Cameron Dale MacQuarrie

thestacks.orgMorphological transformation of Chlamydomonas smithii grown in Marine Broth mediumMarine Broth induces extreme morphological transformation in C. smithii: Cells shift from typical ellipsoid shape to amorphous forms with thin wisp-like appendages containing mitochondria, revealing u...

New pub from @ArcadiaScience 🧵 We found that C. smithii — a freshwater green alga — undergoes wild morphological transformations when grown on Marine Broth. Huge cells with mysterious wisp-like appendages. Here's what we saw. thestacks.org/publications... [1/9]

What triggers this? What are the wisps? Is it adaptive or a stress response? We don't know yet. We're sharing these observations now because they're unexpected and we want feedback — similar phenomena in other systems, mechanistic ideas, experimental priorities. [8/9]

All raw microscopy data are on BioImage Archive and image processing tools are on GitHub. If you've seen anything like this in algae or other microbes on rich media, we'd love to hear from you. [9/9]

When we stained with mitochondrial dyes, we detected signal within these appendages — in one case extending nearly 200 µm from the cell body. [6/9]

We also saw reorganization of chloroplasts and mitochondria inside the transformed cells. In some, chloroplasts clustered at the periphery while mitochondria concentrated in a central zone — a striking spatial separation from their normally close association. [7/9]

Erdschreiber's medium has similar salt levels to Marine Broth but lacks organic nutrients like peptone and yeast extract. Cells on Erdschreiber's got bigger and rounder, but didn't develop the extreme amorphous shapes. This suggests it's not just osmotic stress — organic nutrients seem key. [4/9]

Some of the most striking features: thin wisp-like appendages extending from cell bodies. They were barely visible in raw images but popped out after contrast enhancement. They don't beat like flagella and seem mostly static. [5/9]

We'd previously noticed C. smithii could grow on marine media while C. reinhardtii couldn't, and that the cells looked "larger and rounded." But we'd resuspended those cells in water, which could cause osmotic swelling. So we went back and imaged them properly — in the growth medium itself. [2/9]

The results were way more dramatic than expected. After 40+ days on Marine Broth agar, cells were way larger, amorphous, packed with vacuole-like structures, and completely non-motile. Nothing like the tidy ellipsoids you see in standard freshwater media. [3/9]

bit.lyChlamydomonas Cellular Phenotypes Enable in vivo Validation of Computationally Designed Therapeutic ADA1 VariantsPoster presented at CellBio 2025 in Philadelphia, PA. December 2025Abstract:Adenosine deaminase (ADA) deficiency causes severe combined immunodeficiency, and current treatments include enzyme replacem...

6 Dec 2025

Excited to share some new work from @arcadiascience.com at #CellBio2025! We’re using Chlamydomonas reinhardtii as a rapid in vivo platform to model ADA1 deficiency and test computationally designed therapeutic ADA1 variants. Poster PDF: bit.ly/chlamy-ADA

6 Dec 2025

zoogle.arcadiascience.com told us Chlamy is a great model for ADA1 — so we tried it! Come chat about it: Sunday Dec 7, 2:15–3:45 pm (digital poster, near the @ascbiology.bsky.social booth) Monday Dec 8, 2:15–3:45 pm (paper poster, B538)

arcadiascience.comCareers | Arcadia ScienceEvolve with Arcadia.

6 Dec 2025

We're hiring! www.arcadiascience.com/careers

research.arcadiascience.comChlamydomonas cpc1-1 mutant exhibits unexpected growth phenotypesComparative analysis of <i>Chlamydomonas </i>strains revealed that a <i>cpc1-1</i> mutant has three unexpected growth phenotypes across different media types, suggesting possible genetic background co...

