The Na+/Ca2+, K+ exchanger NCKX4 is required for efficient cone-mediated vision

Frans Vinberg, Tian Wang, Alicia De Maria, Haiqing Zhao, Steven Bassnett, Jeannie Chen, Vladimir J. Kefalov

Research output: Contribution to journalArticle

13 Scopus citations

Abstract

Calcium (Ca2+) plays an important role in the function and health of neurons. In vertebrate cone photoreceptors, Ca2+ controls photoresponse sensitivity, kinetics, and light adaptation. Despite the critical role of Ca2+ in supporting the function and survival of cones, the mechanism for its extrusion from cone outer segments is not well understood. Here, we show that the Na+/Ca2+, K+ exchanger NCKX4 is expressed in zebrafish, mouse, and primate cones. Functional analysis of NCKX4-deficient mouse cones revealed that this exchanger is essential for the wide operating range and high temporal resolution of cone-mediated vision. We show that NCKX4 shapes the cone photoresponse together with the cone-specific NCKX2: NCKX4 acts early to limit response amplitude, while NCKX2 acts late to further accelerate response recovery. The regulation of Ca2+ by NCKX4 in cones is a novel mechanism that supports their ability to function as daytime photoreceptors and promotes their survival.

Original languageEnglish
Article numbere24550
JournaleLife
Volume6
DOIs
StatePublished - Jun 26 2017

Fingerprint Dive into the research topics of 'The Na<sup>+</sup>/Ca<sup>2+</sup>, K<sup>+</sup> exchanger NCKX4 is required for efficient cone-mediated vision'. Together they form a unique fingerprint.

  • Cite this