Solution-state structure of a long-loop G-quadruplex formed within promoters of Plasmodium falciparum B var genes

Juribašić Kulcsár, Marina (author), Gabelica, Valérie (author), Plavec, Janez (author)

We report the high-resolution NMR solution-state structure of an intramolecular G-quadruplex with a diagonal loop of ten nucleotides. The G-quadruplex is formed by a 34-nt DNA sequence, d[CAG$_3$T$_2$A$_2$G$_3$TATA$_2$CT$_3$AG$_4$T$_2$AG$_3$T$_2$], named UpsB-Q-1. This sequence is found within promoters of the var genes of Plasmodium falciparum, which play a key role in malaria pathogenesis and evasion of the immune system. The [3+1]-hybrid G-quadruplex formed under physiologically relevant conditions exhibits a unique equilibrium between two structures, both stabilized by base stacking and non-canonical hydrogen bonding. Unique equilibrium of the two closely related 3D structures originates from a North-South repuckering of deoxyribose moiety of residue T27 in the lateral loop. Besides the 12 guanines involved in three G-quartets, most residues in loop regions are involved in interactions at both G-quartet-loop interfaces.

• Language: English
• Keywords: G-quadruplex, nuclear magnetic resonance, long loop, loop interactions, Plasmodium falciparum
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 11 str.
• Numbering: Vol. 30, iss. 36, art. e202401190
• PID: 20.500.12556/RUL-159456
• UDC: 577
• ISSN on article: 1521-3765
• DOI: 10.1002/chem.202401190
• COBISS.SI-ID: 201336579
• Publication date in RUL: 10.07.2024

Record is a part of a journal

• Title: Chemistry : a European journal
• Shortened title: Chemistry
• Publisher: Wiley, Chemistry Europe
• ISSN: 1521-3765
• COBISS.SI-ID: 21813253

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.

Secondary language

• Language: Slovenian
• Keywords: biokemija, g-kvadrupleksi, NMR, 3D strukture, malarija