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Paul Robustelli

@paulrobustelli.bsky.social
626 followers 438 following 132 posts

Assistant Professor at Dartmouth College Computational Biophysics / Disordered Proteins / Molecular Recognition

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Paul Robustelli @paulrobustelli.bsky.social · 08/04/2026
research experience applying mathematical, machine learning or AI approaches for analyzing high dimensional datasets. Applicants interested in applying for a computational role are highly encouraged to include a link to a GitHub repository.
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Paul Robustelli @paulrobustelli.bsky.social · 08/04/2026
Applicants interested in working in computational biophysics should have experience implementing and writing code in Python and experience with computational methods in chemistry or biophysics (such as molecular dynamics simulations) or...
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Paul Robustelli @paulrobustelli.bsky.social · 08/04/2026
Applicants interested in working in experimental biophysics should have research experience in protein biochemistry (ie. protein expression and purification) and/or structural/biophysical characterization of proteins.
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Paul Robustelli @paulrobustelli.bsky.social · 08/04/2026
This position is full-time, non-remote, in-residence at Dartmouth College in Hanover, NH, with start date as early as August 1, 2026. Appointments are typically for a 1-year period. The compensation level will be $55,000 plus benefits.
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Paul Robustelli @paulrobustelli.bsky.social · 08/04/2026
The Robustelli laboratory is hiring a Postbaccalaureate Fellow to work in the group for 1 year with a focus on either experimental or computational biophysics! apply.interfolio.com/184353 This position is ideal for students seeking experience before applying to a PhD program.
apply.interfolio.com
Apply - Interfolio {{$ctrl.$state.data.pageTitle}} - Apply - Interfolio
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Paul Robustelli @paulrobustelli.bsky.social · 21/01/2026
Cool paper! Was starting to worry you’d gotten too cozy in CG-world, but glad to see you’re still willing to churn the GPUs on all-atom IDP models. Looking forward to reading it closely.
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Paul Robustelli @paulrobustelli.bsky.social · 17/12/2025
Also plenty of tasty licks at Nascent Chain’s holiday jam session
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Paul Robustelli @paulrobustelli.bsky.social · 17/12/2025
Happy holidays from our molecular biophysics lab to yours!
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Paul Robustelli @paulrobustelli.bsky.social · 05/12/2025
I have failed to teach my son anything about entropy or times arrow and hereby withdraw my application for tenure.
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Paul Robustelli @paulrobustelli.bsky.social · 23/11/2025
Check out the code github.com/paulrobustel... And the writhe tools python package pypi.org/project/writ...
github.com
GitHub - paulrobustelli/Sisk_IDP_Writhe_2025: Code Accompanying "Characterizing structural and kinetic ensembles of of intrinsically disordered proteins using writhe"
Code Accompanying "Characterizing structural and kinetic ensembles of of intrinsically disordered proteins using writhe" - paulrobustelli/Sisk_IDP_Writhe_2025
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Paul Robustelli @paulrobustelli.bsky.social · 23/11/2025
Our manuscript on using the knot theory descriptor writhe to build kinetic models of IDP dynamics is now out in JCTC pubs.acs.org/doi/full/10.... We think this approach establishes a new state-of-the-art for building markov state models of IDP dynamics.
pubs.acs.org
Characterizing Structural and Kinetic Ensembles of Intrinsically Disordered Proteins Using Writhe
The biological functions of intrinsically disordered proteins (IDPs) are governed by the conformational states they adopt in solution and the kinetics of transitions between these states. We apply wri...
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Thanks if you made all the way through! Heres the paper: www.biorxiv.org/content/10.1... and the trajectories + code: github.com/paulrobustel... Congrats to Jiaqi, Tommy, Borja and Stase on their awesome work!
biorxiv.org
How small molecules stabilize oligomers of a phase-separating disordered protein
Small molecule inhibitors of the intrinsically disordered androgen receptor activation domain have been tested in clinical trials for the treatment of castration-resistant prostate cancer. These compo...
