The role of NFAT5/TonEBP in establishing an optimal intracellular environment
ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS
Authors: Ho, SN
Abstract
NFAT5/TonEBP, the most recently described member of the rel/NFkappaB/NFAT family of signal-dependent transcription factors, is activated by extracellular hypertonicity-a cellular stress of particular and perhaps unique physiologic relevance to cells of the renal medulla. Accumulating evidence suggests that NFAT5/TonEBP also functions in vivo under isotonic conditions as part of a ubiquitous regulatory mechanism that senses and adjusts available intracellular volume during cell growth to establish an intracellular environment appropriate for optimal cell proliferation. (C) 2003 Elsevier Science (USA). All rights reserved.
NFAT5 genes are part of the osmotic regulatory system in Atlantic salmon (Salmo salar)
MARINE GENOMICS
Authors: Lorgen, Marlene; Jorgensen, Even H.; Jordan, William C.; Martin, Samuel A. M.; Hazlerigg, David G.
Abstract
The anadromous Atlantic salmon utilizes both fresh and salt water (FW and SW) habitats during its life cycle. The parr-smolt transformation (PST) is an important developmental transition from a FW adapted juvenile parr to a SW adapted smolt. Physiological changes in osmoregulatory tissues, particularly the gill, are key is maintaining effective ion regulation during PST. Changes are initiated prior to SW exposure (preparative phase), and are completed when smolts enter the sea (activational phase) Where osmotic stress may directly stimulate changes in gene expression. In this paper we identify 4 nuclear factor of activated T cells (NFAT5, an osmotic stress transcription factor) paralogues in Atlantic salmon, which showed strong homology in characterized functional domains with those identified in other vertebrates. Two of the identified paralogues (NFAT5b1 and NFAT5b2) showed increased expression following transfer from FW to SW. This effect was largest in parr that were maintained under short day photoperiod, and showed the highest increases in chloride ion levels in response to SW exposure. The results of this study suggest that NFAT5 is involved in the osmotic stress response of Atlantic salmon. (C) 2016 The Authors. Published by Elsevier B.V.