Carl Mesarich

🌱 Join us tomorrow for the seminar by Carl Mesarich (@carlmesarich.bsky.social) from Massey University at 11:00h!

👀 Don't miss it!
📍 CRAG Auditorium

👉 https://f.mtr.cool/ynnykimnmh

#AppleScab

#JJC2026 @baudinmael.bsky.social (@irhs-angers.bsky.social) on ancient MAX #effector variants of a #fungal #pathogen evading apoplastic #immunity in #apple

Individually redundant effectors are collectively required for bacterial pathogen virulence Abstract. Host specificity of a plant pathogen is defined by its effector complement. However, it remains unclear whether the full complement is required f

Delighted to see this published in ISMEJ at the end of 2025!! Building on our previous work with the Psa-kiwifruit pathosystem, we competed Psa effector knockout strains against one another, across hosts, to more sensitively identify effector requirements. 🥝🌿
academic.oup.com/ismej/articl...

Ancient MAX Effector Variants of a Fungal Pathogen Evade Apoplastic Immunity in Apple Venturia inaequalis is an Ascomycota fungus responsible for apple scab, the main disease in apple orchards. During infection, the pathogen colonizes the subcuticular space and secretes hundreds of eff...

🧬 New preprint on fungal effector 🍄🍎

We identify AvrRvi6, the first AVR from Venturia inaequalis.

AvrRvi6 is a MAX effector with apoplastic activity, expanding the functional landscape of this major effector family.

📄 bioRxiv: www.biorxiv.org/content/10.6...

26 years after I planted a #kauri sapling on #Waiheke Island 😍

Ancient MAX Effector Variants of a Fungal Pathogen Evade Apoplastic Immunity in Apple https://www.biorxiv.org/content/10.64898/2025.12.25.695362v1

Ancient MAX Effector Variants of a Fungal Pathogen Evade Apoplastic Immunity in Apple https://www.biorxiv.org/content/10.64898/2025.12.25.695362v1

From Nicotiana to apple: effector screening reveals new avenues for durable scab resistance https://www.biorxiv.org/content/10.64898/2025.12.25.696553v1

From Nicotiana to apple: effector screening reveals new avenues for durable scab resistance https://www.biorxiv.org/content/10.64898/2025.12.25.696553v1

Very happy to see this nice piece of work online, led by superstar postdoc Mariana Tarallo. A great collaboration between the teams at @bioprotection.bsky.social/Massey University and the James Hutton Institute!

Now published in Plant Pathology.
'Molecular Investigation of Rlm3 From Rapeseed as a Potential Broad‐Spectrum Resistance Gene Against Fungal Pathogens Producing Structurally Conserved Effectors' - Talbi - Plant Pathology - Wiley Online Library bsppjournals.onlinelibrary.wiley.com/doi/10.1111/...

The first article of Camille Rabeau (CIFRE PhD student @inrae-bioger.bsky.social and @innolea) now on bioRxiv. Camille characterized Leptosphaeria maculans effector genes expressed during stem colonization of rapeseed and identified new resistance sources. www.biorxiv.org/content/10.1...

A 29% cut to the Marsden Fund, plus major cuts to Endeavour, HRC and elsewhere 😠
With success rates already in single figures in some areas and funding not keeping pace with rising costs, this is devastating for New Zealand science

🧪⚔️ When a fungal effector tries to coexist with plant apoplastic bacteria

My poster’s not up until Thursday, but you can already check it out on Zenodo 👀
📎 zenodo.org/records/1585...

🧾 Poster P-166, Thur 17th, 1:30 pm
#2025ISMPMI

New research led by Christiaan Schol showing that the Ecp5 effector of Fulvia fulva is Avr6! Congrats to all co-authors! 🍅

New Paper out!

apsjournals.apsnet.org/doi/epdf/10....

We wanted to know how much genetic variation exists for Zymoseptoria in a single wheat field.

Happy to welcome Keith Thorburn and Ashleigh Mosen to our Bioprotection Aotearoa team at Massey Uni!

Both will be working on PhD projects related to the identification & functional characterization of avirulence effectors in the #AppleScab fungus, Venturia inaequalis 🍏🍎

Structure‐guided insights into the biology of fungal effectors Phytopathogenic fungi cause enormous yield losses in many crops, threatening both agricultural production and global food security. To infect plants, they secrete effectors targeting various cellular...

