Fig 2. CsrA specifically interacts with the leader region of the hilE transcript.

(A) CsrA binding to the hilE RNA was analyzed using EMSAs by incubating labeled hilE RNA (0.2 nM) with increasing concentrations of purified CsrA (0, 2.3, 4.7, 9.4, 19, 38, 75, 150 and 300 nM). Positions of bound and free RNA are marked. These experiments were performed three times and a representative gel is shown. (B) RNA competition experiment where labeled hilE RNA (0.2 nM) was combined with 1, 10 and 100 nM of unlabeled specific (hilE) or non-specific (phoB) competitor RNA and incubated with 0 and 75 nM of purified CsrA. Positions of bound and free RNA are marked. A representative gel from two independent assays is shown.