title: Purification, activity, and expression levels of two uridine-cytidine kinase isoforms in neuroblastoma cell lines.
abstract: Uridine-cytidine kinase (UCK) catalyzes the phosphorylation of uridine, cytidine, and several pyrimidine ribonucleoside analogs. We overexpressed and purified the two known isoforms of human UCK in Escherichia coli, produced a specific antibody against UCK1 and characterized the kinetic properties of UCK1 and 2. The Vmaxof purified recombinant UCK2 was 22- and 8-fold higher with uridine and cytidine, respectively, compared to those observed for the purified recombinant UCK1 enzyme. The Kmof UCK1 was 39- and 40-fold higher with uridine and cytidine, respectively, compared to those observed for the purified recombinant UCK2 enzyme. The UCK1 antibody showed no cross reactivity against UCK2. Our data showed that UCK1 and 2 are both expressed in several neuroblastoma cell lines, including four MYCN single copy cell lines and five MYCN amplified cell lines, with the exception that UCK1 was not expressed in SJNB8. These results indicate that UCK2 in neuroblastoma might be used as a selective target for chemotherapy using UCK2-dependent pyrimidine analogues.
authors.affiliation: a Academic Medical Center, Laboratory Genetic Metabolic Diseases , Amsterdam , The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Meinsma
authors.affiliation: a Academic Medical Center, Laboratory Genetic Metabolic Diseases , Amsterdam , The Netherlands.
authors.forename: A B P
authors.initials: AB
authors.lastname: van Kuilenburg
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry; D003562:Cytidine / Q000737:chemistry; D004926:Escherichia coli; D015870:Gene Expression; D006801:Humans; D007700:Kinetics; D009447:Neuroblastoma / Q000201:enzymology; D009703:Nucleoside-Phosphate Kinase / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D013379:Substrate Specificity; D014529:Uridine / Q000737:chemistry; D014541:Uridine Kinase / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*
chemical_list: D003562:Cytidine; D000255:Adenosine Triphosphate; C483834:UCK2 protein, human; D014541:Uridine Kinase; C019979:cytidylate kinase; D009703:Nucleoside-Phosphate Kinase; D014529:Uridine
keywords: Enzymology; anticancer nucleosides; nucleoside and nucleotide kinases