A plant nucleoside diphosphate kinase homologous to the human Nm23 gene product: purification and characterization.
Nucleoside diphosphate kinases (NDPKs) catalyze the transfer of high-energy phosphates from nucleoside triphosphates to nucleoside diphosphates and may be involved in the regulation of growth, development, and signal transduction processes. We report here the purification and characterization of NDPK from detergent-solubilized extracts of dark-grown oat (Avena) tissue. The purification was achieved primarily through adsorption to GTP-agarose, followed by elution with ATP. SDS-polyacrylamide gel electrophoresis and gel filtration chromatography indicated that the purified protein is composed of six 18 kDa subunits. Substrate specificity experiments indicated that the purified kinase is capable of using all tested nucleosides as substrates. N-terminal sequencing of the Avena protein revealed that 87% of the 23 amino acids sequenced were identical to the human Nm23 protein, a nucleoside diphosphate kinase identified as a possible tumor metastasis suppressor and transcriptional activator of the myc oncogene.
Department of Chemistry, University of Nebraska-Lincoln 68588-0304.
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D000595:Amino Acid Sequence; D007700:Kinetics; D008969:Molecular Sequence Data; D020559:Monomeric GTP-Binding Proteins; D054778:NM23 Nucleoside Diphosphate Kinases; D009701:Nucleoside-Diphosphate Kinase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D010940:Plant Proteins / Q000235:genetics / Q000302:isolation & purification*; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics*
D054778:NM23 Nucleoside Diphosphate Kinases; D010940:Plant Proteins; D014157:Transcription Factors; C517938:NME1 protein, human; D009701:Nucleoside-Diphosphate Kinase; D020559:Monomeric GTP-Binding Proteins