Phosphorylation of delta sleep-inducing peptide (DSIP) by casein kinase II in vitro.
A phosphorylated analogue of DSIP at Ser7 has been shown to exist endogenously by immunochemical studies. An enzyme which could phosphorylate DSIP has not yet been identified. In the present study, we examined DSIP as a substrate for in vitro phosphorylation by casein kinase II. DSIP was phosphorylated by the enzyme with apparent Km and Vmax values of 20 mM and 90.9 nmol/min/mg protein, respectively. Both ATP and GTP were utilized as phosphoryl donors. Phosphorylation of DSIP was inhibited by heparin and enhanced by spermine. These results demonstrate that DSIP can serve as a possible substrate for casein kinase II in vitro.
Nakamura
A
A
Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Japan.
Shiomi
H
H
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D047388:Casein Kinases; D003701:Delta Sleep-Inducing Peptide / Q000737:chemistry / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D011817:Rabbits; D013379:Substrate Specificity
D009842:Oligopeptides; D003701:Delta Sleep-Inducing Peptide; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D011494:Protein Kinases; D047388:Casein Kinases