Plasma membrane abundance of human aquaporin 5 is dynamically regulated by multiple pathways
Cast your vote
You can rate an item by clicking the amount of stars they wish to award to this item.
When enough users have cast their vote on this item, the average rating will also be shown.
Your vote was cast
Thank you for your feedback
Thank you for your feedback
Conner, Matthew T.
Conner, Alex C.
MetadataShow full item record
Abstract© 2015 Kitchen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Aquaporin membrane protein channels mediate cellular water flow. Human aquaporin 5 (AQP5) is highly expressed in the respiratory system and secretory glands where it facilitates the osmotically-driven generation of pulmonary secretions, saliva, sweat and tears. Dysfunctional trafficking of AQP5 has been implicated in several human disease states, including Sjögren's syndrome, bronchitis and cystic fibrosis. In order to investigate how the plasma membrane expression levels of AQP5 are regulated, we studied real-time translocation of GFP-tagged AQP5 in HEK293 cells. We show that AQP5 plasma membrane abundance in transfected HEK293 cells is rapidly and reversibly regulated by at least three independent mechanisms involving phosphorylation at Ser156, protein kinase A activity and extracellular tonicity. The crystal structure of a Ser156 phosphomimetic mutant indicates that its involvement in regulating AQP5 membrane abundance is not mediated by a conformational change of the carboxy-terminus. We suggest that together these pathways regulate cellular water flow.
CitationKitchen P., Öberg F., Sjöhamn J., Hedfalk K., Bill R. M., Conner A. C., et al. (2015) Plasma membrane abundance of human Aquaporin 5 Is dynamically regulated by multiple pathways. PLoS ONE 10(11): e0143027. doi:10.1371/journal.pone.0143027.
PublisherPublic Library of Science (PLoS)
SponsorsThis work was supported by the Swedish Research Council (www.vr.se) grants 2009-360 and 2010-5208 (to STH), European Commission Framework Programme 7 (http://ec.europa.eu/research/fp7/index_en.cfm) Grant 201924 EDICT (to RMB) and by the Engineering and Physical Sciences Research Council (https://www.epsrc.ac.uk) through the Molecular Organisation and Assembly in Cells Doctoral Training Centre, University of Warwick, grant number EP/F500378/1 (PK).
Except where otherwise noted, this item's license is described as Licence for published version: Creative Commons Attribution 4.0 International
- Novel phosphorylation of aquaporin-5 at its threonine 259 through cAMP signaling in salivary gland cells.
- Authors: Hasegawa T, Azlina A, Javkhlan P, Yao C, Akamatsu T, Hosoi K
- Issue date: 2011 Sep
- Protein kinase A-regulated membrane trafficking of a green fluorescent protein-aquaporin 5 chimera in MDCK cells.
- Authors: Kosugi-Tanaka C, Li X, Yao C, Akamatsu T, Kanamori N, Hosoi K
- Issue date: 2006 Apr
- Transient receptor potential vanilloid 4 regulates aquaporin-5 abundance under hypotonic conditions.
- Authors: Sidhaye VK, Güler AD, Schweitzer KS, D'Alessio F, Caterina MJ, King LS
- Issue date: 2006 Mar 21
- Mechanisms Underlying Activation of α₁-Adrenergic Receptor-Induced Trafficking of AQP5 in Rat Parotid Acinar Cells under Isotonic or Hypotonic Conditions.
- Authors: Bragiel AM, Wang D, Pieczonka TD, Shono M, Ishikawa Y
- Issue date: 2016 Jun 28
- Opposing Effects of cAMP and T259 Phosphorylation on Plasma Membrane Diffusion of the Water Channel Aquaporin-5 in Madin-Darby Canine Kidney Cells.
- Authors: Koffman JS, Arnspang EC, Marlar S, Nejsum LN
- Issue date: 2015
Showing items related by title, author, creator and subject.