Discovered some unexpected growth phenotypes in Chlamydomonas flagellar mutants! The cpc1-1 strain (with central pair complex defects) shows surprising metabolic traits that might be independent of its flagellar defects. 🧵 research.arcadiascience.com/pub/observat... [1/9]

To figure this out, we're testing another CPC1 mutant (cpc1-2) from a different genetic background and trying to rescue both with wild-type CPC1 expression. This should tell us if these growth phenotypes are due to the mutation or genetic background. [8/9]

This work highlights why genetic background matters in model organisms! Even after multiple rounds of backcrossing, unexpected phenotypes can emerge that may not be directly related to the gene you're studying. @ArcadiaScience [9/9]

Third, after 47 days, cpc1-1 was the ONLY strain that could grow on marine medium with high salt content, revealing an unexpected halotolerance. [6/9]

Why does cpc1-1 behave so differently? It might be retaining genetic material from its parent strain despite backcrossing. Or maybe the CPC1 protein itself plays a role in metabolism - it does interact with enolase and other glycolytic enzymes! [7/9]

First, cpc1-1 showed enhanced growth on media with proteose peptone, outperforming wild-type strains that barely grew in this condition! [4/9]

Second, on nitrate-containing media, wild-type C. reinhardtii and ida4 showed chlorosis (yellowing) as expected due to their nit2 mutation. But cpc1-1 maintained dark green colonies, suggesting it can use nitrate efficiently. [5/9]

We were studying flagellar mutants as models for human ciliary diseases when we noticed something odd about their growth patterns. So we decided to compare growth across different media types to see if these mutations affect metabolism beyond just flagellar function. [2/9]

The cpc1-1 mutant (which has defects in the central pair complex of flagella) showed three surprising growth phenotypes that weren't present in other strains, including the ida4 mutant (which has inner dynein arm defects). [3/9]

Cameron Dale MacQuarrie reposted

Arcadia Science

@arcadiascience.com

12 Feb 2025

Happy Darwin Day! Today, we’re thinking about how to use evolution to accelerate biomedical research. We think the answer is to expand the repertoire of organismal models. Search for the best ones using our new portal, Zoogle: zoogle.arcadiascience.com 🧵

research.arcadiascience.comRescuing Chlamydomonas motility in mutants modeling spermatogenic failureWe used Chlamydomonas reinhardtii motility mutants with disrupted genes homologous to human SPEF2 or DNALI1 to model spermatogenic failure disorders SPGF43 and SPGF83, respectively. We recovered aspec...

17 Dec 2024

Today at #CellBio24, I'll discuss our new pub at the "Quantitative Biology in Emerging Model Systems" subgroup session at 5:15 pm in Ballroom 20A. Come check it out!

Cameron Dale MacQuarrie@cdmacquarrie.bsky.social

🧵 New from @arcadiascience.bsky.social: We used Chlamydomonas mutants to model specific types of spermatogenic failure and found drugs can rescue swimming behavior in mutation-specific ways. Full pub: research.arcadiascience.com/pub/result-chlamy-spgf [1/8]

zenodo.orgG-P Atlas: a neural network for hollistically mapping genotypes to phenotypes

17 Dec 2024

Today at #CellBio24, Dave Mets will be at poster B599 talking about mapping genotypes to phenotypes! poster: zenodo.org/records/1449...

Arcadia Science@arcadiascience.com

Come find us at #CellBio24! Our CSO @pracheeac.bsky.social is giving a talk today, and then we've got another talk and a bunch of posters during the rest of the conference. Come say hey!

zenodo.orgRescuing Chlamydomonas Motility in Mutants Modeling Spermatogenic FailurePoster file created for CellBio2024 (ASCB / EMBO) based on the pub Essock-Burns T, Lane R, MacQuarrie CD, Mets DG. (2024). Rescuing Chlamydomonas motility in mutants modeling spermatogenic failure. ht...