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
In the future, we want to see if we can use ligand induced oligomerization simulations to design ligands that more effectively stablize AR oligomers and modulate AR condensates- which could potentially lead to more potent CPRC therapies.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
We think that stabilizing R2:R2 interfaces (and other less populated R2:R3 and R3:R3 interafces) may also be how EPI-001 lowers the cloud temperature (Tc) of condensation, rigidifies AR condensates, and interferes with RNA pol II partitioning in cellls.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
We think that MD + NMR show that ligands stabilize dynamic oligomerization interfaces of AR AD by bridging interactions between aromatics and forming an extended hydrophobic core that stabilizes helix folding. We see ternary complexes are definitely more rigid than apo dimers, but still dynamic.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
So MD suggests these ligands effectively act as "stickers" to bring aromatic residues together from different monomers together. Good news: so does NMR! @borjaml.bsky.social and Stase found that EPI-001 increases the magnitude of intermolecular NOEs of aromatic protons in Tau-5.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Lets zoom back out to ensemble averages. They key result is that the alkyne linker of 1aa pushes the phenyl groups further apart and gives more rotational freedom. This allows 1aa to simultaneously intercalate into both R2 monomers and form aromatic contacts that stabilize ternary complexes.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Lets take a closer look at the heterogeneity of binding poses and interactions in each kinetically metastable state in the SI. Maybe one day we can try to design ligands to stablize specific substates?
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Lets look at 1aa ternary complexes to see what we're talking about. Ligands tend to bind at one dominant interface, engage aromatic side chains and induce helix folding, but do so with a collection of fuzzy(ish) binding modes. We feel this matches the magnitude of NMR CSPs in experiments well
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
We get valuable insight by looking at ensemble-averaged statistics of these states too. We can see that in apo simulations, residues AWAAAAAQ in R2 associate in a fuzzy manner. Adding ligands extends the apo interaction interfaces and stabilizes and rigidify specific pairs of aromatic contacts.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Here are some snapshots of metastable substates identified by projecting simulation frames onto a kinetically meaningful 2D tCCA latent space. Dig into the SI if you want to see detailed characterizations of each state.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
But what do these dimer and ternary complexes look like? Watch out! Here comes Tommy Sisk to work his IDP writhe + kinetic modeling magic. pubs.acs.org/doi/full/10.... Tommy used tCCA to analyze fluctuations of intramolecular and intermolecular chain writhe and identify metastable complexes
pubs.acs.org
Characterizing Structural and Kinetic Ensembles of Intrinsically Disordered Proteins Using Writhe
The biological functions of intrinsically disordered proteins (IDPs) are governed by the conformational states they adopt in solution and the kinetics of transitions between these states. We apply wri...
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
We see 1000s of dimerization events. Lets go back to our NMR autocorrelation function (ACF) fitting days, and show that if we compute an ACF on time series of dimer contacts - you get a double exponential decay, showing two timescales of dissociation, with ligands slowing down both timescales.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
We ran simulations of two monomers of the AR AD R2 fragment (apo), and in the presence of EPI-002 or 1aa. We see that adding ligands substantially stabilizes the intermolecular association of R2 domains and helicity increases in ternary complexes, in perfect agreement with experiments.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
So what does this look like an atomic, molecular level? A single (or small number of) rigid binding interface(s)? Disordered binding? Fuzzy complexes? Lets get an Anton2 grant and fire-up some unbiased 100 microsecond MD simulations of AR oligomerization in the presence and absence of ligands
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Earlier this year they released a beautiful preprint with a trove of NMR, DLS and condensation assay data showing that EPI-001 stabilizes oligomers of the AR AD, predominantly by strengthening intermolecular interactions formed by the R2 helix of the AR AD. www.biorxiv.org/content/10.1...
