title: Purification and characterization of the double-stranded DNA-activated protein kinase, DNA-PK, from human placenta.
abstract: The double-stranded DNA-activated protein kinase (DNA-PK) is a serine-threonine protein kinase that is composed of a large catalytic subunit (p350) and a DNA-binding protein of 70 and 80 kDa subunits known as the Ku autoantigen. When targeted to DNA by free DNA ends, DNA-PK phosphorylates many DNA-binding proteins and transcription factors. Previously, DNA-PK had only been purified and characterized from transformed human tissue culture cells. Here we report that DNA-PK is an abundant protein in human placenta and lymphocytes. We have purified the placental DNA-PK to homogeneity and show that its biochemical properties are similar to those of the HeLa cell enzyme.
authors.affiliation: Department of Biological Sciences, University of Calgary, Canada.
authors.forename: D W
authors.initials: DW
authors.lastname: Chan
authors.forename: C H
authors.initials: CH
authors.lastname: Mody
authors.forename: N S
authors.initials: NS
authors.lastname: Ting
authors.forename: S P
authors.initials: SP
authors.lastname: Lees-Miller
mesh_terms: D015153:Blotting, Western; D002847:Chromatography, Agarose; D002853:Chromatography, Liquid; D051747:DNA-Activated Protein Kinase; D004268:DNA-Binding Proteins; D011756:Diphosphates / Q000494:pharmacology; D006801:Humans; D008214:Lymphocytes / Q000201:enzymology; D009687:Nuclear Proteins; D010766:Phosphorylation; D010920:Placenta / Q000201:enzymology*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D004268:DNA-Binding Proteins; D011756:Diphosphates; D009687:Nuclear Proteins; D051747:DNA-Activated Protein Kinase; C497263:PRKDC protein, human; D017346:Protein Serine-Threonine Kinases