Igor Ulitsky

Finally - the 🧵! So, the piRNA pathway defends the animal germline from transposons. But most of what we know comes from narrow developmental windows like late oogenesis, where it's easiest to study. We asked if the pathway is the same across development. It is not! /+

A pervasive RT–qPCR artifact inflates RNA knockdown by RNA-targeting CRISPR - Yikey Yikes! BTW, similar concerns apply to siRNAs/ASOs that are sometimes suspected to affect RT and/or PCR . So nice somebody looked into this! rdcu.be/RUYFaGa649va

We, the Weizmann Institute of Science community, deeply mourn the passing of Prof. Ada Yonath - Nobel Laureate and a Model of Scientific Perseverance. May her memory be a blessing. bit.ly/ada-yonath-eng

How do nuclear compartments form inside cell nuclei? We show RNA glues certain loci together to form a nuclear compartment. This involves special GC-rich regions of highly expressed genes that also associate with nuclear speckles, but interactions between these loci are independent of speckles!

Transcription stops. RNA splicing takes over 🧬 ✨ Our new preprint uncovers the post-transcriptional RNA splicing landscape powering mammalian oocyte development. Read it here 👇 www.biorxiv.org/content/10.6...

Excited to share our newest work! We asked whether RNA molecules need to be in a specific place in the cell to do their job. We found that a single RNA must reach the midbody, the structure that pinches two dividing cells apart, for cell division to finish efficiently. 🧵⬇️

Academic tweeps! How do your institutes implement support for scientists in the rapidly changing AI-era - i.e, who is training the students to use Claude Code, and making sure they don't wreckt the cluster? Does it work well? Tell here/DM + pls RT (heading a sub-committee...)

Transcription-dependent heterochromatin at the Xist promoter shapes the random choice of the inactive X chromosome https://www.biorxiv.org/content/10.64898/2026.07.22.737064v1

Woolfe et al, 2026. Decoding the mystery of ultra-conservation in developmental enhancers: a role for nucleosome positioning, DNA structure and transcription factor binding www.biorxiv.org/content/10.6... ▶️conserved non-coding elements ... favor nucleosome occupancy at their borders

Our paper out in Science today: The Metis defense system senses molecular byproducts released when a phage degrades the bacterial genome, and then prevents replication of the phage in the infected cell Congratulations @ostermanilya.bsky.social and co-authors!

Insulin synthesis is sustained by Tent5 poly(A) polymerases https://www.biorxiv.org/content/10.64898/2026.07.04.736497v1

Excited to share that our Metis story is now published in Science! 🎉 Bacteria can sense phage-induced degradation of their genome and activate immunity. Many thanks to everyone who contributed to this work. 📄 www.science.org/doi/10.1126/... More details in my earlier thread 🧵⬇️

Frank Grosveld has been a giant in the field of long-range gene regulation. Inspirational to me and I am sure for many others. Rest in peace.

a small attempt to capture this enormous loss and what Greg meant and means to so many. www.cell.com/cell/fulltex...

Sounds super interesting - hope we'll see more of these (lncRNAs linked by human genetics + mouse KOs to key phenotypes)! www.nature.com/articles/s41...

Amazing insight from David Brow @bmolchem.bsky.social on potential mechanisms of U6 snRNA dysfunction in retinitis pigmentosa! Plus a potential therapeutic strategy based on some classic nucleic acid biochemistry experiments and competing RNA structures. rnajournal.cshlp.org/content/earl...

Hey, wouldja look at that! An incredible one man show from Pablo Bora, an amazing postdoc...we used Steven Floor's beautiful REMORA approach (fusing RNA base editors to RBPs, allowing RBP cargo to be identified by edits) to explore RBP-RNA binding in mouse embryos doi: doi.org/10.64898/202...

🆕 review with @jpunfried.bsky.social out in Nature SMB. Direct roles of lncRNAs in transcriptional activation. What do we understand about how lncRNAs lure Pol2 and set the stage for RNA production, and what do we still miss? www.nature.com/articles/s41...