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
First the IRB Barcelona team get some important experimental results. In 2021 Stase and co. showed the the R2 helix of the AR AD shows the largest NMR chemical shift perturbations (CSPs) with increasing AR concentration - identifying it as the dominant oligomerization interface of the AR AD.
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
This paper also showed that these ligands partition into AR condensates and lower their cloud temperature (Tc). In vitro and cellular results suggest their activity is potentially linked to their ability to modulate the properties of AR condensates. But how do they this? By what mechanism?
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
In our 2023 NSMB paper, @xsalvatella1.bsky.social and Denes Hnisz led an effort to identify new AR inhibitors www.nature.com/articles/s41..., and Jiaqi found that that MD correctly predicts that more potent ligands with diphenylacetylene moieties have higher affinity to AR AD monomers
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
In 2016, @xsalvatella1.bsky.social used #NMR to identify the binding site of EPI-001: pubs.acs.org/doi/full/10.... In 2022, Jiaqi used MD simulations to model monomer binding modes of EPI-002 (the highest affinity stereoisomer of EPI-001): www.nature.com/articles/s41...
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Small molecules that target the disordered androgen receptor activation domain (AR AD) have shown promise for treating castration resistant prostate cancer (CPCR) in mouse models - but have shown insufficient potency in human trials. If only we understood their mechanisms better....
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Paul Robustelli @paulrobustelli.bsky.social · 22/11/2025
Proud to share our manuscript: "How small molecules stabilize oligomers of a phase-separating disordered protein" www.biorxiv.org/content/10.1... by Jiaqi Zhu and Tommy Sisk, in collaboration with @borjaml.bsky.social , Stase Bielskute-Garcia & @xsalvatella1.bsky.social
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Paul Robustelli @paulrobustelli.bsky.social · 01/11/2025
Does anyone else think saying "this paper isn't a good fit for our journal" is quite a bit less silly than saying that a paper isn't a "striking advance" / "sufficiently timeless" / etc. ?. Who is this goofy form letter language for exactly?
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Paul Robustelli @paulrobustelli.bsky.social · 29/10/2025
Happy to have contributed a few sections on NMR to this very practical and comprehensive community review on benchmarking force fields against experimental data.
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Paul Robustelli @paulrobustelli.bsky.social · 23/10/2025
Today Writhe, our favorite knot theory descriptor for characterizing IDP dynamics, is the star of the lab pumpkin for the annual department carving contest. If you can make sense of the design— I’ll buy you a coffee, bao bun, or wheatgrass shot at the next conference. No substitutions.
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Paul Robustelli @paulrobustelli.bsky.social · 20/10/2025
Fun day at @dartmouthchem.bsky.social serving buldak ramen and explaining the biophysics and structural biology of heat and capsaicin activation of the ion channels to celebrate @acs.org #NationalChemistryWeek.
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Paul Robustelli @paulrobustelli.bsky.social · 17/10/2025
Far out.
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Paul Robustelli @paulrobustelli.bsky.social · 10/10/2025
Also, take note of our 15 (!) exp. refined all-atom IDP ensembles deposited in the protein ensemble database: proteinensemble.org/entries/PED0... If you think you have good method / force field for generating IDP ensembles, you can benchmark your agreement with exp. against these ensembles.
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Paul Robustelli @paulrobustelli.bsky.social · 10/10/2025
Code is here: github.com/paulrobustel...
github.com
GitHub - paulrobustelli/Borthakur_MaxEnt_IDPs_2024: Code Accompanying "Towards accurate, force field independent conformational ensembles of intrinsically disordered proteins" by Borkthakur et al.
Code Accompanying "Towards accurate, force field independent conformational ensembles of intrinsically disordered proteins" by Borkthakur et al. - GitHub - paulrobustelli/Borthakur_MaxE...
