The bacterial transcription terminator, Rho, functions as an RNA:DNA hybrid (RDH) helicase in vivo.

ABSTRACT: Ribonuclease HI (rnhA) removes the deleterious RNA:DNA hybrids (RDHs) by cleaving its RNA component. The bacterial transcription terminator Rho is an RNA-dependent 5' → 3' helicase capable of unwinding RDH formed on a single-stranded RNA in vitro. We hypothesize that Rho might be directly involved in RDH removal in vivo. Here, we demonstrate that Rho primary RNA-binding site (PBS) mutants defective in RNA binding and helicase activity are synthetically lethal specifically when RNase HI is absent. This lethality was not observed in the absence of RNase HII (rnhB) alone. Rho-PBS mutants in an rnhA- strain exhibited increased plasmid-concatemer and plasmid copy number, altered cell morphology, and were highly susceptible to DNA-damaging agents. These Rho mutants increased the accumulation of

SUBMITTER: Bhosale A 

PROVIDER: S-EPMC12203952 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature