Recent studies of T7 RNA polymerase mechanism.

Bacteriophage T7 RNA polymerase (T7 RNAP) is known to be one of the simplest enzymes catalyzing RNA synthesis. In contrast to most RNA polymerases known, this enzyme consists of one subunit and is able to carry out transcription in the absence of additional protein factors. Owing to its molecular properties, the enzyme is widely used for synthesis of specific transcripts, as well as being a suitable model for studying the mechanisms of transcription. In this minireview the recent data on the structure and mechanism of T7 RNAP, including enzyme-promoter interactions, principal stages of transcription, and the results of functional studies are discussed.