An intramolecular upstream helix ensures the stability of a toxin-encoding RNA in Enterococcus faecalis.

Autor: Shokeen S; Sanford School of Medicine, University of South Dakota, Vermillion, 57069, USA., Greenfield TJ, Ehli EA, Rasmussen J, Perrault BE, Weaver KE
Jazyk: angličtina
Zdroj: Journal of bacteriology [J Bacteriol] 2009 Mar; Vol. 191 (5), pp. 1528-36. Date of Electronic Publication: 2008 Dec 19.
DOI: 10.1128/JB.01316-08
Abstrakt: The par stability determinant is required for the stable inheritance of the plasmid pAD1 in its native host, Enterococcus faecalis. It is the only antisense RNA-regulated addiction module identified to date in gram-positive bacteria. It encodes two small, convergently transcribed RNAs, RNA I and RNA II. RNA I encodes the Fst toxin and RNA II acts as the antitoxin by interacting with RNA I posttranscriptionally. As the toxin-encoding component of the system, it is important that RNA I is more stable than RNA II. This study reveals that a helix sequestering the 5' end of RNA I plays a crucial role in maintaining the stability of the RNA I. An adjacent structure previously determined to regulate Fst translation was not required to enhance stability. Results indicated that endoribonuclease J2 contributes significantly to the degradation of a mutant disrupting the upstream helix (UH) of RNA I in Bacillus subtilis. Finally, it was shown that interaction with RNA II stabilized the UH mutant of RNA I.
Databáze: MEDLINE