Unknown

Dataset Information

0

Cryo-EM structures of fungal and metazoan mitochondrial calcium uniporters.


ABSTRACT: The mitochondrial calcium uniporter (MCU) is a highly selective calcium channel and a major route of calcium entry into mitochondria. How the channel catalyses ion permeation and achieves ion selectivity are not well understood, partly because MCU is thought to have a distinct architecture in comparison to other cellular channels. Here we report cryo-electron microscopy reconstructions of MCU channels from zebrafish and Cyphellophora europaea at 8.5 Å and 3.2 Å resolutions, respectively. In contrast to a previous report of pentameric stoichiometry for MCU, both channels are tetramers. The atomic model of C. europaea MCU shows that a conserved WDXXEP signature sequence forms the selectivity filter, in which calcium ions are arranged in single file. Coiled-coil legs connect the pore to N-terminal domains in the mitochondrial matrix. In C. europaea MCU, the N-terminal domains assemble as a dimer of dimers; in zebrafish MCU, they form an asymmetric crescent. The structures define principles that underlie ion permeation and calcium selectivity in this unusual channel.

SUBMITTER: Baradaran R 

PROVIDER: S-EPMC6336196 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

altmetric image

Publications

Cryo-EM structures of fungal and metazoan mitochondrial calcium uniporters.

Baradaran Rozbeh R   Wang Chongyuan C   Siliciano Andrew Francis AF   Long Stephen Barstow SB  

Nature 20180711 7715


The mitochondrial calcium uniporter (MCU) is a highly selective calcium channel and a major route of calcium entry into mitochondria. How the channel catalyses ion permeation and achieves ion selectivity are not well understood, partly because MCU is thought to have a distinct architecture in comparison to other cellular channels. Here we report cryo-electron microscopy reconstructions of MCU channels from zebrafish and Cyphellophora europaea at 8.5 Å and 3.2 Å resolutions, respectively. In cont  ...[more]

Similar Datasets

| S-EPMC6063787 | biostudies-literature
| S-EPMC6368340 | biostudies-literature
| S-EPMC6155975 | biostudies-literature
| S-EPMC5750132 | biostudies-literature
| S-EPMC6464812 | biostudies-literature
| S-EPMC7439320 | biostudies-literature
| S-EPMC7855493 | biostudies-literature
| S-EPMC9630041 | biostudies-literature
| S-EPMC9977279 | biostudies-literature
| S-EPMC6980868 | biostudies-literature