ISSN:
1399-0047
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
Repeat units based on the telomeric sequence of the ciliated protozoan Tetrahymena, d(C4A2)2, have been crystallized. Cytosine-rich DNA stretches are known to reside in telomeres and centromeres of eukaryotic chromosomes, playing crucial roles in the structural stability of the chromosome in addition to their connection with cancer and aging. Preliminary investigations on the telomeric repeat sequence C4A2C4A2 from CD studies and X-ray crystal data suggest it to be a right-handed interdigitated tetraplex structure with hemiprotonated C\cdotC+ base pairs. The molecules appear to be packed one on top of another forming a discontinuous helix along c simulating a poly-C fibre, an arrangement which maximizes the number of cytosines stacked.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0907444901005054
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