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Ngo, J. C.

Publications and source records attributed to Ngo, J. C..

3 recordsLinked to original sources

Dense CRISPR Mapping of the WAVE Complex Identifies Pharmacological Modulators of AD-Linked Myeloid Migration

Although genetic risk for Alzheimers disease (AD) strongly converges on microglial pathways, the druggable functional protein regions that control disease-relevant microglial behaviors remain largely unknown. Here, we applied dense CRISPR-Cas9 mutagenesis and CRISPRtile-based functional mapping to the WAVE regulatory complex (WRC), a central regulator of actin remodeling and cell migration. In a pooled CCL2-directed migration assay in human THP-1 myeloid cells, perturbation of NCKAP1L, CYFIP1, and BRK1 impaired migration and revealed divergent effects among WRC paralogs. Residue-level analysis mapped discrete migration-associated functional regions within CYFIP1 and NCKAP1L, including a CYFIP1 regulatory hotspot and a prioritized NCKAP1L region nominated for pharmacological targeting. Human single-nucleus datasets identified NCKAP1L as a microglia-enriched WRC component expressed across diverse microglial states. Machine-learning-guided compound prediction nominated Montelukast sodium and Piperacetazine, which we experimentally validated as negative and positive modulators of chemokine-directed migration, respectively. These findings establish WRC-dependent migration as a pharmacologically tunable myeloid process relevant to AD.

neuroscience↗

AI platform for CRISPR functional mapping and function-based drug design

Conventional structure-based drug design has high clinical failure rates due to the disconnect where binding affinity does not guarantee safe functional modulation. To bridge this gap, we present CRISPRtile, a cloud-based platform for function-based drug design. By deriving library coverage optimization equations and leveraging AI to correct CRISPR guide biases, we generated toxicity and functional landscapes with over threefold error reduction compared to conventional methods. These maps bypass error and orders of magnitude higher computational cost in structure-based pipelines by enabling AI prediction of drug interaction directly from nontoxic functional sequences, while predicting brain penetration with benchmark leading performance. We demonstrate CRISPRtile by mapping the NLRP3 inflammasome and identifying FDA approved drugs with previously unrecognized ability to modulate it, revealing strategies to amplify or inhibit our immune response to homeostatic perturbations. These advances establish a generalizable strategy for the systematic discovery of safe functional modulators.

genetics↗

Molecular Crowding Tunes Material States of Ribonucleoprotein Condensates

Ribonucleoprotein (RNP) granules are membraneless liquid condensates that dynamically form, dissolve, and mature into a gel-like state in response to changing cellular environment. RNP condensation is largely governed by the promiscuous attractive inter-chain interactions, mediated by low-complexity domains (LCDs). Using an archetypal disordered RNP, Fused in Sarcoma (FUS), here we study how molecular crowding impacts the RNP liquid condensation. We observe that the liquid-liquid coexistence boundary of FUS is lowered by polymer crowders, consistent with the excluded volume model. With increasing bulk crowder concentration, RNP partition increases and the diffusion rate decreases in the condensed phase. Furthermore, we show that RNP condensates undergo substantial hardening wherein protein-dense droplets transition from viscous fluid to a viscoelastic gel-like state in a crowder concentration-dependent manner. Utilizing two distinct LCDs that broadly represent the most commonly occurring sequence motifs driving RNP phase transition, we reveal that the impact of crowding is largely independent of LCD charge/sequence patterns. These results are consistent with a thermodynamic model of crowder-mediated depletion interaction where inter-RNP attraction is enhanced by molecular crowding. The depletion force is likely to play key roles in tuning the physical properties of RNP condensates within a crowded intracellular space.

biophysics↗