Send to

Choose Destination
See comment in PubMed Commons below
Biochem J. 2009 Nov 11;424(2):273-83. doi: 10.1042/BJ20090699.

Disruption of ceramide synthesis by CerS2 down-regulation leads to autophagy and the unfolded protein response.

Author information

  • 1Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA.


Ceramide metabolism has come under recent scrutiny because of its role in cellular stress responses. CerS2 (ceramide synthase 2) is one of the six mammalian isoforms of ceramide synthase and is responsible for the synthesis of VLC (very-long-chain) ceramides, e.g. C24, C24:1. To study the role of CerS2 in ceramide metabolism and cellular homoeostasis, we down-regulated CerS2 using siRNA (small interfering RNA) and examined several aspects of sphingolipid metabolism and cell stress responses. CerS2 down-regulation had a broad effect on ceramide homoeostasis, not just on VLC ceramides. Surprisingly, CerS2 down-regulation resulted in significantly increased LC (long-chain) ceramides, e.g. C14, C16, and our results suggested that the increase was due to a ceramide synthase-independent mechanism. CerS2-down-regulation-induced LC ceramide accumulation resulted in growth arrest which was not accompanied by apoptotic cell death. Instead, cells remained viable, showing induction of autophagy and activation of PERK [PKR (double-stranded-RNA-dependent protein kinase)-like endoplasmic reticulum kinase] and IRE1 (inositol-requiring 1) pathways [the latter indicating activation of the UPR (unfolded protein response)].

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center