3nr7
Crystal structure of S. typhimurium H-NS 1-83Crystal structure of S. typhimurium H-NS 1-83
Structural highlights
FunctionHNS_SALTY H-NS binds tightly to ds-DNA, increases its thermal stability and inhibits transcription. It also binds to ss-DNA and RNA but with a much lower affinity. H-NS has possible histone-like function. May be a global transcriptional regulator through its ability to bind to curved DNA sequences, which are found in regions upstream of a certain subset of promoters. It plays a role in the thermal control of pili production. It is subject to transcriptional auto-repression. It binds preferentially to the upstream region of its own gene recognizing two segments of DNA on both sides of a bend centered around -150 (By similarity). Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe histone-like nucleoid structuring (H-NS) protein plays a fundamental role in DNA condensation and is a key regulator of enterobacterial gene expression in response to changes in osmolarity, pH, and temperature. The protein is capable of high-order self-association via interactions of its oligomerization domain. Using crystallography, we have solved the structure of this complete domain in an oligomerized state. The observed superhelical structure establishes a mechanism for the self-association of H-NS via both an N-terminal antiparallel coiled-coil and a second, hitherto unidentified, helix-turn-helix dimerization interface at the C-terminal end of the oligomerization domain. The helical scaffold suggests the formation of a H-NS:plectonemic DNA nucleoprotein complex that is capable of explaining published biophysical and functional data, and establishes a unifying structural basis for coordinating the DNA packaging and transcription repression functions of H-NS. H-NS forms a superhelical protein scaffold for DNA condensation.,Arold ST, Leonard PG, Parkinson GN, Ladbury JE Proc Natl Acad Sci U S A. 2010 Sep 7;107(36):15728-32. Epub 2010 Aug 23. PMID:20798056[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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