Sign in

sharon greenblum

@greensi.bsky.social
232 followers 129 following 19 posts

comp bio research scientist @jgi @lbnl

PostsRepliesMedia
Reposted by sharon greenblum
Ronan @omalley-regulome.bsky.social · 10/02/2026
New preprint! The same TFs can drive distinct regulatory programs depending on where they bind.
 TSS → rapid stress responses
 Intronic & upstream → cell-type programs
 Enhancer-like CRMs → embryo/meristem programs
 Coding-sequence binding → repression www.biorxiv.org/content/10.6...
0197
sharon greenblum @greensi.bsky.social · 07/02/2026
our new preprint is out! if a transcription factor binds near a gene, does it matter exactly where? keep an eye out for a 🧵soon!
041
Reposted by sharon greenblum
Axel Visel @axelvisel.bsky.social · 22/09/2025
Sequencing methods 🧬 have come a long way from census counts 🔢 to assembling genomes and understanding the functions 🧪 of bacteria and viruses. New review by @jgi.doe.gov's Gitta Szabó, @emileyeloe-fadrosh.bsky.social, Tanja Woyke with @jeffinerca.bsky.social www.nature.com/articles/s41...
nature.com
A genomic view of Earth’s biomes - Nature Reviews Genetics
Genome-wide approaches have uncovered the vast microbial and viral diversity across ecosystems. This Review explores advances in metagenomics, single-cell sequencing and functional profiling to elucid...
0168
Reposted by sharon greenblum
Marianna Karageorgi @mkarag.bsky.social · 15/09/2025
How do populations maintain an evolutionary memory? I am happy to share that our work with Dmitri Petrov @petrovadmitri.bsky.social, Paul Schmidt, and colleagues on dominance reversal and stabilization of insecticide resistance in changing environments over time is now published at Nature EE.
nature.com
Beneficial reversal of dominance maintains a large-effect resistance polymorphism under fluctuating insecticide selection - Nature Ecology & Evolution
Measuring selection and dominance in fitness of the insecticide-resistant Ace alleles in Drosophila melanogaster, the authors show evidence for beneficial reversal of dominance, a mechanism that can s...
35419
Reposted by sharon greenblum
Joint Genome Institute @jgi.doe.gov · 26/08/2025
Do YOU use data from across multiple sources? (See list in link below) We want to know: ✅HOW you gather comprehensive data for the same sample; ✅WHERE you look; and ✅WHAT OBSTACLES you face Sign up by 8/31 to share: jointgeno.me/UserResearch2025 @berkeleylab.lbl.gov @nigelmouncey.bsky.social
jointgeno.me
034
Reposted by sharon greenblum
Axel Visel @axelvisel.bsky.social · 21/08/2025
Postdoc opportunity with @tomasbruna.bsky.social here at @jgi.doe.gov @berkeleylab.lbl.gov: Develop, benchmark, and apply Plant Genomic Language Models (gLMs) 🌿🧬💻 jobs.lbl.gov/jobs/computa... #AI #PlantGenomics #gLMs #Postdoc
Graphic announcing a Computational Postdoctoral Fellow position.  Text: Computational Postdoctoral Fellow – Plant Genomic Language Models (gLMs). JGI is seeking a Computational Postdoctoral Fellow to join a funded project at Berkeley Lab’s Joint Genome Institute applying genomic language models (gLMs) to unlock new biological insights in plants. Join one of the world’s leading genomics facilities to pioneer AI applications in plant biology, with access to cutting-edge computational resources and diverse genomic datasets. This project will focus on developing and exploring applications of gLMs to plant genomes, from identifying novel regulatory elements to revealing evolutionary patterns across species, with particular interest in cross-species and data-limited scenarios. In this role, you will design tasks and datasets to test and extend gLM capabilities, apply models to generate new biological hypotheses, and share findings through high-impact publications and presentations.
