Spen modulates lipid droplet content in adult Drosophila glial cells and protects against paraquat toxicity

Sci Rep. 2020 Nov 18;10(1):20023. doi: 10.1038/s41598-020-76891-9.

Abstract

Glial cells are early sensors of neuronal injury and can store lipids in lipid droplets under oxidative stress conditions. Here, we investigated the functions of the RNA-binding protein, SPEN/SHARP, in the context of Parkinson's disease (PD). Using a data-mining approach, we found that SPEN/SHARP is one of many astrocyte-expressed genes that are significantly differentially expressed in the substantia nigra of PD patients compared with control subjects. Interestingly, the differentially expressed genes are enriched in lipid metabolism-associated genes. In a Drosophila model of PD, we observed that flies carrying a loss-of-function allele of the ortholog split-ends (spen) or with glial cell-specific, but not neuronal-specific, spen knockdown were more sensitive to paraquat intoxication, indicating a protective role for Spen in glial cells. We also found that Spen is a positive regulator of Notch signaling in adult Drosophila glial cells. Moreover, Spen was required to limit abnormal accumulation of lipid droplets in glial cells in a manner independent of its regulation of Notch signaling. Taken together, our results demonstrate that Spen regulates lipid metabolism and storage in glial cells and contributes to glial cell-mediated neuroprotection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / drug effects
  • Drosophila melanogaster / growth & development*
  • Drosophila melanogaster / metabolism
  • Gene Expression Regulation, Developmental*
  • Herbicides / toxicity
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • Lipid Droplets / chemistry*
  • Male
  • Neuroglia / cytology*
  • Neuroglia / drug effects
  • Neuroglia / metabolism
  • Paraquat / toxicity*
  • Parkinson Disease / etiology
  • Parkinson Disease / metabolism
  • Parkinson Disease / pathology
  • Parkinson Disease / prevention & control*
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism*

Substances

  • Drosophila Proteins
  • Herbicides
  • Homeodomain Proteins
  • RNA-Binding Proteins
  • Spen protein, Drosophila
  • Paraquat