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Azevedo C, Borghi F, Su XB, Saiardi A. On the covalent nature of lysine polyphosphorylation. Mol Cell 2024; 84:1811-1815.e3. [PMID: 38701742 DOI: 10.1016/j.molcel.2024.03.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 03/22/2024] [Accepted: 03/29/2024] [Indexed: 05/05/2024]
Abstract
Post-translational modifications of proteins (PTMs) introduce an extra layer of complexity to cellular regulation. Although phosphorylation of serine, threonine, and tyrosine residues is well-known as PTMs, lysine is, in fact, the most heavily modified amino acid, with over 30 types of PTMs on lysine having been characterized. One of the most recently discovered PTMs on lysine residues is polyphosphorylation, which sees linear chains of inorganic polyphosphates (polyP) attached to lysine residues. The labile nature of phosphoramidate bonds raises the question of whether this modification is covalent in nature. Here, we used buffers with very high ionic strength, which would disrupt any non-covalent interactions, and confirmed that lysine polyphosphorylation occurs covalently on proteins containing PASK domains (polyacidic, serine-, and lysine-rich), such as the budding yeast protein nuclear signal recognition 1 (Nsr1) and the mammalian protein nucleolin. This Matters Arising Response paper addresses the Neville et al. (2024) Matters Arising paper, published concurrently in Molecular Cell.
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Affiliation(s)
- Cristina Azevedo
- Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; InnovPlantProtect, Estrada Gil Vaz, 7350-478 Elvas, Portugal
| | - Filipy Borghi
- Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Xue Bessie Su
- Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Adolfo Saiardi
- Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK.
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2
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Chelebieva ES, Kladchenko ES, Mindukshev IV, Gambaryan S, Andreyeva AY. ROS formation, mitochondrial potential and osmotic stability of the lamprey red blood cells: effect of adrenergic stimulation and hypoosmotic stress. FISH PHYSIOLOGY AND BIOCHEMISTRY 2024:10.1007/s10695-024-01342-5. [PMID: 38647979 DOI: 10.1007/s10695-024-01342-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 03/27/2024] [Indexed: 04/25/2024]
Abstract
Semi-anadromous animals experience salinity fluctuations during their life-span period. Alterations of environmental conditions induce stress response where catecholamines (CA) play a central role. Physiological stress and changes in external and internal osmolarity are frequently associated with increased production of reactive oxygen species (ROS). In this work, we studied the involvement of the cAMP/PKA pathway in mediating catecholamine-dependent effects on osmoregulatory responses, intracellular production of ROS, and mitochondrial membrane potential of the river lamprey (Lampetra fluviatilis, Linnaeus, 1758) red blood cells (RBCs). We also investigated the role of hypoosmotic shock in the process of ROS production and mitochondrial respiration of RBCs. For this, osmotic stability and the dynamics of the regulatory volume decrease (RVD) following hypoosmotic swelling, intracellular ROS levels, and changes in mitochondrial membrane potential were assessed in RBCs treated with epinephrine (Epi, 25 μM) and forskolin (Forsk, 20 μM). Epi and Forsk markedly reduced the osmotic stability of the lamprey RBCs whereas did not affect the dynamics of the RVD response in a hypoosmotic environment. Activation of PKA with Epi and Forsk increased ROS levels and decreased mitochondrial membrane potential of the lamprey RBCs. In contrast, upon hypoosmotic shock enhanced ROS production in RBCs was accompanied by increased mitochondrial membrane potential. Overall, a decrease in RBC osmotic stability and the enhancement of ROS formation induced by β-adrenergic stimulation raises concerns about stress-associated changes in RBC functions in agnathans. Increased ROS production in RBCs under hypoosmotic shock indicates that a decrease in blood osmolarity may be associated with oxidative damage of RBCs during lamprey migration.
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Affiliation(s)
- Elina S Chelebieva
- Laboratory of Ecological Immunology of Aquatic Organisms, Moscow Representative Office A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Leninsky Ave 38, Moscow, Russia, 119991
| | - Ekaterina S Kladchenko
- Laboratory of Ecological Immunology of Aquatic Organisms, Moscow Representative Office A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Leninsky Ave 38, Moscow, Russia, 119991.
