RNA‐DNA hybrids form throughout the chromosome during normal growth and under stress conditions. When left unresolved, RNA‐DNA hybrids can slow replication fork progression, cause DNA breaks, and increase mutagenesis. To remove hybrids, all organisms use ribonuclease H (RNase H) to specifically degrade the RNA portion. Here we show that, in addition to chromosomally encoded RNase HII and RNase HIII,
DNA replication complexes (replisomes) routinely encounter proteins and unusual nucleic acid structures that can impede their progress. Barriers can include transcription complexes and R‐loops that form when RNA hybridizes with complementary DNA templates behind RNA polymerases. Cells encode several RNA polymerase and R‐loop clearance mechanisms to limit replisome exposure to these potential obstructions. One such mechanism is hydrolysis of R‐loops by ribonuclease HI (RNase HI). Here, we examine the cellular role of the interaction between
- PAR ID:
- 10158932
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Microbiology
- Volume:
- 114
- Issue:
- 3
- ISSN:
- 0950-382X
- Page Range / eLocation ID:
- p. 495-509
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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