Complex pretransitional solution dynamics and LC behaviour of $\mathrm{d(G_4C_2)}$ and $\mathrm{d(G_4C_2)_4}$ DNA sequences

Potrč, Melani (author), Čokor, Elena (author), Drevenšek Olenik, Irena (author), Spindler, Lea (author)

Beyond the well-known double-helix structure, guanine-rich DNA sequences can form higher-order structures, known as DNA quadruplexes. These structures play an important role in gene regulation and are associated with certain neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Although the LC phases of double-stranded DNA have been extensively studied, the self-assembly and LC behaviour of DNA quadruplexes remain largely unexplored. In this study, we investigated the DNA sequences d(G$_4$C$_2$) and d(G$_4$C$_2$)$_4$, which exhibit supramolecular assembly. The focus of our study was to examine the effect of DNA concentration on the dynamics of DNA quadruplexes in the pretransitional I $\to$ LC region and to assess their ability to form LC phases at higher concentrations – conditions that better represent physiological environments. Measurements were performed using dynamic light scattering (DLS) and polarisation optical microscopy (POM). DLS was employed to study the dynamics of DNA quadruplexes in the pretransitional region, while POM was used to identify mesophases at higher concentrations. Our results indicate that the d(G$_4$C$_2$) and d(G$_4$C$_2$)$_4$ sequences behave like typical polyelectrolytes and exhibit the potential to form LC phases.

• Language: English
• Keywords: liquid crystals, polarised optical microscopy, dynamic light scattering, DNA, DNA-quadruplexes, polyelectrolytes, chromonics
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: Str. 123-130
• Numbering: Vol. 53, iss. 1
• PID: 20.500.12556/RUL-186166
• UDC: 538.9
• ISSN on article: 0267-8292
• DOI: 10.1080/02678292.2026.2622530
• COBISS.SI-ID: 269188355
• Publication date in RUL: 28.08.2026

Record is a part of a journal

• Title: Liquid crystals
• Shortened title: Liq. cryst.
• Publisher: Taylor & Francis
• ISSN: 0267-8292
• COBISS.SI-ID: 1690628

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: tekoči kristali, polarizacijska optična mikroskopija, dinamično sipanje svetlobe, DNK, DNK kvadrupleksi, polielektroliti

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P1-0192
• Name: Svetloba in snov

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P1-0403
• Name: Računsko intenzivni kompleksni sistemi