Biology subjects

Kuan, W.-L.

Publications and source records attributed to Kuan, W.-L..

3 recordsLinked to original sources

bioRxiv2026

Cross-platform multi-laboratory screening identifies HUWE1, USP33 and USP20 as negative-regulators of autophagy or mitophagy with relevance to neurodegeneration

Autophagy and mitophagy are essential cellular processes implicated in neurodegenerative diseases, yet few tractable targets have been robustly validated for therapeutic modulation of these pathways. In an industry-academia consortium we carried out an extensive literature review and expert curation, leading to selection of 29 genes previously reported to enhance autophagy upon genetic or pharmacological modulation. These genes were classified based on whether downregulation or overexpression induced autophagic activity. Using siRNA knockdown, small-molecule modulators, and transient transfection approaches, we systematically screened these targets in parallel across HeLa and HEK-293 cell lines using high- and low-content phenotypic imaging. Promising candidates were further evaluated in induced pluripotent stem cell (iPSC)-derived neurons and in Drosophila models. Three targets emerged as top candidates: HUWE1 downregulation consistently enhanced autophagy and aggregate clearance, while USP33 downregulation promoted mitophagy. We also identified USP20, a close homologue of USP33, as an inhibitor of mitophagy, a role not previously assigned to this protein. These effects on autophagy/mitophagy were corroborated in Drosophila, highlighting their potential functional relevance across species. This cross-platform, multi-laboratory study establishes a framework for identifying and validating regulators of autophagy and mitophagy and provides a route which enables a comprehensive reassessment of the current target literature in this field. The validation of HUWE1, USP20, and USP33 as candidate therapeutic targets offers new opportunities for intervention in neurodegenerative diseases.

neuroscience↗

bioRxiv2020

Criticality as a measure of developing proteinopathy in engineered human neural networks

A patterned spread of proteinopathy represents a common characteristic of many neurodegenerative diseases. In Parkinsons disease (PD), misfolded forms of alpha-synuclein proteins aggregate and accumulate in hallmark pathological inclusions termed Lewy bodies and Lewy neurites, which seems to affect selectively vulnerable neuronal populations and propagate within interconnected neuronal networks. Research findings suggest that these proteinopathic inclusions are present at very early timepoints in disease development, even before strong behavioural symptoms of dysfunction arise, but that these underlying pathologies might be masked by homeostatic processes working to maintain the function of the degenerating neural circuits. This study investigates whether inducing the PD-related alpha-synuclein pathology in engineered human neural networks can be associated with changes in network function, and particularly with network criticality states. Self-organised criticality represents the critical point between resilience against perturbation and adaptational flexibility, which appears to be a functional trait in self-organising neural networks, both in vitro and in vivo. By monitoring the developing neural network activity through the use of multielectrode arrays (MEAs) for a period of three weeks following proteinopathy induction, we show that although this developing pathology is not clearly manifest in standard measurements of network function, it may be discerned by differences in network criticality states.

neuroscience↗

bioRxiv2020

GAPDH controls extracellular vesicle biogenesis and enhances therapeutic potential of EVs in silencing the Huntingtin gene in mice via siRNA delivery

Extracellular vesicles (EVs) are biological nanoparticles with important roles in intercellular communication and pathophysiology. Their capacity to transfer biomolecules between cells has sparked efforts to bioengineer EVs as drug delivery vehicles. However, a better understanding of EV biogenesis mechanisms and function is required to unleash their considerable therapeutic potential. Here we demonstrate a novel role for GAPDH, a glycolytic enzyme, in EV assembly and secretion, and we exploit these findings to develop a GAPDH-based methodology to load therapeutic siRNAs onto EVs for targeted drug delivery to the brain. In a series of experiments, we observe high levels of GAPDH binding to the outer surface of EVs via a phosphatidylserine binding motif, designated as G58, and discover that the tetrameric nature of GAPDH promotes extensive EV aggregation. Studies in a Drosophila EV biogenesis model demonstrate that GAPDH is absolutely required for normal generation of intraluminal vesicles in endosomal compartments and promotes vesicle clustering both inside and outside the cell. Fusing a GAPDH-derived G58 peptide to dsRNA-binding motifs permits highly efficient loading of RNA-based drugs such as siRNA onto the surface of EVs. Such vesicles efficiently deliver siRNA to target cells in vitro and into the brain of a Huntingtons disease mouse model after systemic injection, resulting in silencing of the huntingtin gene in multiple anatomical regions of the brain and modulation of phenotypic features of disease. Taken together, our study demonstrates a novel role for GAPDH in EV biogenesis, and that the presence of free GAPDH binding sites on EVs can be effectively exploited to substantially enhance the therapeutic potential of EV-mediated drug delivery to the brain.

neuroscience↗