| | - Igor V Mindukshev
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Toreza, 44, St-Petersburg, Russia, 194223
| | - Stepan Gambaryan
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Toreza, 44, St-Petersburg, Russia, 194223
| | - Alexandra Yu Andreyeva
- Laboratory of Ecological Immunology of Aquatic Organisms, Moscow Representative Office A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Leninsky Ave 38, Moscow, Russia, 119991
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Toreza, 44, St-Petersburg, Russia, 194223
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3
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Mao W, Renner LD, Cornilleau C, Li de la Sierra-Gallay I, Afensiss S, Benlamara S, Ah-Seng Y, Van Tilbeurgh H, Nessler S, Bertin A, Chastanet A, Carballido-Lopez R. On the role of nucleotides and lipids in the polymerization of the actin homolog MreB from a Gram-positive bacterium. eLife 2023; 12:e84505. [PMID: 37818717 PMCID: PMC10718530 DOI: 10.7554/elife.84505] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 10/08/2023] [Indexed: 10/12/2023] Open
Abstract
In vivo, bacterial actin MreB assembles into dynamic membrane-associated filamentous structures that exhibit circumferential motion around the cell. Current knowledge of MreB biochemical and polymerization properties in vitro remains limited and is mostly based on MreB proteins from Gram-negative species. In this study, we report the first observation of organized protofilaments by electron microscopy and the first 3D-structure of MreB from a Gram-positive bacterium. We show that Geobacillus stearothermophilus MreB forms straight pairs of protofilaments on lipid surfaces in the presence of ATP or GTP, but not in the presence of ADP, GDP or non-hydrolysable ATP analogs. We demonstrate that membrane anchoring is mediated by two spatially close short hydrophobic sequences while electrostatic interactions also contribute to lipid binding, and show that the population of membrane-bound protofilament doublets is in steady-state. In solution, protofilament doublets were not detected in any condition tested. Instead, MreB formed large sheets regardless of the bound nucleotide, albeit at a higher critical concentration. Altogether, our results indicate that both lipids and ATP are facilitators of MreB polymerization, and are consistent with a dual effect of ATP hydrolysis, in promoting both membrane binding and filaments assembly/disassembly.
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Affiliation(s)
- Wei Mao
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis InstituteJouy-en-JosasFrance
| | - Lars D Renner
- Leibniz Institute of Polymer Research, and the Max-Bergmann-Center of BiomaterialsDresdenGermany
| | - Charlène Cornilleau
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis InstituteJouy-en-JosasFrance
| | - Ines Li de la Sierra-Gallay
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRSGif-sur-YvetteFrance
| | - Sana Afensiss
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis InstituteJouy-en-JosasFrance
| | - Sarah Benlamara
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis InstituteJouy-en-JosasFrance
| | - Yoan Ah-Seng
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis InstituteJouy-en-JosasFrance
| | - Herman Van Tilbeurgh
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRSGif-sur-YvetteFrance
| | - Sylvie Nessler
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRSGif-sur-YvetteFrance
| | - Aurélie Bertin
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, Sorbonne Université, 75005ParisFrance
| | - Arnaud Chastanet
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis InstituteJouy-en-JosasFrance
| | - Rut Carballido-Lopez
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis InstituteJouy-en-JosasFrance
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4
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Rioux KL, Delaney S. Ionic strength modulates excision of uracil by SMUG1 from nucleosome core particles. DNA Repair (Amst) 2023; 125:103482. [PMID: 36931160 PMCID: PMC10073303 DOI: 10.1016/j.dnarep.2023.103482] [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: 12/20/2022] [Revised: 03/04/2023] [Accepted: 03/07/2023] [Indexed: 03/14/2023]
Abstract
Ionic strength affects many cellular processes including the packaging of genetic material in eukaryotes. For example, chromatin fibers are compacted in high ionic strength environments as are the minimal unit of packaging in chromatin, nucleosome core particles (NCPs). Furthermore, ionic strength is known to modulate several aspects of NCP dynamics including transient unwrapping of DNA from the histone protein core, nucleosome gaping, and intra- and internucleosomal interactions of the N-terminal histone tails. Changes in NCP structure may also impact interactions of transcriptional, repair, and other cellular machinery with nucleosomal DNA. One repair process, base excision repair (BER), is impacted by NCP structure and may be further influenced by changes in ionic strength. Here we examine the effects of ionic strength on the initiation of BER using biochemical assays. Using a population of NCPs containing uracil (U) at dozens of geometric locations, excision of U by single-strand selective monofunctional uracil DNA glycosylase (SMUG1) is assessed at higher and lower ionic strengths. SMUG1 has increased excision activity in the lower ionic strength conditions. On duplex DNA, however, SMUG1 activity is largely unaffected by ionic strength except at short incubation times, suggesting that changes in SMUG1 activity are likely due to alterations in NCP structure and dynamics. These results allow us to further understand the cellular role of SMUG1 in a changing ionic environment and broadly contribute to the understanding of BER on chromatin and genomic stability.
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Affiliation(s)
- Katelyn L Rioux
- Department of Chemistry, Brown University, Providence, RI, USA
| | - Sarah Delaney
- Department of Chemistry, Brown University, Providence, RI, USA.
