RNAP_II_Rpb7_N: Rpb7, N-terminal ribonucleoprotein (RNP) domain. Rpb7 is a subunit of eukaryotic RNA polymerase (RNAP) II that is homologous to Rpc25 of RNAP III, RpoE of archaeal RNAP, and Rpa43 of eukaryotic RNAP I. Rpb7 heterodimerizes with Rpb4 and this heterodimer binds the 10-subunit core of RNAP II, forming part of the floor of the DNA-binding cleft. Rpb7 has two domains, an N-terminal RNP domain and a C-terminal oligonucleotide-binding (OB) domain, both of which bind single-stranded RNA. Rpb7 is thought to interact with the nascent RNA strand as it exits the RNAP II complex during transcription elongation. The Rpb7/Rpb4 heterodimer is also thought to serve as an upstream interface between the C-terminal domain of Rpb1 and the transcription factor IIB (TFIIB), recruiting pol II to the pol II promoter.
Jiyao W et al.(2023). "The conserved domain database in 2023.",