ICYMI: New online: Cryo-EM structure, enzymatic activity and genome targeting of canonical PRC1

Cryo-EM structure, enzymatic activity and genome targeting of canonical PRC1

Nature Structural & Molecular Biology, Published online: 14 September 2026; doi:10.1038/s41594-026-01885-6Ciapponi et al. determine the cryo-electron microscopy structure of the canonical Polycomb repressive complex 1 holocomplex and show how its architecture coordinates complex assembly, H2A monoubiquitination and genomic targeting.

dlvr.it

Bluetorial-Jim Watson I met Jim Watson a few times but did not know him well. However, I was greatly influenced by his book “The Double Helix”. He was a complicated human being with some very, very bad features, but some good contributions. What follows is my personal perspective. 1/41

a cartoon says hey everybody an old man 's talking while bart simpson looks on

ALT: a cartoon says hey everybody an old man 's talking while bart simpson looks on

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Our latest paper has just been published in Cell! doi.org/10.1016/j.ce... We developed a new method called MCC ultra, which allows 3D chromatin structure to be visualised with a 1 base pair pixel size.

1/ 🚀 AEBP2 isn’t what we thought. You were told that AEBP2 promotes PRC2 activity on chromatin. We found the opposite: the most prevalent AEBP2 isoform inhibits PRC2 activity. 👉 surl.li/cgwqcq A thread 🧵

🧵1/Exciting news in cancer epigenetics! Our latest research, "AEBP2-Directed H3K27me2 Defines a Specific Vulnerability in EZH2-mutant Lymphoma", is now available on www.biorxiv.org/content/10.1.... Here's a thread summarizing our findings!👇 #CancerResearch #Epigenetics #Chromatin #Lymphoma

AEBP2-Directed H3K27me2 Defines a Specific Vulnerability in EZH2-mutant Lymphoma

The catalytic subunit of Polycomb Repressive Complex 2 (PRC2), EZH2, is recurrently mutated in 25% of diffuse large B-cell lymphomas (DLBCL), causing increased H3K27me3 and decreased H3K27me2 levels. ...

biorxiv.org

Check it out, Chromatin Kids! Chromatin remodeller does stuff to Transcription Factors! Functions where it is seldom seen! Both decreases and increases chromatin accessibility! How cool is that?

bioRxiv Molecular Biology@biorxiv-molbio.bsky.social · last yr.

The chromatin remodeller CHD4 controls both nucleosome integrity and transcription factor binding to promote activity of active regulatory elements and to prevent activation of silent enhancers https://www.biorxiv.org/content/10.1101/2025.08.29.672645v1

Excited to share a new preprint from the lab! This (doi.org/10.1101/2025...) and an earlier one (doi.org/10.1101/2025...) mark my lab's first steps into studying how Polycomb modifications get established in early Drosophila development. 🧵 1/10

bioRxiv Developmental Biology@biorxiv-devbio.bsky.social · last yr.

Lower-order methylation states underlie the maintenance and re-establishment of Polycomb modifications in Drosophila embryogenesis https://www.biorxiv.org/content/10.1101/2025.07.25.666882v1

We are excited to share our new preprint demonstrating that nucleic acid interactions with SUZ12 constrain PRC2 activity, establishing a kinetic buffer essential for targeted gene silencing and revealing vulnerabilities in diffuse midline gliomas. www.biorxiv.org/content/10.1...

Another paper bluetorial! Today: how does the spatial location of genes influence their function? (1/n) www.nature.com/articles/s41...

The nuclear periphery confers repression on H3K9me2-marked genes and transposons to shape cell fate - Nature Cell Biology

Marin et al. report the role of lamin proteins and the lamin B receptor (LBR) in chromatin positioning at the nuclear periphery. Knockout of all lamins and LBR in mouse embryonic stem cells leads to h...

nature.com

[0/8] Stoked to share our work with @arjunraj.bsky.social on tissue organization in the gastruloid. We use lineage tracing and spatial transcriptomics to show that diversity among stem cell clones promotes, rather than hinders, gastruloid development: www.biorxiv.org/content/10.1...

