TY - JOUR
T1 - A Mechanism of Nucleotide Misincorporation during Transcription due to Template-Strand Misalignment
AU - Pomerantz, Richard T.
AU - Temiakov, Dmitry
AU - Anikin, Michael
AU - Vassylyev, Dmitry G.
AU - McAllister, William T.
N1 - Funding Information:
This work was supported by National Institutes of Health grant GM38147 to W.T.M. and GM74252 to D.G.V. We are grateful to Mr. Ray Castagna for expert technical assistance.
PY - 2006/10/20
Y1 - 2006/10/20
N2 - Transcription errors by T7 RNA polymerase (RNAP) may occur as the result of a mechanism in which the template base two positions downstream of the 3′ end of the RNA (the TSn+1 base) is utilized during two consecutive nucleotide-addition cycles. In the first cycle, misalignment of the template strand leads to incorporation of a nucleotide that is complementary to the TSn+1 base. In the second cycle, the template is realigned and the mismatched primer is efficiently extended, resulting in a substitution error. Proper organization of the transcription bubble is required for maintaining the correct register of the DNA template, as the presence of a complementary nontemplate strand opposite the TSn+1 base suppresses template misalignment. Our findings for T7 RNAP are in contrast to related DNA polymerases of the Pol I type, which fail to extend mismatches efficiently and generate predominately deletion errors as a result of template-strand misalignment.
AB - Transcription errors by T7 RNA polymerase (RNAP) may occur as the result of a mechanism in which the template base two positions downstream of the 3′ end of the RNA (the TSn+1 base) is utilized during two consecutive nucleotide-addition cycles. In the first cycle, misalignment of the template strand leads to incorporation of a nucleotide that is complementary to the TSn+1 base. In the second cycle, the template is realigned and the mismatched primer is efficiently extended, resulting in a substitution error. Proper organization of the transcription bubble is required for maintaining the correct register of the DNA template, as the presence of a complementary nontemplate strand opposite the TSn+1 base suppresses template misalignment. Our findings for T7 RNAP are in contrast to related DNA polymerases of the Pol I type, which fail to extend mismatches efficiently and generate predominately deletion errors as a result of template-strand misalignment.
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U2 - 10.1016/j.molcel.2006.08.014
DO - 10.1016/j.molcel.2006.08.014
M3 - Article
C2 - 17052458
AN - SCOPUS:33749681925
SN - 1097-2765
VL - 24
SP - 245
EP - 255
JO - Molecular Cell
JF - Molecular Cell
IS - 2
ER -