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5
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Landajuela A, Braun M, Martínez-Calvo A, Rodrigues CDA, Gomis Perez C, Doan T, Rudner DZ, Wingreen NS, Karatekin E. Membrane fission during bacterial spore development requires cellular inflation driven by DNA translocation. Curr Biol 2022; 32:4186-4200.e8. [PMID: 36041438 PMCID: PMC9730832 DOI: 10.1016/j.cub.2022.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/26/2022] [Accepted: 08/08/2022] [Indexed: 12/14/2022]
Abstract
Bacteria require membrane fission for both cell division and endospore formation. In Bacillus subtilis, sporulation initiates with an asymmetric division that generates a large mother cell and a smaller forespore that contains only a quarter of its genome. As the mother cell membranes engulf the forespore, a DNA translocase pumps the rest of the chromosome into the small forespore compartment, inflating it due to increased turgor. When the engulfing membrane undergoes fission, the forespore is released into the mother cell cytoplasm. The B. subtilis protein FisB catalyzes membrane fission during sporulation, but the molecular basis is unclear. Here, we show that forespore inflation and FisB accumulation are both required for an efficient membrane fission. Forespore inflation leads to higher membrane tension in the engulfment membrane than in the mother cell membrane, causing the membrane to flow through the neck connecting the two membrane compartments. Thus, the mother cell supplies some of the membrane required for the growth of the membranes surrounding the forespore. The oligomerization of FisB at the membrane neck slows the equilibration of membrane tension by impeding the membrane flow. This leads to a further increase in the tension of the engulfment membrane, promoting its fission through lysis. Collectively, our data indicate that DNA translocation has a previously unappreciated second function in energizing the FisB-mediated membrane fission under energy-limited conditions.
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Affiliation(s)
- Ane Landajuela
- Cellular and Molecular Physiology, Yale University, New Haven, CT, USA; Nanobiology Institute, Yale University, West Haven, CT, USA.
| | - Martha Braun
- Nanobiology Institute, Yale University, West Haven, CT, USA; Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
| | - Alejandro Martínez-Calvo
- Princeton Center for Theoretical Science, Princeton University, Princeton, NJ 08544, USA; Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | | | - Carolina Gomis Perez
- Cellular and Molecular Physiology, Yale University, New Haven, CT, USA; Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Thierry Doan
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires, Aix-Marseille Université-CNRS UMR7255, Marseilles, France
| | - David Z Rudner
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Ned S Wingreen
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Erdem Karatekin
- Cellular and Molecular Physiology, Yale University, New Haven, CT, USA; Nanobiology Institute, Yale University, West Haven, CT, USA; Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA; Université de Paris, Saints-Pères Paris Institute for the Neurosciences (SPPIN), Centre National de la Recherche Scientifique (CNRS), 75006 Paris, France.
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6
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Aplin CP, Miller RC, Kay TM, Heikal AA, Boersma AJ, Sheets ED. Fluorescence depolarization dynamics of ionic strength sensors using time-resolved anisotropy. Biophys J 2021; 120:1417-1430. [PMID: 33582140 DOI: 10.1016/j.bpj.2021.01.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 12/17/2020] [Accepted: 01/20/2021] [Indexed: 10/22/2022] Open
Abstract
Eukaryotic cells exploit dynamic and compartmentalized ionic strength to impact a myriad of biological functions such as enzyme activities, protein-protein interactions, and catalytic functions. Herein, we investigated the fluorescence depolarization dynamics of recently developed ionic strength biosensors (mCerulean3-linker-mCitrine) in Hofmeister salt (KCl, NaCl, NaI, and Na2SO4) solutions. The mCerulean3-mCitrine acts as a Förster resonance energy transfer (FRET) pair, tethered together by two oppositely charged α-helices in the linker region. We developed a time-resolved fluorescence depolarization anisotropy approach for FRET analyses, in which the donor (mCerulean3) is excited by 425-nm laser pulses, followed by fluorescence depolarization analysis of the acceptor (mCitrine) in KE (lysine-glutamate), arginine-aspartate, and arginine-glutamate ionic strength sensors with variable amino acid sequences. Similar experiments were carried out on the cleaved sensors as well as an E6G2 construct, which has neutral α-helices in the linker region, as a control. Our results show distinct dynamics of the intact and cleaved sensors. Importantly, the FRET efficiency decreases and the donor-acceptor distance increases as the environmental ionic strength increases. Our chemical equilibrium analyses of the collapsed-to-stretched conformational state transition of KE reveal that the corresponding equilibrium constant and standard Gibbs free energy changes are ionic strength dependent. We also tested the existing theoretical models for FRET analyses using steady-state anisotropy, which reveal that the angle between the dipole moments of the donor and acceptor in the KE sensor are sensitive to the ionic strength. These results help establish the time-resolved depolarization dynamics of these genetically encoded donor-acceptor pairs as a quantitative means for FRET analysis, which complement traditional methods such as time-resolved fluorescence for future in vivo studies.
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Affiliation(s)
- Cody P Aplin
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, Minnesota
| | - Robert C Miller
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, Minnesota
| | - Taryn M Kay
- Department of Physics and Astronomy, University of Minnesota Duluth, Duluth, Minnesota
| | - Ahmed A Heikal
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, Minnesota.
| | - Arnold J Boersma
- DWI-Leibniz Institute for Interactive Materials, Aachen, Germany.
| | - Erin D Sheets
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, Minnesota.
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7
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Miller RC, Aplin CP, Kay TM, Leighton R, Libal C, Simonet R, Cembran A, Heikal AA, Boersma AJ, Sheets ED. FRET Analysis of Ionic Strength Sensors in the Hofmeister Series of Salt Solutions Using Fluorescence Lifetime Measurements. J Phys Chem B 2020; 124:3447-3458. [PMID: 32267692 DOI: 10.1021/acs.jpcb.9b10498] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Living cells are complex, crowded, and dynamic and continually respond to environmental and intracellular stimuli. They also have heterogeneous ionic strength with compartmentalized variations in both intracellular concentrations and types of ions. These challenges would benefit from the development of quantitative, noninvasive approaches for mapping the heterogeneous ionic strength fluctuations in living cells. Here, we investigated a class of recently developed ionic strength sensors that consists of mCerulean3 (a cyan fluorescent protein) and mCitrine (a yellow fluorescent protein) tethered via a linker made of two charged α-helices and a flexible loop. The two helices are designed to bear opposite charges, which is hypothesized to increase the ionic screening and therefore a larger intermolecular distance. In these protein constructs, mCerulean3 and mCitrine act as a donor-acceptor pair undergoing Förster resonance energy transfer (FRET) that is dependent on both the linker amino acids and the environmental ionic strength. Using time-resolved fluorescence of the donor (mCerulean3), we determined the sensitivity of the energy transfer efficiencies and the donor-acceptor distances of these sensors at variable concentrations of the Hofmeister series of salts (KCl, LiCl, NaCl, NaBr, NaI, Na2SO4). As controls, similar measurements were carried out on the FRET-incapable, enzymatically cleaved counterparts of these sensors as well as a construct designed with two electrostatically neutral α-helices (E6G2). Our results show that the energy transfer efficiencies of these sensors are sensitive to both the linker amino acid sequence and the environmental ionic strength, whereas the sensitivity of these sensors to the identity of the dissolved ions of the Hofmeister series of salts seems limited. We also developed a theoretical framework to explain the observed trends as a function of the ionic strength in terms of the Debye screening of the electrostatic interaction between the two charged α-helices in the linker region. These controlled solution studies represent an important step toward the development of rationally designed FRET-based environmental sensors while offering different models for calculating the energy transfer efficiency using time-resolved fluorescence that is compatible with future in vivo studies.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Arnold J Boersma
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52056 Aachen, Germany
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8
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Abstract
Cell volume homeostasis and its fine-tuning to the specific physiological context at any given moment are processes fundamental to normal cell function. The understanding of cell volume regulation owes much to August Krogh, yet has advanced greatly over the last decades. In this review, we outline the historical context of studies of cell volume regulation, focusing on the lineage started by Krogh, Bodil Schmidt-Nielsen, Hans-Henrik Ussing, and their students. The early work was focused on understanding the functional behaviour, kinetics and thermodynamics of the volume-regulatory ion transport mechanisms. Later work addressed the mechanisms through which cellular signalling pathways regulate the volume regulatory effectors or flux pathways. These studies were facilitated by the molecular identification of most of the relevant channels and transporters, and more recently also by the increased understanding of their structures. Finally, much current research in the field focuses on the most up- and downstream components of these paths: how cells sense changes in cell volume, and how cell volume changes in turn regulate cell function under physiological and pathophysiological conditions.
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Affiliation(s)
- E K Hoffmann
- Section of Cell and Developmental Biology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
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9
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Watanabe T, Inoue K, Takei Y. Identification of angiotensinogen genes with unique and variable angiotensin sequences in chondrichthyans. Gen Comp Endocrinol 2009; 161:115-22. [PMID: 19071126 DOI: 10.1016/j.ygcen.2008.11.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2008] [Revised: 11/06/2008] [Accepted: 11/19/2008] [Indexed: 10/21/2022]
Abstract
The renin-angiotensin system is an enzyme-linked hormonal cascade that plays an important role in body fluid and cardiovascular regulation. The system is initiated by the action of renin on the precursor protein, angiotensinogen (AGT), whose sequence information is scarce because of its high variability among species. In the present study, we cloned AGT in chondrichthyans (elasmobranchs: Triakis scyllium, Dasyatis akajei,Leucoraja erinacea and a holocephalan: Callorhinchus milii). Homology was low among AGTs thus far identified; 25-28% between elasmobranchs and tetrapods and 33-61% even within chondrichthyans. All chondrichthyan angiotensin (ANG) II's have a unique Pro3 instead of Val3 as seen in all other species. In addition, holocephalan ANG II has an unusual His4 instead of Tyr4. In addition, and the N-terminal amino acid, which is usually Asp1 in tetrapods and Asn1 in fishes, was highly variable (Asp, Asn or Tyr) in chondrichthyans. Molecular phylogenetic analysis showed that chondrichthyan AGT precursors are clustered into a group separated from those of tetrapods and teleosts. The AGT gene was most abundantly expressed in the liver, followed by the kidney, interrenal tissue and rectal gland of Triakis where biological actions of ANG II have been demonstrated. Collectively, we identified diversified AGT genes for the first time in chondrichthyes and showed that their ANG II's have unique amino acid residues at positions 1, 3 and 4. High variability of ANG II sequences in chondrichthyans is discussed in relation to their unique regulatory mechanisms such as urea-based osmoregulation.
