Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1984-11-14
pubmed:abstractText
An in vitro model system including wild-type T4 DNA polymerase, the mutagenic nucleotide analogue 2-aminopurine deoxyribonucleoside triphosphate, and poly[d(A,C)] X oligo(dT) poly(dC) X oligo(dG) template-primers is used to measure the frequency of 2-aminopurine X cytosine base mispairs formed in the G X C----A X T mutational pathway. Incorporation and turnover of the analogue into DNA is dependent on the presence of cytosine on the template strand and is reduced significantly in the presence of dGTP. 2-Aminopurine X cytosine mispairs are observed to occur at a 2-3 order of magnitude greater frequency than adenine X cytosine mispairs. The frequency of inserting 2-aminopurine deoxyribonucleoside monophosphate in place of dGMP opposite template cytosine sites is about 3-6% when either strong or weak base-stacking partners are present on the primer strand. However, enzymatic proofreading of the mispair strongly depends on base-stacking partners. Greater than 85% of misinserted 2-aminopurine deoxynucleotides are excised whenever the mispairs are formed next to 5'-primer thymine sites. A 5-fold reduction in proofreading frequency occurs when the mispair is formed with 2-aminopurine deoxynucleoside monophosphate stacked adjacent to a 5'-primer guanine. The frequency of 2-aminopurine X cytosine base mispair formation in the G X C----A X T pathway is similar to that found previously in the A X T----G X C pathway (Watanabe, S. M., and Goodman, M.F. (1981) Proc. Natl. Acad. Sci. U.S.A. 78, 2864-2868). We propose a criterion for base selection by DNA polymerase to account for the unexpected similarity in base mispairing rates in the two transition pathways.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11713-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
On the molecular basis of transition mutations. Frequency of forming 2-aminopurine-cytosine base mispairs in the G X C----A X T mutational pathway by T4 DNA polymerase in vitro.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.