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Title: Pairing statistics and melting of random DNA oligomers: Finding your partner in superdiverse environments
Understanding of the pairing statistics in solutions populated by a large number of distinct solute species with mutual interactions is a challenging topic, relevant in modeling the complexity of real biological systems. Here we describe, both experimentally and theoretically, the formation of duplexes in a solution of random-sequence DNA (rsDNA) oligomers of lengthL= 8, 12, 20 nucleotides. rsDNA solutions are formed by 4Ldistinct molecular species, leading to a variety of pairing motifs that depend on sequence complementarity and range from strongly bound, fully paired defectless helices to weakly interacting mismatched duplexes. Experiments and theory coherently combine revealing a hybridization statistics characterized by a prevalence of partially defected duplexes, with a distribution of type and number of pairing errors that depends on temperature. We find that despite the enormous multitude of inter-strand interactions, defectless duplexes are formed, involving a fraction up to 15% of the rsDNA chains at the lowest temperatures. Experiments and theory are limited here to equilibrium conditions.  more » « less
Award ID(s):
2005212
PAR ID:
10496614
Author(s) / Creator(s):
; ; ; ; ; ; ;
Corporate Creator(s):
Editor(s):
Shakhnovich, Eugene I.
Publisher / Repository:
PLOS
Date Published:
Journal Name:
PLOS Computational Biology
Edition / Version:
NA
Volume:
18
Issue:
4
ISSN:
1553-7358
Page Range / eLocation ID:
e1010051
Subject(s) / Keyword(s):
DNA, liquid crystals, random, oligomer
Format(s):
Medium: X Size: 3Mb Other: NA
Size(s):
3Mb
Sponsoring Org:
National Science Foundation
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