| Structural highlights
Function
RPOS_ECOLI Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released. This sigma factor is the master transcriptional regulator of the stationary phase and the general stress response. Controls, positively or negatively, the expression of several hundred genes, which are mainly involved in metabolism, transport, regulation and stress management.[HAMAP-Rule:MF_00959][1] [2] [3] [4] [5] Protects stationary phase cells from killing induced by endoribonuclease MazF.[6]
Publication Abstract from PubMed
In bacteria, the dissociable sigma subunit of the RNA polymerase (RNAP) is responsible for initiating RNA synthesis from specific DNA sites. As nascent RNA grows, downstream DNA unwinds and is pulled into the RNAP, causing stress accumulation and initiation complex destabilization. Processive transcription elongation requires at least partial separation of the sigma factor from the RNAP core enzyme. Here, we present a series of transcription complexes captured between the early initiation and elongation phases via in-crystal RNA synthesis and cleavage. Crystal structures of these complexes indicate that stress accumulation during transcription initiation is not due to clashing of the growing nascent RNA with the sigma(3.2) loop, but results from scrunching of the template strand DNA that is contained inside the RNAP by the sigma(3) domain. Our results shed light on how scrunching of template-strand DNA drives both abortive initiation and sigma-RNAP core separation to transition transcription from initiation to elongation.
Structural Insights into Transcription Initiation from De Novo RNA Synthesis to Transitioning into Elongation.,Zuo Y, De S, Feng Y, Steitz TA iScience. 2020 Aug 11;23(9):101445. doi: 10.1016/j.isci.2020.101445. PMID:32829286[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Patten CL, Kirchhof MG, Schertzberg MR, Morton RA, Schellhorn HE. Microarray analysis of RpoS-mediated gene expression in Escherichia coli K-12. Mol Genet Genomics. 2004 Dec;272(5):580-91. Epub 2004 Nov 19. PMID:15558318 doi:http://dx.doi.org/10.1007/s00438-004-1089-2
- ↑ Weber H, Polen T, Heuveling J, Wendisch VF, Hengge R. Genome-wide analysis of the general stress response network in Escherichia coli: sigmaS-dependent genes, promoters, and sigma factor selectivity. J Bacteriol. 2005 Mar;187(5):1591-603. PMID:15716429 doi:http://dx.doi.org/10.1128/JB.187.5.1591-1603.2005
- ↑ Rahman M, Hasan MR, Oba T, Shimizu K. Effect of rpoS gene knockout on the metabolism of Escherichia coli during exponential growth phase and early stationary phase based on gene expressions, enzyme activities and intracellular metabolite concentrations. Biotechnol Bioeng. 2006 Jun 20;94(3):585-95. PMID:16511888 doi:http://dx.doi.org/10.1002/bit.20858
- ↑ Maciag A, Peano C, Pietrelli A, Egli T, De Bellis G, Landini P. In vitro transcription profiling of the sigmaS subunit of bacterial RNA polymerase: re-definition of the sigmaS regulon and identification of sigmaS-specific promoter sequence elements. Nucleic Acids Res. 2011 Jul;39(13):5338-55. doi: 10.1093/nar/gkr129. Epub 2011, Mar 11. PMID:21398637 doi:http://dx.doi.org/10.1093/nar/gkr129
- ↑ Tanaka K, Takayanagi Y, Fujita N, Ishihama A, Takahashi H. Heterogeneity of the principal sigma factor in Escherichia coli: the rpoS gene product, sigma 38, is a second principal sigma factor of RNA polymerase in stationary-phase Escherichia coli. Proc Natl Acad Sci U S A. 1993 Apr 15;90(8):3511-5. PMID:8475100
- ↑ Kolodkin-Gal I, Engelberg-Kulka H. The stationary-phase sigma factor sigma(S) is responsible for the resistance of Escherichia coli stationary-phase cells to mazEF-mediated cell death. J Bacteriol. 2009 May;191(9):3177-82. doi: 10.1128/JB.00011-09. Epub 2009 Feb 27. PMID:19251848 doi:http://dx.doi.org/10.1128/JB.00011-09
- ↑ Zuo Y, De S, Feng Y, Steitz TA. Structural Insights into Transcription Initiation from De Novo RNA Synthesis to Transitioning into Elongation. iScience. 2020 Aug 11;23(9):101445. PMID:32829286 doi:10.1016/j.isci.2020.101445
|
