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Journal of Biomedical Research | Volume: 29

November 19-20, 2018 | Paris, France

Molecular Biology, Tissue Science and Regenerative Medicine

International Conference on

Joint Event

World Heart Congress

The centres of premeltons signal the beginning and ends of genes

Henry M Sobell

University of Rochester, USA

remeltons are examples of emergent structures (i.e.,

structural solitons) that arise spontaneously in DNA due

to the presence of nonlinear excitations in its structure. They

are of two kinds: B-B or A-A premeltons form at specific

DNA-regions to nucleate site-specific DNA melting. These are

stationary and being globally nontopological, undergo breather

motions that allow drugs and dyes to intercalate into DNA. B-A

or A-B premeltons, on the other hand, are mobile and being

globally topological, act as phase-boundaries transforming B-

into A- DNA during the structural phase-transition. They are

not expected to undergo breather-motions. A key feature of

both types of premeltons is the presence of an intermediate

structural-form in their central regions (proposed as being a

transition-state intermediate in DNA-melting and in the B-

to A- transition), which differs from either A- DNA or B- DNA

called beta-DNA, this is both metastable and hyperflexible

and contains an alternating sugar-puckering pattern along

the polymer-backbone combined with the partial-unstacking

(in its lower energy-forms) of every other base-pair. Beta-

DNA is connected to either B- or to A- DNA on either side by

boundaries possessing a gradation of nonlinear structural-

change, these being called the kink and the antikink regions.

The presence of premeltons in DNA leads to a unifying theory

to understand much of DNA physical-chemistry and molecular-

biology. The premeltons are predicted to define the 5’ and 3’

ends of genes in naked-DNA and DNA in active-chromatin,

this having important implications for understanding physical

aspects of the initiation, elongation and termination of RNA-

synthesis during transcription. For these and other reasons,

the model will be of broader interest to the general audience

working in these areas. The model explains a wide variety of

data and carries within it several experimental predictions all

readily testables as will be described in my talk.

Molecular Biology & Heart Congress 2018, Volume 29

DOI: 10.4066/biomedicalresearch-C8-023