Armadillo repeat-containing protein 1 is a dual localization protein associated with mitochondrial intermembrane space bridging complex

PLoS One. 2019 Oct 23;14(10):e0218303. doi: 10.1371/journal.pone.0218303. eCollection 2019.

Abstract

Cristae architecture is important for the function of mitochondria, the organelles that play the central role in many cellular processes. The mitochondrial contact site and cristae organizing system (MICOS) together with the sorting and assembly machinery (SAM) forms the mitochondrial intermembrane space bridging complex (MIB), a large protein complex present in mammalian mitochondria that partakes in the formation and maintenance of cristae. We report here a new subunit of the mammalian MICOS/MIB complex, an armadillo repeat-containing protein 1 (ArmC1). ArmC1 localizes both to cytosol and mitochondria, where it associates with the outer mitochondrial membrane through its carboxy-terminus. ArmC1 interacts with other constituents of the MICOS/MIB complex and its amounts are reduced upon MICOS/MIB complex depletion. Mitochondria lacking ArmC1 do not show defects in cristae structure, respiration or protein content, but appear fragmented and with reduced motility. ArmC1 represents therefore a peripheral MICOS/MIB component that appears to play a role in mitochondrial distribution in the cell.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Armadillo Domain Proteins / genetics
  • Armadillo Domain Proteins / metabolism*
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Mitochondrial Membranes / metabolism*
  • Mitochondrial Proteins / genetics
  • Mitochondrial Proteins / metabolism*
  • Multiprotein Complexes / genetics
  • Multiprotein Complexes / metabolism*

Substances

  • Armadillo Domain Proteins
  • Mitochondrial Proteins
  • Multiprotein Complexes

Grants and funding

This work was supported by KO3882/1-1 and SFB630 by the Deutsche Forschungsgemeinschaft (https://www.dfg.de/) to VKP. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. This publication was funded by the German Research Foundation (DFG) and the University of Wuerzburg in the funding program Open Access Publishing.