RNA polymerases catalyse the DNA dependent polymerisation of RNA. Prokaryotes contain a single RNA polymerase compared to three in eukaryotes (not including mitochondrial. and chloroplast polymerases). This domain represents the hybrid binding domain and the wall domain [1]. The hybrid binding domain binds the nascent RNA strand / template DNA strand in the Pol II transcription elongation complex. This domain contains the important structural motifs, switch 3 and the flap loop and binds an active site metal [1]. This domain is also involved in binding to Rpb1 and Rpb3 [1]. Many of the bacterial members contain large insertions within this domain, as region known as dispensable region 2 (DRII).
RNA polymerases (EC) catalyse the DNA dependent polymerisation of RNA. Prokaryotes contain a single RNA polymerase compared to three in eukaryotes (not including mitochondrial and chloroplast polymerases). This domain represents the hybrid-binding domain and the wall domain [PUBMED:11313498]. The hybrid-binding domain binds the nascent RNA strand/template DNA strand in the Pol II transcription elongation complex. This domain contains the important structural motifs, switch 3 and the flap loop and binds an active site metal ion [PUBMED:11313498]. This domain is also involved in binding to Rpb1 and Rpb3 [PUBMED:11313498]. Many of the bacterial members contain large insertions within this domain, which are known as dispensable region 2 (DRII).
Cramer P, Bushnell DA, Kornberg RD; , Science 2001;292:1863-1876.: Structural basis of transcription: RNA polymerase II at 2.8 angstrom resolution. PUBMED:11313498 EPMC:11313498.