Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1996-5-17
pubmed:abstractText
In mammalian cells DNA synthesis is more complicated than in prokaryotes and less well understood. Here we incubated intact mammalian cells (polyamine auxotrophic Chinese hamster ovary cells and primary human fibroblasts) with [32P]orthophosphate and found that, besides high molecular weight DNA, a species of low molecular weight DNA, approximately 450 bp in size, became efficiently labeled. The short DNA was labeled first, and in pulse-chase experiments the labeling was transient. The isolated small DNA fragments (RNase A-treated) were phosphorylated by T4 polynucleotide kinase specific for polynucleotides with 5'-OH ends. A polynucleotide kinase phosphorylating these DNA pieces was also detected in nuclear extracts of the cells. Treatment with alkaline phosphatase removed most of the 32P label incorporated into the small DNA in vivo. Labeling with deoxyribonucleosides did not reveal these fragments. We hypothesize that the low molecular weight DNA represents Okazaki fragments and that the mammalian DNA replication machinery includes a polynucleotide kinase phosphorylating the 5'-termini of Okazaki fragments. This would imply a novel step in DNA synthesis. We also show that depriving cells of polyamines reversibly blocks synthesis of high molecular weight DNA and leads to accumulation of the short DNA pieces, suggesting a role for polyamines in joining the Okazaki fragments.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-1231932, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-2115438, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-2122233, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-2165567, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-2393905, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-3006761, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-3386630, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-3504, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-3722208, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-4033657, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-6206782, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-6250445, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-6250448, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-6860671, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-7910375, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-7988294, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-8144677, http://linkedlifedata.com/resource/pubmed/commentcorrection/8605890-8352592
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0261-4189
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1193-200
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Phosphorylation of Okazaki-like DNA fragments in mammalian cells and role of polyamines in the processing of this DNA.
pubmed:affiliation
Department of Virology, University of Helsinki, Finland.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't