A Deep Learning-Driven Sampling Technique to Explore the Phase Space of an RNA Stem-Loop

Journal Article · Mon Oct 07 00:00:00 EDT 2024 · Journal of Chemical Theory and Computation

DOI:https://doi.org/10.1021/acs.jctc.4c00669· OSTI ID:2586552

Gupta, Ayush ^[1]; Ma, Heng ^[2]; Ramanathan, Arvind ^[2]; Zerze, Gül H. ^[1]

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1. University of Houston, TX (United States)
2. Argonne National Laboratory (ANL), Argonne, IL (United States)

The folding and unfolding of RNA stem-loops are critical biological processes; however, their computational studies are often hampered by the ruggedness of their folding landscape, necessitating long simulation times at the atomistic scale. Here, we adapted DeepDriveMD (DDMD), an advanced deep learning-driven sampling technique originally developed for protein folding, to address the challenges of RNA stem-loop folding. Although tempering- and order parameter-based techniques are commonly used for similar rare-event problems, the computational costs or the need for a priori knowledge about the system often present a challenge in their effective use. DDMD overcomes these challenges by adaptively learning from an ensemble of running MD simulations using generic contact maps as the raw input. DeepDriveMD enables on-the-fly learning of a low-dimensional latent representation and guides the simulation toward the undersampled regions while optimizing the resources to explore the relevant parts of the phase space. We showed that DDMD estimates the free energy landscape of the RNA stem-loop reasonably well at room temperature. Our simulation framework runs at a constant temperature without external biasing potential, hence preserving the information on transition rates, with a computational cost much lower than that of the simulations performed with external biasing potentials. Here, we also introduced a reweighting strategy for obtaining unbiased free energy surfaces and presented a qualitative analysis of the latent space. This analysis showed that the latent space captures the relevant slow degrees of freedom for the RNA folding problem of interest. Finally, throughout the manuscript, we outlined how different parameters are selected and optimized to adapt DDMD for this system. We believe this compendium of decision-making processes will help new users adapt this technique for the rare-event sampling problems of their interest.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: Cancer Prevention and Research Institute of Texas (CPRIT); Robert A. Welch Foundation; USDOE
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 2586552
• Journal Information: Journal of Chemical Theory and Computation, Journal Name: Journal of Chemical Theory and Computation Journal Issue: 20 Vol. 20; ISSN 1549-9626; ISSN 1549-9618
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English