Diacylglycerol kinase (DGK or DAGK) is a family of enzymes that catalyzes the conversion of
diacylglycerol (DAG) to
phosphatidic acid (PA), utilizing
ATP as a source of the phosphate.[1] In non-stimulated cells, DGK activity is low, allowing DAG to be used for
glycerophospholipid biosynthesis, but on receptor activation of the
phosphoinositide pathway, DGK activity increases, driving the conversion of DAG to PA. As both lipids are thought to function as bioactive
lipid signaling molecules with distinct cellular targets, DGK therefore occupies an important position, effectively serving as a switch by terminating the signalling of one lipid while simultaneously activating signalling by another.[2]
Currently, nine members of the DGK family have been cloned and identified. Although all family members have conserved catalytic domains and two
cysteine rich domains, they are further classified into five groups according to the presence of additional functional domains and substrate specificity.[5] These are as follows:
Type 1 - DGK-α, DGK-β, DGK-γ - contain
EF-hand motifs and a
recoverin homology domain
Type 5 - DGK-θ - contains a third cysteine-rich domain, a pleckstrin homology domain and a proline rich region
References
^Shulga, Yulia V.; Topham, Matthew K.; Epand, Richard M. (2011). "Regulation and Functions of Diacylglycerol Kinases". Chemical Reviews. 111 (10): 6186–6208.
doi:
10.1021/cr1004106.
PMID21800853.
^Mérida I, Avila-Flores A, Merino E (January 2008). "Diacylglycerol kinases: at the hub of cell signalling". The Biochemical Journal. 409 (1): 1–18.
doi:
10.1042/BJ20071040.
PMID18062770.