Gastruloid patterning reflects division of labor among biased stem cell clones

Embryonic development typically requires precise coordination among cells to achieve reproducible outcomes, leading to the assumption that cellular heterogeneity must be minimized or buffered against....

biorxiv.org

Online Now: CRAMP1 drives linker histone expression to enable Polycomb repression Online now:

CRAMP1 drives linker histone expression to enable Polycomb repression

Challenging the prevailing view that H1 linker histones represent a general feature of repressed chromatin, Matthews et al. show a specific requirement for H1 in epigenetic repression by PRC2. Ablation of the H1 activator CRAMP1 results in linker histone insufficiency and derepression of PRC2 target genes.

dlvr.it

New from our lab & @harrisonflylab.bsky.social: Drosophila models of H3 K27M & EZHIP reveal conserved chromatin regulators that buffer PRC2 inhibition. An in vivo screen highlights how developmental defects can be rescued despite global H3K27me3 loss. doi.org/10.1101/2025...

I'm genuinely sorry that Fetterman had a stroke and suffers from depression. But arguing that he has a free pass not to do his job in the name of destigmatizing brain injury and mental health struggles is offensive. If he can't do it, he should resign. If he doesn't want to, he should resign faster.

Mark Harris@markharris.bsky.social · last yr.

In which John Fetterman argues with inflamed self-righteousness that he's being bullied into doing parts of the job that he thinks are dumb. Like...showing up to vote. And serving on Senatorial committees. And meeting with constituents. www.nytimes.com/2025/05/24/u...

Online Now: A specific form of cPRC1 containing CBX4 is co-opted to mediate oncogenic gene repression in diffuse midline glioma Online now:

I shared the story of Natalie, a mom from WA state with stage 4 colorectal cancer enrolled in an NIH clinical trial, but she was told her care was delayed because of RFK Jr.'s staffing cuts. He admitted NIH cuts, "are gonna hurt."   It's unacceptable. I'm demanding accountability.

"NIH Cuts Will Hurt" RFK Jr. Admits When Pressed by Senator Murray on Harm to NIH Clinical Care

YouTube video by Senator Patty Murray

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This cure for sickle cell anemia was made possible by NIH-funded research to turn the gene for fetal hemoglobin back on. It was done predominantly by NIH researchers, including intramural researchers on the NIH campus. irp.nih.gov/catalyst/33/...

Yours in negritude, Ryan K. Smith@mewefree.bsky.social · 2y ago

Looks like we've got a cure for sickle cell. www.cbsnews.com/newyork/news...

1/ H3K27me3 mimicry has repeatedly emerged through evolution, but what's the physiological relevance? We show that JARID2 and PALI1 mimic H3K27me3 to antagonise PRC2 in vivo and restrict the spread of Polycomb domains. 🧵 www.biorxiv.org/content/10.1...

PRC1 and PRC2 proximal interactome in mouse embryonic stem cells

PRC1 and PRC2 proximal interactome in mouse embryonic stem cells

Zijlmans and Stelloo et al. profiled in vivo proximal interactomes of PRC1 and PRC2 in mouse embryonic stem cells, identifying >100 proteins, including transcription factors and RNA-binding proteins. Their findings reveal shared and distinct roles of…

dlvr.it

Why does National Institutes of Health funding matter? It’s the fuel to find cures for: - Cancer - Alzheimer’s - Cystic Fibrosis - Pediatric Cancer - ALS - MS - Parkinson’s Trump tried to cut it, but thanks to AG Campbell, a judge blocked the cuts. This is why we fight.

