Skip to Content
Merck
  • Osmotic shock-dependent redistribution of diacylglycerol kinase η1 to non-ionic detergent-resistant membrane via pleckstrin homology and C1 domains.

Osmotic shock-dependent redistribution of diacylglycerol kinase η1 to non-ionic detergent-resistant membrane via pleckstrin homology and C1 domains.

Journal of biochemistry (2012-11-07)
Daisuke Matsutomo, Takeshi Isozaki, Hiromichi Sakai, Fumio Sakane
ABSTRACT

Diacylglycerol kinase (DGK) participates in regulating the intracellular concentrations of two bioactive lipids, diacylglycerol and phosphatidic acid. DGKη1 is a type II isozyme that contains a pleckstrin homology (PH) domain and a pair of C1 domains at the N-terminus and separated catalytic domains (catalytic subdomain-a and b). We previously reported that DGKη1 expressed in COS-7 cells is translocated from the cytoplasm to punctate granules that partially include endosomes in response to stress stimuli such as osmotic shock. However, the biochemical properties of the stress-dependent behaviour of DGKη1 remain unknown. Here, we have found that DGKη1 is redistributed from the cytosol to the non-ionic detergent (Nonidet P-40)-resistant membrane (DRM) in response to osmotic shock. Our results strongly suggested that the Nonidet P-40 insolubility of DGKη1 is due to neither cytoskeleton localization nor lipid raft association, implying that DGKη1 is distributed to detergent-resistant membrane microdomains that have a low lipid-to-protein ratio. We revealed, using a series of DGKη1 deletion mutants, that the PH and C1 domains play a pivotal role in osmotic shock-dependent DRM redistribution, whereas catalytic subdomain-a negatively regulates the event.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Poly(vinylidene fluoride), average Mw ~180,000 by GPC, average Mn ~71,000, beads or pellets
Sigma-Aldrich
Poly(vinylidene fluoride), average Mw ~275,000 by GPC, average Mn ~107,000, pellets
Sigma-Aldrich
Poly(vinylidene fluoride), average Mw ~530,000, pellets
Sigma-Aldrich
Poly(vinylidene fluoride), average Mw ~534,000 by GPC, powder