Our new pub dropped this weekend! For those at #CellBio24, I'll be at poster B73 starting at 11:15 am discussing this work! I'll also be giving a talk on Tuesday at 5:15 pm in Ballroom 20A in the Quantitative Biology in Emerging Model Systems session poster here: zenodo.org/records/14481493

Cameron Dale MacQuarrie@cdmacquarrie.bsky.social

github.comGitHub - Arcadia-Science/2024-chlamy-mutant-motility-pub at v1.0Collection of data, code, scripts, and notebooks accompanying the pub "Rescuing Chlamydomonas Motility in Mutants Modeling Spermatogenic Failure." - GitHub - Arcadia-Science/2024-chlamy-m...

While this project is now on ice (explained in pub), all code & data are available: 🔗 GitHub: (github.com/Arcadia-Scie...) 📊 BioImage Archive: (www.ebi.ac.uk/biostudies/b...). [7/8]

Thanks to the team at @arcadiascience.bsky.social! Especially @taraeb.bsky.social, Ryan Lane, Dave Mets, @meganhoch.bsky.social, & Audrey Bell who made this work possible! Check out the pub here (research.arcadiascience.com/pub/result-chlamy-spgf) & feel free to comment! We love feedback! [8/8]

Despite similar motility defects, the mutations responded differently to treatment —- what rescued one mutation often had no effect on the other. This suggests mutation-specific therapeutic approaches are needed [5/8]

The different effects of each drug highlight how similar swimming problems can arise from distinct molecular pathways. What works for one genetic variant may not work for another [6/8]

These mutants were characterized decades ago and show similar swimming defects to those seen in SPGF patients' sperm. Our phylogenetic framework showed they're excellent models for SPGF83 and SPGF43 [3/8]

We developed two complementary approaches to measure motility: a population "sink-or-swim" assay and detailed single-cell tracking with SwimTracker (research.arcadiascience.com/pub/resource-swimtracker-htp-swimming-assay/release/2). This revealed how drugs affect different aspects of swimming [4/8]

We used phylogenetic analysis from our pub led by Ryan York, Austin Patton & @pracheeac.bsky.social (research.arcadiascience.com/pub/result-evolutionary-organismal-selection) and found Chlamydomonas proteins have high conservation with SPGF proteins. [2/8]

Tomorrow at #CellBio24, I'll be at poster (B73) talking about some fun new work we just released using Chlamydomonas to model spermatogenic failure. Check out the poster here: zenodo.org/records/14481493 Join the fun and post your comments & questions on the pub! bit.ly/chlamy-spgf

Arcadia Science@arcadiascience.com

Come find us at #CellBio24! Our CSO @pracheeac.bsky.social is giving a talk today, and then we've got another talk and a bunch of posters during the rest of the conference. Come say hey!

bit.lyLeveraging evolution to identify novel organismal models of human biologyResearching just a handful of organisms limits biological discovery. We developed an approach pairing organisms with biological questions to expand research biodiversity.

Happening soon at #CellBio24 @ascbiology.bsky.social Ryan York's poster (B574) on a data-driven approach to selecting your model organism @arcadiascience.bsky.social Poster here: zenodo.org/records/14479386 Join the fun & post your comments & questions on the pub! bit.ly/evolutionary...

Arcadia Science@arcadiascience.com

Come find us at #CellBio24! Our CSO @pracheeac.bsky.social is giving a talk today, and then we've got another talk and a bunch of posters during the rest of the conference. Come say hey!

Cameron Dale MacQuarrie reposted

Prachee Avasthi

@pracheeac.bsky.social

Replying to @pracheeac.bsky.social

Ryan’s poster: zenodo.org/doi/10.5281/... The concept: research.arcadiascience.com/pub/idea-sel... The approach and analyses: research.arcadiascience.com/pub/result-e... The validation: research.arcadiascience.com/pub/result-c...

