TY - JOUR
T1 - R-Loop in the replication origin of human mitochondrial DNA is resolved by RecG, a Holliday junction-specific helicase
AU - Ohsato, Takashi
AU - Muta, Tsuyoshi
AU - Fukuoh, Atsushi
AU - Shinagawa, Hideo
AU - Hamasaki, Naotaka
AU - Kang, Dongchon
N1 - Funding Information:
This work was supported in part by Grants-in-Aid for Scientific Research from the Ministry of Education, Science, Sports, and Culture of Japan.
PY - 1999/2/5
Y1 - 1999/2/5
N2 - Stable RNA-DNA hybrids (R-loops) prime the initiation of replication in Escherichia coli cells. The R-loops are resolved by Escherichia coli RecG protein, a Holliday junction specific helicase. A stable RNA-DNA hybrid formation in the mitochondrial D-loop region is also implicated in priming the replication of mitochondrial DNA. Consistent with this hypothesis, the 3' ends of the mitochondrial R-loop formed by in vitro transcription are located close to the initiation sites of the mitochondrial DNA replication. This mitochondrial R-loop is resolved by RecG in a dose-dependent manner. Since the resolution by RecG requires ATP, the resolution is dependent on the helicase activity of RecG. A linear RNA-DNA heteroduplex is not resolved by RecG, suggesting that RecG specifically recognizes the higher structure of the mitochondrial R-loop. This is the first example that R-loops of an eukaryotic origin is sensitive to a junction-specific helicase. The resolution of the mitochondrial R-loop by RecG suggests that the replication-priming R-loops have a common structural feature recognized by RecG.
AB - Stable RNA-DNA hybrids (R-loops) prime the initiation of replication in Escherichia coli cells. The R-loops are resolved by Escherichia coli RecG protein, a Holliday junction specific helicase. A stable RNA-DNA hybrid formation in the mitochondrial D-loop region is also implicated in priming the replication of mitochondrial DNA. Consistent with this hypothesis, the 3' ends of the mitochondrial R-loop formed by in vitro transcription are located close to the initiation sites of the mitochondrial DNA replication. This mitochondrial R-loop is resolved by RecG in a dose-dependent manner. Since the resolution by RecG requires ATP, the resolution is dependent on the helicase activity of RecG. A linear RNA-DNA heteroduplex is not resolved by RecG, suggesting that RecG specifically recognizes the higher structure of the mitochondrial R-loop. This is the first example that R-loops of an eukaryotic origin is sensitive to a junction-specific helicase. The resolution of the mitochondrial R-loop by RecG suggests that the replication-priming R-loops have a common structural feature recognized by RecG.
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U2 - 10.1006/bbrc.1998.0133
DO - 10.1006/bbrc.1998.0133
M3 - Article
C2 - 10082645
AN - SCOPUS:0033525023
SN - 0006-291X
VL - 255
SP - 1
EP - 5
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -