The Na/Ca-K exchanger gene family.
Ca(2+) extrusion driven by both the inward Na(+) gradient as well as the outward K(+) gradient is essential for visual transduction in retinal rod and cone photoreceptors because it removes Ca(2+) that enters photoreceptors via the cGMP-gated and light-sensitive channels. We have cloned rod and cone Na/Ca-K exchanger (NCKX) cDNAs from several species, and we have cloned NCKX cDNAs from lower organisms that lack vertebrate-type vision. Although in situ NCKX physiology has only been documented for vertebrate photoreceptors, it is now clear that NCKX gene products have a much broader distribution pattern. Here, we review some of the structural and functional features that have emerged from our studies on different members of the NCKX gene family.
Szerencsei
Robert T
RT
Department of Biophysics Physiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
Winkfein
Robert J
RJ
Cooper
Conan B
CB
Prinsen
Clemens
C
Kinjo
Tashi G
TG
Kang
Kyeongjin
K
Schnetkamp
Paul P M
PP
D000818:Animals; D001692:Biological Transport; D017173:Caenorhabditis elegans; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D002645:Chickens; D003001:Cloning, Molecular; D004289:Dolphins; D006801:Humans; D007700:Kinetics; D005810:Multigene Family; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012164:Retinal Diseases / Q000235:genetics*; D017948:Retinal Rod Photoreceptor Cells / Q000502:physiology*; D012374:Rod Cell Outer Segment / Q000502:physiology; D012413:Rubidium / Q000493:pharmacokinetics; D019831:Sodium-Calcium Exchanger / Q000737:chemistry / Q000235:genetics*
D011994:Recombinant Proteins; D019831:Sodium-Calcium Exchanger; C074530:potassium-dependent sodium-calcium exchanger; D012413:Rubidium; D002118:Calcium