Fig. 2.

Mfd-YPet associates with the nucleoid via interactions with RNA polymerase. Schematic describing the initial stages of transcription-coupled repair. a Mfd is recruited to RNA polymerase stalled at bulky lesions (orange star) on the transcribed strand. The arrow indicates the direction of transcription elongation by RNA polymerase. b Substitution of L499 residue with arginine (R) results in the mutant Mfd(L499R) that is unable to rescue stalled transcription complexes. Fluorescence images of Δmfd cells expressing plasmid-based c wild-type Mfd-YPet or d mutant Mfd(L499R)-YPet. White arrows highlight well-defined Mfd-YPet foci. Each image is an average projection of ten continuous 100-ms frames. Scale bar, 2 µm