Interactomic study on interaction between lipid droplets and mitochondria

Protein Cell. 2011 Jun;2(6):487-96. doi: 10.1007/s13238-011-1061-y. Epub 2011 Jul 12.

Abstract

An increasing body of evidence shows that the lipid droplet, a neutral lipid storage organelle, plays a role in lipid metabolism and energy homeostasis through its interaction with mitochondria. However, the cellular functions and molecular mechanisms of the interaction remain ambiguous. Here we present data from transmission electron microscopy, fluorescence imaging, and reconstitution assays, demonstrating that lipid droplets physically contact mitochondria in vivo and in vitro. Using a bimolecular fluorescence complementation assay in Saccharomyces cerevisiae, we generated an interactomic map of protein-protein contacts of lipid droplets with mitochondria and peroxisomes. The lipid droplet proteins Erg6 and Pet10 were found to be involved in 75% of the interactions detected. Interestingly, interactions between 3 pairs of lipid metabolic enzymes were detected. Collectively, these data demonstrate that lipid droplets make physical contacts with mitochondria and peroxisomes, and reveal specific molecular interactions that suggest active participation of lipid droplets in lipid metabolism in yeast.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Genetic Complementation Test
  • Lipid Metabolism*
  • Lipids
  • Microscopy, Electron, Transmission
  • Microscopy, Fluorescence
  • Mitochondria / metabolism*
  • Muscle Cells / metabolism*
  • Muscle, Skeletal / cytology
  • Muscle, Skeletal / metabolism*
  • Oncogene Proteins / genetics
  • Oncogene Proteins / metabolism*
  • Peroxisomes / metabolism
  • Plasmids
  • Protein Binding
  • Protein Interaction Mapping* / methods
  • Rats
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism*
  • Saccharomyces cerevisiae
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Transformation, Genetic

Substances

  • Lipids
  • Oncogene Proteins
  • Recombinant Fusion Proteins
  • Transcription Factors