1l9u
From Proteopedia
THERMUS AQUATICUS RNA POLYMERASE HOLOENZYME AT 4 A RESOLUTION
Structural highlights
Function[RPOZ_THEAQ] Promotes RNA polymerase assembly. Latches the N- and C-terminal regions of the beta' subunit thereby facilitating its interaction with the beta and alpha subunits.[1] [Q9EZJ8_THEAQ] Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released (By similarity).[RuleBase:RU000715] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe crystal structure of the initiating form of Thermus aquaticus RNA polymerase, containing core RNA polymerase (alpha2betabeta'omega) and the promoter specificity sigma subunit, has been determined at 4 angstrom resolution. Important structural features of the RNA polymerase and their roles in positioning sigma within the initiation complex are delineated, as well as the role played by sigma in modulating the opening of the RNA polymerase active-site channel. The two carboxyl-terminal domains of sigma are separated by 45 angstroms on the surface of the RNA polymerase, but are linked by an extended loop. The loop winds near the RNA polymerase active site, where it may play a role in initiating nucleotide substrate binding, and out through the RNA exit channel. The advancing RNA transcript must displace the loop, leading to abortive initiation and ultimately to sigma release. Structural basis of transcription initiation: RNA polymerase holoenzyme at 4 A resolution.,Murakami KS, Masuda S, Darst SA Science. 2002 May 17;296(5571):1280-4. PMID:12016306[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|