SLP-2 Interacts With Prohibitins in the Mitochondrial Inner Membrane and Contributes to Their Stability

Biochim Biophys Acta. 2008 May;1783(5):904-11. doi: 10.1016/j.bbamcr.2008.02.006. Epub 2008 Feb 20.

Abstract

Stomatin is a member of a large family of proteins including prohibitins, HflK/C, flotillins, mechanoreceptors and plant defense proteins, that are thought to play a role in protein turnover. Using different proteomic approaches, we and others have identified SLP-2, a member of the stomatin gene family, as a component of the mitochondria. In this study, we show that SLP-2 is strongly associated with the mitochondrial inner membrane and that it interacts with prohibitins. Depleting HeLa cells of SLP-2 lead to increased proteolysis of prohibitins and of subunits of the respiratory chain complexes I and IV. Further supporting the role of SLP-2 in regulating the stability of specific mitochondrial proteins, we found that SLP-2 is up-regulated under conditions of mitochondrial stress leading to increased protein turnover. These data indicate that SLP-2 plays a role in regulating the stability of mitochondrial proteins including prohibitins and subunits of respiratory chain complexes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Proteins / metabolism*
  • Cells, Cultured
  • Electron Transport Complex I / metabolism
  • Electron Transport Complex IV / metabolism
  • HeLa Cells
  • Humans
  • Immunoprecipitation
  • Membrane Proteins / metabolism*
  • Mitochondria / metabolism
  • Mitochondrial Membranes / metabolism*
  • Mitochondrial Proteins / metabolism*
  • Repressor Proteins / metabolism*

Substances

  • Blood Proteins
  • Membrane Proteins
  • Mitochondrial Proteins
  • Repressor Proteins
  • STOML2 protein, human
  • prohibitin
  • Electron Transport Complex IV
  • Electron Transport Complex I