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MICU1 Interacts with the D-Ring of the MCU Pore to Control Its Ca2+ Flux and Sensitivity to Ru360.

ABSTRACT: Proper control of the mitochondrial Ca2+ uniporter's pore (MCU) is required to allow Ca2+-dependent activation of oxidative metabolism and to avoid mitochondrial Ca2+ overload and cell death. The MCU's gatekeeping and cooperative activation is mediated by the Ca2+-sensing MICU1 protein, which has been proposed to form dimeric complexes anchored to the EMRE scaffold of MCU. We unexpectedly find that MICU1 suppresses inhibition of MCU by ruthenium red/Ru360, which bind to MCU's DIME motif, the selectivity filter. This led us to recognize in MICU1's sequence a putative DIME interacting domain (DID), which is required for both gatekeeping and cooperative activation of MCU and for cell survival. Thus, we propose that MICU1 has to interact with the D-ring formed by the DIME domains in MCU to control the uniporter.

SUBMITTER: Paillard M

PROVIDER: S-EPMC6251499 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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MICU1 Interacts with the D-Ring of the MCU Pore to Control Its Ca2+ Flux and Sensitivity to Ru360.

Paillard Melanie M Csordás György G Huang Kai-Ting KT Várnai Peter P Joseph Suresh K SK Hajnóczky György G

Molecular cell 20181025 4

Proper control of the mitochondrial Ca2+ uniporter's pore (MCU) is required to allow Ca2+-dependent activation of oxidative metabolism and to avoid mitochondrial Ca2+ overload and cell death. The MCU's gatekeeping and cooperative activation is mediated by the Ca2+-sensing MICU1 protein, which has been proposed to form dimeric complexes anchored to the EMRE scaffold of MCU. We unexpectedly find that MICU1 suppresses inhibition of MCU by ruthenium red/Ru ...[more]

PMID: 30454562

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