2aje
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Solution structure of the Arabidopsis thaliana telomeric repeat-binding protein DNA binding domain
OverviewOverview
The double-stranded telomeric repeat-binding protein (TRP) AtTRP1 is, isolated from Arabidopsis thaliana. Using gel retardation assays, we, defined the C-terminal 97 amino acid residues, Gln464 to Val560, (AtTRP1(464-560)), as the minimal structured telomeric repeat-binding, domain. This region contains a typical Myb DNA-binding motif and a, C-terminal extension of 40 amino acid residues. The monomeric, AtTRP1(464-560) binds to a 13-mer DNA duplex containing a single repeat of, an A.thaliana telomeric DNA sequence (GGTTTAG) in a 1:1 complex, with a, K(D) approximately 10(-6)-10(-7) M. Nuclear magnetic resonance (NMR), examination revealed that the solution structure of AtTRP1(464-560) is a, novel four-helix tetrahedron rather than the three-helix bundle structure, found in typical Myb motifs and other TRPs. Binding of the 13-mer DNA, duplex to AtTRP1(464-560) induced significant chemical shift perturbations, of protein amide resonances, which suggests that helix 3 (H3) and the, flexible loop connecting H3 and H4 are essential for telomeric DNA, sequence recognition. Furthermore, similar to that in hTRF1, the, N-terminal arm likely contributes to or stabilizes DNA binding. Sequence, comparisons suggested that the four-helix structure and the involvement of, the loop residues in DNA binding may be features unique to plant TRPs.
About this StructureAbout this Structure
2AJE is a Single protein structure of sequence from Arabidopsis thaliana. Full crystallographic information is available from OCA.
ReferenceReference
Solution structure of the Arabidopsis thaliana telomeric repeat-binding protein DNA binding domain: a new fold with an additional C-terminal helix., Sue SC, Hsiao HH, Chung BC, Cheng YH, Hsueh KL, Chen CM, Ho CH, Huang TH, J Mol Biol. 2006 Feb 10;356(1):72-85. Epub 2005 Nov 22. PMID:16337232
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