178
Views
2
CrossRef citations to date
0
Altmetric
Research Article

Metal sensitive and DNA concentration dependent structural rearrangement of short oligonucleotide into large suprastructures

, , , &
Pages 2211-2218 | Received 02 Apr 2018, Accepted 17 May 2018, Published online: 28 Dec 2018
 

Abstract

Formation of higher order structures, such as G-quadruplexes and G-quadruplex based large suprastructures into long G-wires and liquid crystals is promising elements for use in healthcare for drug delivery as they are mechanically and thermally stable. In this study, we studied the structures of short 11-mer oligonucleotide 5′-G2AG5AG2-3′(11Pu) which is observed in 3′-UTR region of c-jun protooncogene. We used circular dichroism, UV-thermal melting, native gel electrophoresis and atomic force microscopy to determine the structure of 11Pu. CD results showed that 11Pu formed a mixed G-quadruplex in the presence of Na+ with and without Mg2+, while it formed a parallel G-quadruplex in the presence of 100 mM K+ with or without Mg2+. Cation selectivity in inducing the formation of large superstructures was observed in the presence of 100 mM K+ with 10 mM Mg2+. On the contrary, 10 mM Ca2+ did not induce the suprastructures. It was further demonstrated that Mg2+ at low concentration induced a parallel G-quadruplex of 11Pu, whereas at 10 mM Mg2+ induced a large suprastructure. AFM Images showed that 11Pu formed a G-wire, a liquid crystals and a crystalline lattice depending on the concentration of 11Pu and Mg2+. These insights may be employed to design G quadruplex-based nanowires for targeted drug delivery as well as interesting candidates for molecular nanowires.

Communicated by Ramaswamy H. Sarma

Acknowledgement

The timely help from Dr. Anupama Kumari, IGIB, CSIR is greatly acknowledged in AFM measurements.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the research grant of “Department of Science and Technology (DST)”, Govt of India [No. SR/FT/LS-21/2010].

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.