The binding of Class II sRNA MgrR to two different sites on matchmaker protein Hfq enables efficient competition for Hfq and annealing to regulated mRNAs

Global modeling of MgrR annealing to eptB133 with mutations in AU1 and AU2 sequence motifs (mutants eptB133_AU1_v2, eptB133_AU2_v2, and eptB133_AU1_AU2). The native gel analysis of the kinetics of ³²P-labeled MgrR annealing to (i) eptB133_AU1_v2 in the absence of Hfq (A) or the presence of Hfq (B), (ii) eptB133_AU2_v2 in the absence of Hfq (C) or the presence of Hfq (D), and (iii) eptB133_AU1_AU2 in the absence of Hfq (E) or the presence of Hfq (F). The data for the annealing of MgrR to each of the mRNA mutants in the absence and the presence of wt Hfq were analyzed globally, and the lines in the plots are the results of global fitting. The RNAs and their complexes are marked in the same way as in Figure 5.