1KIX

Dimeric Structure of the O. nova Telomere End Binding Protein Alpha Subunit with Bound ssDNA

Summary for 1KIX

• Entry DOI: 10.2210/pdb1kix/pdb
• Related: 1jb7 1k8g 1otc
• Descriptor: 5'-D(*T*TP*TP*TP*GP*GP*GP*G)-3', Telomere-Binding Protein alpha Subunit, SULFATE ION, ... (4 entities in total)
• Functional Keywords: telomere binding protein, dna-protein interactions, single stranded dna, ssdna, dna binding protein-dna complex, dna binding protein/dna
• Biological source: Sterkiella nova
• Cellular location: Nucleus: P29549
• Total number of polymer chains: 2
• Total formula weight: 58849.06

Authors

Peersen, O.B.,Ruggles, J.A.,Schultz, S.C. (deposition date: 2001-12-03, release date: 2002-02-22, Last modification date: 2023-08-16)

Primary citation

Peersen, O.B.,Ruggles, J.A.,Schultz, S.C.
Dimeric structure of the Oxytricha nova telomere end-binding protein alpha-subunit bound to ssDNA.
Nat.Struct.Biol., 9:182-187, 2002

PubMed Abstract: Telomeres are the specialized protein--DNA complexes that cap and protect the ends of linear eukaryotic chromosomes. The extreme 3' end of the telomeric DNA in Oxytricha nova is bound by a two-subunit sequence-specific and 3' end-specific protein called the telomere end-binding protein (OnTEBP). Here we describe the crystal structure of the alpha-subunit of OnTEBP in complex with T4G4 single-stranded telomeric DNA. This structure shows an (alpha--ssDNA)2 homodimer with a large approximately 7,000 A2 protein--protein interface in which the domains of alpha are rearranged extensively from their positions in the structure of an alpha--beta--ssDNA ternary complex. The (alpha--ssDNA)2 complex can bind two telomeres on opposite sides of the dimer and, thus, acts as a protein mediator of telomere--telomere associations. The structures of the (alpha--ssDNA)2 dimer presented here and the previously described alpha--beta--ssDNA complex demonstrate that OnTEBP forms multiple telomeric complexes that potentially mediate the assembly and disassembly of higher order telomeric structures.

PubMed: 11836536

Experimental method

X-RAY DIFFRACTION (2.7 Å)