Global post-transcriptional control of genes involved in amino acid metabolism by the Hfq-dependent GcvB RNA

ABSTRACT: The control of amino acid synthesis and transport in bacteria has been well-investigated at the transcriptional level. The discovery of a small Hfq-dependent regulatory RNA, GcvB, added another layer of gene expression control at the post-transcriptional level. GcvB RNA has been shown to directly regulate multiple ABC transporters for amino acids in E. coli and Salmonella using a highly conserved G/U-rich domain, R1. To identify additional GcvB targets, we have combined a sRNA pulse-expression and microarray analysis of whole transcriptome changes with biocomputational target searches for C/A- rich target sites in Salmonella. Moreover, we have included GcvB mutant RNAs in our microarray approach providing a new target search approach by inactivating conserved domains or target interaction sites. This dual approach revealed further amino acid transporters and, in addition, genes involved in amino acid metabolism as consensus R1-dependent GcvB targets. Moreover, GcvB RNA seems to bind with at least two binding sites to an R1-independent target, the glycine transporter cycA. Using GFP reporter gene fusions we have now validated 21 GcvB targets which is best to our knowledge with ~1% of all Salmonella protein coding genes, the largest bacterial sRNA-controlled regulon. Intriguingly, GcvB rewires many primary control circuits and, thus, constitutes an important metabolic knot.

ORGANISM(S): Salmonella enterica subsp. enterica serovar Typhimurium str. SL1344

PROVIDER: GSE26573 | GEO | 2011/07/01

SECONDARY ACCESSION(S): PRJNA136245

REPOSITORIES: GEO