Abstract
The epithelial sodium channel (ENaC) is involved in Na+ responses such as Na+ absorption and salt taste. The alpha ENaC subunit (α-ENaC) is expressed in the skin of both the adult and larval (tadpole) bullfrog. α-ENaC expression in the developing bullfrog embryo has not been previously investigated. In this study, the expression of α-ENaC at various stages (Sts.) of bullfrog embryonic development is assessed by western blot and immunofluorescence analysis. Bullfrog α-ENaC (α-fENaC) protein was detected by western blot in embryos at Sts. (Gosner/Shumway) 19, 21 and 25. Immunofluorescence studies indicate that α-fENaC was localized to the embryonic cement glands at St. 18 (muscular response), St. 19 (heart beat) and St. 21 (mouth open and/or cornea transparent), to the external gills at St. 21 and to the outermost cell-layer of the skin at St. 25 (operculum complete). The function(s) of ENaC in these embryonic structures remain to be elucidated.
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Fujimaki-Aoba, K., Tanaka, K., Inomata, R. et al. α-ENaC in bullfrog embryo: expression in cement gland, gills and skin. Cell Tissue Res 355, 103–109 (2014). https://doi.org/10.1007/s00441-013-1724-5
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DOI: https://doi.org/10.1007/s00441-013-1724-5