title: The small RNA SraG participates in PNPase homeostasis.
abstract: The rpsO-pnp operon encodes ribosomal protein S15 and polynucleotide phosphorylase, a major 3'-5' exoribonuclease involved in mRNA decay in Escherichia coli The gene for the SraG small RNA is located between the coding regions of the rpsO and pnp genes, and it is transcribed in the opposite direction relative to the two genes. No function has been assigned to SraG. Multiple levels of post-transcriptional regulation have been demonstrated for the rpsO-pnp operon. Here we show that SraG is a new factor affecting pnp expression. SraG overexpression results in a reduction of pnp expression and a destabilization of pnp mRNA; in contrast, inhibition of SraG transcription results in a higher level of the pnp transcript. Furthermore, in vitro experiments indicate that SraG inhibits translation initiation of pnp Together, these observations demonstrate that SraG participates in the post-transcriptional control of pnp by a direct antisense interaction between SraG and PNPase RNAs. Our data reveal a new level of regulation in the expression of this major exoribonuclease.
authors: CNRS UMR8261 (previously FRE3630) associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France.
authors: Fanette
authors: F
authors: Fontaine
authors: CNRS UMR8261 (previously FRE3630) associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France.
authors: Elise
authors: E
authors: Gasiorowski
authors: CNRS UMR8261 (previously FRE3630) associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France.
authors: Celine
authors: C
authors: Gracia
authors: CNRS UMR8261 (previously FRE3630) associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France.
authors: Mathieu
authors: M
authors: Ballouche
authors: CNRS UMR8261 (previously FRE3630) associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France.
authors: Joel
authors: J
authors: Caillet
authors: Institut de Génétique et Microbiologie, CNRS/UMR 8621, Université Paris Sud, 91405 Orsay, France.
authors: Antonin
authors: A
authors: Marchais
authors: CNRS UMR8261 (previously FRE3630) associated with University Paris Diderot, Sorbonne Paris Cité, Institut de Biologie Physico-Chimique, 75005 Paris, France.
authors: Eliane
authors: E
authors: Hajnsdorf
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006706:Homeostasis; D009876:Operon; D011117:Polyribonucleotide Nucleotidyltransferase / Q000235:genetics* / Q000378:metabolism; D012329:RNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011117:Polyribonucleotide Nucleotidyltransferase
keywords: PNPase; SraG; antisense RNA; post-transcriptional regulation