Fig. 6.

The λpR′ σ⁷⁰-dependent pause cycle. Pause induction occurs when, at +13, σ⁷⁰ binds the −10-like sequence and anchors RNAP to the DNA template. The −10-like sequence-bound TEC continues RNA synthesis to +16, at which point RNAP either proceeds rapidly to a posttranslocated conformation or enters an elemental paused state induced by the EPS. Upon entering a posttranslocated conformation at +16, RNA synthesis continues to +17 and RNAP either disengages the −10-like sequence and escapes the pause or fails to disengage the −10-like sequence and enters a backtracked conformation. The backtracked complex is then rescued by Gre-mediated transcript cleavage and so that subsequent escape attempts can be made until σ⁷⁰ releases the −10-like sequence.