This article has an erratum: [erratum]
Volume 95, Number 4, August 2011
|Number of page(s)||4|
|Section||Interdisciplinary Physics and Related Areas of Science and Technology|
|Published online||05 August 2011|
Type II DNA: When the interfacial energy becomes negative
Institute of Physics - Bhubaneswar 751 005, India
Accepted: 6 July 2011
An important step in transcription of a DNA base sequence to a protein is the initiation from the exact starting point, called promoter region. We propose a physical mechanism for identification of the promoter region, which relies on a new classification of DNAs into two types, Type I and Type II, like superconductors, depending on the sign of the energy of the interface separating the zipped and the unzipped phases. This is determined by the energies of helical ordering and stretching over two independent length scales. The negative interfacial energy in Type II DNA leads to domains of helically ordered state separated by defect regions, or blobs, enclosed by the interfaces. The defect blobs, pinned by non-coding promoter regions, would be physically distinct from all other types of bubbles. We also show that the order of the melting transition under a force is different for Type I and Type II.
PACS: 87.14.gk – DNA / 87.15.Zg – Phase transitions / 74.20.De – Phenomenological theories (two-fluid, Ginzburg-Landau, etc.)
© EPLA, 2011
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.