Structure-guided insights into the biology of fungal effectors

nph.onlinelibrary.wiley.com/doi/full/10....

Use their names: there are no basal, lower, or early diverging fungi Fungal biologists have embraced phylogenies for understanding the biology of this diverse group in an evolutionary framework. In an attempt to highlight lineages of fungi that are distinct from the...

www.tandfonline.com/doi/full/10....

promotional figure

Out in @elife.bsky.social ! 🎉
Thank you @sohambio.bsky.social for your persistence! Also to @asimjaved.bsky.social & @jiaxuwu.bsky.social for your contributions! So excited to keep understanding gall-forming pathogens using these results as a starting point!
elifesciences.org/reviewed-pre...

Great new study from our lab revealing insights in Xanthomonas evolution and how loss of the Crispr genome defense was a key step for X. campestris pv campestris.

Evolution of a vascular plant pathogen is associated with the loss of CRISPR-Cas and an increase in genome plasticity and virulence genes Paauw et al. report on the evolution of a plant pathogenic Xanthomonas pathovar and show that the gain of mobile genetic elements and virulence factors coincided with the loss of the CRISPR-Cas genome...

www.cell.com/current-biol...

Molecular investigation of Rlm3 from rapeseed as a broad-spectrum resistance gene against fungal pathogens producing structurally conserved effectors Recognition of a pathogen avirulence (AVR) effector protein by its cognate plant resistance (R) protein triggers immune responses that render the plant resistant, representing an efficient disease con...

Could we identify broad-spectrum resistances able to recognize structural families of effectors? During her PhD, Nacera Talbi demonstrated proof of concept with the Rlm3 resistance protein, which can recognize members of the LARS structural family. www.biorxiv.org/content/10.1...

Starship giant transposons dominate plastic genomic regions in a fungal plant pathogen and drive virulence evolution Starships form a recently discovered superfamily of giant transposons in Pezizomycotina fungi, implicated in mediating horizontal transfer of diverse cargo genes between fungal genomes. Their elusive nature has long obscured their significance, and their impact on genome evolution remains poorly understood. Here, we reveal a surprising abundance and diversity of Starships in the phytopathogenic fungus Verticillium dahliae. Remarkably, Starships dominate the plastic genomic compartments involved in host colonization, are enriched in virulence-associated genes, and exhibit genetic and epigenetic characteristics associated with adaptive genome evolution. We further uncover extensive horizontal transfer of Starships between Verticillium species and, strikingly, from distantly related Fusarium fungi. Finally, we demonstrate how Starship activity facilitated the de novo formation of a novel virulence gene. Our findings illuminate the profound influence of Starship dynamics on fungal genome evolution and the development of virulence. ### Competing Interest Statement The authors have declared no competing interest.

📣New year, new preprint @biorxiv-microbiol.bsky.social 🎉! A study led by the brilliant @yukiyosato.bsky.social showing that Starship giant transposons dominate plastic genomic regions in the fungal plant pathogen Verticillium dahliae and drive virulence evolution. 🧵[1/12] doi.org/10.1101/2025...

Fascinating insights into #Fusarium oxysporum! 🌟 A new study uses reference-free pangenome variation to reveal the #evolution of accessory chromosomes, showcasing their role in host specificity and horizontal transfer. Wow!!!
#FungalGenomics @mfseidl.bsky.social

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

The Hansen's baccata #2 gene Rvi12_Cd5 confers scab resistance to the susceptible apple cultivar “Gala Galaxy” A new apple scab resistance gene was characterized. It may be a valuable resource for both breeders and scientists, to produce new apple cultivars that are naturally resistant to this dangerous patho...

Looks like Rvi12, the third major apple scab resistance gene to be cloned, encodes an RLK: onlinelibrary.wiley.com/doi/10.1111/...

It’s a dark day for research in Aotearoa New Zealand and the ramifications for the country are huge. Minister Judith Collins has just announced our blue-skies funder will no longer fund humanities & social science research and that 50% of what is funded must have economic benefit.

Congrats, Benjamin - well deserved!

https://www.environmental-genomics.de/liz-flores.html

Let me introduce myself! 😊