New role for EMD (emerin), a key inner nuclear membrane protein, as an enhancer of autophagosome formation in the C16-ceramide autophagy pathway

Abstract

To date, precise roles of EMD (emerin) remain poorly described. In this paper, we investigated the role of EMD in the C16-ceramide autophagy pathway. Ceramides are bioactive signaling molecules acting notably in the regulation of cell growth, differentiation, or cell death. However, the mechanisms by which they mediate these pathways are not fully understood. We found that C16-ceramide induces EMD phosphorylation on its LEM domain through PRKACA. Upon ceramide treatment, phosphorylated EMD binds MAP1LC3B leading to an increase of autophagosome formation. These data suggest a new role of EMD as an enhancer of autophagosome formation in the C16-ceramide autophagy pathway in colon cancer cells.

Keywords: :

• autophagy
• ceramide
• colon cancer cells
• EMD
• LEM-domain
• phosphorylation
• PRKACA

Disclosure of Potential Conflicts of Interest

No potential conflicts of interest were disclosed.

Acknowledgments

MP Merville is a senior research associate at the National Fund for Scientific Research (FR-FNRS), Belgium. This work was financially supported by ARC fund and Léon Frédéricq grant from University of Liège. We thank the “Imaging Platform” (S Ormenese and G Moraes, GIGA, University of Liège) for the confocal imaging and the “Viral vector platform” (E Divalentin, GIGA, University of Liège) for stable cell lines generation.