title: An intramolecular upstream helix ensures the stability of a toxin-encoding RNA in Enterococcus faecalis.
abstract: 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.
authors.affiliation: Sanford School of Medicine, University of South Dakota, Vermillion, 57069, USA.
authors.forename: Sonia
authors.initials: S
authors.lastname: Shokeen
authors.forename: Tony J
authors.initials: TJ
authors.lastname: Greenfield
authors.forename: Erik A
authors.initials: EA
authors.lastname: Ehli
authors.forename: Jessica
authors.initials: J
authors.lastname: Rasmussen
authors.forename: Brian E
authors.initials: BE
authors.lastname: Perrault
authors.forename: Keith E
authors.initials: KE
authors.lastname: Weaver
mesh_terms: D020121:5' Untranslated Regions / Q000235:genetics*; D001427:Bacterial Toxins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D004722:Endoribonucleases / Q000378:metabolism; D013293:Enterococcus faecalis / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000235:genetics; D012313:RNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020871:RNA Stability; D016372:RNA, Antisense; D012329:RNA, Bacterial / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D020121:5' Untranslated Regions; D001427:Bacterial Toxins; C042027:RNA I; C034477:RNA primers; D016372:RNA, Antisense; D012329:RNA, Bacterial; C473319:fst toxin, Enterococcus faecalis; D012313:RNA; D004722:Endoribonucleases