RT Journal
A1 Chantzi, Nikol
A1 Nayak, Akshatha
A1 Baltoumas, Fotis A.
A1 Aplakidou, Eleni
A1 Liew, Shiau Wei
A1 Galuh, Jesslyn Elvaretta
A1 Patsakis, Michail
A1 Montgomery, Austin
A1 Moeckel, Camille
A1 Mouratidis, Ioannis
A1 Sazed, Saiful Arefeen
A1 Guiblet, Wilfried
A1 Karmiris-Obratański, Panagiotis
A1 Wang, Guliang
A1 Zaravinos, Apostolos
A1 Vasquez, Karen M.
A1 Kwok, Chun Kit
A1 Pavlopoulos, Georgios A.
A1 Georgakopoulos-Soares, Ilias
T1 Quadrupia provides a comprehensive catalog of G-quadruplexes across genomes from the tree of life
JF Genome Research 
JO Genome Research 
YR 2025 
FD November 01 
VO 35 
IS 11 
SP 2578 
OP 2600 
DO 10.1101/gr.279790.124 
UL http://genome.cshlp.org/content/35/11/2578.abstract 
AB G-quadruplex DNA structures exhibit a profound influence on essential biological processes, including transcription, replication, telomere maintenance, and genomic stability. These structures have demonstrably shaped organismal evolution. However, a comprehensive, organism-wide G-quadruplex map encompassing the diversity of life has remained elusive. Here, we introduce Quadrupia, the most extensive and well-characterized G-quadruplex database to date, facilitating the exploration of G-quadruplex structures across the evolutionary spectrum. Quadrupia has identified G-quadruplex sequences in 108,449 reference genomes, with a total of 140,181,277 G-quadruplexes. The database also hosts a collection of 319,784 G-quadruplex clusters of 20 or more members, annotated by taxonomic distributions, multiple sequence alignments, profile hidden Markov models, and cross-references to G-quadruplex 3D structures. Examination of G-quadruplexes across functional genomic elements in different taxa indicates preferential orientation and positioning, with significant differences between individual taxonomic groups. For example, we find that G-quadruplexes in bacteria with a single replication origin display profound preference for the leading orientation. Finally, we experimentally validate the most frequently observed G-quadruplexes using CD-spectroscopy, UV melting, and fluorescent-based approaches.