Varsha Mathur
@varshamathur.bsky.social
Evolutionary biologist | MSCA Postdoctoral Fellow @univienna | Previously EMBO Postdoctoral Fellow, JRF Brasenose College, Oxford Biology | protists/parasites/organelles 🔬🧬
Integration and regulation of stolen organelles in a marine protist academic.oup.com/ismej/advanc... #jcampubs
Integration and regulation of stolen organelles in a marine protist
Abstract. Chloroplast-stealing (a.k.a., “kleptoplastidic”) plankton transiently obtain and integrate prey metabolic machinery into their own cells. To do s
academic.oup.com
What's predation like in the microbial world? Greg Velicer @usyseth.bsky.social and I take you on a tour in our new review! @ethz.ch @cnrs.fr
Nature Reviews Microbiology@natrevmicro.nature.com · 3mo agoNew online! Predation in microbial communities: gradients of nutritive killing
Sailing in @biorxivpreprint.bsky.social ready for summer, our study on the iconic Portuguese man o' war 🪼 is out: www.biorxiv.org/content/10.6.... We use (epi)genomics to understand a critter that fascinates me since childhood. Massive team effort with @obog.bsky.social, Cummins and Neely groups. 🧵
Very happy something like this is now available. In protist diversity research we use the rDNA extensively, but I for one doesn't know enough about it's structure, variation, and implications www.annualreviews.org/content/jour...
Organization of Ribosomal RNA Genes in Eukaryotes
In eukaryotes, ribosomal RNA genes (rDNA) encode the major ribosomal RNA molecules and are typically organized into a distinctive genomic structure involving tandem repetition of a polycistronic codin...
annualreviews.org
Check the brilliant work by Sanjay Narayanaswamy in Nature Comm. www.nature.com/articles/s41.... He established a scalable Gastruloid protocol and showed that in gastruloids of Nematostella axial polarity and germ layer restoration and sorting depends on a Notch-Wnt signaling feedback loop.
Notch coordinates self-organization of germ layers and axial polarity in sea anemone gastruloids - Nature Communications
Here they show that gastruloids made of embryonic cells of the sea anemone Nematostella can robustly regenerate whole organisms. They show that Notch signaling is crucial to sort out the randomly disp...
nature.com
Do #tintinnids dream of electric sheep? 🤯 Here is a single cell capable of building a lorica and living inside it for protection... it also swims, feeds, hunts Can even detect and habituate to mechanical cues! #celllearning #protistsonsky #cilia Read more in our preprint doi.org/10.64898/202...
Out Now! Molecular and cellular insights into the parasitic infection of bloom-forming marine diatoms by Pirsonia diadema #MicroSky
Molecular and cellular insights into the parasitic infection of bloom-forming marine diatoms by Pirsonia diadema
Nature Microbiology, Published online: 21 July 2026; doi:10.1038/s41564-026-02421-4Ultrastructure expansion microscopy, live-cell imaging and time-resolved dual RNA sequencing reveal the infection dynamics of a microparasite, providing insights into how Pirsonia diadema shapes marine trophic networks.
go.nature.com
So happy to share our new paper out now in @natmicrobiol.nature.com! We establish Pirsonia-Coscinodiscus as a model pathosystem and uncover how this tiny parasite infects and kills bloom-forming marine diatoms 🌊🦠 rdcu.be/fuQyF
We are recruiting a postdoc to explore how corals evolved coloniality, novel cell types, and photosymbiosis using single-cell and genomic approaches. Based at Academia Sinica, Taipei. More: sgel.biodiv.tw
The third chapter in our coral single-cell trilogy is here. After mapping cell type diversity in Stylophora (Levy 2021) and exploring facultative symbiosis in Oculina (Levy 2025), we now uncover cell type-specific responses to heat stress. Find out more in @xgrau.bsky.social's thread below.
Cell-resolved transcriptional responses during heat-induced coral bleaching and recovery
Coral reefs depend on an intracellular symbiosis between cnidarian hosts and photosynthetic dinoflagellates that is disrupted by ocean warming, causing coral bleaching. Yet how these responses are dis...
biorxiv.org
Xavier Grau-Bové 🌾@xgrau.bsky.social · 2w agoI'm happy to share our latest on #coral single-cell biology: a transcriptomic timecourse of heat stress in Stylophora pistillata, from bleaching to recovery 🪸🌊 This project was spearheaded by Shani Levy and carried through in @arnausebe.bsky.social's lab at @crg.eu. www.biorxiv.org/content/10.6...
Apparently the "boring billion" was actually exciting! We provide molecular evidence of complex Mesoproterozoic eukaryotic communities. So happy to see this out 🥳 Thanks to @phoebefossil.bsky.social , Hélène Morlon & @fburki.bsky.social for a lovely collab! doi.org/10.1073/pnas...
Plastid endosymbiosis without gene transfer - dinoflagellates can do it #ProtistsOnSky #Kareniaceae #plastids
Recent plastid replacement in Karlodinium ballantinum (Kareniaceae, Dinoflagellata) challenges the paradigms of endosymbiotic gene transfer
Abstract. Plastids, the photosynthetic organelles of eukaryotes, arose via endosymbiosis of cyanobacteria by a eukaryotic host and were subsequently spread
academic.oup.com
Most people have never heard of #apusomonads. Yet these tiny protists occupy an important position in the eukaryotic tree of life. And we know so little about them! We're looking for a Master's student to help uncover their hidden diversity. #ProtistsOnSky 🧵 @ibe-barcelona.bsky.social @prbb.org
Cool video about the nitroplast that’s also a testament to why basic science is important! youtu.be/g9B3gBhcwqM?...
This cell just changed biology
YouTube video by Grist
youtu.be
What happens to labile carbon when it reaches the Arctic seafloor? In our new paper led by Juan Carlos Trejos-Espeleta, we show how marine fungi efficiently assimilate DOC & promote C retention in Arctic fjord sediments Nice 🧵 from @ggomezsaez.bsky.social 👇 journals.plos.org/plosbiology/...
Fungi enhance microbial carbon retention in high Arctic fjord sediment
Fungi act as critical biological carbon storage reservoirs in soil ecosystems, but what about marine sediments? This study shows that marine fungi promote carbon storage in arctic fjord sediment, hot-...
journals.plos.org
Gonzalo Gomez Saez@ggomezsaez.bsky.social · 2mo agoArctic fjords are hotspots for carbon sequestration affected by global warming. In our last article, published in #PLoSBiology, we show that fungi living in Svalbard sediments efficiently assimilate labile DOM and retain it as microbial biomass, rather than allowing it to be rapidly respired.
🎉 Excited to share that Elisabeth Hehenberger and I have been awarded a 🇵🇱🇨🇿 NCN–GAČR grant! We'll explore the diversity, ecology, and interactions of Perkinsea, a fascinating and largely overlooked group of parasitic #protists in #freshwaters. Looking forward to this exciting collaboration!
Viruses play a major role in the functioning of ecosystems. They profoundly influence the dynamics of microbial communities, the flow of matter & global biogeochemical cycles. phys.org/news/2026-06... via @sciencex.bsky.social #virology #genomics #ecology #science #SciChat
The giant viruses that orchestrate life in the polar regions
Viruses play a major role in the functioning of ecosystems. They profoundly influence the dynamics of microbial communities, the flow of matter and global biogeochemical cycles. Yet despite their abun...
phys.org
How did octopuses evolve novel traits? Rishav Mitra, Richard Han, Trey Scott, et al serendipitously discover a unique ribosome adaptation that increases the accuracy of protein synthesis and evolved alongside their elaborate nervous systems vs deep sea relatives. www.biorxiv.org/content/10.6...
Not everyday a friend is able to define a new organelle!!! If you like membrane compartimentalization and are interested in how cells responde to stress in membrane tension, check this out!👇👇 Congrats to Elda and co!! www.biorxiv.org/content/10.6...
