Raghunathan, Nalini and Kapshikar, R.M. and Leela, J.K. and Mallikarjun, J. and Bouloc, P. and Gowrishankar, J. (2018) Genome-wide relationship between R-loop formation and antisense transcription in Escherichia coli. Nucleic Acids Research, 46 (7). pp. 3400-3411. ISSN 0305-1048

Preview

Text NAR 46 p3400.pdf Download (4Mb) | Preview

Abstract

Transcription termination by Rho is essential for viability in various bacteria, including some major pathogens. Since Rho acts by targeting nascent RNAs that are not simultaneously translated, it also regulates antisense transcription. Here we show that RNase H-deficient mutants of Escherichia coli exhibit heightened sensitivity to the Rho inhibitor bicyclomycin, and that Rho deficiency provokes increased formation of RNA-DNA hybrids (R-loops) which is ameliorated by expression of the phage T4-derived R-loop helicase UvsW. We also provide evidence that in Rho-deficient cells, R-loop formation blocks subsequent rounds of antisense transcription at more than 500 chromosomal loci. Hence these antisense transcripts, which can extend beyond 10 kb in their length, are only detected when Rho function is absent or compromised and the UvsW helicase is concurrently expressed. Thus the potential for antisense transcription in bacteria is much greater than hitherto recognized; and the cells are able to retain viability even when nearly one-quarter of their total non-rRNA abundance is accounted for by antisense transcripts, provided that R-loop formation from them is curtailed.

Item Type:	Article
Uncontrolled Keywords:	Gene Regulation, Chromatin and Epigenetics
Depositing User:	Users 2 not found.
Date Deposited:	28 Feb 2018 18:39
Last Modified:	25 Apr 2018 10:19
URI:	http://cdfd.sciencecentral.in/id/eprint/828

Actions (login required)

View Item