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Affiliation(s)
- Taro Watanabe
- Laboratory of Physiology, Department of Marine Bioscience, Ocean Research Institute, The University of Tokyo, 1-15-1 Minamidai, Nakano, Tokyo 164-8639, Japan.
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10
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Ernest NJ, Weaver AK, Van Duyn LB, Sontheimer HW. Relative contribution of chloride channels and transporters to regulatory volume decrease in human glioma cells. Am J Physiol Cell Physiol 2005; 288:C1451-60. [PMID: 15659714 PMCID: PMC2548409 DOI: 10.1152/ajpcell.00503.2004] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Primary brain tumors (gliomas) often present with peritumoral edema. Their ability to thrive in this osmotically altered environment prompted us to examine volume regulation in human glioma cells, specifically the relative contribution of Cl(-) channels and transporters to this process. After a hyposmotic challenge, cultured astrocytes, D54-MG glioma cells, and glioma cells from human patient biopsies exhibited a regulatory volume decrease (RVD). Although astrocytes were not able to completely reestablish their original prechallenge volumes, glioma cells exhibited complete volume recovery, sometimes recovering to a volume smaller than their original volumes (V(Post-RVD) < V(baseline)). In glioma cells, RVD was largely inhibited by treatment with a combination of Cl(-) channel inhibitors, 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) and Cd(2+) (V(Post-RVD) > 1.4*V(baseline)). Volume regulation was also attenuated to a lesser degree by the addition of R-(+)-[(2-n-butyl-6,7-dichloro-2-cyclopentyl-2,3-dihydro-1-oxo-1H-inden-5-yl)oxy]acetic acid (DIOA), a known K(+)-Cl(-) cotransporter (KCC) inhibitor. To dissect the relative contribution of channels vs. transporters in RVD, we took advantage of the comparatively high temperature dependence of transport processes vs. channel-mediated diffusion. Cooling D54-MG glioma cells to 15 degrees C resulted in a loss of DIOA-sensitive volume regulation. Moreover, at 15 degrees C, the channel blockers NPPB + Cd(2+) completely inhibited RVD and cells behaved like perfect osmometers. The calculated osmolyte flux during RVD under these experimental conditions suggests that the relative contribution of Cl(-) channels vs. transporters to this process is approximately 60-70% and approximately 30-40%, respectively. Finally, we identified several candidate proteins that may be involved in RVD, including the Cl(-) channels ClC-2, ClC-3, ClC-5, ClC-6, and ClC-7 and the transporters KCC1 and KCC3a.
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Affiliation(s)
- Nola Jean Ernest
- Department of Neurobiology, University of Alabama at Birmingham, USA
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11
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Van der Linden A, Verhoye M, Pörtner HO, Bock C. The strengths of in vivo magnetic resonance imaging (MRI) to study environmental adaptational physiology in fish. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2004; 17:236-48. [PMID: 15614515 DOI: 10.1007/s10334-004-0078-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Revised: 10/18/2004] [Accepted: 10/18/2004] [Indexed: 10/26/2022]
Abstract
Adaptational physiology studies how animals cope with their environment, even if this environment is subject to permanent fluctuations such as tidal or seasonal variations. Aquatic organisms are generally more prone to be exposed to osmotic, hypoxic and temperature challenges than terrestrial animals. Some of these challenges are more restraining in an aquatic environment. To date, very few studies have used in vivo magnetic resonance imaging (MRI) to uncover the physiological mechanisms that respond to or compensate for these challenges. This paper provides an overview of what has been accomplished thus far by using MRI to study the environmental physiology of fish. It introduces the reader to the use of small teleost fish such as carp (12 cm, 60 g) and eelpout (25 cm, 50 g) as models for such research and to provide new perceptions into the applicability of MRI tools based on new insights into the nature of MRI contrast. Representative MRI studies have made contributions to the identification of the lack of cell volume repair in stenohaline fish during osmotic stress. They have studied the underlying physiological mechanisms of brain anoxia tolerance in fish and have qualified the role of the cardio-circulatory system in setting thermal tolerance windows of fish.
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Affiliation(s)
- A Van der Linden
- Bio-Imaging Lab, Department, Biomedical Sciences, University of Antwerp, Middelheim Campus, Groenenborgerlaan 171, 2020, Antwerp, Belgium.
