Por favor, use este identificador para citar o enlazar este ítem: http://hdl.handle.net/10259/5784
Kinky DNA in solution: Small-angle-scattering study of a nucleosome positioning sequence
Physical Review E. 2018, V. 98, n. 4, 042417
American Physical Society
Fecha de publicación
DNA is a flexible molecule, but the degree of its flexibility is subject to debate. The commonly-accepted persistence length of lp ≈ 500Å is inconsistent with recent studies on short-chain DNA that show much greater flexibility but do not probe its origin. We have performed x-ray and neutron small-angle scattering on a short DNA sequence containing a strong nucleosome positioning element and analyzed the results using a modified Kratky-Porod model to determine possible conformations. Our results support a hypothesis from Crick and Klug in 1975 that some DNA sequences in solution can have sharp kinks, potentially resolving the discrepancy. Our conclusions are supported by measurements on a radiation-damaged sample, where single-strand breaks lead to increased flexibility and by an analysis of data from another sequence, which does not have kinks, but where our method can detect a locally enhanced flexibility due to an AT domain.
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