Potassium-dependent sodium-calcium exchange through the eye of the fly.
In this review, we describe the characterization of a Drosophila sodium/calcium-potassium exchanger, Nckx30C. Sodium/calcium (-potassium) exchangers (NCX and NCKX) are required for the rapid removal of calcium in excitable cells. The deduced protein topology for NCKX30C is similar to that of mammalian NCKX, with 5 hydrophobic domains in the amino terminus separated from 6 at the carboxy-terminal end by a large intracellular loop. NCKX30C functions as a potassium-dependent sodium-calcium exchanger and is expressed in adult neurons and during ventral nerve cord development in the embryo. Nckx30C is expressed in a dorsal/ventral pattern in the eye-antennal disc, suggesting that large fluxes of calcium may be occurring during imaginal disc development in the larvae. NCKX30C may play a critical role in modulating calcium during development as well as in the removal of calcium and maintenance of calcium homeostasis in adults.
Webel
R
R
Department of Ophthalmology & Visual Science, University of Wisconsin, Madison, Wisconsin 53792, USA.
Haug-Collet
K
K
Pearson
B
B
Szerencsei
R T
RT
Winkfein
R J
RJ
Schnetkamp
P P M
PP
Colley
N J
NJ
D000595:Amino Acid Sequence; D000818:Animals; D003624:Darkness; D004330:Drosophila; D007700:Kinetics; D008027:Light; D008969:Molecular Sequence Data; D009799:Ocular Physiological Phenomena; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D019831:Sodium-Calcium Exchanger / Q000737:chemistry* / Q000502:physiology*
D019831:Sodium-Calcium Exchanger; C074530:potassium-dependent sodium-calcium exchanger