Suppression of Mic60 compromises mitochondrial transcription and oxidative phosphorylation

Sci Rep. 2015 Jan 23:5:7990. doi: 10.1038/srep07990.

Abstract

Precise regulation of mtDNA transcription and oxidative phosphorylation (OXPHOS) is crucial for human health. As a component of mitochondrial contact site and cristae organizing system (MICOS), Mic60 plays a central role in mitochondrial morphology. However, it remains unclear whether Mic60 affects mitochondrial transcription. Here, we report that Mic60 interacts with mitochondrial transcription factors TFAM and TFB2M. Furthermore, we found that Mic60 knockdown compromises mitochondrial transcription and OXPHOS activities. Importantly, Mic60 deficiency decreased TFAM binding and mitochondrial RNA polymerase (POLRMT) recruitment to the mtDNA promoters. In addition, through mtDNA immunoprecipitation (mIP)-chromatin conformation capture (3C) assays, we found that Mic60 interacted with mtDNA and was involved in the architecture of mtDNA D-loop region. Taken together, our findings reveal a previously unrecognized important role of Mic60 in mtDNA transcription.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • DNA, Mitochondrial
  • DNA-Binding Proteins / metabolism
  • Gene Knockdown Techniques
  • Humans
  • Methyltransferases / metabolism
  • Mitochondria / genetics*
  • Mitochondria / metabolism*
  • Mitochondrial Proteins / genetics
  • Mitochondrial Proteins / metabolism*
  • Muscle Proteins / genetics
  • Muscle Proteins / metabolism*
  • Oxidative Phosphorylation*
  • Promoter Regions, Genetic
  • Protein Binding
  • Transcription Factors / metabolism
  • Transcription, Genetic*

Substances

  • DNA, Mitochondrial
  • DNA-Binding Proteins
  • IMMT protein, human
  • Mitochondrial Proteins
  • Muscle Proteins
  • TFAM protein, human
  • Transcription Factors
  • Methyltransferases
  • TFB2M protein, human