Book of Abstracts: Albany 2003

category image Albany 2003
Conversation 13
Abstract Book
June 17-21 2003

On the Structural and Kinematical Peculiarities of DNA-Vitamin D Complexes as Revealed by Atomic Force Microscopy and Molecular Mechanics

In its genomic action, vitamin D binds to a specific receptor which is a member of the steroid hormone receptor superfamily. The vitamin D receptor (VDR) forms heterodimers with retinoid X receptors (RXRs), and the dimer interacts then with its cognate binding site, termed vitamin D response element (VDRE), to affect the transcription of target genes. Recent studies have identified novel sequence motifs for VDREs as well as novel protein-protein interactions involving the VDR. Thus, the research on the control of gene transcription by vitamin D reveals examples of molecular interplay between transcriptional regulatory pathways and provides new insight into the molecular mechanism of action of vitamin D (1). However, to the best of our knowledge there is no detailed study concerning direct interaction between DNA molecules and vitamin D group to date. In the present study, we report on the structural and kinematical peculiarities of DNA-vitamin D complexes, as revealed by atomic force, fluorescence and coherent phase microscopy, as well as molecular mechanics modeling. The dependence of intermolecular interactions on the vitamin nature and on the existence of metal cations (II) was revealed. A structural model is introduced, and a new approach for targeted gene delivery (vitafection), using fat soluble vitamins (A, D, E, and K), is presented.

A. S. Elkady1,2,*
R. I. Zhdanov2

1Physics Department Moscow State University GSP-2, Leninski Gori Moscow 119992, Russia Phone: 7(095)939-2959 Fax: 7(095)939-2988 2Institute of Biomedical Chemistry
RAS, 10 Pogodinskaya st.
Moscow 119121, Russia
Phone: 7(095)2959
Fax: 7(095)9328820

References and Footnotes
  1. Rene St-Arnaud, G. Antonio Candeliere, and Shoukat Dedhar, Frontiers in Bioscience 1, d177-188, (1996).