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Paul Robustelli @paulrobustelli.bsky.social · 10/10/2025
Our work developing a maximum entropy reweighting method to refine all-atom ensembles of IDPs with extensive NMR and SAXS datasets is now out in @natcomms.nature.com: rdcu.be/eKlK7 Led by @dartmouthchem.bsky.social graduate student Kaushilk Borthakur in collaboration with @bonomimax.bsky.social
rdcu.be
Determining accurate conformational ensembles of intrinsically disordered proteins at atomic resolution
Nature Communications - This study demonstrates how to combine molecular dynamics computer simulations with experimental biophysical data to determine accurate atomic-resolution ensembles of...
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
pubs.acs.org/doi/10.1021/...
pubs.acs.org
Circuit Topology Approach for the Comparative Analysis of Intrinsically Disordered Proteins
Intrinsically disordered proteins (IDPs) lack a stable native conformation, making it challenging to characterize their structure and dynamics. Key topological motifs with fundamental biological relevance are often hidden in the conformational noise, eluding detection. Here, we develop a circuit topology toolbox to extract conformational patterns, critical contacts, and timescales from simulated dynamics of intrinsically disordered proteins. We follow the dynamics of IDPs by providing a smart low-dimensionality representation of their three-dimensional (3D) configuration in the topology space. Such an approach allows us to quantify topological similarity in dynamic systems, therefore providing a pipeline for structural comparison of IDPs.
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
Congrats to Michelle and Korey on their beautiful work! Paper: www.biorxiv.org/content/10.1... Ensembles, Simulation Inputs + Code: github.com/paulrobustel...
biorxiv.org
Monomer binding modes of small molecules that modulate the kinetics of hIAPP amyloid formation
Human islet amyloid polypeptide (hIAPP) forms amyloid fibrils that accumulate in pancreatic β-cells of Type II Diabetes (T2D) patients. Recently discovered small molecules that modulate the kinetics o...
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
...we're super excited to use MD simulations to study how these ligands affect the process of oligomerization of hIAPP and start trying to design more potent aggregation inhibitors. The GPUs are already churning!
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
These simulations gives us a mechanistic framework to begin to understand the structure-activity-relationship of ligands that inhibit or accelerate the aggregation of hIAPP. New @radford-lab.bsky.social work (pubs.acs.org/doi/full/10....) gives us new ligands to look at and...
pubs.acs.org
Kinetic Steering of Amyloid Formation and Polymorphism by Canagliflozin, a Type-2 Diabetes Drug
Amyloid formation is involved in widespread health conditions such as Alzheimer’s disease, Parkinson’s disease, and type-2 diabetes. Amyloid fibrils have a similar cross-β architecture, but fibrils fo...
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
While they're only rarely populated at the same time - these multisite binding mode give us a better understanding of how a network of hydrogen bond donors and acceptors confer pronounced affinity to residues 7_CATQRLANFLV_17.
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
To get more insight into the diversity of binding modes and search for more structured modes - we looked at binding poses where at least 15 residues of hIAPP were in contact with each ligand. This represented 12.9% of bound frames for YX-I-1 but only 3.9% of YX-A-1.
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
Interestingly, the exposed regions of YX-A-1 are quite hydrophobic (cylcohexane and benzene) - and we think this could be part of how it accelerates aggregation into higher order oligomers and protofilaments
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
We see that each ligand has moieties that are consistently buried and others that are consistently exposed across binding modes. We think that buried moieties might confer monomer affinity - while exposed moieties could affect rates of oligomerization into higher order species.
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
Comparing populations of intermolecular interactions we found something unique about this pair: the largest difference is elevated populations of hydrogen bonds with YX-I-1, not increased populations of aromatic stacking interactions -which we usually see in tighter IDP ligands
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Paul Robustelli @paulrobustelli.bsky.social · 27/09/2025
We have a detailed comparison of contact profiles and helicity changes with NMR CSPs from in the SI. We don't see perfect agreement, but observe that the average magnitude of CSPs correlate pretty well with average contact populations and changes in helicity upon and binding.
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