Structural highlights
Function
[FLIT_SALTY] Dual-function protein that regulates the transcription of class 2 flagellar operons and that also acts as an export chaperone for the filament-capping protein FliD. As a transcriptional regulator, acts as an anti-FlhDC factor; it directly binds FlhC, thus inhibiting the binding of the FlhC/FlhD complex to class 2 promoters, resulting in decreased expression of class 2 flagellar operons. As a chaperone, effects FliD transition to the membrane by preventing its premature polymerization, and by directing it to the export apparatus.[1] [2] [3] [4]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
For self-assembly of the bacterial flagellum, most of the flagellar component proteins synthesized in the cytoplasm are exported by the flagellar type III export apparatus to the growing, distal end. Flagellar protein export is highly organized and well controlled in every step of the flagellar assembly process. Flagellar-specific chaperones not only facilitate the export of their cognate proteins, as well as prevent their premature aggregation in the cytoplasm, but also play a role in fine-tuning flagellar gene expression to be coupled with the flagellar assembly process. FliT is a flagellar-specific chaperone responsible for the export of the filament-capping protein FliD and for negative control of flagellar gene expression by binding to the FlhDC complex. Here we report the crystal structure of Salmonella FliT at 3.2-A resolution. The structural and biochemical analyses clearly reveal that the C-terminal segment of FliT regulates its interactions with the FlhDC complex, FliI ATPase, and FliJ (subunits of the export apparatus), and that its conformational change is responsible for the switch in its binding partners during flagellar protein export.
Structural insight into the regulatory mechanisms of interactions of the flagellar type III chaperone FliT with its binding partners.,Imada K, Minamino T, Kinoshita M, Furukawa Y, Namba K Proc Natl Acad Sci U S A. 2010 May 11;107(19):8812-7. Epub 2010 Apr 26. PMID:20421493[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Fraser GM, Bennett JC, Hughes C. Substrate-specific binding of hook-associated proteins by FlgN and FliT, putative chaperones for flagellum assembly. Mol Microbiol. 1999 May;32(3):569-80. PMID:10320579
- ↑ Kutsukake K, Ikebe T, Yamamoto S. Two novel regulatory genes, fliT and fliZ, in the flagellar regulon of Salmonella. Genes Genet Syst. 1999 Dec;74(6):287-92. PMID:10791024
- ↑ Bennett JC, Thomas J, Fraser GM, Hughes C. Substrate complexes and domain organization of the Salmonella flagellar export chaperones FlgN and FliT. Mol Microbiol. 2001 Feb;39(3):781-91. PMID:11169117
- ↑ Yamamoto S, Kutsukake K. FliT acts as an anti-FlhD2C2 factor in the transcriptional control of the flagellar regulon in Salmonella enterica serovar typhimurium. J Bacteriol. 2006 Sep;188(18):6703-8. PMID:16952964 doi:http://dx.doi.org/10.1128/JB.00799-06
- ↑ Imada K, Minamino T, Kinoshita M, Furukawa Y, Namba K. Structural insight into the regulatory mechanisms of interactions of the flagellar type III chaperone FliT with its binding partners. Proc Natl Acad Sci U S A. 2010 May 11;107(19):8812-7. Epub 2010 Apr 26. PMID:20421493
