title: Claudins in a primary cultured puffer fish (Tetraodon nigroviridis) gill epithelium model alter in response to acute seawater exposure.
abstract: Gill epithelium permeability and qualitative/quantitative aspects of gill claudin (cldn) tight junction (TJ) protein transcriptomics were examined with a primary cultured model gill epithelium developed using euryhaline puffer fish (Tetraodon nigroviridis) gills. The model was prepared using seawater-acclimated fish gills and was cultured on permeable cell culture filter supports. The model is composed of 1-2 confluent layers of gill pavement cells (PVCs), with the outer layer exhibiting prominent apical surface microridges and TJs between adjacent cells. During development of electrophysiological characteristics, the model exhibits a sigmoidal increase in transpithelial resistance (TER) and plateaus around 30 kΩcm(2). At this point paracellular movement of [(3)H]polyethylene glycol (PEG) 4000 was low at ~1.75 cm s(-1)×10(-7). When exposed to apical seawater (SW) epithelia exhibit a marked decrease in TER while PEG flux remained unchanged for at least 6 h. In association with this, transcript encoding cldn TJ proteins cldn3c, -23b, -27a, -27c, -32a and -33b increased during the first 6 h while cldn11a decreased. This suggests that these proteins are involved in maintaining barrier properties between gill PVCs of SW fishes. Gill cldn mRNA abundance also altered 6 and 12 h following abrupt SW exposure of puffer fish, but in a manner that differed qualitatively and quantitatively from the cultured model. This most likely reflects the cellular heterogeneity of whole tissue and/or the contribution of the endocrine system in intact fish. The current study provides insight into the physiological and transcriptomic response of euryhaline fish gill cells to a hyperosmotic environment.
authors.affiliation: Department of Biology, York University, Toronto, ON M3J 1P3, Canada.
authors.forename: Phuong
authors.initials: P
authors.lastname: Bui
authors.affiliation: Department of Biology, York University, Toronto, ON M3J 1P3, Canada. Electronic address: spk@yorku.ca.
authors.forename: Scott P
authors.initials: SP
authors.lastname: Kelly
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D057167:Claudins / Q000235:genetics*; D017097:Electric Impedance; D055724:Electrophysiological Phenomena; D004847:Epithelial Cells / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D004848:Epithelium / Q000378:metabolism / Q000648:ultrastructure; D029941:Fish Proteins / Q000235:genetics*; D020869:Gene Expression Profiling / Q000379:methods; D005880:Gills / Q000166:cytology / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D011092:Polyethylene Glycols / Q000378:metabolism; D061251:Primary Cell Culture; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012623:Seawater; D023721:Tetraodontiformes / Q000235:genetics*; D014316:Tritium
chemical_list: D057167:Claudins; D029941:Fish Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D014316:Tritium; D011092:Polyethylene Glycols
keywords: Claudin; Gill; Pavement cell; Permeability; Tight junction