Antitermination

Antitermination is the Procaryotic cell's aid to fix premature termination of RNA synthesis during the transcription of DNA.

If the transcription is terminated prematurely (often after 100 - 1000 base pairs), the antiterminator binds to the transcribed RNA or upstream of the DNA terminator and "re-starts" the transcription.

Important in lambda-phage transcriptional regulation and also a form of positive regulation. In lambda-phage proteins N and Q are antiterminators. N protein prevents termination in early operons of lambda, but not in other phage or bacterial operons.