Zeshi Li (Jack)

In memoriam: Hans Vliegenthart In memoriam: prof. dr. Hans Vliegenthart (April 7, 1936 – February 12, 2026)

RIP: Professor Dr. Johannes Frederik Gerardus (Hans) Vliegenthart (April 7, 1936 – February 12, 2026)
A leading figure in structural Glycobiology.

www.uu.nl/en/news/in-m...

Science update from my postdoc Peiyuan Chai - his work “glycoRNA complexed with heparan sulfate regulates VEGF-A signaling” is now published @nature.com uncovering a new layer or glycoRNA-regulation of growth factor mediated control physiological processes rdcu.be/e1bBX

Thanks Alexander!

This project was co-led by former post-doc of Chirlmin Joo @chirlmin.bsky.social lab, Bhayashree Joshi. Jointly supervised by Vered Raz (LUMC).

A molecular trio anchors RNAs on the cell surface RNAs are now recognized as functional components of the cell surface, expanding the molecular repertoire of the plasma membrane. In this issue of Mole…

Nice Preview from Ling-Ling Chen lab at Shanghai Academy of Natural Sciences. www.sciencedirect.com/science/arti...

Cell-surface RNA forms ternary complex with RNA-binding proteins and heparan sulfate to recruit immune receptors Recent discoveries have shown the presence of ribonucleic acid (RNA) on the cell surface, defying the view that RNA only functions intracellularly. Ho…

Link to the paper: www.sciencedirect.com/science/arti...

How are RNAs presented on the cell surface without any transmembrane domains? In our paper published at Molecular Cell @cp-molcell.bsky.social, we provide mechanistic insights into this pressing question. They form ternary complexes with RNA-binding proteins and heparan sulfate proteoglycans.

Now finally peer-reviewed and published in @springernature.com Experimental & Molecular Medicine (EMM)🥳:
www.nature.com/articles/s12...

Our story was published back-to-back with the intriguing paper by Kim et al.:
www.nature.com/articles/s12...

Had the pleasure to learn about this cool platform over a Friday afternoon seminar during Matt’s visit at UU.

Chemoenzymatically Synthesized O‐Acetylated GD3 Gangliosides to Examine Viral Receptor Specificities in a Cellular Context 7-O-, 9-O-, and 7,9-di-O-acetylated GD3 gangliosides can be prepared by chemical assembly of a tetrasaccharide as α-glycosyl fluoride that is coupled to sphingosine using a glycosynthase, followed by...

New @angewandtechemie.bsky.social paper jointly supervised by Zeshi Li @lizeshi.bsky.social and Geert-Jan Boons describes the chemoenzymatic synthesis of O-acetylated GD3 as intact glycolipids, and the use there of to study virus binding in cellular context.
onlinelibrary.wiley.com/doi/10.1002/...

Our studies call for development of labeling and analytical methods that are really SPECIFIC for glycoRNA.

Team effort with Sungchul Kim lab, @chirlmin.bsky.social Joo lab, and @pmiesen.bsky.social Miesen lab

These glycoproteins behave like glycoRNA biochemically and electrophoretically, so it may confound assays on glycoRNA. E.g. when doing #glycomics analysis, how much glycans are from the contaminant glycoproteins vs. from glycoRNA? This will critically affect your conclusions

We show that the total #RNA isolated from cell cultures can contain substantial non-RNA glycoconjugates, which was found out to be #glycoproteins (characterized in Kegel et al paper), and those glycoconjugates persist even after protease treatment and rounds of purification.

#glycotime We hope our b2b publications serve as a heads-up for the #glycoRNA community, and drive the field forward constructively. Links👇
Kim et al. rdcu.be/eP4GQ
@nathanaelbkegel.bsky.social Kegel et al. nature.com/articles/s12276-025-01575-1 (Stefan Bauer lab)

It’ll be interesting to explore whether there are interacting proteins specifically recognizing sialate OAc moieties, or how specific gangliosides cluster with different membrane proteins on cell surface or organelles.

