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Soniya, K.

Publications and source records attributed to Soniya, K..

2 recordsLinked to original sources

Learning from and improving upon high-throughputscreens for protein fitness with Generative AI - Application to BBB-crossing AAV design

Deep Science is enabling high-throughput experimentation (HTE) to design novel biological entities with desired properties. E.g., blood-brain-barrier (BBB) crossing adeno-associated virus (AAV) vectors, needed for systemic delivery of gene therapies to brain cells, have been identified through innovative directed evolution assays such as M-CRE-ATE and TRACER. But, even these high-throughput experiments are only able to explore a miniscule portion of the large design space of biological entities. In this paper, we introduce autograd based maximization of protein fitness (AutoMaxProFit) to learn from and improve upon protein designs generated with high-throughput screens. Using a transformer based generative AI network and protein language models, we improve upon the design of a variant previously discovered through HTE, to yield 2x better enrichment in brain endothelial cells, as estimated by molecular dynamics (MD) simulations. This shows that Deep Tech models can learn from the observations generated by Deep Science experiments and go on to find more optimal design candidates for application in Biopharma.

bioinformatics↗

Selective Activation of GPCRs: Molecular Dynamics Investigation of Siponimod's Interaction with S1PR1 and S1PR2

G Protein-Coupled Receptors (GPCRs) are central to drug discovery, accounting for nearly 40% of approved pharmaceuticals due to their regulatory role in diverse physiological processes. Given the high structural similarity among homologues, achieving receptor selectivity while minimizing off-target effects remains a major challenge in designing drugs targeting GPCRs. Sphingosine-1-phosphate receptors (S1PRs), comprising five subtypes, are therapeutically important GPCRs critical for immune and cardiovascular functions. Siponimod, an FDA-approved drug for multiple sclerosis, selectively modulates S1PR1 over S1PR2, unlike earlier S1PR modulators. However, the molecular basis for this selectivity is unclear, as cellular and biochemical assays provide limited insights. In this study, we used long-timescale molecular dynamics simulations to investigate how S1P and Siponimod binding affect S1PR1 and S1PR2 structural dynamics. Both ligands exhibited strong active site binding in both receptors. Crucially, while S1P and Siponimod induced similar activation-linked conformational changes in S1PR1, Siponimod failed to trigger these rearrangements in S1PR2. Specifically, Siponimod binding to S1PR2 led to altered side-chain dynamics of key TM7 residues (viz. Y7.37, F7.38, F7.39) and a drift of transmembrane helix 6 (TM6) towards orientations observed in inactive state. These unique structural features differentiate Siponimods behavior from S1P and explain its lack of inability to modulate S1PR2. Our findings elucidate molecular determinants of Siponimods selectivity towards S1PR1 and highlight these residues as potential differentiators for selective modulator design. This study demonstrates how structural and dynamic insights from atomistic simulations aid rational drug design for targets with high homology.

biophysics↗