11520
sharon greenblum @greensi.bsky.social · 20/08/2025
these are all real DAP-seq peaks! specifically, peaks in the promoter of SWEET11 (a sugar transport gene) and its orthologs across 10 plant species the darker colored peaks are binding sites for transcription factors that have maintained regulation of SWEET11 across 100+M years of plant evolution
1152
Reposted by sharon greenblum
Axel Visel @axelvisel.bsky.social · 20/08/2025
If you are interested in using DAPseq for your plant, algal, fungal or microbial genomes, consider applying to one of @jgi.doe.gov's user programs: jgi.doe.gov/work-with-us...
jgi.doe.gov
User Programs | Joint Genome Institute
Learn more about our Community Science Program, as well as other collaborative opportunities available through the FICUS call and other special initiatives.
042
sharon greenblum @greensi.bsky.social · 20/08/2025
Final note - all of this data is publicly available! See our GEO ‘superseries’ page here: ​​https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE299028 and please reach out if you have questions or trouble finding anything. We’re excited to see what you uncover!
030
sharon greenblum @greensi.bsky.social · 20/08/2025
This project was a huge team effort with five(!) co-first authors, including JGI scientists @leobaumgart.bsky.social, @abmora.bsky.social, Peng Wang, and Yu Zhang each playing crucial roles, and @omalley-regulome.bsky.social at the helm. An amazing group!
131
Reposted by sharon greenblum
Peter Sudmant @psudmant.bsky.social · 13/08/2025
The Sudmant lab at UC Berkeley is seeking a postdoc to work on a fully funded NIH project to understand differences in DNA repair and somatic mutation across the primate tree of life. Please spread widely to those who may be interested aprecruit.berkeley.edu/JPF05052
aprecruit.berkeley.edu
Postdoctoral Scholar – Genomics, Aging, Somatic Mutation, Structural Variation, Evolution , Cancer – Integrative Biology
University of California, Berkeley is hiring. Apply now!
15655
sharon greenblum @greensi.bsky.social · 20/08/2025
And on a practical level, tracking TF activity instead of expression of individual genes gives us quantitative big-picture way to compare cell types within a species, as well as across both closely and distantly related lineages.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
Take-home! DAP-seq + snRNA-seq 🤜 🤛 Integrating these data types with the framework of comparative genomics is an incredibly powerful way to understand gene regulation, giving us a window into why genes are expressed where they are, and how TF regulons get rewired to enable novelty.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
But we also found cases where TFs became active in new cell types, and added hundreds of new target genes along the way. We even found a cool example of evolution in action, where the balance of regulatory power seems to be switching between MYB and NAC TFs in xylem.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
First - we saw that plenty does stay the same. We could often recognize a sorghum cell type as the best match to a brassica cell type simply by looking at its TF activity profile.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
But we weren’t done yet! Not all functional binding sites are conserved forever, right? Otherwise how do we get novelty? We next jumped across the tree to the bioenergy grass Sorghum and used the same approach to track TF activity, this time with binding sites conserved in its grass relative, rice.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
Many TF-celltype relationships reflect long-standing functional knowledge. For example, MYB107 target genes lit up suberized-endodermis, aligning with the TF's known role in suberin synthesis. Others were entirely new. This opens doors for creative ways to describe and even manipulate cell types.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
We now had a robust and powerful framework for tracking TF activity. Focusing only on expression of target genes with conserved binding sites, we could infer where each TF was active. Mapping out the active TFs in each cell type gave us the big-picture view of gene expression we’d been waiting for.
110
sharon greenblum @greensi.bsky.social · 20/08/2025
Sure enough, the most conserved binding sites showed the highest correlation between TF and target gene expression, and marked genes with the most cell type-specific expression patterns in all 4 species. Makes for a strong case that conservation is a good marker of binding site importance.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
So next we generated snRNA-seq atlases for 3 different tissues (seedling, leaf, and flower) of each of the 4 Brassica species. Again, lots of data. But again, multiplexing helps! We found that extracting and profiling nuclei from all species together made for an easier protocol and cleaner data.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
Binding sites shared across all 4 species had all the hallmarks of being ‘functional’ - they had lower within-species nucleotide diversity, higher chromatin accessibility, and were near functionally-related genes. But to be sure they impact expression - maybe we should look at expression data?
110
sharon greenblum @greensi.bsky.social · 20/08/2025
We tested this theory with 4 related species from the Brassica family. For every TF binding site in A. thaliana, we asked how many of the other species had a binding site for the same TF near an orthologous gene.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
Second challenge: while DAP-seq finds all possible binding sites, not all actually impact expression of a nearby gene. Which binding sites matter? For that we turned to comparative genomics. We reasoned that binding sites that stuck around during evolution are probably there for a reason.
100
sharon greenblum @greensi.bsky.social · 20/08/2025
If that sounds like a lot of data - it is. The first challenge was profiling all those TF binding sites - our team previously developed multiDAP-seq (www.nature.com/articles/s41...), which applies the in vitro DAP-seq method to a pool of genomes. Here we optimized it for bigger eukaryotic genomes.
nature.com
Persistence and plasticity in bacterial gene regulation - Nature Methods
This work presents biotin-DNA affinity purification (DAP) sequencing, that is, an in vitro, clone-free workflow to profile transcription factor (TF) DNA binding, as well as multiDAP to simultaneously ...
110
sharon greenblum @greensi.bsky.social · 20/08/2025
Single-nuclei RNAseq reveals which genes are ‘on’ where, but behind the scenes it’s transcription factors directing the show. Here, we profiled binding of 100s of TFs in 10 plant genomes, plus a suite of new snRNA atlases - to ask: does tracking TF activity help simplify and compare snRNA data?
110
sharon greenblum @greensi.bsky.social · 20/08/2025
August’s Nature Plants cover story shows how we integrated large-scale multiDAP and snRNA data to reveal drivers of cell type identity and evolution in flowering plants. www.nature.com/nplants/volu... We packed a lot into this paper! Here’s a single-cell spin on what we found:
nature.com
Nature Plants - Cistromes uncovered
Transcription factors (TFs) have specific patterns of binding to gene promoter regions, which have similarities and differences within TF families and...
3319
Reposted by sharon greenblum
Ben Good @benjaminhgood.bsky.social · 16/08/2025
Excited to share a new preprint w/ the Sonnenberg lab, led by Matt Carter, @zzzhiru.bsky.social & @mattolm.bsky.social. We analyzed the microbiomes of two non-industrialized populations from opposite sides of the globe to try to reconstruct the recent evolutionary history of our gut microbiota.
biorxiv.org
Prehistoric Global Migration of Vanishing Gut Microbes With Humans
The gut microbiome is crucial for health and greatly affected by lifestyle. Many microbes common in non-industrialized populations are disappearing or extinct in industrialized populations. Understand...
26521
Reposted by sharon greenblum
Nandita Garud @nanditagarud.bsky.social · 22/07/2025
I am seeking a postdoc for my group at UCLA. We work at the intersection of population genetics x microbiome (garud.eeb.ucla.edu). If interested, please message me!
garud.eeb.ucla.edu
Garud Lab
18598
Reposted by sharon greenblum
Marianna Karageorgi @mkarag.bsky.social · 22/01/2025
How is functional variation at large-effect loci maintained in natural populations? Thrilled to share our work showing how beneficial dominance reversal helps fruit flies maintain a resistance polymorphism as selection varies in their environment! A thread 🧵 1/n www.biorxiv.org/content/10.1...
biorxiv.org
Dominance reversal maintains large-effect resistance polymorphism in temporally varying environments
A central challenge in evolutionary biology is to uncover mechanisms maintaining functional genetic variation1. Theory suggests that dominance reversal, whereby alleles subject to fluctuating selectio...
13621
Reposted by sharon greenblum
Berkeley Lab @berkeleylab.lbl.gov · 02/12/2024
The Dark Energy Spectroscopic Instrument (DESI) scientists mapped how nearly 6 million galaxies cluster across 11 billion years of cosmic history. Their observations line up with what Einstein's theory of general relativity predicts. 🧪 newscenter.lbl.gov/2024/11/19/n...
411118
Reposted by sharon greenblum
Katherine Xue @ksxue.bsky.social · 19/11/2024
Hi friends new and old! I study how microbes interact and evolve in complex communities like the human gut microbiome.🦠🧬💩 I'm thrilled to share that I'm starting a lab at UC Irvine in April 2025 and am recruiting at all levels - please spread the word! kxuelab.com More about my work below...🧵1/n
kxuelab.com
Xue lab at UC Irvine
Ecology and evolution in the human gut microbiome
24390115