Centromeric origin of megabase-scale Arabidopsis interstitial telomeric repeat domains
Year: 2026
Type: preprint
Abstract: The mechanisms underlying the emergence of new DNA repeat classes remain poorly understood. One such example is the formation of interstitial telomeric repeat (ITR) domains commonly viewed as telomere-fossil byproducts of chromosome rearrangements. Here, we report that in Arabidopsis thaliana , ITRs arise from centromeres as centromeric-telomeric mosaic satellites that expand into higher-order structures via in situ amplification. Long-read sequencing of mutation accumulation lines and forward simulations of mutational processes confirmed the propensity of centromeres to form telomeric motifs. During establishment, ITRs adopt an atypical chromatin state that excludes CENH3 incorporation, thereby enabling escape from the functional constraints of centromere identity. Accordingly, a pangenomic survey of natural accessions showed that ITRs vary abruptly and independently of telomere length, notably through transposon-associated block duplications. These findings identify centromeres as major sources of telomeric sequences and an original route for the emergence of new DNA satellite types.
Institutions: Centre National de la Recherche Scientifique, Inserm, Université Paris Sciences et Lettres, Université Paris-Saclay, Sorbonne Université, Institut de Biologie Paris-Seine, Institut de Biologie de l'École Normale Supérieure, Développement Adaptation et Vieillissement, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Institut des Sciences des Plantes de Paris Saclay, Université Paris Diderot, Biologie Computationnelle, Quantitative et Synthétique, University of Cambridge, Max Planck Institute for Biology, Central European Institute of Technology, Masaryk University, Central European Institute of Technology – Masaryk University
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7160932239