Very cool work that sounds very familiar! Maybe we chose to work in the wrong species... 🌱

www.science.org/doi/10.1126/...

New Article: "Occupancy-based mechanism is the chief mode of ROS1 function in preventing DNA hypermethylation" rdcu.be/fb7P0

ROS1 mediates DNA demethylation via a passive mechanism; ROS1 occupancy marks & regulates accessible chromatin, highlighting its diverse roles.

Spatial organization of plant defense at the infection front www.biorxiv.org/content/10.64898/2026.04...

Two papers on targeted DNA methylation editing for Arabidopsis came out within a week from each other.

1. www.nature.com/articles/s41...
2. academic.oup.com/pcp/advance-...

#PlantSciences

Details of the three PhD projects on offer: Primed for Protection: Cell Wall Modifications in Plant Defense and Long-Term Immunity, Engineering Stomata: How Shape Informs Function: and Signalling Complexes and Cell Wall Changes during Plant Reproduction

Interested in plant development and/or cell walls? We (Sam Amsbury, Andrew Fleming and I) have three PhD positions at the University of Sheffield open for applications until 7th January. We offer a friendly, jointly-run lab, great facilities, an affordable city and proximity to the Peak District!

🌿 3 new PhD positions in the Ton lab @PPS_UoS. Part of the ERC project '#PlantMemo', exploring how plants remember & respond to stress.
🧬 PhD 1 (UK only)👉 www.findaphd.com/phds/project...
🦠 PhD 2 (UK & EU)👉 www.findaphd.com/phds/project...
🌱 PhD 3 (UK only)👉 www.findaphd.com/phds/project...
#PhD

Genome-wide selection on transposable elements in maize While most evolutionary research has focused on single nucleotide polymorphisms (SNPs), transposable elements (TEs) represent a major but understudied source of mutations that can influence organismal...

Really nice study on the evolutionary dynamics of TEs in maize by @jrossibarra.bsky.social and colleagues 👇
www.biorxiv.org/content/10.1...

SALICYLIC ACID SENSOR1 reveals the propagation of an SA hormone surge during plant pathogen advance Salicylic acid (SA) is a key phytohormone that orchestrates immune responses against pathogens, including Pseudomonas syringae bacteria. The timing and extent of SA accumulation are tightly controlled...

FRET sensor for SA developed. www.science.org/doi/10.1126/...

Transposable elements are vectors of recurrent transgenerational epigenetic inheritance DNA methylation loss at transposable elements (TEs) can affect neighboring genes and be epigenetically inherited in plants, yet the determinants and significance of this additional system of inheritan...

Happy to share the results of a long-haul post-doc project, now online @science.org, aiming at understanding the rules of transgeneration epigenetic inheritance over TEs in plants and its extent and impact in nature. More below!
doi.org/10.1126/scie...

Gene body methylation regulates gene expression and mediates phenotypic diversity in natural Arabidopsis populations - Nature Plants This study shows that epigenetic gene body DNA methylation regulates transcription and accounts for much of its variance in the Arabidopsis population, efficiently identifies genes regulating diverse ...

Interesting!

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

#plantscience #epigenetics

forgot to include #plantscience #plantimmunity #epigenetics !

It's been a massive effort with help from so many people. Thank you @jurriaanton.bsky.social, @plantylisasmith.bsky.social, and all other co-authors not on Bluesky. Thank you @psaima.bsky.social and @dcb40.bsky.social for some very useful conversations during my viva! 9/9

This work sheds new light on ROS1 (the best plant protein?), uncovering new and exciting genomic targets. Beyond Arabidopsis, we’re also excited by the translational potential of this system, providing a new way to introduce epigenetic variation into other plant species 🌱✨
8/9

We needed to block the hypermethylation building up in peri/centromeres. Our genetic attempts hit roadblocks, so we switched to a pharmacological approach: 5-Aza, a DNA methylase inhibitor.
Remarkably, 5-Aza not only boosted ROS1-induced resistance to Pst-Lux, it prolonged the immune memory!
7/9

This got us thinking….

Hypomethylation in (peri)centromeres is associated with resistance to the same pathogens that ROS1 immune memory resists (Furci et al 2019; Cambiagno et al 2018). So, could this re-methylation response in the (peri)centromeres be negatively regulating immune memory?
6/9

ROS1 caused widespread demethylation and small RNA loss in chromosome arms, *but* in the highly repetitive pericentromeric/centromeric regions we saw the opposite — increases in DNA methylation and small RNAs.
5/9

The obvious question: how? To tackle this, we did small RNA sequencing, DNA methylation sequencing (short-read and long-read), and RNA sequencing. What we saw was surprising….
4/9

Bursts of ROS1 activity robustly induced resistance against the pathogenic bacteria Pst-Lux and the oomycete pathogen Hpa.

