TY - JOUR
T1 - Identification of FXYD Protein Genes in a Teleost: Tissue-specific Expression and Response to Salinity Change
AU - Tipsmark, Christian Kølbæk
PY - 2008/2/6
Y1 - 2008/2/6
N2 - It is increasingly clear, that alterations in Na(+),K(+)-ATPase kinetics to fit the demands in specialized cell types, is vital for the enzyme to execute its different physiological roles in diverse tissues. In addition to tissue dependent expression of isoforms of the conventional subunits, alpha- and beta-, auxiliary FXYD proteins appear to be essential regulatory components. The present study identified genes belonging to this family in Atlantic salmon by analysis of expressed sequence tags. Based on the conserved domain of these small membrane proteins, eight expressed FXYD isoforms were identified. Phylogenetic analysis suggests that six isoforms are homologues to the previously identified FXYD2, FXYD5, FXYD6, FXYD7, FXYD8 and FXYD9, while two additional isoforms were found (FXYD11 and FXYD12). Using quantitative PCR, tissue dependent expression of the different isoforms was analyzed in gill, kidney, intestine, heart, muscle, brain and liver. Two isoforms were expressed in several tissues (FXYD5 and FXYD9), while six isoforms were distributed in a discrete manner. In excitable tissues, two isoforms were highly expressed in brain (FXYD6 and FXYD7) and one in skeletal muscle (FXYD8). In osmoregulatory tissues, one isoform was expressed predominantly in gill (FXYD11), one in kidney (FXYD2) and one equally in kidney and intestine (FXYD12). Expression of several FXYD genes in kidney and gill differed between fresh water and seawater salmon suggesting significance during osmoregulatory adaptations. In addition to identify novel FXYD isoforms, these studies are the first to show the tissue dependence in their expression and modulation by salinity in any teleosts. Key words: Atlantic salmon, Na+,K+-ATPase, Osmoregulation, Salmo salar, QPCR.
AB - It is increasingly clear, that alterations in Na(+),K(+)-ATPase kinetics to fit the demands in specialized cell types, is vital for the enzyme to execute its different physiological roles in diverse tissues. In addition to tissue dependent expression of isoforms of the conventional subunits, alpha- and beta-, auxiliary FXYD proteins appear to be essential regulatory components. The present study identified genes belonging to this family in Atlantic salmon by analysis of expressed sequence tags. Based on the conserved domain of these small membrane proteins, eight expressed FXYD isoforms were identified. Phylogenetic analysis suggests that six isoforms are homologues to the previously identified FXYD2, FXYD5, FXYD6, FXYD7, FXYD8 and FXYD9, while two additional isoforms were found (FXYD11 and FXYD12). Using quantitative PCR, tissue dependent expression of the different isoforms was analyzed in gill, kidney, intestine, heart, muscle, brain and liver. Two isoforms were expressed in several tissues (FXYD5 and FXYD9), while six isoforms were distributed in a discrete manner. In excitable tissues, two isoforms were highly expressed in brain (FXYD6 and FXYD7) and one in skeletal muscle (FXYD8). In osmoregulatory tissues, one isoform was expressed predominantly in gill (FXYD11), one in kidney (FXYD2) and one equally in kidney and intestine (FXYD12). Expression of several FXYD genes in kidney and gill differed between fresh water and seawater salmon suggesting significance during osmoregulatory adaptations. In addition to identify novel FXYD isoforms, these studies are the first to show the tissue dependence in their expression and modulation by salinity in any teleosts. Key words: Atlantic salmon, Na+,K+-ATPase, Osmoregulation, Salmo salar, QPCR.
U2 - 10.1152/ajpregu.00454.2007
DO - 10.1152/ajpregu.00454.2007
M3 - Journal article
C2 - 18256141
SN - 0363-6119
VL - 294
SP - R1367-R1378
JO - American Journal of Physiology: Regulatory, Integrative and Comparative Physiology
JF - American Journal of Physiology: Regulatory, Integrative and Comparative Physiology
ER -