Globally modulates RNA abundance by binding to RNase E (Rne) and regulating its endonucleolytic activity. Can modulate Rne action in a substrate-dependent manner by altering the composition of the degradosome. Modulates RNA-binding and helicase activities of the degradosome. Homotrimer. Binds to both RNA-binding sites in the C-terminal region of Rne and to RhlB. Belongs to the RraA family.