RRC ID 72290
Author Shindo M, Irie K, Ohigashi H, Kuriyama M, Saito N.
Title Diacylglycerol kinase gamma is one of the specific receptors of tumor-promoting phorbol esters.
Journal Biochem Biophys Res Commun
Abstract Diacylglycerol kinase (DGK) and protein kinase C (PKC) are two different enzyme families that interact with diacylglycerol. Both enzymes contain cysteine-rich C1 domains with a zinc finger-like structure. Most of the C1 domains of PKCs show strong phorbol-12,13-dibutyrate (PDBu) binding with nanomolar dissociation constants (K(d)'s). However, there has been no experimental evidence that phorbol esters bind to the C1 domains of DGKs. We focused on DGK gamma because its C1A domain has a high degree of sequence homology to those of PKCs, and because DGK gamma translocates from the cytoplasm to the plasma membrane following 12-O-tetradecanoylphorbol-13-acetate treatment similar to PKCs. Two C1 domains of DGK gamma (DGK gamma-C1A and DGK gamma-C1B) were synthesized and tested for their PDBu binding along with whole DGK gamma (Flag-DGK gamma) expressed in COS-7 cells. DGK gamma-C1A and Flag-DGK gamma showed strong PDBu binding affinity, while DGK gamma-C1B was completely inactive. Scatchard analysis of DGK gamma-C1A and Flag-DGK gamma gave K(d)'s of 3.1 and 4.4 nM, respectively, indicating that the major PDBu binding site of DGK gamma is C1A. This is the first evidence that DGK gamma is a specific receptor of tumor-promoting phorbol esters.
Volume 289(2)
Pages 451-6
Published 2001-11-30
DOI 10.1006/bbrc.2001.5935
PII S0006-291X(01)95935-2
PMID 11716494
MeSH Amino Acid Sequence Animals CHO Cells COS Cells Cell Membrane / enzymology Cricetinae Cytoplasm / enzymology Diacylglycerol Kinase / metabolism* Dose-Response Relationship, Drug Kinetics Models, Genetic Molecular Sequence Data Mutation Peptides / chemistry Phorbol Esters / metabolism* Plasmids / metabolism Protein Binding Protein Structure, Tertiary Protein Transport Sequence Homology, Amino Acid Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization Spectrophotometry Tetradecanoylphorbol Acetate / pharmacology Zinc Fingers
Human and Animal Cells COS-7(RCB0539)