14-3-3 Proteins in the regulation of rotenone-induced neurotoxicity might be via its isoform 14-3-3epsilon's involvement in autophagy

Cell Mol Neurobiol. 2013 Nov;33(8):1109-21. doi: 10.1007/s10571-013-9977-9. Epub 2013 Sep 4.

Abstract

14-3-3 proteins have been confirmed to be involved in Parkinson's disease. It has been reported that an increase of 14-3-3 (theta, epsilon, and gamma) expression has neuroprotective effect in response to rotenone and MPP(+) in dopaminergic cell culture and transgenic C. elegans with alpha-synuclein overexpression. To further investigate the detail mechanism of 14-3-3 proteins in rotenone-induced dopamine neurotoxicity, we observed the expression of 14-3-3 isoforms, and the influence of 14-3-3epsilon knockdown on autophagic activity and cell function. The results showed that rotenone led to a decrease in expression of 14-3-3 protein and mRNA, and an increase in expression and aggregation of alpha-synuclein protein. Knockdown of 14-3-3epsilon expression in turn further aggravated PC12 cell damage, such as an enhancement of ROS formation, and a reduction of cell viability and ATP production. Further experiments confirmed that the autophagic activity was promoted with 14-3-3epsilon siRNA transfection, including an enhancement of autophagosome formation and the ratio of LC3-II/LC3-I. Therefore, we concluded that the regulation of 14-3-3 proteins in rotenone-induced neurotoxicity might be associated with its isoform 14-3-3epsilon's involvement in autophagy, which might be considered a mechanism in addition to the currently known function of 14-3-3 proteins in neurodegenerative disease pathogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 14-3-3 Proteins / genetics
  • 14-3-3 Proteins / metabolism*
  • Adenosine Triphosphate / metabolism
  • Animals
  • Autophagy / drug effects*
  • Autophagy / genetics
  • Cell Shape / drug effects
  • Cell Shape / genetics
  • Cell Survival / drug effects
  • Cell Survival / genetics
  • Gene Expression Regulation / drug effects
  • Microtubule-Associated Proteins / metabolism
  • Neurotoxins / toxicity*
  • PC12 Cells
  • Phagosomes / drug effects
  • Phagosomes / metabolism
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Protein Structure, Quaternary
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Small Interfering / metabolism
  • Rats
  • Reactive Oxygen Species / metabolism
  • Rotenone / toxicity*
  • Transfection
  • alpha-Synuclein / metabolism

Substances

  • 14-3-3 Proteins
  • LC3 protein, rat
  • Microtubule-Associated Proteins
  • Neurotoxins
  • Protein Isoforms
  • RNA, Messenger
  • RNA, Small Interfering
  • Reactive Oxygen Species
  • alpha-Synuclein
  • Rotenone
  • Adenosine Triphosphate