Blog
About

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

Novel vasotocin-regulated aquaporins expressed in the ventral skin of semiaquatic anuran amphibians: evolution of cutaneous water-absorbing mechanisms.

Read this article at

ScienceOpenPublisherPubMed
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

      Until now, it was believed that only one form of arginine vasotocin (AVT)-regulated aquaporin (AQP) existed to control water absorption from the ventral skin of semiaquatic anuran amphibians, eg, AQP-rj3(a) in Rana japonica. In the present study, we have identified a novel form of ventral skin-type AQP, AQP-rj3b, in R. japonica by cDNA cloning. The oocyte swelling assay confirmed that AQP-rj3b can facilitate water permeability. Both AQP-rj3a and AQP-rj3b were expressed abundantly in the ventral hindlimb skin and weakly in the ventral pelvic skin. For the hindlimb skin, water permeability was increased in response to AVT, although the hydroosmotic response was not statistically significant in the pelvic skin. Isoproterenol augmented water permeability of the hindlimb skin, and the response was inhibited by propranolol. These events were well correlated with the intracellular trafficking of the AQPs. Immunohistochemistry showed that both AQP-rj3 proteins were translocated from the cytoplasmic pool to the apical membrane of principal cells in the first-reacting cell layer of the hindlimb skin after stimulation with AVT and/or isoproterenol. The type-b AQP was also found in R. (Lithobates) catesbeiana and R. (Pelophylax) nigromaculata. Molecular phylogenetic analysis indicated that the type-a is closely related to ventral skin-type AQPs from aquatic Xenopus, whereas the type-b is closer to the AQPs from terrestrial Bufo and Hyla, suggesting that the AQPs from terrestrial species are not the orthologue of the AQPs from aquatic species. Based on these results, we propose a model for the evolution of cutaneous water-absorbing mechanisms in association with AQPs.

      Related collections

      Author and article information

      Affiliations
      [1 ] Department of Biology, Faculty of Science (Y.Sa., R.O., S.T., M.S.), and Integrated Bioscience Section, Graduate School of Science and Technology (Y.O., Y.Sh., R.O., S.T., M.S.), Shizuoka University, Shizuoka 422-8529, Japan.
      Journal
      Endocrinology
      Endocrinology
      1945-7170
      0013-7227
      Jun 2014
      : 155
      : 6
      24654785
      10.1210/en.2013-1928

      Comments

      Comment on this article