Alex Guyon
@alexguyon.bsky.social
190 followers 460 following 14 posts
PhD student in the Schornack Group @slcuplants.bsky.social. Interested in plant-microbe interfaces. https://www.slcu.cam.ac.uk/people/alex-guyon
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alexguyon.bsky.social
Thanks very much, only possible thanks to your biosensors!
alexguyon.bsky.social
That's a cool parallel, I guess the cell biology of the pollen vegetative cell containing the sperm cells is analogous to a root cortex cell containing an arbuscule. Did you see the PI(4,5)P2 biosensor localising to subdomains of the peri-germ cell membrane, similar to the arbuscule tips?
alexguyon.bsky.social
8/ TL;DR:
✅ Phosphoinositide signatures at plant-microbe interfaces are dynamic
✅ Mutualist colonisation reshapes pathogen interface identity
✅ This shift correlates with enhanced resistance, suggesting membrane identity may influence infection outcome.
alexguyon.bsky.social
8/ Beyond just documenting these dynamics, our work asks:
🌱 Can we rethink host-pathogen “specialised” membranes as dynamic, context-dependent landscapes?
🔬 Are immune evasion strategies vulnerable in complex microbial environments?
alexguyon.bsky.social
7/ So what's going on? We propose that PI4P exclusion from haustoria is a pathogen-driven strategy, likely involving secreted effectors.
But during AM symbiosis, trafficking to arbuscules may override this, forcing the pathogen into an interface it didn’t design.
alexguyon.bsky.social
6/ Even more: co-colonisation enhances resistance to P. palmivora. Mutualist presence seems to rewire the pathogen interface.
alexguyon.bsky.social
5/ But here's the twist, during co-colonisation, haustoria begin recruiting PI4P
That’s a fundamental shift in membrane identity. And yes - we observed single plant cells simultaneously harbouring both an arbuscule and a haustorium!
alexguyon.bsky.social
4/Watch it in action! Here’s PI(4,5)P₂ (via biosensor P24Y) tracking fungal growth during AM symbiosis. Captured using @jenmcgaley.bsky.social‘s AMSlide.
alexguyon.bsky.social
3/ In single infections:
• PI(4,5)P₂ is tip-enriched in arbuscules but uniform around haustoria. Each interaction has a distinct membrane fingerprint.
• PI4P is present at the periarbuscular membrane of the mutualist but absent from haustoria of the pathogen.
alexguyon.bsky.social
2/ Phosphoinositides (PIPs) are key lipids that define membrane identity. We visualised PI(4,5)P₂ and PI4P biosensors from @yvonjaillais.bsky.social in Nicotiana benthamiana during root colonisation by a mutualist AM fungus - F. mosseae and a pathogen - P. palmivora. www.biorxiv.org/content/10.1...
alexguyon.bsky.social
1/🚨 New preprint alert! Can mutualists and pathogens co-colonise the same living plant cell and what does that do to the plant membranes that surround these microbes?
Reposted by Alex Guyon
dariuskos.bsky.social
Excitingly, we also made it on the cover of the current issue of @theplantjournal.bsky.social with some of my #microscopy images checking for #immunofluorescence signal of FLAG-tagged cytochrome c6A in #chlamydomonas!
Reposted by Alex Guyon
dromius.bsky.social
Intracellular pathogens can form extensive hyphal structures. Here, the pathogen Phytophthora palmivora (magenta) produces invasive hyphae in a living epidermal cell of a Nicotiana root. The plant surrounds the invader by an 'extra-invasive hyphal membrane' (yellow)📸 @alexguyon.bsky.social
Reposted by Alex Guyon
dromius.bsky.social
Preprint! w/ C. Strullu-Derrien,R.Wightman,L.P.McDonnell, G.Evans,F.Fercoq,P.Kenrick & A.Ferrari

An ancient plant symbiotic fungus with distinct features identified through advanced fluorescence & Raman imaging

@slcuplants.bsky.social @nhm-london.bsky.social Cambridge Graphene Centre @mnhn.fr
Reposted by Alex Guyon
slcuplants.bsky.social
We are thrilled to have been awarded a silver-gilt medal at our first Chelsea Flower Show! 🪻

An enormous thank you to everyone who contributed to this success - @eng.cam.ac.uk, Darwin Nurseries and Oakington Garden Centre!

#RHSChelsea @cambridgeuni.bsky.social
alexguyon.bsky.social
Great to see this out in the wild now!
dromius.bsky.social
Read & RP. New preprint by Alex Gavrin from his time in our team - Inactivation of Medicago Glucan binding protein 1 (GBP1) offers: An approach to enhance symbiotic nitrogen fixation.
www.biorxiv.org/content/10.1...
alexguyon.bsky.social
Hi all, finally got around to making a Bluesky account. Looking forward to seeing all the cool work here and sharing some of my own!
Reposted by Alex Guyon
seedrevolutionlab.bsky.social
Great start to the final day of #ICIPS2025 with a talk by @dromius.bsky.social showcasing the work of @davidjhoey.bsky.social about genetic control of marchantia reproductive strategies