TY - JOUR
T1 - Mechanisms of triplex-caused polymerization arrest
AU - Krasilnikov, Andrey S.
AU - Panyutin, Igor G.
AU - Samadashwily, George M.
AU - Cox, Randal
AU - Lazurkin, Yurii S.
AU - Mirkin, Sergei M.
N1 - Funding Information:
We would like to acknowledge Kevin Kaufman for his help with the computer analysis of the thermal denaturation experiments. This work was supported by grant MCB9405794 from the NSF to S.M.M. and an international supplement to this grant.
PY - 1997/4/1
Y1 - 1997/4/1
N2 - Pyrimidine/purine/purine triplexes are known to inhibit DNA polymerization. Here we have studied the mechanisms of this inhibition by comparing the efficiency of Vent DNA polymerase on triplex- and duplex-containing templates at different temperatures, Mg2+ concentrations and time intervals with the thermal stability of the corresponding structures. Our results show that triplexes can only be by-passed at temperatures where thermal denaturation initiates, while duplexes, in contrast, are overcome at temperatures where they are quite stable. These results show that DNA polymerase cannot untangle triplex regions within DNA templates and seems to entirely depend on their thermal fluctuations. The high stability of triplexes at physiological temperatures and ambient conditions make them a barrier to polymerization.
AB - Pyrimidine/purine/purine triplexes are known to inhibit DNA polymerization. Here we have studied the mechanisms of this inhibition by comparing the efficiency of Vent DNA polymerase on triplex- and duplex-containing templates at different temperatures, Mg2+ concentrations and time intervals with the thermal stability of the corresponding structures. Our results show that triplexes can only be by-passed at temperatures where thermal denaturation initiates, while duplexes, in contrast, are overcome at temperatures where they are quite stable. These results show that DNA polymerase cannot untangle triplex regions within DNA templates and seems to entirely depend on their thermal fluctuations. The high stability of triplexes at physiological temperatures and ambient conditions make them a barrier to polymerization.
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U2 - 10.1093/nar/25.7.1339
DO - 10.1093/nar/25.7.1339
M3 - Article
C2 - 9060427
AN - SCOPUS:0030844557
SN - 0305-1048
VL - 25
SP - 1339
EP - 1346
JO - Nucleic acids research
JF - Nucleic acids research
IS - 7
ER -