Rob Parton

JCS cover: Actin forms a supracellular network at the apical side of squamous epidermoid cells. Actin filaments are colour-coded according to their position along the z-axis, revealing the three-dimensional organization and continuity of the apical actin cortex across neighbouring cells. See article by L. Marpeaux et al. (jcs264424).

Issue 4 is complete

Explore our Toc: journals.biologists.com/jcs/issue/13...

Our cover image shows the apical supracellular actin network in squamous epidermoid cells. Actin filaments are colour-coded according to z-position. See article by Marpeaux et al.
journals.biologists.com/jcs/article/...

Two postdoc positions in way lab go live tomorrow......please pass the message along.......more details to follow.

Feeding-regulated glycogen metabolism drives rhythmic liver protein secretion - Nature Metabolism Hepatic glycogenolysis is essential for protein glycosylation and rhythmic secretion by the liver. Disruptions to hepatic glycogenolysis, caused by congenital diseases or physiological factors such as...

Our study is out today 🎉 in @natmetabolism.nature.com. The liver doesn’t secrete proteins nonstop; it follows a daily rhythm. Meal timing controls liver protein release via glycogen metabolism, and disrupted eating blunts these rhythms. A 🧵 ...

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After 15 years as Editor-in-chief (EiC), Michael Way @drmichaelway.bsky.social will be stepping down at the end of 2026 & we are seeking feedback from the cell biology community as part of the consultation process for appointing a new EiC.
We'd love to hear from you: www.surveymonkey.com/r/GZCC9F9

First day back at work for 2026, and excited to share that @gurgaganveer's first paper from his PhD has been published in @acsnano!

If you are interested in the biology of endosomal escape & strategies for enhanced delivery of therapeutics, check it out: bit.ly/4roRcnp

Do you want to know more about how Retromer regulates Rab7 activity in yeast? Of course you do. Check out the new collaboration with Andreas Mayer with work led by Catarina Alves and Kevin Chen.

Our preprint on mural cells and the zebrafish blood brain barrier is now revised with new data and analysis

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

Medical Research Matters

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9. Altogether, we show that trans-endothelial transport of PEG-based nanoparticles is size-dependent, dictating intracellular or intercellular routes, and further constrained by vesicle size limits and the level of activity of distinct intracellular pathways.

8. Cavin1 paralog is widely expressed across the zebrafish vasculature up to 15 dpf. Examination on Cavin1 double KOs show that caveolae do not mediate PEG-based NP transvascular transport in the zebrafish, and caveola loss similarly does not alter NP biodistribution in mice.

7. As the PEG-based micelles increased in size to 109 nm, low basal macropinocytosis becomes the dominant trans-endothelial transport pathway, with minimal dynamin-dependent contribution, likely due to vesicle size constraints.

6. We then examined the trans-endothelial transport pathways of 32 to 81 nm PEG-based micelles. These NPs extravasate via dynamin-dependent pathways, with some contribution from the macropinocytic pathway.

5. Having mapped these physiological pathways, we injected zebrafish embryos and juveniles with PEG-based NPs. Small (3-7 nm) PEG-based hyperbranched polymers (HBPs) rapidly extravasate via paracellular routes as determined by cAMP treatment, with minimal intracellular contributions.

4. Next, we identified steady-state extravasation pathways by priming vessels with inhibitors and using a Cavin1 KO. Fluid-phase solutes cross the embryonic endothelium via paracellular routes (≤15 nm), dynamin-dependent mechanisms, and low basal macropinocytosis, with minimal caveola contribution.

3. We discovered that trans-endothelial transport involves dynamic intracellular vesicles within intersegmental vessels (ISVs). These endocytic vesicles localize to venous ISVs and appear influenced by arterial-venous mechanical diffs, which we probed by modulating shear stress with epinephrine.

2. Co-injecting 2000 kDa dextran with NPs allowed us to 1. control injection variability, 2. flag embryos with abnormal leakage, 3. parse vascular vs EVS regions and 4. provide a normalization reference for unbiased quantitation. As a proof of concept, we quantified 40 kDa dextran extravasation.

1. First, we set up a standardized protocol to assess trans-endothelial transport. We looked at NP signal changes in the blood vessels and extravascular space (EVS) and thought that co-injecting a tracer would be an ideal control. We surveyed dextran tracers across a range of sizes.

