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From Proteopedia
THE UNUSUAL STRUCTURE OF THE HUMAN CENTROMERE (GGA)2 MOTIF: UNPAIRED GUANOSINE RESIDUES STACKED BETWEEN SHEARED G(DOT)A PAIRS
Overview
The centromere of human chromosomes contains multiple repeats of the DNA sequence d(TGGAA)n. This sequence has the interesting property of pairing with itself to form stable duplexes. We have determined the solution structure of the unusual DNA duplex 5'-TGGAATGGAA:TGGAATGGAA-3' at atomic resolution. The duplex contains unpaired staggered guanosine residues, which co-stack by intercalation between sheared G.A and A.G base-pairs to form an interesting new structural motif, the GA-bracketed G-stack. The TGGAA repeat unit contains six "steps", four of which are not Watson-Crick base-pairs.
About this Structure
Full crystallographic information is available from OCA.
Reference
The unusual structure of the human centromere (GGA)2 motif. Unpaired guanosine residues stacked between sheared G.A pairs., Chou SH, Zhu L, Reid BR, J Mol Biol. 1994 Dec 2;244(3):259-68. PMID:7966337 Page seeded by OCA on Fri May 2 09:24:35 2008
