Clémence Marchal

Comment la mutagenèse aléatoire induite a changé la donne au 20e siècle Article issu du #QuizAmeliorationDesPlantes n°12 Première Publication 30 mai 2020 La mutagenèse aléatoire induite a profondément et durablement impacté les programmes de sélection depuis les années…

Un peu de lecture à partager un max parce que le traitement de l’actualité c’est toujours pas ça

Les NGT font partie d’un continuum qui a commencé avec la mutagenèse aléatoire induite (mais avec une précision inédite)

creationvarietale.wordpress.com/2024/12/04/c...

New genomic techniques: Council and Parliament strike deal to boost the competitiveness and sustainability of our food systems Council and Parliament reach provisional deal on a set of rules for new genomic techniques, aiming to improve the competitiveness of European agriculture and support the sustainability of our food sys...

European Council and Parliament agree on relaxing rules for bringing genome-edited plants to the market - a central step for facilitating a science-based management of our current plant systems.
www.consilium.europa.eu/en/press/pre...

On the diversity of resting states of NLR immune receptors New story on the rice Pik NLR immune receptor pair — turns out it sits as a 1 MDa membrane-bound beast before activation 🤯. Another wild…

I just published: On the diversity of resting states of NLR immune receptors

New story on rice Pik NLR immune receptor pair — turns out it sits as a 1 MDa membrane-bound beast before activation 🤯. Another wild twist in the ever-expanding universe of NLR resting states!

medium.com/p/on-the-div...

EU einigt sich auf Lockerungen für gentechnisch veränderte Lebensmittel Für viele gentechnisch veränderte Lebensmittel soll es künftig keine Hinweispflicht mehr in Supermärkten geben. Darauf einigten sich Vertreter aus dem Europaparlament und dem Rat der EU-Länder.

Finally! The European Union allows the use of genome editing! 🌱🌾🫛🇪🇺🧬

www.tagesschau.de/wirtschaft/v...

The Pik NLR pair accumulates at the plasma membrane as a hetero-oligomeric sensor-helper immune protein complex prior to activation https://www.biorxiv.org/content/10.64898/2025.11.30.691369v1

Thanks Matteo!

Helixer: ab initio prediction of primary eukaryotic gene models combining deep learning and a hidden Markov model - Nature Methods By leveraging both deep learning and hidden Markov models, Helixer achieves broad taxonomic coverage for ab initio gene annotation of eukaryotic genomes from fungi, plants, vertebrates and invertebrat...

Helixer: a tool for ab initio gene annotation with broad taxonomic coverage. @usadellab.bsky.social @apmweber.bsky.social @weberlab.bsky.social

www.nature.com/articles/s41...

We are looking for a Head of Cell Biology here at @kwsgroup.bsky.social Vegetables.

This is a permanent, full-time position located in Wageningen, Netherlands.

jobs.kws.com/job/Wagening...

#PlantScience #PlantSciJobs #PlantScienceJobs #PlantCellBiology #PlantBreeding #PlantSciJob #PlantScienceJob

Check out our new story on the famous rice Pik NLR pair, led by @clemmar.bsky.social and @hsuanpai.bsky.social! Turns out they form a massive 1 MDa membrane-associated complex before activation 🤯
A cool new example of the diversity of NLR resting states!

Thanks Nick!

Development's Pathway to Independence Programme Our grants support and encourage the sharing of knowledge throughout the community by facilitating international collaboration, event attendance and the organisation of scientific meetings, conference...

Applications are open for @dev-journal.bsky.social 2026 Pathway to Independence (PI) programme, supporting postdocs applying for group leader positions:

Mentoring
Profile raising
Leadership training
Network building

Spread the word...

www.biologists.com/grants/devel...

16/n. Thank you to my wonderful colleagues for making this happen!

15/n. Our findings contribute to the growing evidence that resting state configurations vary across NLRs. This knowledge could be leveraged for disease resistance engineering strategies complementary to approaches focussing solely on effector binding (this is what I will explore in my ERC project!)

14/n. Caveat: Given that the ~1 MDa bands were identical regardless of the presence of GFP, we could not conclude that the Pik pair was activated by GFP or whether Pikm-2(EE) is a non-functional mutant of Pikm-2 that is blocked in a conformation similar to that of its resting state.

13/n. We detected GFP at ~1 MDa only when GFP was co-expressed with Pikm-1(Enhancer) and Pikm-2(EE), suggesting that the Pik-1 ligand is integrated into the Pik hetero-complex

12/n. What about the ligand? You may ask. We introduced mutations in the MADA motif present in the N-terminal α1 helix of Pik-2 (Pik-2EE) to abolish cell-death induction in presence of Pik-1 and its ligand to facilitate biochemical assays and address this question.

