Transposable elements as architects of fungal genomes: tracking TE dynamics from decades to a billion years

SemIDEEV
 10/10/2025
 12:00:00
 Tobias BARIL, Université de Neuchâtel
 IDEEV - Salle Rachel Carlson

Transposable elements (TEs) are abundant, diverse, and persistent components of eukaryotic genomes. Increasing evidence suggests that TEs can drive host adaptation, prompting a fundamental question in evolutionary biology: to what extent has the complexity of eukaryotic life been shaped by TE activity? To address this, I investigate TE dynamics across multiple biological scales—from populations to entire kingdoms—while developing scalable, species-agnostic tools that enable such analyses. At the population level, I focus on the fungal wheat pathogen Zymoseptoria tritici, which provides exceptional resolution for studying recent TE evolution thanks to dense global sampling and a well-characterised timeline of range expansion. At broader evolutionary scales, I examine how TEs persist over millions of years despite often imposing fitness costs and threatening genome integrity. Using controlled phylogenetic frameworks, I incorporate variation in host suppression mechanisms, life-history traits, and horizontal transposon transfer (HTT) to understand the interactions that underpin the widespread persistence of TEs across eukaryotic genomes. Fungi offer an ideal system for these investigations, with over 4,300 genomes spanning nearly one billion years of evolution. This diversity opens the door to evaluating long-standing assumptions about TE evolution beyond a handful of model systems. By combining cross-scale evolutionary analyses with the development of accessible tools, my goal is to build a foundation on which we can determine whether TEs are simply selfish elements, or hidden architects responsible for driving genomic novelty across eukaryotes.

More information : https://tobybaril.github.io