title: Dynamic features of gene expression control by small regulatory RNAs.
abstract: Small regulatory RNAs (sRNAs) in eukaryotes and bacteria play an important role in the regulation of gene expression either by binding to regulatory proteins or directly to target mRNAs. Two of the best-characterized bacterial sRNAs, Spot42 and RyhB, form a complementary pair with the ribosome binding region of their target mRNAs, thereby inhibiting translation or promoting mRNA degradation. To investigate the steady-state and dynamic potential of such sRNAs, we examine the 2 key parameters characterizing sRNA regulation: the capacity to overexpress the sRNA relative to its target mRNA and the speed at which the target mRNA is irreversibly inactivated. We demonstrate different methods to determine these 2 key parameters, for Spot42 and RyhB, which combine biochemical and genetic experiments with computational analysis. We have developed a mathematical model that describes the functional properties of sRNAs with various characteristic parameters. We observed that Spot42 and RyhB function in distinctive parameter regimes, which result in divergent mechanisms.
authors.affiliation: Department of Physics, Kyushu University 33, Fukuoka 812-8581, Japan. mitarai@nbi.dk
authors.forename: Namiko
authors.initials: N
authors.lastname: Mitarai
authors.forename: Julie-Anna M
authors.initials: JA
authors.lastname: Benjamin
authors.forename: Sandeep
authors.initials: S
authors.lastname: Krishna
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Semsey
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Csiszovszki
authors.forename: Eric
authors.initials: E
authors.lastname: Massé
authors.forename: Kim
authors.initials: K
authors.lastname: Sneppen
mesh_terms: D000465:Algorithms; D001426:Bacterial Proteins / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008957:Models, Genetic; D012329:RNA, Bacterial / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D022661:RNA, Untranslated / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D022661:RNA, Untranslated