| Structural highlights
Function
[HSLU_ECOLI] ATPase subunit of a proteasome-like degradation complex; this subunit has chaperone activity. The binding of ATP and its subsequent hydrolysis by HslU are essential for unfolding of protein substrates subsequently hydrolyzed by HslV. HslU recognizes the N-terminal part of its protein substrates and unfolds these before they are guided to HslV for hydrolysis.[1] [2] [3] [4] [5] [6] [7]
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
The degradation of cytoplasmic proteins is an ATP-dependent process. Substrates are targeted to a single soluble protease, the 26S proteasome, in eukaryotes and to a number of unrelated proteases in prokaryotes. A surprising link emerged with the discovery of the ATP-dependent protease HslVU (heat shock locus VU) in Escherichia coli. Its protease component HslV shares approximately 20% sequence similarity and a conserved fold with 20S proteasome beta-subunits. HslU is a member of the Hsp100 (Clp) family of ATPases. Here we report the crystal structures of free HslU and an 820,000 relative molecular mass complex of HslU and HslV-the first structure of a complete set of components of an ATP-dependent protease. HslV and HslU display sixfold symmetry, ruling out mechanisms of protease activation that require a symmetry mismatch between the two components. Instead, there is conformational flexibility and domain motion in HslU and a localized order-disorder transition in HslV. Individual subunits of HslU contain two globular domains in relative orientations that correlate with nucleotide bound and unbound states. They are surprisingly similar to their counterparts in N-ethylmaleimide-sensitive fusion protein, the prototype of an AAA-ATPase. A third, mostly alpha-helical domain in HslU mediates the contact with HslV and may be the structural equivalent of the amino-terminal domains in proteasomal AAA-ATPases.
The structures of HsIU and the ATP-dependent protease HsIU-HsIV.,Bochtler M, Hartmann C, Song HK, Bourenkov GP, Bartunik HD, Huber R Nature. 2000 Feb 17;403(6771):800-5. PMID:10693812[8]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Yoo SJ, Seol JH, Shin DH, Rohrwild M, Kang MS, Tanaka K, Goldberg AL, Chung CH. Purification and characterization of the heat shock proteins HslV and HslU that form a new ATP-dependent protease in Escherichia coli. J Biol Chem. 1996 Jun 14;271(24):14035-40. PMID:8662828
- ↑ Rohrwild M, Coux O, Huang HC, Moerschell RP, Yoo SJ, Seol JH, Chung CH, Goldberg AL. HslV-HslU: A novel ATP-dependent protease complex in Escherichia coli related to the eukaryotic proteasome. Proc Natl Acad Sci U S A. 1996 Jun 11;93(12):5808-13. PMID:8650174
- ↑ Seol JH, Yoo SJ, Shin DH, Shim YK, Kang MS, Goldberg AL, Chung CH. The heat-shock protein HslVU from Escherichia coli is a protein-activated ATPase as well as an ATP-dependent proteinase. Eur J Biochem. 1997 Aug 1;247(3):1143-50. PMID:9288941
- ↑ Kanemori M, Nishihara K, Yanagi H, Yura T. Synergistic roles of HslVU and other ATP-dependent proteases in controlling in vivo turnover of sigma32 and abnormal proteins in Escherichia coli. J Bacteriol. 1997 Dec;179(23):7219-25. PMID:9393683
- ↑ Seong IS, Oh JY, Yoo SJ, Seol JH, Chung CH. ATP-dependent degradation of SulA, a cell division inhibitor, by the HslVU protease in Escherichia coli. FEBS Lett. 1999 Jul 30;456(1):211-4. PMID:10452560
- ↑ Kanemori M, Yanagi H, Yura T. Marked instability of the sigma(32) heat shock transcription factor at high temperature. Implications for heat shock regulation. J Biol Chem. 1999 Jul 30;274(31):22002-7. PMID:10419524
- ↑ Burton RE, Baker TA, Sauer RT. Nucleotide-dependent substrate recognition by the AAA+ HslUV protease. Nat Struct Mol Biol. 2005 Mar;12(3):245-51. Epub 2005 Feb 6. PMID:15696175 doi:10.1038/nsmb898
- ↑ Bochtler M, Hartmann C, Song HK, Bourenkov GP, Bartunik HD, Huber R. The structures of HsIU and the ATP-dependent protease HsIU-HsIV. Nature. 2000 Feb 17;403(6771):800-5. PMID:10693812 doi:10.1038/35001629
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