Regulation of Na+/K+ ATPase transport velocity by RNA editing.
Because firing properties and metabolic rates vary widely, neurons require different transport rates from their Na(+)/K(+) pumps in order to maintain ion homeostasis. In this study we show that Na(+)/K(+) pump activity is tightly regulated by a novel process, RNA editing. Three codons within the squ...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2010-11-01
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| Series: | PLoS Biology |
| Online Access: | http://europepmc.org/articles/PMC2990702?pdf=render |
| Summary: | Because firing properties and metabolic rates vary widely, neurons require different transport rates from their Na(+)/K(+) pumps in order to maintain ion homeostasis. In this study we show that Na(+)/K(+) pump activity is tightly regulated by a novel process, RNA editing. Three codons within the squid Na(+)/K(+) ATPase gene can be recoded at the RNA level, and the efficiency of conversion for each varies dramatically, and independently, between tissues. At one site, a highly conserved isoleucine in the seventh transmembrane span can be converted to a valine, a change that shifts the pump's intrinsic voltage dependence. Mechanistically, the removal of a single methyl group specifically targets the process of Na(+) release to the extracellular solution, causing a higher turnover rate at the resting membrane potential. |
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| ISSN: | 1544-9173 1545-7885 |