Trans-Endothelial Trafficking in Zebrafish: Nanobio Interactions of Polyethylene Glycol-Based Nanoparticles in Live Vasculature Trans-endothelial transport of nanoparticles remains poorly characterized in live organisms. The zebrafish is a well-established model for direct in vivo imaging; however, standardized controls have n...

How do nanoparticles traverse the endothelial barrier in a living organism? We explored this fundamental question using the zebrafish and PEG-based nanoparticles (NPs) in our latest article: (pubs.acs.org/doi/10.1021/...).

4. The high specificity of caveospheres in delivering highly toxic molecules to tumor cells in mice highlights the potential for utilizing caveospheres in chemotherapeutic targeting of cancer cells as well as in imaging and diagnosis.

3. The caveospheres can be further engineered to mimic virus particles, with the spike protein of SARS-Cov-2 used to target a human bronchial epithelial cell line.

2. The Z-domain displayed on the surface of caveospheres provides a specific antibody-binding site, allowing modular labelling and targeting to defined cell types, including hard-to-transfect T cells.

1. Caveospheres can incorporate genetically-encoded cargo proteins without protein purification or can be loaded with RNA, DNA, proteins, drugs.

A Modular Encapsulation System for Precision Delivery of Proteins, Nucleic Acids, and Small Molecules Targeted nanoparticles have the potential to revolutionize therapeutics for medical applications. Here, we demonstrate the utility of a flexible precision nanovesicle delivery system for functional de...

Excited to share our work engineering caveolin-derived nanoparticles “caveospheres”. We show their use for targeted transfection in cultured cells and effective targeted delivery and tumor killing in vivo.
pubs.acs.org/doi/full/10....

Latest issue of Cowrent Biology is up! www.cell.com/current-biol...

James, J., Winn, L. B., Mottram-Epson, P., & Köster, D. (2025). Paths to stability–actin regulation of adherens junction mechanics. Journal of Cell Science, #EpitheilalMechanicsReview doi.org/10.1242/jcs....

At the helm of JCS – Editors-in-Chief past, present… and future The Editor-in-Chief (EIC) of Journal of Cell Science plays a key role in defining the overall vision of the journal, helping to decide on journal strategy, policy and priorities, and overseeing all co...

What's it like being Editor-in-chief of @jcellsci.bsky.social? doi.org/10.1242/jcs....

The winning microscopy images from the Node–FocalPlane image competition, held at the Biologists @ 100 conference in March 2025. Left, ‘Cell-estial bloom’, the first-place winner, from Özge Özgüç, showing a live human induced pluripotent stem cell (hiPSC) colony labelled for lamin B, marking the nuclear lamina. Centre, ‘Dancing actinotroch’, the second-place image, from Allan Carrillo-Baltodano, showing an actinotroch larva of a phoronid worm, stained for actin (phalloidin, yellow) and acetylated tubulin (magenta). Right, ‘Who's active?’, the third-place image, from Julia Peloggia de Castro, depicting a lateral view of a zebrafish embryo at 9 h post fertilisation. MitoTracker was used to stain active mitochondria (magenta to yellow intensity scale), and an EGFP transgenic tag marks cell membranes (cyan).

In their Editorial, Claire Moulton, Amelia Glazier and Katie Ward look back on an extraordinary year, as @biologists.bsky.social celebrated their 100-year anniversary.

journals.biologists.com/jcs/article/...

Meet the JCS editors - Michael Way, Seema Grewal and Amelia Glazier

Attending #CellBio2025? Have questions about publishing with Journal of Cell Science? Meet the @jcellsci.bsky.social Editors on Monday 8 December, 14:00 -16:00 pm at booth 1232.

Imaging Cell Dynamics 11-14 May 2026 Montanyà Hotel, Catalonia, Spain Register now - early-bird deadline: 16 January 2026 Journal of Cell Science Meeting

Registration is now open to attend Journal of Cell Science's meeting on Imaging Cell Dynamics, organised by Francesca Bottanelli, Guillaume Jacquemet, Michael Way and Giulia Zanetti.

Find out more: biologists.com/meetings/jcs...

#JCSimaging #Microscopy #Microscope #Imaging #Cells #CellScience

Postdoctoral Research Assistant - MCDB - UOD2016 Closing date: Thursday 6 November 2025, 23:59

Attention membrane traffickers! I'm recruiting a post-doc to my lab in Dundee. We're dissecting the functions of intrinsically disordered domains of COPII coat proteins. We think they control timing of coat assembly and morphology of carriers.

www.dundee.ac.uk/work-for-us/...