Diacylglycerol kinase gamma is a novel anionic phospholipid binding protein with a selective binding preference

作者：Takeshita Ena; Kume Aiko; Maeda Yuki; Sakai Hiromichi; Sakane Fumio^*

来源：Biochemical and Biophysical Research Communications, 2014, 444(4): 617-621.

DOI：10.1016/j.bbrc.2014.01.116

• Diacylglycerol kinase
• Phosphatidic acid
• Ceramide-1-phosphate
• Unsaturated fatty acid
• EF-hand

There are ten isozymes of diacylglycerol kinase (DGK), and they regulate diverse patho-physiological functions. Here, we investigated the lipid-binding properties of DGK isozymes using protein-lipid overlay and liposome-binding assays. DGK gamma showed a strong binding activity compared with other DGK isozymes for phosphatidic acid (PA) among the various glycerophospholipids tested. However, DGK gamma failed to interact with DG and lyso-PA. Moreover, the isozyme was capable of binding to ceramide-l-phosphate but not to ceramide or sphingosine-1-phosphate. The isozyme bound more strongly to PA containing unsaturated fatty acid than to PA having only saturated fatty acid. An analysis using a series of deletion mutants of DGK gamma revealed that the N-terminal region, which contains a recoverin homology domain and EF-hand motifs, is responsible for the PA binding activity of DGK gamma. Taken together, these results indicate that DGK gamma is an anionic phospholipid binding protein that preferably interacts with a small highly charged head group that is very close to the glycerol or sphingosine backbone.

• 出版日期2014-2-21