XB-ART-15186
FEBS Lett
1998 Mar 20;4251:71-4.
Show Gene links
Show Anatomy links
The Na+,K+-ATPase carrying the carboxy-terminal Ca2+/calmodulin binding domain of the Ca2+ pump has 2Na+,2K+ stoichiometry and lost charge movement in Na+/Na+ exchange.
???displayArticle.abstract???
An altered ion-transport stoichiometry from 3Na+,2K+ to 2Na+,2K+ is observed in a chimeric Na+,K+ATPase, which carries the Ca2+/calmodulin binding domain (CBD) of the plasma membrane Ca2+-ATPase at its carboxy-terminus [Zhao et al., FEBS Lett. 408 (1997) 271-2751. The ouabain-resistant mutant of this chimera (ORalpha1-CBD) was constructed to further investigate the effect of the CBD on ion-transport properties. The ORalpha1-CBD still shows the 2Na+,2K+ stoichiometry. The loss of electrogenicity is accompanied by the disappearance of transient charge movements in the Na+/Na+ exchange mode. We conclude that the binding of the third Na+ ion, but not of the two others, in 3Na+,2K+ transport mode apparently senses the electric field, and that the voltage-dependent Na+ binding is likely to be lost in the chimera with CBD.
???displayArticle.pubmedLink??? 9541009
???displayArticle.link??? FEBS Lett
???displayArticle.grants???
Species referenced: Xenopus laevis
Genes referenced: tbx2