5ui8 | pdb_00005ui8
structure of sigmaN-holoenzyme
Structural highlights
Function[RPOZ_ECO45] 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. [RPOA_ECO57] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. [RPOC_ECO57] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. [RPOB_ECO45] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. [A0A0J4U551_KLEPN] Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released.[PIRNR:PIRNR000774] Publication Abstract from PubMedTranscription by RNA polymerase (RNAP) in bacteria requires specific promoter recognition by sigma factors. The major variant sigma factor (sigma(54)) initially forms a transcriptionally silent complex requiring specialized adenosine triphosphate-dependent activators for initiation. Our crystal structure of the 450-kilodalton RNAP-sigma(54) holoenzyme at 3.8 angstroms reveals molecular details of sigma(54) and its interactions with RNAP. The structure explains how sigma(54) targets different regions in RNAP to exert its inhibitory function. Although sigma(54) and the major sigma factor, sigma(70), have similar functional domains and contact similar regions of RNAP, unanticipated differences are observed in their domain arrangement and interactions with RNAP, explaining their distinct properties. Furthermore, we observe evolutionarily conserved regulatory hotspots in RNAPs that can be targeted by a diverse range of mechanisms to fine tune transcription. TRANSCRIPTION. Structures of the RNA polymerase-sigma54 reveal new and conserved regulatory strategies.,Yang Y, Darbari VC, Zhang N, Lu D, Glyde R, Wang YP, Winkelman JT, Gourse RL, Murakami KS, Buck M, Zhang X Science. 2015 Aug 21;349(6250):882-5. doi: 10.1126/science.aab1478. PMID:26293966[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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