title: The primase activity of DNA polymerase alpha from calf thymus.
abstract: The nearly homogeneous 9 S DNA polymerase alpha from calf thymus contains a primase activity that allows priming of DNA synthesis on single-stranded templates in the presence of ribonucleoside triphosphates. Both on synthetic and natural single-stranded templates, RNA primers of 8-15 nucleotides in length are formed. In the absence of dNTPs, primers of some hundred nucleotides in length are observable. ATP and/or GTP are required for the priming reaction. UTP and CTP cannot initiate the RNA synthesis. M13 single-stranded DNA can be converted to the nicked double helical form upon primase-primed replication by the 9 S enzyme. Priming occurs mostly at specific sites on the M13 genome and replication products of up to 6000 nucleotides in length are formed. In the presence of the single-stranded DNA binding protein from Escherichia coli, specificity of priming is strongly increased. The primase is inhibited by salt and actinomycin; it is insensitive to alpha-amanitin and N-ethylmaleimide. Due to the strong complex formation between DNA polymerase and primase, it has not been possible to separate the two activities of the multisubunit 9 S enzyme.
authors.forename: F
authors.initials: F
authors.lastname: Grosse
authors.forename: G
authors.initials: G
authors.lastname: Krauss
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D004247:DNA / Q000096:biosynthesis; D004257:DNA Polymerase II / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D019915:DNA Primase; D004277:DNA, Single-Stranded / Q000096:biosynthesis; D004268:DNA-Binding Proteins / Q000494:pharmacology; D003854:Deoxyribonucleotides / Q000378:metabolism; D009843:Oligoribonucleotides / Q000378:metabolism; D012313:RNA / Q000096:biosynthesis; D012316:RNA Nucleotidyltransferases / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D012265:Ribonucleotides / Q000378:metabolism; D013379:Substrate Specificity; D013698:Templates, Genetic; D013873:Thionucleotides / Q000378:metabolism; D013950:Thymus Gland / Q000201:enzymology*
chemical_list: D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D003854:Deoxyribonucleotides; D009843:Oligoribonucleotides; D012265:Ribonucleotides; D013873:Thionucleotides; C022571:adenosine 5'-O-(3-thiotriphosphate); D012313:RNA; D000255:Adenosine Triphosphate; D004247:DNA; D019915:DNA Primase; D012316:RNA Nucleotidyltransferases; D004257:DNA Polymerase II