RprA RNA

The RprA RNA gene encodes a 106 nucleotide regulatory non-coding RNA. Translational regulation of the stationary phase sigma factor RpoS is mediated by the formation of a double-stranded RNA stem-loop structure in the upstream region of the rpoS messenger RNA, occluding the translation initiation site.^[1][2]

RprA RNA
Predicted secondary structure and sequence conservation of RprA
Identifiers
Symbol	RprA
Rfam	RF00034
Other data
RNA type	Gene; sRNA
Domain(s)	Bacteria
SO	SO:0000387
PDB structures	PDBe

Clones carrying rprA (RpoS regulator RNA A) increased the translation of RpoS. As with DsrA, RprA is predicted to form three stem-loops. Thus, at least two small RNAs, DsrA and RprA, participate in the positive regulation of RpoS translation. RprA also appears to bind to the RpoS leader.^[3] RprA is non-essential.^[4] Wasserman et al. demonstrated that this RNA is bound by the Hfq protein.^[5] Binding to Hfq alters the conformation of RprA.^[6] In the presence of Hfq the stability of RprA is influenced by the osmolarity of the cell, this is dependent on the endoribonuclease RNase E.^[7]

It has been shown the RprA regulates the protein coding genes, called csgD, this protein encodes a stationary phase-induced biofilm regulator and ydaM, which encodes a diguanylate cyclase involved in activating csgD transcription. These two target genes are repressed by RprA which results in regulation of biofilm formation.^[8]