Ezequiel A. Galpern

Ezequiel A. Galpern

@eag91.bsky.social

‪MSCA fellow at @crg.eu‬ w/M. Dias and @jonnyfrazer.bsky.social > Biological Physics | Proteins | Comp Bio | ML | Health Genomics https://scholar.google.com/citations?user=n55NtEsAAAAJ&hl=en

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📊 Bigger is not necessarily better. Across ProteinGym benchmarks, scaling protein language models does not consistently improve zero-shot fitness prediction. We discuss why model likelihood is not the same as fitness, and what may be limiting performance.

Inverse-folding models have their own limitations: they can read functional conservation as a stability constraint. That matters when trying to disentangle folding from function. 🔧 We review these challenges and the emerging strategies to mitigate them.

2/2 🧬 Proteins need to fold, but they also need to function, and these requirements do not always agree. ⚖️ We review experimental and computational approaches that disentangle evolutionary constraints from folding stability, including our dark energy framework.

Ezequiel A. Galpern reposted

4/ We then combine the resulting folding-energy estimates with evolutionary scores from a protein language model. This decomposes variant effects into: • folding energy • “dark energy,” capturing evolutionary constraints beyond folding

5/ The decomposition reveals distinct disease mechanisms: Gain-of-function and oncogenic variants often preserve stability but strongly perturb functional constraints, whereas many loss-of-function and tumour-suppressor variants are predominantly destabilizing.

2/ Our starting point: inverse-folding models predict stability changes surprisingly well, but they can confuse functional conservation with structural stability. We blend them with the physics-based AWSEM potential to combine complementary signals.

Ezequiel A. Galpern reposted

At last week's Variant Effects Seminar (VESS), @eag91.bsky.social discussed disentangling the biophysical effect of missense variants using protein dark energy. If you missed it, you can now watch it on our YouTube channel at a time to suit you. ⏯️ youtu.be/je5XosFTLPY

youtu.beDisentangling the biophysical effect of missense variants using protein dark energy - E. A. GalpernYouTube video by Variant Effects

"Probing the Dark Energy in the Functional Protein Universe" is now published in @pnas.org 🎉 www.pnas.org/doi/10.1073/...

pnas.orgPNASProceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans...
Ezequiel A. Galpern@eag91.bsky.social

❗New Preprint w/ C Bueno (‪@cabb99.bsky.social‬), IE Sánchez (@nachoquique.bsky.social‬), PG Wolynes & DU Ferreiro (@diegulise.bsky.social‬) We define the Protein Dark Energy and use it to localize and quantify the functional evolutionary constraints on natural proteins arxiv.org/abs/2508.08109

Ezequiel A. Galpern reposted

Applications are open for the @crg_eu PhD Programme! 20 fully funded positions — including one in our group through the Evolutionary Medical Genomics ITN. Join us to develop deep generative models of cross-species data to tackle open questions in disease genetics. www.crg.eu/en/content/t...

Are you looking for a PhD? Join us in Barcelona! You'll dive into a community of >100 PhD students from 30 countries exploring the frontiers of biology. You can also join an online workshop on 6 November (15:00 CET) to learn how to find the right lab for you. More info: www.crg.eu/en/content/t...

Some sites have, on average over all the possible variants, high Dark Energy. In those cases, there is a function beyond protein folding affecting natural selection. This is clearly the case of Enzyme catalytic sites

The idea is simple. For a deleterious mutation, we expect the protein to get destabilized. But how much? Correlations between a ΔΔG DMS and the corresponding ESM-2 scores are not perfect. We define the difference between these two free energies as a ‘Dark Energy’.

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For 15 diverse protein families, we computed the folding mechanisms of hundreds of proteins by simulating an Ising chain of folding elements, or foldons. The energetics is determined by each amino acid sequence. 4/n

Protein topology imposes limits on the variability of folding cooperativity within a family. While most beta and alpha/beta structures exhibit only a few possible mechanisms despite high sequence diversity, alpha topologies allow for diverse folding scenarios. 5/n

We know that closely related proteins usually share similar three-dimensional structures. But differences in their amino acid sequences can lead to distinct folding mechanisms, enabling the natural evolution of diverse biological functions. 2/n

We show that it is possible to use sequence info to go beyond predicting native structures and global stability to infer the folding mechanisms of globular proteins. We mapped a Potts evolutionary energy at the amino-acid level to a coarse-grained description of folding. 3/n

Ezequiel A. Galpern reposted

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