The carbon storage regulator system in E. coli. A) The RNA-binding protein CsrA (yellow ovals) associates with target transcripts and impedes their translation by interfering with ribosome binding. The non-coding RNA antagonist of CsrA, CsrB (blue star), sequesters CsrA, thereby removing the hindrance that CsrA places on translation of its targets. Not shown here are CsrD and CsrC, protein and RNA negative regulators of CsrA. B) Averaged spectral counts for proteins in the Energy Metabolism TIGR group from samples containing the pBbA5C-CsrB plasmid (induced) or pBbA5C plasmid (uninduced) with 500 uM IPTG harvested at 24 hours after induction. Proteins from the TCA cycle are highlighted in the figure inset. Significant increases were observed in both these groups.