Related Experiment Video
Updated: Jun 4, 2026

MS2-Affinity Purification Coupled with RNA Sequencing in Gram-Positive Bacteria
Published on: February 23, 2021
The base-pairing RNA spot 42 participates in a multioutput feedforward loop to help enact catabolite repression in
1Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892-5430, USA. beiselcl@mail.nih.gov
Abstract:
Bacteria selectively consume some carbon sources over others through a regulatory mechanism termed catabolite repression. Here, we show that the base-pairing RNA Spot 42 plays a broad role in catabolite repression in Escherichia coli by directly repressing genes involved in central and secondary metabolism, redox balancing, and the consumption of diverse nonpreferred carbon sources. Many of the genes repressed by Spot 42 are transcriptionally activated by the global regulator CRP. Since CRP represses Spot 42, these regulators participate in a specific regulatory circuit called a multioutput feedforward loop. We found that this loop can reduce leaky expression of target genes in the presence of glucose and can maintain repression of target genes under changing nutrient conditions. Our results suggest that base-pairing RNAs in feedforward loops can help shape the steady-state levels and dynamics of gene expression.
Related Concept Videos
Stringent Response in E. coli
Coordination of Gene Expression Processes in Bacteria
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Repressible Operon: trp Operon
Riboswitches
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...

