ions serve as essential enzyme cofactors and perform both structural and signaling roles within cells. However, because these ions can also be toxic, cells have developed sophisticated homeostatic mechanisms to regulate their levels and avoid toxicity. Studies in Saccharomyces cerevisiae have characterized many of the gene products and processes responsible for acquiring, utilizing, storing, and regulating levels of these ions. Findings in this model organism have often allowed the corresponding machinery in humans to be identified and have provided insights into diseases that result from defects in ion homeostasis. This review summarizes our current understanding of how cation balance is achieved and modulated in baker's yeast. Control of intracellular pH is discussed, as well as uptake, storage, and efflux mechanisms for the alkali metal cations, Na(+) and K(+), the divalent cations, Ca(2+) and Mg(2+), and the trace metal ions, Fe(2+), Zn(2+), Cu(2+), and Mn(2+). Signal transduction pathways that are regulated by pH and Ca(2+) are reviewed, as well as the mechanisms that allow cells to maintain appropriate intracellular cation concentrations when challenged by extreme conditions, i.e., either limited availability or toxic levels in the environment.
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Qiu QS. V-ATPase, ScNhx1p and Yeast Vacuole Fusion. J Genet Genomics 2012; 39:167-71. [DOI: 10.1016/j.jgg.2012.02.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 02/02/2012] [Accepted: 02/02/2012] [Indexed: 01/07/2023]
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