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12
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Parkerson KA, Sontheimer H. Contribution of chloride channels to volume regulation of cortical astrocytes. Am J Physiol Cell Physiol 2003; 284:C1460-7. [PMID: 12606317 DOI: 10.1152/ajpcell.00603.2002] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of this study was to determine the relative contribution of Cl(-) channels to volume regulation of cultured rat cortical astrocytes after hypotonic cell swelling. Using a Coulter counter, we showed that cortical astrocytes regulate their cell volume by approximately 60% within 45 min after hypotonic challenge. This volume regulation was supported when Cl(-) was replaced with Br(-), NO(3)(-), methanesulfonate(-), or acetate(-) but was inhibited when Cl(-) was replaced with isethionate(-) or gluconate(-). Additionally, substitution of Cl(-) with I(-) completely blocked volume regulation. Volume regulation was unaffected by furosemide or bumetanide, blockers of KCl transport, but was inhibited by Cl(-) channel blockers, including 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), and niflumic acid. Surprisingly, the combination of Cd(2+) with NPPB, DIDS, or niflumic acid inhibited regulation to a greater extent than any of these drugs alone. Volume regulation did not differ among astrocytes cultured from different brain regions, as cerebellar and hippocampal astrocytes exhibited behavior identical to that of cortical astrocytes. These data suggest that Cl(-) flux through ion channels rather than transporters is essential for volume regulation of cultured astrocytes in response to hypotonic challenge.
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Affiliation(s)
- Kimberly A Parkerson
- Department of Neurobiology, Civitan International Research Center, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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Ballatori N, Villalobos AR. Defining the molecular and cellular basis of toxicity using comparative models. Toxicol Appl Pharmacol 2002; 183:207-220. [PMID: 12383712 DOI: 10.1006/taap.2002.9488] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A critical element of any experimental design is the selection of the model that will be used to test the hypothesis. As Claude Bernard proposed over 100 years ago "the solution of a physiological or pathological problem often depends solely on the appropriate choice of the animal for the experiment so as to make the result clear and searching." Likewise, the Danish physiologist August Krogh in 1929 wrote that "For a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied." This scientific principle has been validated repeatedly in the intervening years as investigators have described unique models that exploit natural differences in chemical and molecular structure, biochemical function, or physiological response between different cells, tissues, and organisms to address specific hypotheses. Despite the power of this comparative approach, investigators have generally been reluctant to utilize nonmammalian or nonclassical experimental models to address questions of human biology. The perception has been that studies in relatively simple or evolutionarily ancient organisms would provide little insight into "complex" human biology. This perception, although always somewhat misguided, is now even less tenable given the results of the genome sequencing projects, which demonstrate that the human genome is remarkably similar to that of evolutionarily ancient organisms. Thus, the various life forms on Earth share much more in common then anyone had previously envisioned. This realization provides additional rationale for the use of nonclassical experimental models and provides perhaps the strongest validation of Bernard's and Krogh's assertions. This overview emphasizes some of the special attributes of alternative animal models that may be exploited to define the molecular and cellular basis of toxicity. For each attribute, selected examples of animal models and experimental approaches are presented. It focuses on the areas of neurotoxicology, reproductive and developmental toxicology, organ systems toxicology, carcinogenesis, and functional genomics/toxicogenomics and highlights the use of fish, avian, Drosophila, Caenorhabditis elegans, and yeast models in such studies.
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Affiliation(s)
- Nazzareno Ballatori
- Department of Environmental Medicine, University of Rochester School of Medicine, New York 14642, USA.
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Perrino LA, Pierce SK. Betaine aldehyde dehydrogenase kinetics partially account for oyster population differences in glycine betaine synthesis. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/(sici)1097-010x(20000215)286:3<238::aid-jez3>3.0.co;2-e] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Van der Linden A, Vanaudenhove M, Verhoye M, De Boeck G, Blust R. Osmoregulation of the common carp (Cyprinus carpio) when exposed to an osmotic challenge assessed in-vivo and non-invasively by diffusion- and T2-weighted magnetic resonance imaging. Comp Biochem Physiol A Mol Integr Physiol 1999. [DOI: 10.1016/s1095-6433(99)00124-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Comparative time courses of inorganic and organic osmolyte accumulation as horseshoe crabs (Limulus polyphemus) adapt to high salinity. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0300-9629(92)90015-i] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sreedevi P, Sivaramakrishna B, Suresh A, Radhakrishnaiah K. Effect of nickel on some aspects of protein metabolism in the gill and kidney of the freshwater fish, Cyprinus carpio L. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 1992; 77:59-63. [PMID: 15091978 DOI: 10.1016/0269-7491(92)90158-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/1991] [Revised: 08/28/1991] [Accepted: 09/06/1991] [Indexed: 05/24/2023]
Abstract
Nickel has an adverse effect on some aspects of protein metabolism of the freshwater fish, Cyprinus carpio. The main changes observed were: (a) Decrease in soluble, structural and total proteins, AlAT and AAT activities with an increase in the levels of free amino acids, protease and GDH activities and ammonia in the gill and kidney at 1, 2, 3, and 4 days of exposure to a lethal concentration, 40 mg litre(-1) of nickel; (b) Increase in soluble, structural and total proteins, free amino acids and the activities of protease, AlAT, AAT and GDH with a decrease in ammonia and urea in these organs at 1, 5, 10 and 15 days of exposure to sublethal concentration, 8 mg litre(-1); (c) The magnitude in these changes increased over time with both concentrations of the metal, and was more marked in gill than in kidney.