11/n. We confirmed that the hetero-complex accumulates at the plasma membrane with confocal microscopy.

10/n. Where is the Pik complex located? We show that in absence of their paired partner, Pik-1 mostly accumulates in the soluble fraction, while Pik-2 is present in both soluble and membrane fractions. Upon co-expression with Pik-2, Pik-1 shifts from the soluble to the membrane fraction.

Paired plant immune CHS3-CSA1 receptor alleles form distinct hetero-oligomeric complexes Pairs of intracellular immune receptors heterodimerize and oligomerize to activate immunity in plants.

9/n. The Pik pair forms a hetero-complex in its resting state, similar to what was observed for TIR-NLR sensor pairs CSA1-CHS3 and RPS4-RRS1. doi.org/10.1126/scie... , doi.org/10.1101/2025...

8/n. We generated a “heavy” variant of Pik-1 C-terminally tagged with mCherry and v5 (Pik-1 “heavy”) to help us detangle this! The idea was that if Pik-1 and Pik-2 formed a heterocomplex, we would see a size shift when co-expressing Pik-1 “Heavy” with Pik-2 and probing for Pik-2. And we did!

a black and white photo of a young boy sitting at a desk with his hand on his chin and the words `` hmmmm '' . ALT: a black and white photo of a young boy sitting at a desk with his hand on his chin and the words `` hmmmm '' .

7/n. However, given that Pik-1 and Pik-2 are very similar in size, it was impossible to determine whether we were observing a Pik-1 oligomer and Pik-2 oligomer with similar stoichiometries, or a Pik-1/Pik-2 heterocomplex.

6/n. We performed non-denaturing BN-PAGE to investigate the oligomerisation state of Pik-1 and Pik-2 in the resting state and show that both NLRs form a massive ~1 MDa complex when co-expressed. It took @hsuanpai.bsky.social and I some time to identify to right extraction conditions this complex!

5/n. Previous work from the Banfield lab showed that Pik-1 and Pik-2 associate both prior to and upon effector binding, prompting us to ask whether Pik-1 and Pik-2 form dimers or oligomers in their resting state.
journals.plos.org/plosone/arti...

4/n.Here, we investigated the oligomeric state of the sensor Pik-1 and helper Pik-2 NLR pair in the resting state.We used both wild-type Pik-1 that recognises effectors from M. oryzae via its HMA domain and engineered Pik-1(Enhancer) that recognises GFP via a nanobody www.science.org/doi/10.1126/...

3/n. Although many NLRs are known to oligomerise upon the perception of effectors, much less is understood about their resting state prior to pathogen recognition. Here is what we know for some CC-type NLRs:

2/n. NLRs can play specialised roles in either detecting effectors (sensor NLRs) or triggering the immune response (helper NLRs) and might function together as pairs or within larger networks.

Cartoon depicting pathogens secreting molecules in the apoplast and inside the plant cell, which can be recognised by plant immune receptors located at the plasma membrane or in the cytosol

1/n. Nucleotide-binding and leucine-rich repeat receptors (NLRs) are key players in plant immune systems that recognise and respond to harmful pathogen effector proteins.

CC-NLRs exhibit diverse conformations in the resting state. Figure depicts different NLR resting and activated states. While ZAR1 exists as a monomer bound to its guardees in its resting state, several forms have been observed for the NRC2 helper, including dimers, tetramers, and filaments. While filament-like structures were observed via confocal microscopy for NRC2 upon overexpression in planta, these structures were not detected for its paralog NRC4, suggesting a potentially different resting state configuration for NRC4. Our work suggests that the Pik CC-NLR pair forms a hetero-complex bound to the plasma membrane in its resting state. How effector binding to the integrated domain (ID) of the Pik-1 sensor leads to the activation of the complex remains to be determined.

Excited to share our latest work on plant immune receptor biochemistry! @kamounlab.bsky.social @hsuanpai.bsky.social @mpcontreras.bsky.social Jose Salguero Linares @danielluedke.bsky.social @adnroide.bsky.social @jiorgoskourelis.bsky.social

www.biorxiv.org/content/10.6...

AGO5 restricts virus vertical transmission in plant gametophytes The propagation of a viral infection from a host parent to its progeny is known as vertical transmission, or seed transmission in plants. It allows viral infections to rapidly spread locally via polle...

Preprint alert! It is my great pleasure to announce the first manuscript from the lab, a story that started @gmivienna.bsky.social and was mainly accomplished by the intrepid @gesahoffmann.bsky.social at @mpi-mp-potsdam.bsky.social. A brief thread with our findings
www.biorxiv.org/content/10.1...

Glad to have this finally published: www.sciencedirect.com/science/arti... lots of new data since the #preprint. If you are into selective #autophagy, #evolution, #proteostasis Please have a look!