Inhomogeneous DNA: Conducting exons and insulating introns

Abstract

Parts of DNA sequences known as exons and introns play very different roles in coding and storage of genetic information. Here we show that their conducting properties are also very different. Taking into account long-range correlations among four basic nucleotides that form double-stranded DNA sequence, we calculate electron localization length for exon and intron regions. Analyzing different DNA molecules, we obtain that the exons have narrow bands of extended states, unlike the introns where all the states are well localized. The band of extended states is due to a specific form of the binary correlation function of the sequence of basic DNA nucleotides.

Effect of Anderson Localization on Auger Destruction of DNA

“…The theory of Auger destruction of DNA has been modified taking into account the localized and delocalized electron states in DNA owing to the correlated disorder in a sequence of nucleotides. According to the modified theoretical model of Auger destruction, the dominant ratio of delocalized states to localized states in exon compared to intron results in stronger radiation resistance of exons to ionized irradiation causing the Auger-cascade process than the radiation resistance of introns.One of the interesting and important applications of the localization theory developed for one-dimensional systems [1][2][3][4] is related to conductivity of DNA molecules [4][5][6]. The electronic structure of DNA represents a very interesting problem by itself.…”

“…One of the interesting and important applications of the localization theory developed for one-dimensional systems [1][2][3][4] is related to conductivity of DNA molecules [4][5][6]. The electronic structure of DNA represents a very interesting problem by itself.…”

“…Studies of long-range correlation in nucleotide structure resulted in proclamation that DNA was aperiodic crystal with long-range correlation [9]. In the work [4][5][6] in the framework of the two-channel tight-binding model it was shown how the information coded in a sequence of nucleotides may affect the localization length (therefore, the resistivity) of a given segment of a DNA molecule. The principal results of these work are that for the most of the energies the localization length inside the exon (the coding regions of DNA) region exceeds by order of magnitude the localization length inside the intron region (the noncoding regions of DNA).…”

Quantum effects and magnetism in the spatially distributed DNA molecules

“…[22,23]. The length of a genetic mutation is known to be relatively short (about 10 base pairs) as compared to the length of a gene (10 3 -10 6 base pairs).…”

“…According to Ref. [22], the exons (the parts where the genetic information is written) have narrow bands of extended (practically delocalized) states. At the same time, for the introns (the parts without apparent information for protein synthesis, the DNA "dark matter") all the states are characterized by welllocalized electron wave functions.…”