Cameron Dale MacQuarrie reposted

Prachee Avasthi

@pracheeac.bsky.social

Joseph W. BRRRAAAIIINNNSSS

If you’re at #CellBio2024 drop by Ryan’s poster today (Board B574) to hear the latest from @arcadiascience.bsky.social about how you can choose the right model system for your research or find areas best studied in the species you have expertise/infrastructure Poster and publications below

Cameron Dale MacQuarrie reposted

@josephwb.bsky.social

19 Oct 2024

Annual reminder that PhyloPic is your free go-to source for organismal silhouettes for #Jack-o'-lantern designs phylopic.org @tmkeesey.bsky.social 🧪

phylopic.orgPhyloPicPhyloPic is an open database of free silhouette images of animals, plants, and other life forms, available for reuse under Creative Commons licenses. Download silhouettes for use in educational materi...

research.arcadiascience.comPhenotypic differences between interfertile Chlamydomonas species · Genetics: Decoding evolutionary...We’re crossing C. reinhardtii and C. smithii algae for high-throughput genotype-phenotype mapping. In preparation, we’re comparing the parents to uncover unique species-specific phenotypes.

Two weeks ago we @arcadiascience.bsky.social posted our final, major update to our Chlamydomonas sp. phenotypic variation pub! research.arcadiascience.com/pub/result-c...! A lot of new findings in the 🧵!!! 1/9

twitter.comTweet by @TaraEssockBurns

Plus, check out the insanely cool findings on differences in motility patterns and organelle morphology between the species in this Twitter/X thread! 8/9 twitter.com/TaraEssockBu...

Find all of our findings, code, and data at research.arcadiascience.com/pub/result-c... We’re eager to get your feedback on this work! Please post any thoughts, questions, or concerns on our pub!

doi.orgInfluence of Cell Wall on Biomolecules Biosynthesis in Chlamydomonas reinhardtii Strains Exposed to ...The application of magnetic fields (MF) has attracted the attention of researchers due to their efficiency to change cell metabolism. Chlamydomonas reinhardtii is a biotechnologically useful microalga...

But now it gets a bit weird! We read a recent study that indicated C. reinhardtii cell wall mutants have reduced growth in magnetic fields doi.org/10.1007/s00284-023-03189-0 6/9

We designed a 96-well plate magnetic field block. Surprisingly, after a week of growth on the block, we were able to clearly distinguish between these two species, consistent with C. smithii having a thinner cell wall! 7/9

We started by staining the two species with calcofluor-white, which binds to cell wall components. Our analysis showed thicker staining in C. reinhardtii, consistent with C. smithii having a weaker wall (analysis in the pub!)! 4/9

But this method is low-throughput, so instead, we grew cells w/ Congo red, which is toxic to cell wall (cw) mutant yeast. It wasn’t sensitive enough to distinguish btw the two WT species, but we saw less growth in cw mutants, so this is a decent assay to find algal cw mutants 5/9

First update! Although we’ve seen C. smithii adapting to a wide range of media, these cells are more sensitive to a harsh antibiotic-fungicide cocktail! 2/9

We’d also found that C. smithii is more sensitive to detergent, which could indicate less environmental protection. We’ve adapted this protocol to work in a 96-well plate. These findings led us to compare the cell wall of the species. 3/9

1 Dec 2023

🎉 Excited to share our latest work at #CellBio23! I'll be presenting a poster on our pub “Phenotypic differences between interfertile Chlamydomonas species” and our continued work in the Protists and Parasites Cell Biology poster session (Board #723) @arcadiascience.bsky.social

ascb2023.arcadiascience.comArcadia Science | ASCB 2023Arcadia Science is heading to #cellbio2023! On this page, you can see what we’ll be up to, when/where you can find us, and check out all the science we’re sharing, including poster PDFs and links ...

1 Dec 2023

Our work is most valuable when accessible to all, so find the poster at ascb2023.arcadiascience.com and the pub at bit.ly/chlamy-parents. We’re always looking for feedback and are especially interested in ideas of what traits we could test so please consider commenting on our pub!