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Mark Pownall

@mpownall.bsky.social

https://pownall-lab.org | Sandler Fellow at UCSF | chromatin, transcription, microscopy (ChromExM), development πŸŸπŸ§¬πŸ”¬

512 Followers  |  141 Following  |  2 Posts  |  Joined: 26.10.2023  |  1.5552

Latest posts by mpownall.bsky.social on Bluesky

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Our Mini Review went online last night in Current Opinion in Genetics & Development
"Block copolymer concepts of how transcription organizes the stem cell genome"
doi.org/10.1016/j.gd...

Fig. 1: Stem cell–typical organization of the genome and transcription, and the block copolymer sorting concept.

15.01.2026 08:04 β€” πŸ‘ 22    πŸ” 10    πŸ’¬ 3    πŸ“Œ 1
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Multiscale structure of chromatin condensates explains phase separation and material properties The structure and interaction networks of molecules within biomolecular condensates are poorly understood. Using cryo–electron tomography and molecular dynamics simulations, we elucidated the structur...

@science.org πŸ§¬πŸ”¬ Multiscale structure of #chromatin condensates explains phase separation and material properties | Science www.science.org/doi/10.1126/... @janhuemar.bsky.social et al.

05.12.2025 05:24 β€” πŸ‘ 92    πŸ” 32    πŸ’¬ 2    πŸ“Œ 2

Here is a copy of last year's Twitter thread explaining our preprint - jump to (21) for the new stuff πŸ‘€

Synergy between cis-regulatory elements can render cohesin dispensable for distal enhancer function

now revised and journal accepted at www.science.org/doi/10.1126/...

πŸ§΅πŸ‘‡

27.11.2025 21:58 β€” πŸ‘ 89    πŸ” 45    πŸ’¬ 4    πŸ“Œ 3
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NIPBL dosage shapes genome folding by tuning the rate of cohesin loop extrusion Cohesin loop extrusion is a major driver of chromosome folding, but how its dynamics are controlled to shape the genome remains elusive. Here we disentangle the contributions of the cohesin cofactors ...

New preprint with @gfudenberg.bsky.social

We find the rate of cohesin loop extrusion in cells is set by NIPBL dosage and tunes many aspects of chromosome folding.

This provides a molecular basis for NIPBL haploinsufficiency in humans. πŸ§΅πŸ‘‡

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

16.08.2025 03:03 β€” πŸ‘ 114    πŸ” 53    πŸ’¬ 1    πŸ“Œ 6
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Our first expansion microscopy results. Imaged today on "normal" Zeiss LSM 900, revealing chromatin and RNA polymerase II clusters at an unreal level of detail.

Our PhD student @mofrawe.bsky.social learned the protocol from amazing @mpownall.bsky.social πŸ™

Months of preparation are paying off now!

14.08.2025 18:28 β€” πŸ‘ 80    πŸ” 8    πŸ’¬ 3    πŸ“Œ 1

Looking good!!

15.08.2025 12:03 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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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...

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

22.07.2025 17:10 β€” πŸ‘ 127    πŸ” 53    πŸ’¬ 11    πŸ“Œ 3
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Catalytic-dependent and independent functions of the histone acetyltransferase CBP promote pioneer-factor-mediated zygotic genome activation Marsh, Pirogov, et al. use the early Drosophila embryo to demonstrate that the conserved histone acetyltransferase CBP is required for pioneer-factor-mediated transcriptional activation of the zygotic...

Excited to share our new paper in @cp-molcell.bsky.social Molecular Cell: "Catalytic-dependent and independent functions of the histone acetyltransferase CBP promote pioneer-factor-mediated zygotic genome activation" β€” the big part of my PhD! www.cell.com/molecular-ce...

30.05.2025 12:51 β€” πŸ‘ 20    πŸ” 10    πŸ’¬ 2    πŸ“Œ 0
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Microscopy methods for the in vivo study of nanoscale nuclear organization Eukaryotic genomes are highly compacted within the nucleus and organized into complex 3D structures across various genomic and physical scales. Organization within the nucleus plays a key role in gene...

First paper from the Pownall lab calls for a first post on bluesky! Check out our mini review on nanoscale imaging of the nucleus in vivo. We are excited to address some of these open questions and technical challenges through future work from the labβ€”stay tuned!
portlandpress.com/biochemsoctr...

04.02.2025 00:25 β€” πŸ‘ 7    πŸ” 2    πŸ’¬ 0    πŸ“Œ 1

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