On July 1st, I'll be joining the faculty at UC Berkeley, with a joint appointment in the Division of Molecular Therapeutics within MCB and the Helen Wills Neuroscience Institute.

Astrocytes do so much more than any of us thought - they even communicate among specific brain regions across hemispheres! The journey to this paper spanned nearly a decade, but I'm most excited to see what everyone else does with the tools we've built. There's so much for all of us to explore!

New study led by Ning Shen w/ @phruzycki.bsky.social: a genome-wide in vivo CRISPR screen in a retinitis pigmentosa mouse model identifies genes whose loss accelerates photoreceptor death. Overexpressing two, UFD1 and UXT, preserves photoreceptors, retinal function, and vision. 🧵

Happy to say that I defended my PhD! Very excited to reach a goal I’ve been working towards for so many years. Looking forward to my next chapter in science! #PhDone #neuroskyence 🧠🧪

My lab at MSKCC in New York is hiring for two positions. Join us at the frontier of functional genomics, studying fibroblast state transitions, combinatorial genetics, and ECM in disease. Please share with anyone who might be a good fit! (Mustache not required.)

Our paper is (finally) out in Cell today! CRISPR screens in iPSC-derived neurons reveal principles of tau proteostasis www.cell.com/cell/fulltex... Great collaborative effort - read more from first author @asamelson.bsky.social below:

1/ Our new study, led by Jingwen Ding, examines the role of transcription factors during human neurogenesis to identify gene regulatory networks influencing cell fate, maturation, and subtype specification www.nature.com/articles/s41...

Arc bioinformatics scientists @noamteyssier.bsky.social and Alex Dobin have just released cyto, an ultra-high throughput processor specifically optimized for @10xgenomics.bsky.social Flex single-cell data. We are excited to make this resource open source: www.biorxiv.org/content/10.6...

Anyone know why astrocytes would be doing this weird stringy thing in the cerebellar peduncles (and a bit in the arbor vitae)? This reporter behaves well astrocyte-wise through the rest of the brain, but herein seems to fill long (astrocyte?) processes. Super strange. #neuroskyence 🧪

Career update: I'm happy to say that I've accepted a postdoc position at UC Berkeley at @innovativegenomics.bsky.social in Jennifer Doudna's lab! I'm looking forward to this exciting new chapter of my scientific career!

NREL’s public outreach programs were formative for developing my interest in science as a kid. I hope they’re able to continue their work leading the way in renewable energy technology development, despite an unfortunate name change…

I work with large collections of AnnDatas for single-cell work and got tired of opening notebooks for simple operations. Built a CLI tool to handle some common stuff directly from the terminal. Quick ops: downsample, concat, pseudobulk, QC, metadata export, etc. github.com/noamteyssier...

Who doesn't love a library? A pooled library, that is! Grab a hot drink and your reading glasses and enjoy browsing the libraries Addgene has to offer: https://twp.ai/4it3AO

The small conference room on my floor with a wonky door has claimed another victim

@sfn.org #SfN25 #SanDiego starts this Saturday. The lab is going to be there in full force - see our presentations below. Represented this year by @borderbiologist.bsky.social, Nick Kathman, @mrodea.bsky.social, @melcooperphd.bsky.social, @pryprk.bsky.social, @kerrylimberg.bsky.social. (1/2)

Our new manuscript, led by Emily Corrigan, examines inhibitory neuron diversity across approximately 160 million years of evolutionary divergence, as part of BRAIN Initiative Cell Atlas Network (BICAN) developing brain atlas package: www.nature.com/articles/s41...

Glia gang, this is for you! In this video by our #ElectronMicroscopy team, shows a pyramidal neuron (PyC) surrounded by 8 glia brain cells – 5 microglia (MG) and 3 oligodendrocyte progenitor cells (OPC). 🧠📈 http://microns-explorer.org

RIP Kit-Kat 💔

Excited to share our study out in @natcellbio.nature.com! Led by @mikelangelipid.bsky.social, we identify the first #LipidDroplet lipid quality control pathway: LD-localized FSP1 protects stored lipids from oxidative damage and prevents LD-initiated #ferroptosis. www.nature.com/articles/s41...

We've been doing some amazing stuff outside the astrocyte realm. Check out our latest Oligo investigation led by @pryprk.bsky.social !

uv makes installing and using Python *so* easy! It works on pretty much any computer and it's lightning fast. 🔭☄️ #astrocode If you're still using conda, pyenv, or... basically any other tool, then I can *highly* recommend switching:

Thank you Alzforum for featuring our new preprint identifying regulators of disease states of #microglia. Project led by Amanda McQuade, computation by Reet Mishra, collaboration with the Nunez and De Jager labs. Alzforum www.alzforum.org/news/researc... Preprint www.biorxiv.org/content/10.1...