In September we will have the pleasure of hosting Karla and @fmikus.bsky.social from the labs of @dudinlab.bsky.social and @gautamdey.bsky.social. If you are around Granada please join us for their talk! They will present ExÂME, an incredible initiative to build a 3D atlas of protists diversity!
Facultad de Ciencias@fcienciasugr.bsky.social · 4w ago🔬 Seminario: Microscopía de expansión: una nueva perspectiva sobre la diversidad de la vida 🗓️ 8 de sep ⏰ 11:00 am. 📍 Salón de Grados @fcienciasugr.bsky.social 🗣️ Dra. Karla Azucena Juárez y Dr. Félix Mikus 🔗 fciencias.ugr.es/facultad/not...
Our News & Views article “Body-plan organizer in comb jellies hints at animal ancestry” now published in @nature.com 🎉 We discuss fascinating work revealing organizer activity in comb jellies & the evolution of animal development. rdcu.be/fsLWq @ruthstyfhals.bsky.social @msarscentre.bsky.social
#Archaea Gene duplications, rather than horizontal gene transfers from bacteria, seem to be the primary drivers behind the increased genome sizes in Asgard archaea #evolution #microbes @tonigabaldon.bsky.social @microbiobits.bsky.social
Phylogenomics of Asgard archaea reveals a unique blend of prokaryotic-like horizontal transfer and eukaryotic-like gene duplication - Nature Communications
The genomes of Asgard archaea, the closest prokaryotic relatives to eukaryotes, are larger than those of other archaea and contain multiple genes seemingly acquired from bacteria. Here, Manzano-Morales and Gabaldón quantify gene duplication, loss, and transfer events in Asgard genomes, showing that gene duplications, rather than horizontal gene transfers, are the primary drivers behind the increased genome sizes.
dlvr.it
New preprint: We studied the population dynamics of Arctic #phytoplankton and #mycoplankton and found evidence for chytrid-mediated diatom bloom termination. www.biorxiv.org/content/10.6... Congrats @paulinethome.bsky.social #protists #protistsonsky #algae #diatoms #chytrids
It is always alarming to read about the effects of marine heatwaves 💔 In 2025, toxin-producing dinoflagellate blooms caused mass mortality across marine organisms, linked to a new Karenia species, K. cristata (not even known to bloom in Australia before!) rdcu.be/fsKE4
A catastrophic marine mortality event caused by a complex algal bloom including the brevetoxin producer Karenia cristata
Nature Ecology & Evolution - Genomic characterization and toxicity assays identify Karenia cristata as a brevetoxin-producing species that is the dominant component of the prolonged microalgal...
rdcu.be
"I hope that this parasite will ‘stick’ to some of you as well, so that you too can admire the heart-shaped, dividing Giardia trophozoites through your microscopes." 🫶 #protistsonsky rdcu.be/fsBia
Stuck on you Giardia
Nature Microbiology - Staffan Svärd reflects on his 30-year relationship with Giardia, which has stayed on his mind in a manner reminiscent of its adhesive trophozoite form.
rdcu.be
A single-cell atlas of Toxoplasma sexual development in the feline intestinal tract www.nature.com/articles/s41... #protists #singlecell
A single-cell atlas of Toxoplasma sexual development in the feline intestinal tract - Nature Microbiology
Single-cell RNA sequencing is used to study the sexual development of Toxoplasma gondii in cats, generating a transcriptional atlas and showing that the female-specific gene AP2X6 functions as a…
nature.com
Discovery of an adhesion GPCR regulating mating in choanoflagellates, by Alain Garcia de las Bayonas & Nicole King. Absolutely stunning work - choano cell biology is going next level www.biorxiv.org/content/10.6...
Our group is moving from @mpi-bio-fml.bsky.social to the maritime city of Kiel! ⛵️🩵 I will lead the Department of Marine Plant Development and Physiology @uni-kiel.de 🌱🪸🌊 Look out for opportunities to join us in this exciting & growing hub for Plant, Marine & Evolutionary Biology in North Germany 🇩🇪