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Affiliation(s)
- P Sreedevi
- Department of Zoology, Sri Krishnadevaraya University, Anantapur-515 003, A.P., India
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Woolverton WS, Githens S, O'Dell-Smith R, Bartell CK. Rat renal papillary tissue explants survive and produce epithelial monolayers in culture media made hyperosmotic with sodium chloride and urea. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1990; 256:189-99. [PMID: 2280248 DOI: 10.1002/jez.1402560209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The capacity of papillary cells to adapt to elevated osmotic concentrations is unusual among mammalian cells. This capacity was evaluated by using primary tissue culture. Viability and growth of cells in rat renal papillary tissue explants were assessed after culture in media adjusted with urea and sodium chloride to various osmotic concentrations between 300 and 1,500 mOsm/kg water. The survival of cells, including cells resembling those of the collecting ducts and the loop of Henle, was greatest in medium adjusted to 1,000 mOsm with equiosmolar amounts of the two solutes. At 1,500 mOsm only cuboidal tubular epithelium resembling collecting duct epithelial cells survived. In contrast, cells of cortical tissue survived and grew at 300 and 640 mOsm, but not at 1,000 mOsm or above. Epithelial monolayers appeared to proliferate from collecting ducts and spread over the surface of the explants as well as onto the glass surface in the culture dish. Epithelial growth of medullary tissue was most rapid at 300 mOsm and was slower at 700 and 1,000 mOsm. Monolayers did not form at 1,500 mOsm; however, epithelial overgrowth of explants did occur. Hydropenia in the donor animal did not significantly affect the viability or growth of cultured papillary tissue. Explants cultured for 5 days at 300 mOsm followed by a stepwise increase in medium osmolality to 1,100 or 1,500 mOsm and cultured for 3 more days showed low or no survival whereas explants cultured at 700 mOsm survived such increases. Explants cultured for 5 days at 1,500 mOsm survived and grew monolayers when lowered to 300 mOsm. Poor viability and no epithelial proliferation were observed in explants cultured in medium adjusted to 900 mOsm with either urea or sodium chloride alone, suggesting that a mixture of the two solutes in the extracellular space, as found in vivo, may be essential in achieving elevated osmolalities.
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Affiliation(s)
- W S Woolverton
- Department of Biological Sciences, University of New Orleans, Louisiana 70148
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Beck FX, Dörge A, Thurau K. Cellular osmoregulation in the renal papilla. KLINISCHE WOCHENSCHRIFT 1988; 66:843-8. [PMID: 3054272 DOI: 10.1007/bf01728945] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The cells of the renal papilla are subject to extreme variations in extracellular tonicity. To obtain more insight into the mechanisms whereby these cells adapt osmotically to these unique environmental conditions, elements were measured in individual cells of the rat renal papilla in antidiuresis and after prolonged furosemide administration. In antidiuresis cell sodium, chloride and potassium concentrations did not differ fundamentally from those observed in tubule cells exposed to isotonic surroundings such as in proximal tubule cells. The marked fall in extracellular electrolyte concentrations induced by furosemide was paralleled by a far less pronounced decline in intracellular sodium, chloride and potassium concentrations. These data indicate that papillary cells achieve osmoadaptation to widely differing extracellular tonicities mainly by varying the intracellular concentrations of osmotically active substances other than inorganic electrolytes. Since high concentrations of organic osmolytes (sorbitol, inositol, glycerophosphorylcholine and other trimethylamines) have been detected in the papilla and since the tissue contents of these compounds have been shown to vary in parallel with urine osmolality, it may be concluded that metabolically inert, organic osmolytes play a dominant role in the osmoregulation of renal papillary cells.
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Affiliation(s)
- F X Beck
- Physiologisches Institut der Universität München
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Volume Regulation in Cells of Euryhaline Invertebrates. CELL VOLUME CONTROL: FUNDAMENTAL AND COMPARATIVE ASPECTS IN ANIMAL CELLS 1987. [DOI: 10.1016/s0070-2161(08)60372-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Beck F, Dörge A, Rick R, Thurau K. Intra- and extracellular element concentrations of rat renal papilla in antidiuresis. Kidney Int 1984; 25:397-403. [PMID: 6727135 DOI: 10.1038/ki.1984.30] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The element concentrations in various intra- and extracellular compartments of the tip of the rat renal papilla were determined during antidiuresis using electron microprobe analysis. Urinary concentrations (means +/- SEM) were: urea, 1509 +/- 116; potassium, 268 +/- 32; sodium, 62 +/- 19 mmoles X 1(-1); and osmolality, 2548 +/- 141 mOsm X kg-1. Electrolyte concentrations in the interstitial space were: sodium, 437 +/- 19; chloride, 438 +/- 20; and potassium, 35 +/- 2 mmoles X kg-1 wet wt. The vasa recta plasma exhibited almost identical element concentrations. The values in the papillary collecting duct cells were: sodium, 28 +/- 1; chloride, 76 +/- 3; potassium, 135 +/- 3; and phosphorus, 316 +/- 7 mmoles X kg-1 wet wt. Similar concentrations were observed in the papillary epithelial cells. In interstitial cells potassium and phosphorus concentrations were virtually identical to those of the collecting duct cells, whereas sodium and chloride concentrations were higher by about 30 mmoles X kg-1 wet wt. The element composition of the various papillary cells is, thus, not substantially different from that of proximal tubular cells. This finding demonstrates that cellular accumulation of electrolytes is not the regulatory mechanism by which papillary cells adapt osmotically to their high environmental osmolality and sodium chloride concentration.
