title: Distinct 1-monoacylglycerol and 2-monoacylglycerol kinase activities of diacylglycerol kinase isozymes.
abstract: Diacylglycerol kinase (DGK) consists of ten isozymes and is involved in a wide variety of patho-physiological events. However, the enzymological properties of DGKs have not been fully understood. In this study, we performed a comprehensive analysis on the 1-monoacylglycerol kinase (MGK) and 2-MGK activities of ten DGK isozymes. We revealed that type I (α, β and γ), type II (δ, η and κ) and type III (ε) DGKs have 7.9-19.2% 2-MGK activity compared to their DGK activities, whereas their 1-MGK activities were <3.0%. Both the 1-MGK and 2-MGK activities of the type IV DGKs (ζ and ι) were <1% relative to their DGK activities. Intriguingly, type V DGKθ has approximately 6% 1-MGK activity and <2% 2-MGK activity compared to its DGK activity. Purified DGKθ exhibited the same results, indicating that its 1-MGK activity is intrinsic. Therefore, DGK isozymes are categorized into three types with respect to their 1-MGK and 2-MGK activities: those having (1) 2-MGK activity relatively stronger than their 1-MGK activity (types I-III), (2) only negligible 1-MGK and 2-MGK activities (type IV), and (3) 1-MGK activity stronger than its 2-MGK activity (type V). The 1-MGK activity of DGKθ and the 2-MGK activity of DGKα were stronger than those of the acylglycerol kinase reported as 1-MGK and 2-MGK to date. The presence or absence of 1-MGK and 2-MGK activities may be essential to the patho-physiological functions of each DGK isozyme.
authors.affiliation: Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Murakami
authors.affiliation: Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Atsumi
authors.initials: A
authors.lastname: Yamaki
authors.affiliation: Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Mizuno
authors.affiliation: Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Sakai
authors.affiliation: Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan. Electronic address: sakane@faculty.chiba-u.jp.
authors.forename: Fumio
authors.initials: F
authors.lastname: Sakane
mesh_terms: D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D019852:Diacylglycerol Kinase / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D004075:Diglycerides / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D007527:Isoenzymes / Q000145:classification / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D051379:Mice; D050178:Monoglycerides / Q000378:metabolism*; D010766:Phosphorylation; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity; D013552:Swine
chemical_list: D004075:Diglycerides; D007527:Isoenzymes; D050178:Monoglycerides; D011993:Recombinant Fusion Proteins; D017853:Phosphotransferases (Alcohol Group Acceptor); D019852:Diacylglycerol Kinase; C025944:acylglycerol kinase
keywords: Diacylglycerol kinase; Lysophosphatidic acid; Monoacylglycerol kinase; Phosphatidic acid