For Publishers
DiscoveryMetadataPeer reviewHostingPublishing
For Researchers
JoinPublishReviewCollect
Register
Blog
About
Search
Advanced search
My ScienceOpen
Search
For Publishers
For Researchers
Blog
About
16
views
50
references
 Top references
cited by
13
    
0 reviews
 Review
0
comments
 Comment
0
recommends
+1 Recommend
0 collections
    0
    shares
      579
      similar
       All similar
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Coupling of TRPV6 and TMEM16A in epithelial principal cells of the rat epididymis

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Principal cells regulate the ionic environment of the epididymal lumen via unknown mechanisms. Gao et al. use electrophysiological and pharmacological tools to characterize rat principal cells and reveal a TRPV6-mediated calcium conductance and TMEM16A-mediated calcium-activated chloride conductance.

          Abstract

          The epididymis establishes a congenial environment for sperm maturation and protection. Its fluid is acidic, and the calcium concentration is low and declines along the length of the epididymal tubule. However, our knowledge of ionic currents and mechanisms of calcium homeostasis in rat epididymal epithelial cells remains enigmatic. In this study, to better understand calcium regulation in the epididymis, we use the patch-clamp method to record from single rat cauda epididymal principal cells. We detect a constitutively active Ca 2+ current with characteristics that match the epithelial calcium channel TRPV6. Electrophysiological and pharmacological data also reveal a constitutively active calcium-activated chloride conductance (CaCC). Removal of extracellular calcium attenuates not only the TRPV6-like conductance, but also the CaCC. Lanthanide block is time dependent such that the TRPV6-like component is inhibited first, followed by the CaCC. The putative CaCC blocker niflumic acid partially inhibits whole-cell currents, whereas La 3+ almost abolishes whole-cell currents in principal cells. Membrane potential measurements reveal an interplay between La 3+-sensitive ion channels and those that are sensitive to the specific TMEM16A inhibitor tannic acid. In vivo perfusion of the cauda epididymal tubule shows a substantial rate of Ca 2+ reabsorption from the luminal side, which is dose-dependently suppressed by ruthenium red, a putative blocker of epithelial Ca 2+ channels and CaCC. Finally, we discover messenger RNA for both TRPV6 and TMEM16A in the rat epididymis and show that their proteins colocalize in the apical membrane of principal cells. Collectively, these data provide evidence for a coupling mechanism between TRPV6 and TMEM16A in principal cells that may play an important role in the regulation of calcium homeostasis in the epididymis.

          Related collections

          Most cited references50

          • Record: found
          • Abstract: found
          • Article: not found

          TMEM16A confers receptor-activated calcium-dependent chloride conductance.

          Young Duk Yang, Hawon Cho, Jae Koo … (2008)
          Calcium (Ca(2+))-activated chloride channels are fundamental mediators in numerous physiological processes including transepithelial secretion, cardiac and neuronal excitation, sensory transduction, smooth muscle contraction and fertilization. Despite their physiological importance, their molecular identity has remained largely unknown. Here we show that transmembrane protein 16A (TMEM16A, which we also call anoctamin 1 (ANO1)) is a bona fide Ca(2+)-activated chloride channel that is activated by intracellular Ca(2+) and Ca(2+)-mobilizing stimuli. With eight putative transmembrane domains and no apparent similarity to previously characterized channels, ANO1 defines a new family of ionic channels. The biophysical properties as well as the pharmacological profile of ANO1 are in full agreement with native Ca(2+)-activated chloride currents. ANO1 is expressed in various secretory epithelia, the retina and sensory neurons. Furthermore, knockdown of mouse Ano1 markedly reduced native Ca(2+)-activated chloride currents as well as saliva production in mice. We conclude that ANO1 is a candidate Ca(2+)-activated chloride channel that mediates receptor-activated chloride currents in diverse physiological processes.
          Article 0 comments Cited 395 times – based on 0 reviews     Review now
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            TMEM16A, a membrane protein associated with calcium-dependent chloride channel activity.

