کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1960200 1057952 2006 15 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The Transition between the B and Z Conformations of DNA Investigated by Targeted Molecular Dynamics Simulations with Explicit Solvation
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
The Transition between the B and Z Conformations of DNA Investigated by Targeted Molecular Dynamics Simulations with Explicit Solvation
چکیده انگلیسی

The transition between the B and Z conformations of double-helical deoxyribonucleic acid (DNA) belongs to the most complex and elusive conformational changes occurring in biomolecules. Since the accidental discovery of the left-handed Z-DNA form in the late 1970s, research on this DNA morphology has been engaged in resolving questions relative to its stability, occurrence, and function in biological processes. While the occurrence of Z-DNA in vivo is now widely recognized and the major factors influencing its thermodynamical stability are largely understood, the intricate conformational changes that take place during the B-to-Z transition are still unknown at the atomic level. In this article, we report simulations of this transition for the 3′-(CGCGCG)-5′ hexamer duplex using targeted molecular dynamics with the GROMOS96 force field in explicit water under different ionic-strength conditions. The results suggest that for this oligomer length and sequence, the transition mechanism involves: 1), a stretched intermediate conformation, which provides a simple solution to the important sterical constraints involved in this transition; 2), the transient disruption of Watson-Crick hydrogen-bond pairing, partly compensated energetically by an increase in the number of solute-solvent hydrogen bonds; and 3), an asynchronous flipping of the bases compatible with a zipperlike progression mechanism.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: - Volume 91, Issue 8, 15 October 2006, Pages 2976–2990
نویسندگان
, , ,