| Structural highlights
Function
DINJ_ECOLI Antitoxin component of a toxin-antitoxin (TA) module. A labile antitoxin that counteracts the effect of the YafQ toxin. YafQ and DinJ together bind their own promoter, and by analogy to other TA modules probably repress its expression.[1] [2] [3] Cell death governed by the MazE-MazF and DinJ-YafQ TA modules seems to play a role in biofilm formation.[4] [5] [6]
Publication Abstract from PubMed
Bacteria encounter environmental stresses that regulate a gene expression program required for adaptation and survival. Here, we report the 1.8 Angstrom crystal structure of the E. coli toxin-antitoxin complex YafQ-(DinJ)2-YafQ, a key component of the stress response. The antitoxin DinJ dimer adopts a ribbon-helix-helix motif required for transcriptional autorepression while toxin YafQ contains a microbial RNase fold whose proposed active site is concealed by DinJ binding. Contrary to previous reports, our studies indicate that equivalent levels of transcriptional repression occur by direct interaction of either YafQ-(DinJ)2-YafQ or a DinJ dimer at a single inverted repeat of its recognition sequence which overlaps with the -10 promoter region. Surprisingly multiple YafQ-(DinJ)2-YafQ complexes binding to the operator region do not appear to amplify the extent of repression. Our results suggest an alternative model for transcriptional autorepression that may be novel to DinJ-YafQ.
Mechanisms of Toxin Inhibition and Transcriptional Repression by E. coli DinJ-YafQ.,Ruangprasert A, Maehigashi T, Miles SJ, Giridharan N, Liu JX, Dunham CM J Biol Chem. 2014 Jun 4. pii: jbc.M114.573006. PMID:24898247[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Motiejunaite R, Armalyte J, Markuckas A, Suziedeliene E. Escherichia coli dinJ-yafQ genes act as a toxin-antitoxin module. FEMS Microbiol Lett. 2007 Mar;268(1):112-9. PMID:17263853 doi:https://dx.doi.org/10.1111/j.1574-6968.2006.00563.x
- ↑ Prysak MH, Mozdzierz CJ, Cook AM, Zhu L, Zhang Y, Inouye M, Woychik NA. Bacterial toxin YafQ is an endoribonuclease that associates with the ribosome and blocks translation elongation through sequence-specific and frame-dependent mRNA cleavage. Mol Microbiol. 2009 Mar;71(5):1071-87. doi: 10.1111/j.1365-2958.2008.06572.x., Epub 2009 Jan 30. PMID:19210620 doi:https://dx.doi.org/10.1111/j.1365-2958.2008.06572.x
- ↑ Kolodkin-Gal I, Verdiger R, Shlosberg-Fedida A, Engelberg-Kulka H. A differential effect of E. coli toxin-antitoxin systems on cell death in liquid media and biofilm formation. PLoS One. 2009 Aug 26;4(8):e6785. doi: 10.1371/journal.pone.0006785. PMID:19707553 doi:10.1371/journal.pone.0006785
- ↑ Motiejunaite R, Armalyte J, Markuckas A, Suziedeliene E. Escherichia coli dinJ-yafQ genes act as a toxin-antitoxin module. FEMS Microbiol Lett. 2007 Mar;268(1):112-9. PMID:17263853 doi:https://dx.doi.org/10.1111/j.1574-6968.2006.00563.x
- ↑ Prysak MH, Mozdzierz CJ, Cook AM, Zhu L, Zhang Y, Inouye M, Woychik NA. Bacterial toxin YafQ is an endoribonuclease that associates with the ribosome and blocks translation elongation through sequence-specific and frame-dependent mRNA cleavage. Mol Microbiol. 2009 Mar;71(5):1071-87. doi: 10.1111/j.1365-2958.2008.06572.x., Epub 2009 Jan 30. PMID:19210620 doi:https://dx.doi.org/10.1111/j.1365-2958.2008.06572.x
- ↑ Kolodkin-Gal I, Verdiger R, Shlosberg-Fedida A, Engelberg-Kulka H. A differential effect of E. coli toxin-antitoxin systems on cell death in liquid media and biofilm formation. PLoS One. 2009 Aug 26;4(8):e6785. doi: 10.1371/journal.pone.0006785. PMID:19707553 doi:10.1371/journal.pone.0006785
- ↑ Ruangprasert A, Maehigashi T, Miles SJ, Giridharan N, Liu JX, Dunham CM. Mechanisms of Toxin Inhibition and Transcriptional Repression by E. coli DinJ-YafQ. J Biol Chem. 2014 Jun 4. pii: jbc.M114.573006. PMID:24898247 doi:https://dx.doi.org/10.1074/jbc.M114.573006
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