Evolution of telomeres

Our aim is to gain understanding into the plasticity and evolution of eukaryotes at the level of the molecular structures that ensure the protection of their chromosome ends.

In eukaryotes where telomeres are elongated by telomerase, the telomeric DNA strand running toward the 3’ end is generally composed of repeats of a short motif (“telomeric motif”) carrying consecutive guanines. Telomeric DNA associates (directly or indirectly) with a set of proteins specific of telomeres that are essential for telomere protection and regulation. The architecture of telomeres (DNA sequence, DNA structures and associated proteins,) in eukaryotes present common features modulated by species-specific features and constitute a fascinating example of the unity and diversity of life.

Our new projects are aimed at understanding two main aspects of telomere evolution, through the study of several eukaryote models:

1) How telomeric sequences and proteins that specifically associated to them coevolved;

2) Whether and how a single-stranded DNA-binding complex RPA-like (acting genome-wide and lacking DNA sequence specificity) might have evolved toward complexes that specifically bind to telomeric DNA.

We have already contributed to studies about telomere evolution in the framework of two international collaborations with the team of Maria Cano (São Paulo State University).(doi: 10.1016/j.bbagen.2020.129607) and the team of Dorothy Shippen (Texas A&M University) (doi: 10.1534/genetics.120.303222).