QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online November 10, 2003

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Richards, J. G. Articles by Schulte, P. M. Search for Related Content PubMed PubMed Citation Articles by Richards, J. G. Articles by Schulte, P. M.

Na⁺/K⁺-ATPase -isoform switching in gills of rainbow trout (Oncorhynchus mykiss) during salinity transfer

Jeff G. Richards^1,*,, Jeffrey W. Semple^2,*, Jason S. Bystriansky³ and Patricia M. Schulte¹

¹ Department of Zoology, The University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z4
² Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
³ Department of Zoology, University of Guelph, Guelph, Ontario, Canada N1G 2W1

View larger version (19K): [in a new window]   Fig. 1. Phylogenetic analysis of Na+/K+-ATPase -isoform amino acid sequences. Numbers presented at each branch point represent bootstrap values from 500 replicates. Bold-face type indicates Na+/K+-ATPase -isoforms identified in the present study and each is named according to its position in the phylogenetic tree. Fruitfly Na+/K+-ATPase was used as an outgroup.

View larger version (30K): [in a new window]   Fig. 2. Sequence analysis of trout Na+/K+-ATPase -isoforms. (A) N-terminal isoform-specific identity sequence (ns), (B) central isoform-specific identity sequence (cs), (C) predicted structure of the Na+/K+-ATPase -subunit protein showing (f) transmembrane domains, (g) ATP binding site, and (h) a highly conserved area found in all P-type ATPases. Asterisks indicate conserved aas among all isoforms; colons indicate the presence of a conservative aa substitution; stops indicate a semi-conservative aa substitution. (D,E) Percentage variability among isoforms was determined by sliding window analysis on the predicted aa sequence (D) and cDNA sequence (E). Sliding window analysis used overlapping windows of 50 to assess variability.

View larger version (58K): [in a new window]   Fig. 3. Tissue distribution of Na+/K+-ATPase 1a, 1b, 1c, 2 and 3 isoforms in brain, eye, gill, heart, liver, kidney, spleen, intestine, white muscle, red muscle and testis. Tissue distribution was determined using isoform-specific PCR (see text for more details) and ethidium bromide stained gels. Ethidium bromide stained gels give qualitative estimates of expression level, not quantitative. Actin is included as an internal control.

View larger version (13K): [in a new window]   Fig. 4. Plasma cortisol concentrations in trout held in freshwater (Pre) and following transfer to freshwater (filled circles), 40% seawater (open squares) and 80% seawater (filled triangles). Vertical broken line represents the abrupt salinity transfer. Symbols are offset for clarity where necessary. Data are means ± S.E.M. (N=5–8).

View larger version (25K): [in a new window]   Fig. 5. (A) Plasma osmolality, (B) [Na+] and (C) [Cl-] in trout held in freshwater (Pre) and following transfer to freshwater (filled circles), 40% seawater (open squares) and 80% seawater (filled triangles). Vertical broken line represents the abrupt transfer. Symbols are offset for clarity where necessary. Data are means ± S.E.M. (N=5–8). Asterisks indicate significant difference from the control (freshwater) value.

View larger version (12K): [in a new window]   Fig. 6. Gill Na+/K+-ATPase activity in trout held in freshwater (Pre) and following transfer to freshwater (filled circles), 40% seawater (open squares) and 80% seawater (filled triangles). Vertical broken line represents the abrupt transfer. Symbols are offset for clarity where necessary. Data are means ± S.E.M. (N=8). Asterisks indicate significant difference from the control (freshwater) value.

View larger version (22K): [in a new window]   Fig. 7. Gill Na+/K+-ATPase (A) 1a and (B) 1b mRNA in trout held in freshwater (Pre) and following transfer to freshwater (filled circles), 40% seawater (open squares) and 80% seawater (filled triangles). mRNA expression is normalized to the control gene, EF-1, and all data following the transfer are expressed relative to the pre-transfer freshwater gill samples. Vertical broken line represents the abrupt transfer. Symbols are offset for clarity where necessary. Asterisks indicate significant difference from the control (freshwater) value.