The crystal structure of MICU2 provides insight into Ca²⁺ binding and MICU1-MICU2 heterodimer formation.

ABSTRACT: The mitochondrial calcium uniporter (MCU) complex mediates the uptake of Ca²⁺ into mitochondria. Its activity is regulated by a heterodimer of MICU1 and MICU2, two EF-hand-containing proteins that act as the main gatekeeper of the uniporter. Herein we report the crystal structure of human MICU2 at 1.96 Å resolution. Our structure reveals a dimeric architecture of MICU2, in which each monomer adopts the canonical two-lobe structure with a pair of EF-hands in each lobe. Both Ca²⁺ -bound and Ca²⁺ -free EF-hands are observed in our structure. Moreover, we characterize the interaction sites within the MICU2 homodimer, as well as the MICU1-MICU2 heterodimer in both Ca²⁺ -free and Ca²⁺ -bound conditions. Glu242 in MICU1 and Arg352 in MICU2 ar

SUBMITTER: Wu W 

PROVIDER: S-EPMC6726906 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature