Structural highlights
Function
[RPC9_YEAST] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Specific peripheric component of RNA polymerase III which synthesizes small RNAs, such as 5S rRNA and tRNAs. The RPC25/RPC8-RPC17/RPC9 subcomplex may bind Pol III transcripts emerging from the adjacent exit pore during elongation. [RPC8_YEAST] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Specific peripheric component of RNA polymerase III which synthesizes small RNAs, such as 5S rRNA and tRNA. The RPC25/RPC8-RPC17/RPC9 subcomplex may bind Pol III transcripts emerging from the adjacent exit pore during elongation.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
We obtained an 11 subunit model of RNA polymerase (Pol) III by combining a homology model of the nine subunit core enzyme with a new X-ray structure of the subcomplex C17/25. Compared to Pol II, Pol III shows a conserved active center for RNA synthesis but a structurally different upstream face for specific initiation complex assembly during promoter selection. The Pol III upstream face includes a HRDC domain in subunit C17 that is translated by 35 A and rotated by 150 degrees compared to its Pol II counterpart. The HRDC domain is essential in vivo, folds independently in vitro, and, unlike other HRDC domains, shows no indication of nucleic acid binding. Thus, the HRDC domain is a functional module that could account for the role of C17 in Pol III promoter-specific initiation. During elongation, C17/25 may bind Pol III transcripts emerging from the adjacent exit pore, because the subcomplex binds to tRNA in vitro.
Structural biology of RNA polymerase III: subcomplex C17/25 X-ray structure and 11 subunit enzyme model.,Jasiak AJ, Armache KJ, Martens B, Jansen RP, Cramer P Mol Cell. 2006 Jul 7;23(1):71-81. PMID:16818233[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Jasiak AJ, Armache KJ, Martens B, Jansen RP, Cramer P. Structural biology of RNA polymerase III: subcomplex C17/25 X-ray structure and 11 subunit enzyme model. Mol Cell. 2006 Jul 7;23(1):71-81. PMID:16818233 doi:10.1016/j.molcel.2006.05.013