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The significance of the amino acids during osmotic adjustment in teleost fish—I. Changes in the euryhaline Sarotherodon mossambicus. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0300-9629(83)90543-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Volume regulation in the red coelomocytes ofGlycera dibranchiata: An interaction of amino acid and K+ effluxes. J Comp Physiol B 1983. [DOI: 10.1007/bf00689911] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Hegab S, Hanke W. Electrolyte changes and volume regulatory processes in the carp (Cyprinus carpio) during osmotic stress. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/0300-9629(82)90384-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Bulger RE, Beeuwkes R, Saubermann AJ. Application of scanning electron microscopy to x-ray analysis of frozen-hydrated sections. III. Elemental content of cells in the rat renal papillary tip. J Cell Biol 1981; 88:274-80. [PMID: 7204493 PMCID: PMC2111754 DOI: 10.1083/jcb.88.2.274] [Citation(s) in RCA: 75] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The electrolyte and water content of cellular and interstitial compartments in the renal papilla of the rat was determined by x-ray microanalysis of frozen-hydrated tissue sections. Papillae from rats on ad libitum water were rapidly frozen in a slush of Freon 12, and sectioned in a cryomicrotome at -30 to -40 degrees C. Frozen 0.5-micrometer sections were mounted on carbon-coated nylon film over a Be grid, transferred cold to the scanning microscope, and maintained at -175 degrees C during analysis. The scanning transmission mode was used for imaging. Structural preservation was of good quality and allowed identification of tissue compartments. Tissue mass (solutes + water) was determined by continuum radiation from regions of interest. After drying in the SEM, elemental composition of morphologically defined compartments (solutes) was determined by analysis of specific x-rays, and total dry mass by continuum. Na, K, Cl, and H2O contents in collecting-duct cells (CDC), papillary epithelial cells (PEC), and interstitial cells (IC) and space were measured. Cells had lower water content (mean 58.7%) than interstitium (77.5%). Intracellular K concentrations (millimoles per kilogram wet weight) were unremarkable (79-156 mm/kg wet weight); P was markedly higher in cells than in interstitium. S was the same in all compartments. Intracellular Na levels were extremely high (CDC, 344 +/- 127 SD mm/kg wet weight; PEC, 287 +/- 105; IC, 898 +/- 194). Mean interstitial Na was 590 +/- 119 mm/kg wet weight. CI values paralleled those for Na. If this Na is unbound, then these data suggest that renal papillary interstitial cells adapt to their hyperosmotic environment by a Na-uptake process.
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Gilles R. Mechanisms of volume regulation and control of the level of intracellular osmotic effectors. JPEN J Parenter Enteral Nutr 1980; 4:121-30. [PMID: 7401257 DOI: 10.1177/014860718000400210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Brühmann M, Hanke W. Cell volume regulation in juveniles of xenopus laevis in hypertonic urea solution. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/s0300-9629(80)80010-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Effect of a hypo-osmotic shock on the volume and the ion content of rat kidney cortex slices. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/0300-9629(80)90382-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Schröck H, Hanke W. Cell volume regulation in tadpoles of Xenopus laevis in hypertonic salt solution. ACTA ACUST UNITED AC 1979. [DOI: 10.1016/0300-9629(79)90610-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kevers C, P�queux A, Gilles R. Effects of an hypo-osmotic shock on Na+, K+ and Cl? levels in isolated axons ofCarcinus maenas. ACTA ACUST UNITED AC 1979. [DOI: 10.1007/bf00686995] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Assem H, Hankf W. Volume regulation of muscle cells in the euryhaline teleost, Tilapia mossambica. ACTA ACUST UNITED AC 1979. [DOI: 10.1016/0300-9629(79)90423-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Schmidt-Nielsen B. Volume regulation of muscle fibres in the killifish, Fundulus heteroclitus. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1977; 199:411-8. [PMID: 850121 DOI: 10.1002/jez.1401990315] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cell volume regulation has been observed in vitro in many tissues. In the killifish it was studied in vivo during transfer from SW to FW and from FW to SW. It was found that the cell water content in acclimated fish varies inversely with the osmolality of the medium. During transfer from SW to FW the plasma osmolality decreased. Cell swelling was prevented through net loss of solutes from the cells. The solutes lost were not potassium or sodium and are presumed to be organic solutes. Dund no significant increase in cell solute content could be found during eight hours. During prolonged acclimation cell water content returns to a higher value.
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Guderley H. Muscle and hypodermal ion concentrations in Cancer magister: changes with the molt cycle. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1977; 56:155-9. [PMID: 11926 DOI: 10.1016/0300-9629(77)90177-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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