Mitochondria Maintain Distinct Ca²⁺ Pools in Cone Photoreceptors.

ABSTRACT: Ca²⁺ ions have distinct roles in the outer segment, cell body, and synaptic terminal of photoreceptors. We tested the hypothesis that distinct Ca²⁺ domains are maintained by Ca²⁺ uptake into mitochondria. Serial block face scanning electron microscopy of zebrafish cones revealed that nearly 100 mitochondria cluster at the apical side of the inner segment, directly below the outer segment. The endoplasmic reticulum surrounds the basal and lateral surfaces of this cluster, but does not reach the apical surface or penetrate into the cluster. Using genetically encoded Ca²⁺ sensors, we found that mitochondria take up Ca²⁺ when it accumulates either in the cone cell body or outer segment. Blocking mitochondrial Ca²⁺ uniporter acti

SUBMITTER: Giarmarco MM 

PROVIDER: S-EPMC5338755 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature