RaRp

In autumn 2006, the US chemist Roger D. Kornberg (Stanford University) was awarded the Nobel Prize in Chemistry for the elucidation of the mechanism of transcription (transcription of DNA into RNA) by means of RNA polymerase.

RaRp is the acronym for "RNA-dependent RNA polymerase". In prokaryotes, there is only one form of RNA polymerase. In eukaryotes, three forms of RNA polymerase are distinguished:

• RNA polymerase I, which catalyzes the formation of rRNA as pre-rRNA (45S is processed to 18S; 5.8S; 28S) and some snRNAs (small nuclear RNA) in the nucleolus,
• RNA polymerase II, which catalyzes the formation of most mRNA, and
• RNA polymerase III, which catalyzes the formation of tRNA, 7SL RNA, and 5S rRNA.

These RNA polymerases are DNA dependent. RNA polymerase II and III are inhibited by alpha-amanitin.