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Sequence-Dependent Persistence Length of Long DNA.

ABSTRACT: Using a high-throughput genome-mapping approach, we obtained circa 50 million measurements of the extension of internal human DNA segments in a 41??nm×41??nm nanochannel. The underlying DNA sequences, obtained by mapping to the reference human genome, are 2.5-393 kilobase pairs long and contain percent GC contents between 32.5% and 60%. Using Odijk's theory for a channel-confined wormlike chain, these data reveal that the DNA persistence length increases by almost 20% as the percent GC content increases. The increased persistence length is rationalized by a model, containing no adjustable parameters, that treats the DNA as a statistical terpolymer with a sequence-dependent intrinsic persistence length and a sequence-independent electrostatic persistence length.

SUBMITTER: Chuang HM

PROVIDER: S-EPMC5839665 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Sequence-Dependent Persistence Length of Long DNA.

Chuang Hui-Min HM Reifenberger Jeffrey G JG Cao Han H Dorfman Kevin D KD

Physical review letters 20171129 22

Using a high-throughput genome-mapping approach, we obtained circa 50 million measurements of the extension of internal human DNA segments in a 41 nm×41 nm nanochannel. The underlying DNA sequences, obtained by mapping to the reference human genome, are 2.5-393 kilobase pairs long and contain percent GC contents between 32.5% and 60%. Using Odijk's theory for a channel-confined wormlike chain, these data reveal that the DNA persistence length increases by almost 20% as the percent GC content i ...[more]

PMID: 29286779

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