open access

https://hdl.handle.net/2115/8409

The interaction between the pleckstrin homology domain of ceramide kinase and phosphatidylinositol 4,5-bisphosphate regulates the plasma membrane targeting and ceramide 1-phosphate levels

英語

PI(4,5)P2

2006-04-07

Elsevier

Biochemical and Biophysical Research Communications

342(2)

611-617

Ceramide kinase (CERK) converts ceramide (Cer) to ceramide-1-phosphate (C1P), which has recently emerged as a new bioactive molecule capable of regulating diverse cellular functions. The N-terminus of the CERK protein encompasses a sequence motif known as a pleckstrin homology (PH) domain. Although the PH domain was previously demonstrated to be an important domain for the subcellular localization of CERK, the precise properties of this domain remained unclear. In this study, we reveal that the PH domain of CERK exhibits high affinity for phosphatidylinositol (4,5) bisphosphate (PI(4,5)P2)[0], among other lipids. Furthermore, in COS7 cells, GFPfused CERK translocated rapidly from the cytoplasm to the plasma membrane in response to hyper-osmotic stress, which is known to increase the intracellular PI(4,5)P2 levels, whereas a PH-domain deletion mutant did not. Additionally, in [32P]orthophosphate-labeled COS7 cells, the translocation of CERK to the plasma membrane induced a 2.8 fold increase in C1P levels. The study presented here provides insight into the crucial role of the CERK[0]-PH domain in plasma membrane targeting, through its binding to PI(4,5)P2, and subsequent induction of C1P production in the vicinity of the membrane

学術雑誌論文

Accepted Manuscript

0006-291X

1090-2104