8/ Next, we investigated the link of ERS to other members of the CSP. We hypothesized that ERS act downstream of CYCLOPS.

We could show that ERS are induced by CYCLOPs in transactivation assays in N. bethamiana. @tatiana-vernie.bsky.social

7/ We hypothesized that ERS induce the so-called "infectosome" that includes LIN and is required for the formation of symbiosis-specific intracellular structures in angiosperms.

We could confirm an induction of LIN by ERS in transactivation assays in N. bethamiana @tatiana-vernie.bsky.social

6/ Thus, we named these transcription factors "Ethylene response factor required for symbiosis" (ERS).

We then asked how ERS are regulating different types of endosymbioses?

5/ We then generated double mutants of two paralogs of these TFs in #MyMarchantia and investigated their function during AMS.

We found that the double mutants were completely deficient in AMS - similarly to other members of the common symbiosis pathway (CSP; see also Vernie et al 2025, PNAS).

4/ To functionally dissect conserved gene modules, we then cross-referenced RNAseq data from C. fissa during ErM and #MyMarchantia during arbuscular mycorrhizal symbiosis (AMS).

We found a group of ethylene response transcription factors that were upregulated during both types of endosymbioses.

3/ We aimed to understand how different types of intracellular symbioses diversified during land plant evolution.

Initially, @leocastanedo.bsky.social, studied Ericoid mycorrhizae (ErM) in the leafy liverwort Calypogeia fissa

Nice dinner in best company #2025ISMPMI with @nicolasfreiditfrey.bsky.social @asosalop.bsky.social @yijiaaaaaa.bsky.social @mungfoo.bsky.social @hynmn-jeong.bsky.social 😊

All set up for the poster session tomorrow #2025ISMPMI Please join if you wanna know more about transcription factor complexes that play roles during AMS in #MyMarchantia P-407

And, also see posters P-089 @baptistebio.bsky.social and P-182 @madeleinebaker.bsky.social

When your #MyMarchantia lines expressing an SRDX repressor domain fused to a transcription factor show a devo phenotype 🤩 ...so cute!!