Crystal structure and RNA binding of the Tex protein from Pseudomonas aeruginosa

JOURNAL OF MOLECULAR BIOLOGY

卷:377

Article

Johnson, Sean J.²  Close, Devin¹  Robinson, Howard³  Vallet-Gely, Isabelle⁴  Dove, Simon L.⁴  Hill, Christopher P.¹ 

[1] Univ Utah, Dept Biochem, Salt Lake City, UT 84112 USA

[2] Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 USA

[3] Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA

[4] Harvard Univ, Sch Med, Childrens Hosp, Div Infect Dis, Boston, MA 02115 USA

关键词: transcription;    S1 domain;    Tex;    x-ray crystallography;    Spt6;   

DOI  :  10.1016/j.jmb.2008.01.096

来源: Elsevier

【 摘 要 】

Tex is a highly conserved bacterial protein that likely functions in a variety of transcriptional processes. Here, we describe two crystal structures of the 86-kDa Tex protein from Pseudomonas aeruginosa at 2.3 and 2.5 angstrom resolution, respectively. These structures reveal a relatively flat and elongated protein, with several potential nucleic acid binding motifs clustered at one end, including an S1 domain near the C-terminus that displays considerable structural flexibility. Tex binds nucleic acids, with a preference for single-stranded RNA, and the Tex S1 domain is required for this binding activity. Point mutants further demonstrate that the primary nucleic acid binding site corresponds to a surface of the S1 domain. Sequence alignment and modeling indicate that the eukaryotic Spt6 transcription factor adopts a similar core structure. Structural analysis further suggests that the RNA polymerase and nucleosome interacting regions of Spt6 flank opposite sides of the Tex-like scaffold. Therefore, the Tex structure may represent a conserved scaffold that binds single-stranded RNA to regulate transcription in both eukaryotic and prokaryotic organisms. Published by Elsevier Ltd.

【 授权许可】

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