2AJE

Solution structure of the Arabidopsis thaliana telomeric repeat-binding protein DNA binding domain

Summary for 2AJE

• Entry DOI: 10.2210/pdb2aje/pdb
• Related: 1BA5 1FEX 1IGN 1MSF 1W0T 1W0U
• NMR Information: BMRB: 6727
• Descriptor: telomere repeat-binding protein (1 entity in total)
• Functional Keywords: telomere, dna-binding, trp, myb motif, dna binding protein
• Biological source: Arabidopsis thaliana (thale cress)
• Total number of polymer chains: 1
• Total formula weight: 12320.98

Authors

Hsiao, H.H.,Sue, S.C.,Chung, B.C.,Cheng, Y.H.,Huang, T.H. (deposition date: 2005-08-01, release date: 2006-07-04, Last modification date: 2024-05-29)

Primary citation

Sue, S.C.,Hsiao, H.H.,Chung, B.C.,Cheng, Y.H.,Hsueh, K.L.,Chen, C.M.,Ho, C.H.,Huang, T.H.
Solution structure of the Arabidopsis thaliana telomeric repeat-binding protein DNA binding domain: a new fold with an additional C-terminal helix
J.Mol.Biol., 356:72-85, 2006

PubMed Abstract: 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.

PubMed: 16337232
DOI: 10.1016/j.jmb.2005.11.009

Experimental method

SOLUTION NMR