Fig. 1.

Actively transcribing RCs move to and coalesce at speckles to form RNA export/processing structures. (A and B) Progeny DNA (black) in a stationary RC undergoes actin (blue) and RNA pol II (white) -mediated transcription (yellow) of true late genes such as gC. (C and D) Myosin (pink) is recruited to the transcribing RC and triggers movement of the RC away from the associated speckle. (E) The mobile RC moves to another RC-associated speckle and moves on the surface of the speckle to merge with the other RC. (F) Coalescence of RCs on the speckle surface leads to a reorganization of RCs, allowing for efficient incorporation of RNA processing factors and the processing of true late transcripts in the speckle, which ultimately create an RNA export/processing hub.