Evidence that mono-ADP-ribosylation of CtBP1/BARS regulates lipid storage

René Bartz, Joachim Seemann, John K. Zehmer, Ginette Serrero, Kent D. Chapman, Richard G W Anderson, Pingsheng Liu

Research output: Contribution to journalArticle

23 Scopus citations

Abstract

Mono-ADP-ribosylation is emerging as an important posttranslational modification that modulates a variety of cell signaling pathways. Here, we present evidence that mono-ADP-ribosylation of the transcriptional corepressor C terminal binding protein, brefeldin A (BFA)-induced ADP-ribosylated substrate (CtBP1/BARS) regulates neutral lipid storage in droplets that are surrounded by a monolayer of phospholipid and associated proteins. CtBP1/BARS is an NAD-binding protein that becomes ribosylated when cells are exposed to BFA. Both endogenous lipid droplets and droplets enlarged by oleate treatment are lost after 12-h exposure to BFA. Lipid loss requires new protein synthesis, and it is blocked by multiple ribosylation inhibitors, but it is not stimulated by disruption of the Golgi apparatus or the endoplasmic reticulum unfolded protein response. Small interfering RNA knockdown of CtBP1/BARS mimics the effect of BFA, and mouse embryonic fibroblasts derived from embryos that are deficient in CtBP1/BARS seem to be defective in lipid accumulation. We conclude that mono-ADP-ribosylation of CtBP1/BARS inactivates its repressor function, which leads to the activation of genes that regulate neutral lipid storage.

Original languageEnglish (US)
Pages (from-to)3015-3025
Number of pages11
JournalMolecular biology of the cell
Volume18
Issue number8
DOIs
StatePublished - Aug 1 2007

    Fingerprint

ASJC Scopus subject areas

  • Molecular Biology
  • Cell Biology

Cite this

Bartz, R., Seemann, J., Zehmer, J. K., Serrero, G., Chapman, K. D., Anderson, R. G. W., & Liu, P. (2007). Evidence that mono-ADP-ribosylation of CtBP1/BARS regulates lipid storage. Molecular biology of the cell, 18(8), 3015-3025. https://doi.org/10.1091/mbc.E06-09-0869