Structural determinants of oligomerization of the aquaporin-4 channelKitchen, P; Conner, MT; Bill, RM; Conner, AC; From the Molecular Assembly and Organisation in Cells Doctoral Training Centre, University of Warwick, Coventry CV4 7AL, the School of Life & Health Sciences and Aston Research Centre for Healthy Ageing, Aston University, Aston Triangle, Birmingham, B4 7ET, and the Institute of Clinical Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom. (American Society for Biochemistry & Molecular Biology (ASBMB), 2016-01-19)©2016 by The American Society for Biochemistry and Molecular Biology, Inc. The aquaporin (AQP) family of integral membrane protein channels mediate cellular water and solute flow. Although qualitative and quantitative differences in channel permeability, selectivity, subcellular localization, and trafficking responses have been observed for different members of the AQP family, the signature homotetrameric quaternary structure is conserved. Using a variety of biophysical techniques, we show that mutations to an intracellular loop (loop D) of human AQP4 reduce oligomerization. Non-tetrameric AQP4 mutants are unable to relocalize to the plasma membrane in response to changes in extracellular tonicity, despite equivalent constitutive surface expression levels and water permeability to wild-type AQP4. A network of AQP4 loop D hydrogen bonding interactions, identified using molecular dynamics simulations and based on a comparative mutagenic analysis of AQPs 1, 3, and 4, suggest that loop D interactions may provide a general structural framework for tetrameric assembly within theAQPfamily.
Investigation of the role of SDHB inactivation in sporadic phaeochromocytoma and neuroblastomaAstuti, D; Morris, M; Krona, C; Abel, F; Gentle, D; Martinsson, T; Kogner, P; Neumann, HPH; Voutilainen, R; Eng, C; et al. (Springer Nature, 2004-10-26)Germline mutations in the succinate dehydrogenase (SDH) (mitochondrial respiratory chain complex II) subunit B gene, SDHB, cause susceptibility to head and neck paraganglioma and phaeochromocytoma. Previously, we did not identify somatic SDHB mutations in sporadic phaeochromocytoma, but SDHB maps to 1p36, a region of frequent loss of heterozygosity (LOH) in neuroblastoma as well. Hence, to evaluate SDHB as a candidate neuroblastoma tumour suppressor gene (TSG) we performed mutation analysis in 46 primary neuroblastomas by direct sequencing, but did not identify germline or somatic SDHB mutations. As TSGs such as RASSF1A are frequently inactivated by promoter region hypermethylation, we designed a methylation-sensitive PCR-based assay to detect SDHB promoter region methylation. In 21% of primary neuroblastomas and 32% of phaeochromocytomas (32%) methylated (and unmethylated) alleles were detected. Although promoter region methylation was also detected in two neuroblastoma cell lines, this was not associated with silencing of SDHB expression, and treatment with a demethylating agent (5-azacytidine) did not increase SDH activity. These findings suggest that although germline SDHB mutations are an important cause of phaeochromocytoma susceptibility, somatic inactivation of SDHB does not have a major role in sporadic neural crest tumours and SDHB is not the target of 1p36 allele loss in neuroblastoma and phaeochromocytoma. © 2004 Cancer Research UK.
Cell-Penetrating PeptidesHowl, John; Jones, Sarah (2015)The multi-domain architecture of many human proteins provides a structural basis for the physical maintenance of interactomes, or networks of protein-protein interactions (PPIs), that are so obviously crucial to cellular functions. Moreover, the structural and electrostatic complementarity provided by PPI interfaces, predominantly located on protein surfaces, is a fundamental component of signal transduction events that are known to be compromised in human diseases including many cancers.The pharmacokinetic advantages provided by cell-penetrating peptides (CPPs) are entirely compatible with the development of intrinsically permeable agents capable of modulating intracellular PPIs. Thus, the term bioportide is a useful descriptor of numerous bioactive CPPs that are distinct from the more usual inert CPP vectors. Herein we illustrate a generic strategy, predominantly centered upon the identification of cationic peptides derived from helical protein domains, which offers a reliable platform to identify bioportides capable of modulating intracellular signal transduction events. In addition, we describe robust methodologies to determine the precise intracellular distribution of fluorescent bioportides and present assays routinely employed to screen for the detrimental pharmacodynamic properties often exhibited by both CPPs and bioportides; namely adverse cytotoxicity and the receptor-independent stimulation of mast cell secretion.