Thanks to everyone involved and to our funding agencies @fr-genomics.bsky.social @agencerecherche.bsky.social @frm-officiel.bsky.social
5/5

• These chromosome ends are eliminated during development by an unexpected mechanism, independent of the endonuclease previously thought to mediate all transposon elimination.
4/5

• Chromosome ends harbor a novel clade of Helitrons, with 9–10 kb transposase ORFs under purifying selection, that have remained active across all P. aurelia lineages.
3/5

Highlights:
•Chromosome-scale germline genome assemblies for 7 Paramecium aurelia species, including a telomere-to-telomere assembly for P. tetraurelia.

•Tiny (300kb–1.2Mb) and numerous (~160) germline chromosomes showing the highest recombination rate ever reported for a eukaryote (420 cM/Mb).
2/5

Thanks to all the co-authors, and congrats to
@oliviacharmant.bsky.social and Caridad!
Thanks to @ijmonod.bsky.social
@agencerecherche.bsky.social @frm-officiel.bsky.social
#EURGENEPARIS @upcite.bsky.social for support.

Bonus: The slicer activity of the small RNA-binding protein Ptiwi09 is required for the removal of the passenger strand, similarly to the Tetrahymena Twi1p
4/5
www.cell.com/cell/fulltex...

Key findings:
• Small RNA dynamics during sexual events with unprecedented resolution
• A histone methyltransferase-independent function of PRC2 in the degradation of small RNAs
• The PRC2 cofactor Rf4 is required for the interaction between the small RNA-binding protein Ptiwi09 and Gtsf1
3/5

Following our previous work on the role of Gtsf1 in small RNA degradation, we explored the role of PRC2 in this process.
2/5
doi.org/10.1093/nar/...

🔬 This event is organized by @sandraduharcourt.bsky.social , @daphne-cabianca.bsky.social , Germano Cecere , Pierre-Antoine Defossez, Ines Drinnenberg, @rodvilla.bsky.social