Identifying arginylation inhibitors to attenuate injury-induced neuronal cell death

Attenuating neuronal cell death during the secondary phase of spinal cord injury (SCI) is critical for reducing long-term neurological dysfunction. Recent studies have identified protein arginylation—a posttranslational modification mediated by arginyltransferase 1 (ATE1), as a key driver of neuronal death following SCI. While genetic or pharmacologic suppression of ATE1 confers neuroprotection in both cellular and animal models, the lack of potent, specific, and in vivo-compatible small-molecule ATE1 modulators has hindered progress toward therapeutic development. Building on our prior work in ATE1 biology and assay development, we have established a novel dual- fluorescence, cell-based reporter platform capable of monitoring ATE1 activity in live cells with high sensitivity and compatibility for high-throughput screening (HTS). In this project, we aim to optimize this platform for large- scale compound screening at the R61 phase, and apply it to a ~645,000-compound small-molecule library to identify candidate ATE1 inhibitors at the R33 phase. Lead compounds will be validated through orthogonal biochemical assays, binding specificity studies, and pharmacologic profiling in SCI-relevant cell models, including mouse and human motor neurons. Our goal is to identify small-molecule ATE1 inhibitors with favorable drug-like properties that can serve as lead candidates for therapeutic intervention in SCI, first in animal models and ultimately in human patients. Our multi-PI team brings a unique and complementary set of expertise to this effort. The contact PI, Dr. Fangliang Zhang, a recognized leader in the ATE1/arginylation field, will lead assay development and validation. The multi-PI, Dr. Timothy Spicer, supported by co-investigators Drs. Louis Scampavia and Michael Cameron, brings extensive expertise in HTS and medicinal chemistry. Dr. Aaron Smith will contribute to protein characterization, while Dr. Mousumi Ghosh, an expert in neuronal models and SCI pathophysiology, will lead the pharmacologic evaluation of lead compounds. Together, this interdisciplinary team is well-positioned to advance the discovery of the first pharmacologically viable ATE1 modulators for the treatment of SCI. Project Number: 1R61NS149129-01 | Fiscal Year: 2026 | NIH Institute/Center: National Institute of Neurological Disorders and Stroke (NINDS) | Principal Investigator: FANGLIANG ZHANG (+1 co-PI) | Institution: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE, CORAL GABLES, FL | Award Amount: $368,695 | Activity Code: R61 | Study Section: Special Emphasis Panel[ZRG1 NV-Y (50)] View on NIH RePORTER: https://reporter.nih.gov/project-details/11364729