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<table><tr><td colspan='2'>[[6jbq]] is a 9 chain structure with sequence from [http://en.wikipedia.org/wiki/Ecoli Ecoli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6JBQ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6JBQ FirstGlance]. <br>
<table><tr><td colspan='2'>[[6jbq]] is a 9 chain structure with sequence from [http://en.wikipedia.org/wiki/Ecoli Ecoli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6JBQ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6JBQ FirstGlance]. <br>
6jbq is a 9 chain structure with sequence from Ecoli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[RPOC_ECOLI] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_01322] [RPOB_ECOLI] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_01321] [RPOA_ECOLI] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. This subunit plays an important role in subunit assembly since its dimerization is the first step in the sequential assembly of subunits to form the holoenzyme.[HAMAP-Rule:MF_00059] [RPOZ_ECOLI] 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.[HAMAP-Rule:MF_00366] [RPOE_ECOLI] Sigma factors are initiation factors that promote the attachment of RNA polymerase (RNAP) to specific initiation sites and are then released. Extracytoplasmic function (ECF) sigma-E controls the envelope stress response, responding to periplasmic protein stress, increased levels of periplasmic lipopolysaccharide (LPS) as well as heat shock and oxidative stress; it controls protein processing in the extracytoplasmic compartment. The 90 member regulon consists of the genes necessary for the synthesis and maintenance of both proteins and LPS of the outer membrane.[1][2][3][4][5][6]
Publication Abstract from PubMed
Bacterial RNA polymerase (RNAP) forms distinct holoenzymes with extra-cytoplasmic function (ECF) sigma factors to initiate specific gene expression programs. In this study, we report a cryo-EM structure at 4.0 A of Escherichia coli transcription initiation complex comprising sigmaE-the most-studied bacterial ECF sigma factor (Ec sigmaE-RPo), and a crystal structure at 3.1 A of Mycobacterium tuberculosis transcription initiation complex with a chimeric sigmaH/E (Mtb sigmaH/E-RPo). The structure of Ec sigmaE-RPo reveals key interactions essential for assembly of E. coli sigmaE-RNAP holoenzyme and for promoter recognition and unwinding by E. coli sigmaE. Moreover, both structures show that the non-conserved linkers (sigma2/sigma4 linker) of the two ECF sigma factors are inserted into the active-center cleft and exit through the RNA-exit channel. We performed secondary-structure prediction of 27,670 ECF sigma factors and find that their non-conserved linkers probably reach into and exit from RNAP active-center cleft in a similar manner. Further biochemical results suggest that such sigma2/sigma4 linker plays an important role in RPo formation, abortive production and promoter escape during ECF sigma factors-mediated transcription initiation.
Structures and mechanism of transcription initiation by bacterial ECF factors.,Fang C, Li L, Shen L, Shi J, Wang S, Feng Y, Zhang Y Nucleic Acids Res. 2019 May 27. pii: 5498757. doi: 10.1093/nar/gkz470. PMID:31131408[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Raina S, Missiakas D, Georgopoulos C. The rpoE gene encoding the sigma E (sigma 24) heat shock sigma factor of Escherichia coli. EMBO J. 1995 Mar 1;14(5):1043-55. PMID:7889935
↑ Rouviere PE, De Las Penas A, Mecsas J, Lu CZ, Rudd KE, Gross CA. rpoE, the gene encoding the second heat-shock sigma factor, sigma E, in Escherichia coli. EMBO J. 1995 Mar 1;14(5):1032-42. PMID:7889934
↑ Erickson JW, Gross CA. Identification of the sigma E subunit of Escherichia coli RNA polymerase: a second alternate sigma factor involved in high-temperature gene expression. Genes Dev. 1989 Sep;3(9):1462-71. PMID:2691330
↑ Missiakas D, Mayer MP, Lemaire M, Georgopoulos C, Raina S. Modulation of the Escherichia coli sigmaE (RpoE) heat-shock transcription-factor activity by the RseA, RseB and RseC proteins. Mol Microbiol. 1997 Apr;24(2):355-71. PMID:9159522
↑ De Las Penas A, Connolly L, Gross CA. The sigmaE-mediated response to extracytoplasmic stress in Escherichia coli is transduced by RseA and RseB, two negative regulators of sigmaE. Mol Microbiol. 1997 Apr;24(2):373-85. PMID:9159523
↑ Rhodius VA, Suh WC, Nonaka G, West J, Gross CA. Conserved and variable functions of the sigmaE stress response in related genomes. PLoS Biol. 2006 Jan;4(1):e2. PMID:16336047 doi:http://dx.doi.org/10.1371/journal.pbio.0040002
↑ Fang C, Li L, Shen L, Shi J, Wang S, Feng Y, Zhang Y. Structures and mechanism of transcription initiation by bacterial ECF factors. Nucleic Acids Res. 2019 May 27. pii: 5498757. doi: 10.1093/nar/gkz470. PMID:31131408 doi:http://dx.doi.org/10.1093/nar/gkz470
