Crystal Structure and RNA Binding of the Tex Protein from Pseudomonas aeruginosa
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 Angstroms 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.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
- Sponsoring Organization:
- Doe - Office Of Science
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 959729
- Report Number(s):
- BNL-82715-2009-JA; JMOBAK; TRN: US201016%%873
- Journal Information:
- Journal of Molecular Biology, Vol. 377, Issue 5; ISSN 0022-2836
- Country of Publication:
- United States
- Language:
- English
Similar Records
Crystal Structures of the S. cerevisiae Spt6 Core and C-Terminal Tandem SH2 Domain
Crystal structure of the flavoenzyme PA4991 from Pseudomonas aeruginosa