Online now: Online Now: EZH1/EZH2 inhibition enhances adoptive T cell immunotherapy against multiple cancer models

EZH1/EZH2 inhibition enhances adoptive T cell immunotherapy against multiple cancer models

Porazzi et al. highlight how inhibiting the epigenetic regulators EZH2 and EZH1 enhances cancer cell immunogenicity, boosting the effectiveness of CAR- and TCR-engineered T cells across liquid and solid tumor models, which represents a promising strategy…

dlvr.it

𝐇𝐨𝐰 𝐝𝐨 𝐜𝐞𝐥𝐥𝐬 𝐫𝐞𝐦𝐞𝐦𝐛𝐞𝐫 𝐰𝐡𝐨 𝐭𝐡𝐞𝐲 𝐚𝐫𝐞 𝐚𝐟𝐭𝐞𝐫 𝐃𝐍𝐀 𝐫𝐞𝐩𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧? Our new study “Disabling leading and lagging strand histone transmission results in parental histones loss and reduced cell plasticity and viability” is out in 𝘚𝘤𝘪𝘦𝘯𝘤𝘦 𝘈𝘥𝘷𝘢𝘯𝘤𝘦𝘴. Led by @lleonie.bsky.social @biranalva.bsky.social 🧵 More below👇

Disabling leading and lagging strand histone transmission results in parental histones loss and reduced cell plasticity and viability

Losing parental histones during DNA replication fork passage challenges differentiation competence and cell viability.

tinyurl.com

Trump & Musk are making massive cuts to the National Institutes of Health. I know there is a lot going on right now, but this is one of worst things they have done so far, will affect cancer research and trials, the search for cures, innovation and competitiveness, our universities. Your lives.

Scientific advancements aside, this is economically irresponsible Every $1 spent by NIH generates $2.46 For example, in 2023, $47B in NIH spending generated ~$93B Halting NIH spending will LOSE the US a lot of money (and talent)

Adam Rogers@jetjocko.bsky.social · 2y ago

They…turned off…National Institutes of Health grants? That’s nearly $50 billion of scientific research.

Please see 🧵by @evhealy.bsky.social about our new paper exploring the role of PRC1 and PRC2 in non-dividing cells 👇

Evan Healy@evhealy.bsky.social · 2y ago

🧵 1/ We’re excited to share that our new paper with @adrianbracken.bsky.social lab is out 🎉 In this study (which began over 10 years ago!), we explore the biology of PRC2 and PRC1 in non-dividing cells. We also explore the effects of PRC2 inhibitor drugs on these cells. Here’s what we found👇

Work led by graduate student @trinitycookis.bsky.social and coauthors Alexandria Lydecker, @paulsauer.bsky.social, and @kasinath-lab.bsky.social is out today where we looked at the inhibition of PRC2 by histone PTMs associated with regions of active transcription. www.nature.com/articles/s41...

Structural basis for the inhibition of PRC2 by active transcription histone posttranslational modifications - Nature Structural & Molecular Biology

Structures reveal that histone H3K36me3 and H3K4me3 modifications reduce Polycomb repressive complex 2 (PRC2) function through the inhibition of histone tail engagement and antagonistic binding to the...

nature.com

1/n Some time ago my colleague, excellent cook, and friend Ivan told me: "Cacio e pepe is the recipe that I screw up more often. Let's make a project studying systematically the physics of that sauce". Prepare to get cheesy, I'm glad to share the Cacio e paper preprint: arxiv.org/abs/2501.00536

In news that surprises no scientist in cancer research, alcohol is linked to several cancers. Alcohol has one of the strongest links to increased cancer risk of any modifiable risk factors. I wrote about cancer basics here, including modifiable risk factors: news.immunologic.org/p/cancer-hun...

Cancer: hundreds of complex diseases that are plagued with misinformation

Lack of understanding of cancer underlies harmful pseudoscience that circulates rampantly

news.immunologic.org

Sadly, it’s a good time to once again share this amazing infographic that we ran at @science.org more than 7 years ago 🧪 #IDsky www.science.org/content/arti...

Here's the visual proof of why vaccines do more good than harm

See year by year how vaccines beat back nine dangerous infectious diseases

science.org