Jul 2026· Journal of Chemical Theory and Computation· 0 citations· 54 references
Medicine
Abstract
Elucidating protein dynamics is crucial for deciphering fundamental biological processes, from enzyme catalysis to cellular signaling, as its dysregulation directly causes protein misfolding diseases such as Alzheimer's and Parkinson's. While artificial intelligence has revolutionized static protein structure prediction, capturing the high-dimensional dynamics of protein folding remains a formidable challenge that limits our ability to fully understand these vital biological phenomena. Here we present DA2-GRASP, a computational framework that overcomes this barrier by integrating deep learning with advanced sampling techniques to map protein folding pathways with unprecedented efficiency and accuracy. DA2-GRASP learns low-dimensional latent representations of protein conformations via a variational autoencoder and combines multidirectional generative sampling guided by local potential energy gradients to efficiently steer conformational transitions along energetically favorable paths, enabling accurate and efficient reconstruction of folding pathways. Our method achieves sublinear computational scaling with sequence length, contrasting the quadratical scaling of molecular dynamics-based conventional approaches, enabling tractable simulations. It maintains high precision in quantifying mutation-induced perturbations to folding thermodynamics, crucial for understanding disease mutations. It also enables atomistic characterization of the folding process of medium-sized proteins such as ubiquitin and small ubiquitin-like modifier (SUMO, ∼80 residues) on standard workstations, a task typically requiring specialized supercomputing platforms such as Anton. Analysis of these proteins provides new mechanistic insights into how structurally similar folds with low sequence identity navigate divergent folding pathways. DA2-GRASP thus establishes a versatile and powerful framework for exploring protein-folding dynamics and their functional consequences.
OrgNet+, a conformational ensemble-aware and orientation-gnostic framework that explicitly incorporates protein structure flexibility during training, is introduced, which substantially reduces intra-ensemble prediction variance while simultaneously improving predictive accuracy.
A. Sarycheva, Aleksandr Shumilov, Petr Popov· Bioinformatics· 0 citations
This mini review traces the evolution of AI-driven methods in protein research, from early residue-contact prediction using coevolutionary information to transformative breakthroughs, the rise of protein language models (PLMs), and the emerging era of generative design and functional modeling.
Guodong Min, Huan Peng· Methods in molecular biology· 0 citations
Molecular dynamics (MD) provides a principled method for modeling equilibrium protein conformational energy landscapes, but its computational cost limits access to long timescales and larger protein systems. Recently, generative protein ensemble models and machine-learned coarse-grained force fields have emerged as complementary approaches for accelerating conformational sampling. However, they are typically developed separately despite modeling the same underlying equilibrium distribution. We introduce UniFlow, the first scalable generative model that unifies protein ensemble generation and machine-learned coarse-grained force fields for molecular dynamics simulation within a single framework. UniFlow employs an internal-coordinate normalizing flow that supports efficient i.i.d. sampling, exact likelihood evaluation, and differentiable energy and force computation. Across diverse protein systems, UniFlow generates ensembles that closely match reference MD simulations, generalizes to proteins beyond its training dataset, and samples substantially faster than diffusion-based ensemble-generation baselines. The same learned density further enables stable long-timescale molecular dynamics simulations. Together, UniFlow paves the way for a unified class of models that bridges generative ensemble modeling with physics-based molecular simulation. Code https://github.com/Harrydirk41/UniFlow.git
Yikai Liu, Ming Chen, Guang Lin· bioRxiv· 0 citations
AlphaFold2's 93 million parameters, shaped by the evolutionary record of protein structure encoded in the Protein Data Bank and in sequence alignments, are conventionally treated only as machinery for converting sequence to structure. We propose they are also a scientific object that can be analyzed directly: a learned encoding of protein conformational organization that can be probed and characterized. By smoothing the Evoformer's weight tensors with a Gaussian convolution and scaling the result, we show that the trained model produces physically structured conformational landscapes. Under perturbation, ubiquitin's native contacts break in the order established by decades of folding experiments. For KaiB, five independently trained models agree that the alternative fold is not recovered under perturbation. For alpha-synuclein, five models produce five different but coherent landscapes, mapping where the training signal has determined the representation and where it has not. Matched-power noise controls confirm that random corruption of equal magnitude produces debris, not conformations. The model learned to predict static structures; the conformational organization visible under perturbation was not an explicit training target, suggesting it emerged as a byproduct of that objective. AlphaFold2's weights appear to encode structural constraints, shaped by evolutionary and structural training data, that extend beyond what unperturbed inference reveals. We call the approach of reading them neural spectroscopy, and Scaled Gaussian Convolution one such protocol.
Sampling rare conformation transitions between metastable states is a central challenge in atomistic simulations. While the committor function serve as an ideal reaction coordinate for driving enhanced sampling, their high-dimensional inputs and complex functional forms limit the efficacy of standard feedforward neural networks in modeling them. Inspired by recent breakthroughs in biomolecular structure prediction, we propose a novel committor learning framework grounded in the AlphaFold 3 paradigm. By integrating a lightweight, differentiable atom-level embedding with a simplified Pairformer architecture, our method inherently captures intricate dynamical features of diverse biosystems without requiring specialized prior knowledge. We demonstrate the superior expressiveness and accuracy of the proposed framework across multiple atomistic processes. For the folding of the chignolin mini-protein, our model reveals the finer-grained structure of its transition state ensemble (TSE) and a detailed bifurcated reaction mechanism. Furthermore, for calixarene host-guest systems, we develop a unified committor model that elucidates how ligand substituents regulate the ratio between distinct binding pathways, offering new perspectives for structure-based drug design.
Jintu Zhang, Zichang Jin, Huifeng Zhao et al.· 0 citations