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<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Ian S. McKay</dc:contributor>
  <dc:contributor>Victor Koltenyuk</dc:contributor>
  <dc:contributor>Nastasia N. Nelson</dc:contributor>
  <dc:contributor>Sean C. Lema</dc:contributor>
  <dc:contributor>Stephen D. McCormick</dc:contributor>
  <dc:creator>Jason P. Breves</dc:creator>
  <dc:date>2022</dc:date>
  <dc:description>&lt;p&gt;The life history of Atlantic salmon (&lt;i&gt;Salmo salar&lt;/i&gt;) includes an initial freshwater phase (parr) that precedes a springtime migration to marine environments as smolts. The development of osmoregulatory systems that will ultimately support the survival of juveniles upon entry into marine habitats is a key aspect of smoltification. While the acquisition of seawater tolerance in all euryhaline species demands the concerted activity of specific ion pumps, transporters, and channels, the contributions of Na&lt;sup&gt;+&lt;/sup&gt;/HCO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;−&lt;/sup&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;cotransporter 1 (Nbce1) to salinity acclimation remain unresolved. Here, we investigated the branchial and intestinal expression of three&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Na&lt;/i&gt;&lt;sup&gt;+&lt;/sup&gt;&lt;i&gt;/HCO&lt;/i&gt;&lt;sub&gt;&lt;i&gt;3&lt;/i&gt;&lt;/sub&gt;&lt;sup&gt;&lt;i&gt;−&lt;/i&gt;&lt;/sup&gt;&lt;i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;cotransporter 1&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;isoforms, denoted&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;nbce1.1&lt;/i&gt;,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;-1.2a&lt;/i&gt;, and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;-1.2b&lt;/i&gt;. Given the proposed role of Nbce1 in supporting the absorption of environmental Na&lt;sup&gt;+&lt;/sup&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;by ionocytes, we first hypothesized that expression of a branchial&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;nbce1&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;transcript (&lt;i&gt;nbce1.2a&lt;/i&gt;) would be attenuated in salmon undergoing smoltification and following seawater exposure. In two separate years, we observed spring increases in branchial Na&lt;sup&gt;+&lt;/sup&gt;/K&lt;sup&gt;+&lt;/sup&gt;-ATPase activity,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Na&lt;/i&gt;&lt;sup&gt;+&lt;/sup&gt;&lt;i&gt;/K&lt;/i&gt;&lt;sup&gt;+&lt;/sup&gt;&lt;i&gt;/2Cl&lt;/i&gt;&lt;sup&gt;&lt;i&gt;−&lt;/i&gt;&lt;/sup&gt;&lt;i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;cotransporter 1&lt;/i&gt;, and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;cystic fibrosis transmembrane regulator 1&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;expression characteristic of smoltification, whereas there were no attendant changes in&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;nbce1.2a&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;expression. Nonetheless, branchial&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;nbce1.2a&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;levels were reduced in parr and smolts within 2&amp;nbsp;days of seawater exposure. In the intestine, gene transcript abundance for&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;nbce1.1&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;increased from spring to summer in the anterior intestine, but not in the posterior intestine or pyloric caeca, and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;nbce1.1&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;-1.2b&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;expression in the intestine showed season-dependent transcriptional regulation by seawater exposure. Collectively, our data indicate that tissue-specific modulation of all three&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;nbce1&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;isoforms underlies adaptive responses to seawater.&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1007/s00360-022-01443-8</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Springer</dc:publisher>
  <dc:title>Na+/HCO3- cotransporter 1 (nbce1) isoform gene expression during smoltification and seawater acclimation of Atlantic salmon</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>