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Jackson Hoffman

@jxhoffman.bsky.social

1K followers 673 following 118 posts

Scientist in North Carolina studying chromatin remodelers and transcription factors. @fnucleosome.bsky.social coorganizer ORCID: 0000-0002-6256-144X Views and posts are all my own

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Jackson Hoffman @jxhoffman.bsky.social · 23/07/2025

Here's your (fluid) ounce, and just one tube is a tablespoon!

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Jackson Hoffman @jxhoffman.bsky.social · 21/07/2025

I think this organoid is upset with me 😠

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Jackson Hoffman @jxhoffman.bsky.social · 07/07/2025

Cool work from Sarah Bray's lab at Cambridge looking at Notch-induced transcription hubs: www.biorxiv.org/content/10.1... from Fig 5: hubs are stabilized/strengthened when initiation is inhibited and diminished when P300 is inhibited.

part of figure 5 from the linked preprint. shows 3d plot of fluorescent data where strong signal looks like dark mountains rising above a gray floor.

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Jackson Hoffman @jxhoffman.bsky.social · 13/06/2025

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Jackson Hoffman @jxhoffman.bsky.social · 15/01/2025

Hey NC/Triangle area folks: registration is now open for the annual Chromatin and Epigenetics Symposium at UNC on March 6th! This year's program will feature a keynote talk from Cigall Kadoch and short talks selected from abstracts. Click to register: unclineberger.org/event/2025-c...

DNA to chromatin cartoon to advertise the Chromatin and Epigenetics Symposium

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Jackson Hoffman @jxhoffman.bsky.social · 17/12/2024

Choose 20 books that have stayed with you or influenced you. No explanations, no reviews, just covers. #Books #BookSky #BookChallenge Days 7+8 The Master and Margarita - Mikhail Bulgakov The Satanic Verses - Salman Rushdie

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Jackson Hoffman @jxhoffman.bsky.social · 13/12/2024

Choose 20 books that have stayed with you or influenced you. No explanations, no reviews, just covers. #Books #BookSky #BookChallenge Day 5+6 A memory called empire - Arkady Martine A desolation called peace - Arkady Martine

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Jackson Hoffman @jxhoffman.bsky.social · 12/12/2024

Choose 20 books that have stayed with you or influenced you. No explanations, no reviews, just covers. #Books #BookSky #BookChallenge Day 4 The New Wilderness - Diane Cook

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Jackson Hoffman @jxhoffman.bsky.social · 10/12/2024

Choose 20 books that have stayed with you or influenced you. One book per day for 20 days, in no particular order. No explanations, no reviews, just covers. #Books #BookSky #BookChallenge Day 3 Children of Memory - Adrian Tchaikovsky

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Jackson Hoffman @jxhoffman.bsky.social · 09/12/2024

Day 2 Slow River by Nicola Griffith

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Jackson Hoffman @jxhoffman.bsky.social · 08/12/2024

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Jackson Hoffman @jxhoffman.bsky.social · 15/11/2024

Finally, we tested the HAT/HDAC role in this. TSA treatment blocked/masked the increase in acetylation whereas p300 inhibition didn't prevent the triptolide effect. Thus, we propose that HDAC activity at TSSs is coordinated by RNAP2 and txn initiation

A) Western blots of whole cell lysates from A1-2 cells treated +/-triptolide, A485, and TSA. B-D) Meta-profiles of Cut&Tag signal in A1-2 cells treated +/-triptolide, A485, and TSA.

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Jackson Hoffman @jxhoffman.bsky.social · 15/11/2024

Blocking pause release with Flavopiridol did not trigger the same increase in acetylation, suggesting that loss of RNAP2 and initiation were the critical steps here. Indeed, using a HCT116-AID-RPB1 cells to degrade RNAP2 yielded similar results as triptolide

A-D) Meta-profiles of ChIP-seq and Cut&Tag signal +/-2 hours flavopiridol over active TSSs. E) Western blots of whole cell lysate from HCT116-mAID-POLR2A cells +/-Auxin or triptolide. F-H) Heatmaps depicting relative change ((auxin – control) / max(control)) in Cut&Tag signal for indicated marks.

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Jackson Hoffman @jxhoffman.bsky.social · 15/11/2024

Not just K27ac. Every acetyl mark we checked was increased at active TSSs. H2AZ was also increased at TSSs, but H3K4me3 and ATAC accessibility are unchanged This was all done in T47D A12 breast cancer cells, so we then confirmed these patterns of K27ac, K4me3, and H2AZ in 7 additional cell lines

A-J) Meta-profiles of representative Cut&Tag replicates +/-2 hours triptolide over active TSSs. K-M) Heatmaps depicting relative change ((Triptolide – control) / max(control)) in Cut&Tag signal over Refseq TSSs in indicated cell lines.

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Jackson Hoffman @jxhoffman.bsky.social · 15/11/2024

We used triptolide to test whether transcription was required for hormone-induced histone acetylation. It was not... in fact, acetylation was increased following inhibition of initiation

A) Differential heatmap of K27ac ChIP-seq signal (log2 Dex/Veh) over Class III GR peaks +/-2 hours triptolide. B) Browser image of K27ac ChIP-seq and RNAP2 ChIP-seq over ZBTB16 gene. C) Browser image of K27ac ChIP-seq and RNAP2 ChIP-seq over GLUL gene. D) Western blot of whole cell lysates from 4 biological replicates each of A1-2 cells +/-2 hours triptolide. E) Meta-profiles of representative ChIP-seq and Cut&Tag replicates over Refseq TSSs. F) Meta-profiles of representative RNAP2 ChIP-seq +/-2 hours triptolide over Start-seq defined active, inactive, and enhancer TSSs. G) Meta-profiles of representative K27ac Cut&Tag +/-2 hours triptolide over Start-seq defined active, inactive, and enhancer TSSs.

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