Regarding where they may play a role, in addition to cell surface, previous literatures suggest gangliosides can function intracellularly in mitochondria and very likely Golgi. Langereis et al 2016 paper showed OAcSias largely colocalizes with Golgi markers.

Thanks for the question, Chris! How the OAc gangliosides function at molecular level is still largely unknown. We generally believe the sialate OAc group blocks lectin or enzyme recognition. But there has not been any endogenous protein that specifically binds OAcSia or these gangliosides.

33 million euro investment for national electron microscope facility EMPower A major new national facility for electron microscopy, called EMPower, has been awarded to a consortium of Dutch universities and medical centers. EMPower aims to pave the way for major discoveries im...

Very happy that NWO supports this major upgrade of our national EM infrastructure. It is great that this initiative got broad support all over NL, and it will EMPower fantastic science - looking forward to that!
www.uu.nl/en/news/33-m...

Thrilled, and admittedly relieved, to see this major investment in Dutch #cryoEM become reality! 🇳🇱🔬

Honoured to be a co-applicant on this national initiative and very excited for the opportunity to advance our work in cellular structural virology! 🦠

www.uu.nl/en/news/33-m...

Deeply honored to be a co-applicant of #BioBeyond_NL. The team will develop enabling #MassSpec based technologies to advance (glyco)proteomics, glycomics and spatial omics.
Stay tuned for PhD/post-doc openings in the near future!

www.nwo.nl/en/news/nati...

Congratulations to CBDD researchers, Geert-Jan Boons and Zeshi Li @lizeshi.bsky.social, and members of #BioBeyond_NL, a consortium co-led by Maastricht, Utrecht, Radboud University and LUMC researchers to advance (glyco)proteomics, glycomics and spatial omics. Read more👇
www.nwo.nl/en/news/nati...

Advancing #glycoRNA imaging with FRET-based detection and expanding the scope of their presentation to extracellular vesicles - interestingly high levels of sialoglycoRNAs on blood EVs can be predictive of having cancer @naturecomms.bsky.social

www.nature.com/articles/s41...

SCAM ALERT. This is a fake conference that ripped off my and other people’s names to trick people into registering. There is no such conference that I or the others shown were invited or agreed to. We are working to try to get this fraud taken down from the web.

chemsymposia.com

There is an interesting read here (posted shortly after the very first preprint): doi.org/10.1242/prel...

Question for glycoRNA proponents: What specific evidence would convince you that these signals are protein contaminants rather than modified RNA? Since so much evidence depends on extraction & analysis of pure RNase-sensitive glycoRNA, this seems like a problem.

Worth reading the whole exchange ⬇️

RNA-Associated Glycoconjugates Highlight Potential Ambiguities in glycoRNA Analysis A recent ground-breaking study suggested that small RNA from mammalian cells can undergo N-glycan modifications (termed glycoRNA) 1. The discovery relied upon a metabolic glycan labeling strategy in c...

Hi Dr. Erasmus, here is an updated version: www.biorxiv.org/content/10.1...

Proteins are a source of glycans found in preparations of glycoRNA Recent discoveries show that RNA can be modified with sialylated glycans (termed glycoRNA), thus broadening our understanding of cellular glycosylation beyond traditional proteins and lipids. However,...

An independent study from @nathanaelbkegel.bsky.social et al. has led to alike conclusions. The common RNA prep may not give you the RNA as pure as you think. The results also call for the development of glycoRNA-specific labeling methods… A dual labeling?

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

Suppose you are ready to load the glycan-labeled glycoRNA samples into gels. Get half of it, mix with RNases/nucleases, incubate, add sample loading buffer, denature, DIRECTLY load the mixture into gel. Do the rest the same as reported. GlycoRNA gets degraded, the N-glycoconjugate remains intact.

We hope this serves as a heads-up for the community, and propose a simple checkpoint experiment for whichever protocol you are employing👇

The non-RNA N-glycoconjugate, is an independent, separate, but potentially co-existing molecular entity in glycoRNA preparations. It even exhibits an apparent RNase sensitivity related to purification methods, but not digestion.