2026-04-28T15:40:35Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/57842024-07-25T07:31:53Zcom_10259_9476com_10259.4_106com_10259_2604col_10259_9477

Kinky DNA in solution: Small-angle-scattering study of a nucleosome positioning sequence Schindler, Torben González, Adrián Boopathi, Ramachandran Marty Roda, Marta Romero Santacreu, Lorena Wildes, Andew R. Porcar, Lionel Martel, Anne Theodorakopoulos, Nikos Cuesta López, Santiago Angelov, Dimitar Unruh, Tobias Peyrard, Michel Física Physics 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. Spanish Ministry of Economy, Industry and Competitiveness (BES-2013-065453, EEBB-I-2015-09973, FIS2012-38827). S.C.L. and UC-154 are grateful for the support of Junta de Castilla y Leon (Spain) Nanofibersafe BU079U16. D.A. acknowledges funding from the Agence Nationale de la Recherche through ANR-12-BSV5-0017-01 “Chrome” and ANR-17-CE11-0019-03 “Chrom3D” grants. N.T. acknowledges support by the project Advanced Materials and Devices (MIS 5002409, Competitiveness, Entrepreneurship and Innovation, NSRF 2014-2020) cofinanced by Greece and the European Regional Development Fund. 2021-05-25T10:06:10Z 2021-05-25T10:06:10Z 2018-10 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion 2470-0045 http://hdl.handle.net/10259/5784 10.1103/PhysRevE.98.042417 2470-0053 eng Physical Review E. 2018, V. 98, n. 4, 042417 https://doi.org/10.1103/PhysRevE.98.042417 info:eu-repo/grantAgreement/MINECO/BES-2013-065453 info:eu-repo/grantAgreement/MINECO/EEBB-I-2015-09973 info:eu-repo/grantAgreement/MINECO/FIS2012-38827 info:eu-repo/grantAgreement/JCyL/BU079U16 info:eu-repo/semantics/openAccess application/pdf American Physical Society