Excited to share new work from the lab showing that FTD causing mutations in tau cause widespread defects in microglia function www.nature.com/articles/s41...

Just out in Nature! “The astrocytic ensemble acts as a multiday trace to stabilize memory.” We identified astrocytic ensembles that link experiences across days to stabilize memory nature.com/articles/s41.... New astrocyte tools are openly available at Addgene: addgene.org/Jun_Nagai/. 1/8

In the early years of my PhD I remember being asked if we'd ever treat or cure diseases like HIV or Huntington's. I remember saying maybe, but not knowing if I believed. Seeing research pay off as real impact on human lives is - incredible. www.bbc.com/news/article... www.bbc.com/news/article...

Wow now that was an earthquake! Never been shaken awake before

Rust 1.90.0 is out! blog.rust-lang.org/2025/09/18/R... Major features: * lld as the default linker on x86_64-unknown-linux-gnu * cargo workspace publishing support built into cargo * more const context APIs, and stabilization of new useful APIs

Wonderful to see our paper on the #organelle signatures of #neurons and #astrocytes out in final form - congratulations, Shannon Rhoads and team!🎉 t.co/BPxKlbU6Ou

Most neurodevelopmental disorders are caused by having 1 functional gene copy. Using SCN2A, we show that upregulating the functional copy rescues neuronal phenotypes. Amazing work with @neurobender.bsky.social led by Serena Tamura, Andrew Nelson, Perry Spratt & others. www.nature.com/articles/s41...

Microglia-astrocyte crosstalk regulates synapse remodeling via Wnt signaling @cellcellpress.bsky.social @travisfaust.bsky.social www.cell.com/cell/fulltex...

Biology Department xkcd.com/3140/

David Baltimore, Nobel-Winning Molecular Biologist, Dies at 87 www.nytimes.com/2025/09/07/s...

Getting a breathtaking view of the Golden Gate Bridge! Perfect conditions this weekend.

Thanks Nat Neuro for posting about our recent paper! This project goes to show that you can have a really wacky idea and occasionally biology will throw you a bone and it will actually work!

I love this cover art so much!

Astrocytes are connected by gap junctions in large, plastic networks that link brain regions not connected by neurons, a new preprint shows. By @callimcflurry.bsky.social #neuroskyence www.thetransmitter.org/astrocytes/a...

Ever wanted to do a CRISPR screen directly in the mammalian brain? While perturbing thousands of genes in parallel? All while targeting specific cell types? Check out our latest paper describing CrAAVe-seq, a powerful new functional genomics tool for massively parallel neuroscience research

This is an airyscan confocal movie of mitochondria (white) moving around in a mouse astrocyte. Actin filaments are in orange and microtubules are in blue.

Cool astrocyte paper!

Good grief, the US National Cancer Institute projects it will fund only one in 25 RO1 grant applications in 2026. This is massively defunding cancer research. Despicable vandalism. www.cancer.gov/grants-train...

Tenure-track faculty search of the UCSF Biochemistry & Biophysics Department is open for applications! We are looking for creative, innovative scientists asking fundamental questions in any area of biology. Join our vibrant, collaborative, and supportive community! aprecruit.ucsf.edu/JPF05702

Astrocytes connect specific brain regions through plastic gap junctional networks https://www.biorxiv.org/content/10.1101/2025.07.18.665573v1

Pooled #CRISPR screens are a staple of functional genomics in mammalian cells. Yet somehow in the best genetic model™ no equivalent system was available. Until now! The @perrimonlab.bsky.social lab now presents efficient pooled CRISPR screening in #Drosophila cells. www.nature.com/articles/s41...

Still the ggoat

Today I learned that ultracentrifuge rotors expire?? And need to be repurchased periodically? These things still feel brand new and should last decades...

At times like these it's important to remember the 3 branches of science

Online now:

www.alz.org/news/2025/ke...

"to run a contest that you end up not funding as a private organization at this time is… both extremely wasteful of these people’s time, and just devastating in terms of morale." I spoke with @aniloza.bsky.social at STAT today about HHMI's decision not to fund this round of Hanna Gray applicants.

The mutation responsible for orange coloration in domestic cats has been identified! This effect in ARHGAP36, an X-linked gene, explains why male cats are more likely to be orange. 🧪 www.cell.com/current-biol...