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Tomas Janovic

@janovictom.bsky.social

310 followers 730 following 17 posts

Postdoc at Masaryk University, Brno, Czechia | Advanced microscopy, Single-molecule biophysics, Telomeres, Genome maintenance.

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Reposted by Tomas Janovic

Christophe 🔬 L @christlet.bsky.social · 22d

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

Tomas Janovic @janovictom.bsky.social · Aug 25

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.

Tomas Janovic @janovictom.bsky.social · Aug 25

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.

Tomas Janovic @janovictom.bsky.social · Aug 25

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

Tomas Janovic @janovictom.bsky.social · Aug 25

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

Tomas Janovic @janovictom.bsky.social · Aug 25

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.

Tomas Janovic @janovictom.bsky.social · Aug 25

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.

Tomas Janovic @janovictom.bsky.social · Aug 25

🚨 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. 🧵

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…

www.sciencedirect.com

Reposted by Tomas Janovic

Kai Johnsson @kjohnsson.bsky.social · Jul 3

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

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...

Reposted by Tomas Janovic

Franck Pichaud @fpichaud.bsky.social · May 29

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...

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...

Reposted by Tomas Janovic

Zhixing Chen @zhixingchen2.bsky.social · May 20

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

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...

Reposted by Tomas Janovic

European Research Council (ERC) @erc.europa.eu · May 5

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

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...

Reposted by Tomas Janovic

Kelly Nguyen @kellythd-nguyen.bsky.social · May 4

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

Reposted by Tomas Janovic

Ricardo Henriques @henriqueslab.bsky.social · Apr 25

🚨🔬💗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...

Tomas Janovic @janovictom.bsky.social · Apr 12

Very nice work!

Reposted by Tomas Janovic

Sergio Cruz-León @sergiocruzleon.bsky.social · Apr 11

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

Reposted by Tomas Janovic

Ellenberg Lab @ellenberglab.bsky.social · Mar 24

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...

Reposted by Tomas Janovic

Tony Cesare @thecesarelab.bsky.social · Mar 17

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....

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...

Reposted by Tomas Janovic

Carlo Barnaba 🇮🇹🇲🇽 @barnabalab.bsky.social · Jan 23

#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

Postdoctoral Researcher - University of Kansas - Job Details

Job Details: A full-time Postdoctoral Research Associate position is available at the University of Kansas Department of Ph

employment.ku.edu

Reposted by Tomas Janovic

Jens Schmidt @jenscs83.bsky.social · Jan 13

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...

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...

www.biorxiv.org

Reposted by Tomas Janovic

Tony Cesare @thecesarelab.bsky.social · Jan 13

1/Delighted to announce the newest paper from our lab, “Homologous recombination promotes non-immunogenic mitotic cell death upon DNA damage”, is out today in @naturecellbiology.bsky.social, www.nature.com/articles/s41....

Homologous recombination promotes non-immunogenic mitotic cell death upon DNA damage - Nature Cell Biology

Szmyd et al. show that DNA repair pathways impact whether cells with DNA lesions arrest in mitosis. The formation of homologous recombination-driven double Holliday junctions elicits mitotic cell deat...

Reposted by Tomas Janovic

Claire Deo @clairedeo.bsky.social · Jan 7

We made a photoswitchable HaloTag (psHaloTag), which can reversibly turn-on fluorogenic dyes upon illumination 💡. Congrats to Franzi, Bego and all co-authors, check out our preprint below 👇
www.biorxiv.org/content/10.1...

Tomas Janovic @janovictom.bsky.social · Dec 24

8/8 I’d like to thank to @jenscs83.bsky.social for having a chance to work on this interesting and important topic in telomere biology! We’d like to hear your feedback and questions regarding our results. Please, share this work with others.

Tomas Janovic @janovictom.bsky.social · Dec 24

7/8 We proposed a model of telomeric architecture in HeLa cells. The shelterin associates with telomeres in a form of two distinct subcomplexes: TRF1-TIN2-TPP1-POT1 and TRF2-RAP1. Both subcomplexes are dimeric and are equally presented at telomeres binding approximately every other nucleosome.

Tomas Janovic @janovictom.bsky.social · Dec 24

6/8 We also probed the shelterin recruitment to telomeres hierarchy using a selective degradation Halo-PROTAC system. Not only TIN2 and POT1 recruitment to telomeres is dependent solely on their association with TRF1, but we found that TRF1 and TRF2 occupy distinct binding sites on telomeres.