If you accept an invitation to review a manuscript and then decide not to do it, please be a decent person and notify the editor. Otherwise, you're part of the problem.

Can anyone recommend a tool for calling "transcribed regions" from chromatin/nascent RNA-seq data? (ideally, using annotated genes as a starting point)

I was in a coffee place and I don’t know who this person is who left their laptop to charge on a water fountain for over an hour unattended, but this person is the chillest person alive. I am sweating every time someone places something with liquid two meters away from my computer

I’m looking for an automated way to read others’s scientific data without giving credit or acknowledgement, and also claim full credit for insights from it. And I want it to have a fitting name OAI: say no more

Super excited that our two companion papers on saturation genome editing (SGE) of RNU4-2 and discovery of a novel recessive neurodevelopmental disorder (NDD) were published yesterday 🥳 SGE experiment: www.nature.com/articles/s41... Recessive NDD characterisation: www.nature.com/articles/s41... 🧵

We are excited to share our new paper in Molecular Cell uncovering how the viral lncRNA RNA2.7 reshapes host cell biology! sciencedirect.com/science/authShare/S1097276526001565/20260324T143400Z/1?md5=16c84051c2f253c4665427f837a529d3&dgcid=author A thread 🧵

As a kid, watching Walker, Texas Ranger taught me that many problems in life can be solved by a well-timed roundhouse kick, a lesson that has served me well in academia

Timely reminder that a few years ago we named the Norris1 lncRNA, which remains quite enigmatic, but, fittingly for Chuck, is expressed primarily in the testis pmc.ncbi.nlm.nih.gov/articles/PMC...

Human DHX29 detects nonoptimal codon usage to regulate mRNA stability | @science.org www.science.org/doi/10.1126/...

There has never been a better time to study functional and mechanistic biology at the organismal (!) level than now in the age of AlphaFold and CRISPR.

"This observation supports the error hypothesis and suggests that metazoan transcript diversity is largely deleterious." Love this since it matches my priors :-) dx.plos.org/10.1371/jour...

This line of business would make tons of $$$ in Israel this week

Out today: We discovered new viral proteins that target immune signaling molecules, solely based on their AlphaFold-predicted shapes www.science.org/doi/10.1126/... Congrats Nitzan Tal and coauthors! Thank you Kranzusch lab for the fun collaboration! Linking below previous thread on our findings

Don’t worry. Soon, everyone here will be an expert on air wars in the Middle East.

TFW you generously accepted review invitations thinking you'd have two ~18 hr flights TLV<->Cancun this week for reviewing, then war breaks out, but you still need to review these papers/grants

... and we're back to in-shelter selfies!

Our most recent work on the “function and evolution” of #nuclear-speckles is now online at Cell @cp-cell.bsky.social doi.org/10.1016/j.ce... Read the thread👇 for the highlights of our findings.

🤩💪 Out now! 3D regulatory hubs in sex determination With @mamartirenom.bsky.social & Capel labs, led by @imotagom.bsky.social & @jrotwitguez.bsky.social 1️⃣ METALoci – explore #3DGenome 🧬 2️⃣ Non-coding region controlling Fgf9 🧩 3️⃣ Meis genes = new key players 🌟 👉 rdcu.be/e5sm2 1/n Bluetorial 👇

Integrative multiomics analysis and CRISPR screening identify functional noncanonical translation loci in the mouse immune system. https://www.biorxiv.org/content/10.64898/2026.02.23.707583v1

So awesome!

This is a fascinating paper that reveals defined and clear mechanism for a phenomenon that for some seemed unbelievable- the up regulation of genes paralogous to those with specific types of inactivating mutations. This is called transcriptional adaptation 1/ www.science.org/doi/10.1126/...

Tread -1- EpiSci - I am very proud to share with you our new study that you can access on @biorxivpreprint.bsky.social (see link below) "The Interaction with Nanotopographical Environment regulates nuclear mechanoresponse in mESCs via Histone Demethylase KDM3A. www.biorxiv.org/content/10.6...