Structural highlights
Function
RSSB_ECOLI Regulates the turnover of the sigma S factor (RpoS) by promoting its proteolysis in exponentially growing cells. Acts by binding and delivering RpoS to the ClpXP protease. RssB is not co-degraded with RpoS, but is released from the complex and can initiate a new cycle of RpoS recognition and degradation. In stationary phase, could also act as an anti-sigma factor and reduce the ability of RpoS to activate gene expression. Is also involved in the regulation of the mRNA polyadenylation pathway during stationary phase, probably by maintaining the association of PcnB with the degradosome.[HAMAP-Rule:MF_00958][1] [2] [3] [4] [5] [6]
Publication Abstract from PubMed
In the model organism Escherichia coli and related species, the general stress response relies on tight regulation of the intracellular levels of the promoter specificity subunit RpoS. RpoS turnover is exclusively dependent on RssB, a two-domain response regulator that functions as an adaptor that delivers RpoS to ClpXP for proteolysis. Here, we report crystal structures of the receiver domain of RssB both in its unphosphorylated form and bound to the phosphomimic BeF3 (-) . Surprisingly, we find only modest differences between these two structures, suggesting that truncating RssB may partially activate the receiver domain to a "meta-active" state. Our structural and sequence analysis points to RssB proteins not conforming to either the Y-T coupling scheme for signaling seen in prototypical response regulators, such as CheY, or to the signaling model of the less understood FATGUY proteins.
Phospho-dependent signaling during the general stress response by the atypical response regulator and ClpXP adaptor RssB.,Schwartz J, Son J, Brugger C, Deaconescu AM Protein Sci. 2021 Apr;30(4):899-907. doi: 10.1002/pro.4047. Epub 2021 Mar 1. PMID:33599047[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Becker G, Klauck E, Hengge-Aronis R. The response regulator RssB, a recognition factor for sigmaS proteolysis in Escherichia coli, can act like an anti-sigmaS factor. Mol Microbiol. 2000 Feb;35(3):657-66. PMID:10672187 doi:10.1046/j.1365-2958.2000.01736.x
- ↑ Klauck E, Lingnau M, Hengge-Aronis R. Role of the response regulator RssB in sigma recognition and initiation of sigma proteolysis in Escherichia coli. Mol Microbiol. 2001 Jun;40(6):1381-90. PMID:11442836 doi:10.1046/j.1365-2958.2001.02482.x
- ↑ Carabetta VJ, Mohanty BK, Kushner SR, Silhavy TJ. The response regulator SprE (RssB) modulates polyadenylation and mRNA stability in Escherichia coli. J Bacteriol. 2009 Nov;191(22):6812-21. PMID:19767441 doi:10.1128/JB.00870-09
- ↑ Carabetta VJ, Silhavy TJ, Cristea IM. The response regulator SprE (RssB) is required for maintaining poly(A) polymerase I-degradosome association during stationary phase. J Bacteriol. 2010 Jul;192(14):3713-21. PMID:20472786 doi:10.1128/JB.00300-10
- ↑ Muffler A, Fischer D, Altuvia S, Storz G, Hengge-Aronis R. The response regulator RssB controls stability of the sigma(S) subunit of RNA polymerase in Escherichia coli. EMBO J. 1996 Mar 15;15(6):1333-9 PMID:8635466
- ↑ Pratt LA, Silhavy TJ. The response regulator SprE controls the stability of RpoS. Proc Natl Acad Sci U S A. 1996 Mar 19;93(6):2488-92. PMID:8637901 doi:10.1073/pnas.93.6.2488
- ↑ Schwartz J, Son J, Brugger C, Deaconescu AM. Phospho-dependent signaling during the general stress response by the atypical response regulator and ClpXP adaptor RssB. Protein Sci. 2021 Apr;30(4):899-907. PMID:33599047 doi:10.1002/pro.4047
