Neutral sphingomyelinase 2 (nSMase2) is the primary neutral sphingomyelinase isoform activated by tumour necrosis factor-α in MCF-7 cells.

ABSTRACT: Activation of N-SMase (neutral sphingomyelinase) is an established part of the response of cytokines such as TNF (tumour necrosis factor)-α. However, it remains unclear which of the currently cloned N-SMase isoforms (nSMase1, nSMase2 and nSMase3) are responsible for this activity. In MCF-7 cells, we found that TNF-α induces late, but not early, increases in N-SMase activity, and that nSMase2 is the primary isoform activated, most likely through post-transcriptional mechanisms. Surprisingly, overexpression of tagged or untagged nSMase3 in multiple cell lines had no significant effect on in vitro N-SMase activity. Moreover, only overexpression of nSMase2, but not nSMase1 or nSMase3, had significant effects on cellular sphingolipid levels, increasing ceramide and decreasing sphingomyelin. Add

SUBMITTER: Clarke CJ 

PROVIDER: S-EPMC3715995 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature