Tomas Janovic

New pre-print from the lab! Lead by Mariia Mikhova and in collaboration with Kefei Yu’s lab @msumgi.bsky.social we dug into the molecular mechanism of class switch recombination in B cells using simultaneous RNA and protein single-molecule imaging. 1/n
www.biorxiv.org/content/10.6...

Big congratulations, Sebastian! It was a pleasure meeting the whole group.

First test of live-cell single-molecule imaging in a new lab and it looks very promising!!!

Thanks to @ceitec-cellimcf.bsky.social instruments at
@ceitec.eu and @masarykuniversity.bsky.social. 🙌

#microscopy #singlemolecule #livecell #newlab

79 | Maria Leptin and creativity in grant writing - Night Science Maria Leptin is the President of the ERC, the European Research Council, and Professor of genetics at the University of Cologne. In this episode, Maria describes her own path as one driven by observat...

What is actually a high-risk, high-gain project proposal?
Great to hear the answer directly from the ERC president Maria Leptin.

🎧 nightscience.buzzsprout.com/1744020/epis...

Night Science (@nightsciencepod.bsky.social) is simply an amazing podcast for scientists!

#ERC #NightScience #GrantWriting

I’m excited to share that #CzechBioImaging selected my project for funding to establish live-cell single-molecule imaging at the @ceitec-cellimcf.bsky.social core facility at @ceitec.eu , @masarykuniversity.bsky.social !

Can’t wait to bring this technology to Brno! 🔬✨

GRANTS WEEK | Grants Week 25 - 27 November 2025 (Komenského nám. 2, Roger Scruton Hall)

Huge thanks to @masarykuniversity.bsky.social for organizing Grants Week! Hearing from holders of prestigious EU grants and learning from their experiences was very inspiring.
www.grantsweek.muni.cz

Ku limits aberrant mRNA splicing promoted by intronic antisense Alu elements Alu elements are short repeats that occupy approximately 10% of the human genome. Saturation of primate genomes with Alu sequences occurred at the prosimian/new-world monkey evolutionary juncture. Alu...

New Print Alert! A fun collab with Kathy Meek at MSU. Led by talented bioinformatician Giovanni Pascarella we demonstrate that Ku70/80 binds intronic antisense Alu elements to inhibit cryptic splice sites. For details see the thread below! 1/n

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

IT'S HAPPENING! 💥 I'm psyched to launch the collaboration between @qedscience.bsky.social & @openrxiv.bsky.social @biorxivpreprint.bsky.social! Preprint + q.e.d = your science is out there, and anyone can appreciate it. Let's care about making discoveries, and not on “getting published” (1/3) 👇

Human RPA is an essential telomerase processivity factor for maintaining telomeres Telomerase counteracts telomere shortening by repeatedly adding DNA repeats to chromosome ends. We identified the replication protein A (RPA) heterotrimer as a telomerase processivity factor critical ...

Our paper in Science is out! @souravagrawal.bsky.social, @rlynn.bsky.social, @susvirkar.bsky.social, and the rest of the team show human RPA is a telomerase processivity factor essential for telomere maintenance. This reshapes our thinking about telomerase regulation. www.science.org/doi/10.1126/...

Antiviral reverse transcriptases reveal the evolutionary origin of telomerase Defense-associated reverse transcriptases (DRTs) employ diverse and distinctive mechanisms of cDNA synthesis to protect bacteria against viral infection. However, much of DRT family diversity remains ...

1/10 Genome maintenance by telomerase is a fundamental process in nearly all eukaryotes. But where does it come from?

Today, we report the discovery of telomerase homologs in a family of antiviral RTs, revealing an unexpected evolutionary origin in bacteria.
www.biorxiv.org/content/10.1...

Our new preprint is up! This is the main postdoc work of @wiesner-t.bsky.social focusing on exocytosis along the axon shaft and its regulation by the sub membrane actin-spectrin scaffold: www.biorxiv.org/content/10.1...
Read the thread below for a summary of our findings 🧵1/11

Together, our results reveal that shelterin is not a single static complex but two functional subcomplexes with distinct dynamics. Both subcomplexes are dimeric and bind every other telomeric nucleosome.

Building on this model, we demonstrate that TRF1 and TRF2 bind non-overlapping sites on telomeric chromatin, as they can’t compete each other from telomeres. Consistent with an in vitro observation by Hu et al. from @kellythd-nguyen.bsky.social group.

However, TRF2 and RAP1 are very dynamic, providing an evidence that shelterin exists predominantly at two distinct subcomplexes.

Using single-molecule imaging in living cells, we found that TRF1, TIN2, TPP1 and POT1 subunits display static behavior – tightly bound to telomeres.

We found ~25–30 copies of each shelterin protein at telomeres in HeLa cells. Surprisingly, in HeLa 1.3 cells with telomeres 5× longer, the number rises only modestly (~40), suggesting shelterin is more sparsely distributed on longer telomeres.

Chromosome ends are protected by shelterin complex, but its precise composition and dynamics remain unclear. Using CRISPR genome editing, we tagged all shelterin components at endogenous loci to define their telomeric copy number and dynamics—uncovering key insights into genome stability.

TRF1 and TRF2 form distinct shelterin subcomplexes at telomeres The shelterin complex protects chromosome ends from aberrant DNA repair and regulates telomerase access to telomeres. Shelterin is composed of six pro…

🚨 Excited to share my main postdoc work from the @jenscs83.bsky.social lab, now out in Cell Reports! 👉 www.sciencedirect.com/science/arti... We dissect how shelterin proteins organize at telomeres in human cancer cells—revealing distinct subcomplexes that maintain chromosome ends. 🧵

SNAP-tag2 for faster and brighter protein labeling - Nature Chemical Biology SNAP-tag is a widespread tool for labeling protein for bioimaging. Now, Kühn et al. report SNAP-tag2 with increased labeling kinetics and brightness, which translates into a better performance in live...

Finally out in Nature Chem Bio:
SNAP-tag2 for faster and brighter protein labeling
www.nature.com/articles/s41...
Thank you Steffi and Veselin.

Super-resolution imaging in whole cells and tissues via DNA-PAINT on a spinning disk confocal with optical photon reassignment - Nature Communications Zaza and colleagues demonstrate that DNA-PAINT on a spinning disk confocal microscope with optical photon reassignment enables high-resolution imaging across large fields and imaging depths, resolving...

Great new DNA/Q-Paint method published by our @ucl colleague Sabrina Simoncelli - lucky to have been part of it! Check out the Ecadherin and collagenIV imaging in the fly retina at up to 15micron depth www.nature.com/articles/s41...

A palette of bridged bicycle-strengthened fluorophores - Nature Methods A suite of bridged rhodamine dyes (BriDyes) offers excellent brightness, solubility, photostability, and tunable cell permeability along with resistance to photoblueing, making them exceptional all-pu...

Here come our new palette of fluorescent dyes. The BD dyes endeaves to balance glowy brightness, robust photostability, and biocompatibility. Let's boost 4D dynamic super-resolution imaging!!!
www.nature.com/articles/s41...
@spirochrome.com

Choose Europe for Science: ERC welcomes new budget for 'super grants' The Scientific Council of the European Research Council welcomes the offer of substantial additional budget from the European Commission for the development of a new ERC funding instrument offering la...

The ERC welcomes the offer of substantial additional budget from @ec.europa.eu for the development of a new ERC funding instrument offering larger, longer-term grants, as announced by President Ursula Von der Leyen at the Sorbonne this morning.

👉 europa.eu/!NTYTTV

A great end to another Telomeres CSH meeting! It was nice to see and discuss science with many colleagues. With @cijilim.bsky.social @jenscs83.bsky.social, Stone, Nandakumar, Zappulla labs at banquet

🚨🔬💗Whether investigating cell organelles or mapping proteins, together with Victor Puelles's lab we lay a roadmap for selecting optimal #ExM and #SuperResolution #microscopy combinations. Daria Aristova and Dominik Kylies review with amazing co-authors

pubs.aip.org/aip/apr/arti...

Very nice work!

Excited to share our preprint on the molecular architecture of heterochromatin in human cells 🧬🔬w/ @jpkreysing.bsky.social, @johannesbetz.bsky.social,
@marinalusic.bsky.social, Turoňová lab, @hummerlab.bsky.social @becklab.bsky.social @mpibp.bsky.social

🔗 Preprint here tinyurl.com/3a74uanv

Our new findings on how chromosomes get ready for cell division are now published in @cellpress.bsky.social!

Congratulations, Kai, @andibrunner.bsky.social and everyone else involved! 🤩

www.sciencedirect.com/science/arti...

A CPC-shelterin-BTR axis regulates mitotic telomere deprotection - Nature Communications Here the authors reveal how telomeres signal mitotic stress. A key protein network alters their structure exposing telomere ends to signal mitotic stress, ultimately triggering a controlled DNA damage...

1/Out today in @naturecomms.bsky.social,

“A CPC-shelterin-BTR axis regulates mitotic telomere deprotection”.

Here we identify the mechanism that unwinds telomere-loops (t-loops) during mitotic arrest to activate the DNA damage response and signal mitotic stress.

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

#Hiring! The postdoctoral position in my lab at Pharm Chem KU is open!! This is an NIH-funded position to work on cytochrome P450 metabolism using a combination of mass spectrometry proteomics and live-cell imaging.
employment.ku.edu/staff/29681BR

The PST repeat region of MDC1 is a tunable multivalent chromatin tethering domain DNA double strand breaks (DSBs) are widely considered the most cytotoxic DNA lesions occurring in cells because they physically disrupt the connectivity of the DNA double helix. Homologous recombinati...

Super excited to share our most recent pre-print, lead by K99 fellow @heyzajr.bsky.social, who will be starting his own lab at Wayne State University in February!

The question is how are DNA breaks held together during HR?? 1/n

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