Evol Ecol Res 20: 349-363 (2019) Full PDF if your library subscribes.
Gill Na+/K+-ATPase in the Threespine stickleback (Gasterosteus aculeatus): changes in transcript levels and sites of expression during acclimation to seawater
Makoto Kusakabe1,2, Seiichi Mori3 and Jun Kitano4
1Department of Biological Sciences, Faculty of Science, Shizuoka University, Surugaku, Shizuoka, Japan, 2Department of Marine Bioscience, Atmosphere and Ocean Research Institute, University of Tokyo, Kashiwa, Chiba, Japan, 3Biological Laboratory, Gifu-keizai University, Ogaki, Gifu, Japan and 4Ecological Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
Correspondence: M. Kusakabe, Department of Biological Sciences, Faculty of Science, Shizuoka University, Surugaku, Shizuoka, Japan. email: email@example.com
Background: Na+/K+-ATPase (NKA) in the gills is a key contributor to osmoregulation in fishes.
Questions: Does gill NKA contribute to the regulation of salinity tolerance in stickleback? Do gill NKA expression patterns during acclimation to seawater differ among stickleback populations that differ in salinity tolerance?
Organisms: Freshwater Threespine stickleback (Gasterosteus aculeatus) from populations in Ono and Gifu, Japan.
Methods: We gradually acclimated the stickleback to 100% seawater. During acclimation, we monitored changes in plasma Na+ concentrations using atomic absorption spectrophotometry and gill NKA transcript levels using qPCR. We determined the sites of gill NKA expression by immunohistochemistry.
Results: Threespine stickleback from Ono were able to acclimate to 100% seawater. In contrast, stickleback from the Gifu population were able to survive in 50% seawater but not 100% seawater. Both ecotypes maintained a plasma Na+ concentration of approximately 150 m
mduring the acclimation process. Patterns of change in NKA transcript and protein expression were similar between the two populations, although they differed in tolerance to salinity. In both populations, gill NKA-positive ionocytes were distributed on the primary filaments and secondary lamellae in fresh water, but during acclimation to seawater the NKA-positive ionocytes on the secondary lamellae disappeared. The cell sizes and densities of NKA-positive ionocytes were higher in fish from Ono than in fish from Gifu, which may explain the difference in salinity tolerance between these two stickleback populations.
Keywords: Gasterosteus aculeatus, gills, Na+/K+-ATPase, plasma Na+, salinity, stickleback.
DOWNLOAD A FREE, FULL PDF COPY
IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.
© 2019 Makoto Kusakabe. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.
Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.
All copies of abstracts and articles must preserve their copyright notice without modification.