            Antonella Caputo, Emanuela Caci, Loretta Ferrera … (2008)
            Calcium-dependent chloride channels are required for normal electrolyte and fluid secretion, olfactory perception, and neuronal and smooth muscle excitability. The molecular identity of these membrane proteins is still unclear. Treatment of bronchial epithelial cells with interleukin-4 (IL-4) causes increased calcium-dependent chloride channel activity, presumably by regulating expression of the corresponding genes. We performed a global gene expression analysis to identify membrane proteins that are regulated by IL-4. Transfection of epithelial cells with specific small interfering RNA against each of these proteins shows that TMEM16A, a member of a family of putative plasma membrane proteins with unknown function, is associated with calcium-dependent chloride current, as measured with halide-sensitive fluorescent proteins, short-circuit current, and patch-clamp techniques. Our results indicate that TMEM16A is an intrinsic constituent of the calcium-dependent chloride channel. Identification of a previously unknown family of membrane proteins associated with chloride channel function will improve our understanding of chloride transport physiopathology and allow for the development of pharmacological tools useful for basic research and drug development.
            Article 0 comments Cited 380 times – based on 0 reviews     Review now
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Expression cloning of TMEM16A as a calcium-activated chloride channel subunit.

              Björn Schroeder, Tong Cheng, Yuh Nung Jan … (2008)
              Calcium-activated chloride channels (CaCCs) are major regulators of sensory transduction, epithelial secretion, and smooth muscle contraction. Other crucial roles of CaCCs include action potential generation in Characean algae and prevention of polyspermia in frog egg membrane. None of the known molecular candidates share properties characteristic of most CaCCs in native cells. Using Axolotl oocytes as an expression system, we have identified TMEM16A as the Xenopus oocyte CaCC. The TMEM16 family of "transmembrane proteins with unknown function" is conserved among eukaryotes, with family members linked to tracheomalacia (mouse TMEM16A), gnathodiaphyseal dysplasia (human TMEM16E), aberrant X segregation (a Drosophila TMEM16 family member), and increased sodium tolerance (yeast TMEM16). Moreover, mouse TMEM16A and TMEM16B yield CaCCs in Axolotl oocytes and mammalian HEK293 cells and recapitulate the broad CaCC expression. The identification of this new family of ion channels may help the development of CaCC modulators for treating diseases including hypertension and cystic fibrosis.
              Article 0 comments Cited 363 times – based on 0 reviews     Review now
                Bookmark
                All references

                Author and article information

                Journal
                Journal ID (nlm-ta): J Gen Physiol
                Journal ID (iso-abbrev): J. Gen. Physiol
                Journal ID (publisher-id): jgp
                Journal ID (hwp): jgp
                Title: The Journal of General Physiology
                Publisher: The Rockefeller University Press
                ISSN (Print): 0022-1295
                ISSN (Electronic): 1540-7748
                Publication date (Print): August 2016
                Volume: 148
                Issue: 2
                Pages: 161-182
                Affiliations
                [1 ]School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
                [2 ]School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China
                Author notes
                Correspondence to Winnie W.C. Shum: shumw@ 123456shanghaitech.edu.cn
                [*]

                D.Y. Gao and B.L. Zhang contributed equally to this paper.

                Article
                Publisher ID: 201611626
                DOI: 10.1085/jgp.201611626
                PMC ID: 4969799
                PubMed ID: 27481714
                SO-VID: 8c1cd7a3-16d9-402a-8572-03d9d56d66a6
                Copyright © © 2016 Gao et al.
                License:

                This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 3.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/3.0/).

                History
                Date received : 21 May 2016
                Date accepted : 13 July 2016
                Funding
                Funded by: National Natural Science Foundation of China http://dx.doi.org/10.13039/501100001809
                Award ID: 31471370
                Categories
                Subject: Research Articles
                Subject: Research Article

                ScienceOpen disciplines: Anatomy & Physiology
                Data availability:
                ScienceOpen disciplines: Anatomy & Physiology

                Comments

                Comment on this article

                scite_

                Similar content579

                See all similar

                Cited by13

                See all cited by