This immune memory, generated by ROS1, lasted 1-2 weeks, providing an ideal system to study both the establishment and erasure of immune memory.

3/9

In Arabidopsis, the removal of an epigenetic mark, DNA methylation, often occurs in response to pathogen infection or abiotic stress.
We used an estradiol-inducible gene construct for the DNA demethylase ROS1 to transiently increase demethylation activity in plants.
2/9

From recall to reset: the role of DNA (de)methylation in modulating plant immune memory Epigenetic reprogramming is increasingly recognised as a driver of plant immune memory, yet its molecular basis remains poorly understood. Using a chemically inducible transgene in Arabidopsis, we tra...

Very excited to finally share the main findings from my PhD, now out as a preprint!

We developed an epigenetic system to understand how plants remember and forget past infections - a phenomenon known as immune memory 🌱🧬🧠

Highlights below! 1/9

www.biorxiv.org/content/10.1...

Somatic mobility of transposons is explosive and shaped by distinct integration biases in Arabidopsis thaliana Background The movement of transposable elements (TEs) in somatic cells generates genetic and phenotypic diversity across the soma of individual organisms. This process is especially important in plan...

www.biorxiv.org/content/10.1...

very cool work!

New research aims to unlock stressful plant memories New research led by Prof Jurriaan Ton aims to uncover how plants adapt and survive in challenging environments with the ultimate goal to create more resilient crops.

Plants remember stress! The PlantMemo project, led by ‪@jurriaanton.bsky.social‬, has secured an ERC Advanced Grant for an exciting project decoding how stress “memories” boost plant resilience—paving the way for hardier crops.
🔗 www.sheffield.ac.uk/biosciences/...

#PlantScience #PlantImmunity #ERC

Herbivory-induced green leaf volatiles increase plant performance through jasmonate-dependent plant–soil feedbacks - Nature Plants This study reports that herbivory-induced volatiles can trigger plant–soil feedbacks that boost performance and yields of cereals in the field.

📜 Herbivory-induced green leaf volatiles increase plant performance through jasmonate-dependent plant–soil feedbacks

🧑‍🔬 Lingfei Hu, Meng Ye, @matthiaserb.bsky.social, Jianming Xu, et al.

📔 @natplants.nature.com

🔗 www.nature.com/articles/s41...

#️⃣ #PlantScience #PlantImmunity #Herbivory

Extensive N4 cytosine methylation is essential for Marchantia sperm function Global N4 cytosine methylation in Marchantia polymorpha sperm regulates gene expression and promotes sperm fertility.

I'm thrilled to share that our study is now published in Cell:
Extensive N4 cytosine methylation is essential for Marchantia sperm function.
www.cell.com/cell/fulltex...
This paper confirms our 4mC discovery in Marchantia sperm and takes it much further.
A thread: 0/13

Misregulation of the jasmonate signaling pathway leads to altered plant microbiota interaction and plant stress responses The model plant Arabidopsis thaliana hosts diverse microbial communities collectively known as the microbiota. The plant microbiota is generally taxonomically structured. Some of the members can promo...

‼️we are pleased to share the first work coming from my lab on biorxiv.

Misregulation of the jasmonate signaling pathway leads to altered plant microbiota interaction and plant stress responses biorxiv.org/content/10.1...

1/n

thanks! will have a look

get the impression continuous light is a bit risky from this. thanks!

does Arabidopsis thaliana cycle through generations faster in 24h light or is 16h optimal? struggling to find any papers on this .. #plantsci

Salt stress activates the CDK8-AHL10-SUVH2/9 module to dynamically regulate salt tolerance in Arabidopsis - Nature Communications The authors demonstrate that salt stress activates CDK8, which phosphorylates AHL10 and promotes its degradation. AHL10 is involved in recruiting SUVH2/9 to repress salt-responsive genes. The CDK8-AHL...

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

#plantscience

CRISPR targeting of H3K4me3 activates gene expression and unlocks centromeric crossover recombination in Arabidopsis H3K4me3 is a fundamental and highly conserved chromatin mark across eukaryotes, playing a central role in many genome-related processes, including transcription, maintenance of cell identity, DNA dama...

Very excited to share this new preprint from the lab (shorturl.at/l7lNq)! @hendersi.bsky.social si.bsky.social @camplantsci.bsky.social