InterPro domain: IPR006592

The task of transcribing nuclear genes is shared between three RNA polymerases in eukaryotes: RNA polymerase (pol) I synthesizes the large rRNA, pol II synthesizes mRNA and pol III synthesizes tRNA and 5S rRNA [ 1 ]. Pol I transcription is localised to discrete sites called nucleoli; these can be likened to ribosomefactories, in which rRNA is synthesised by pol I in the fibrillar centres and then processed and assembled into ribosomes inthe surrounding granular regions [ 2 ]. Prokaryotes, in contrast, posses a single RNA polymerase, with transcription being controlled by the particular signam factor interacting with the catalytic core.

This entry describes an N-terminal conserved region which can be found in the largest subunits of prokaryoptic and eukaryotic RNA polymerases.

1. Survey and summary: transcription by RNA polymerases I and III. Nucleic Acids Res. 28, 1283-98
2. The nucleolus. Annu. Rev. Cell Dev. Biol. 11, 93-121