SNAREopathies · High-throughput screen for disfunctions in GABA-switch in human neuronal models of SNAREopathies

SNARE proteins are essential for brain cell communication. They enable the release of signaling molecules like neurotransmitters and neuropeptides by facilitating the fusion of storage vesicles with the cell membrane. Mutations in genes coding for SNARE proteins cause a group of neurodevelopmental disorders known as SNAREopathies, which can include symptoms such as seizures, developmental delays, autism, and motor or speech impairments. SNAREopathies show very high phenotypic diversity even for patients carrying the same mutation, suggesting that other factors—like the patient's genetic background or other developmental processes—may influence the disease phenotype.One critical process in the brain development is the “GABA-switch”, which determine the GABA neurotransmitter’s action on neurons; early in development, GABA excites neurons; later, it becomes inhibitory. This switch is vital for the brain to form stable and balanced networks, and it depends on precise control of chloride levels inside neurons. Disruption of this switch has been linked to disorders such as epilepsy and autism.My project will use human neurons derived from stem cells carrying patient-specific SNARE variants to study how these variants affect the timing and function of the GABA-switch. I will develop a novel high-throughput, microscopy-based assay that simultaneously measures intracellular chloride concentration and neuronal network activity, allowing precise determination of the timing of the GABA-switch and its relationship to changes in neuronal activity. The functional analysis will be complemented by molecular profiling to uncover underlying mechanisms of affected molecular pathways in SNAREopathies. Finally, I will use my high-throughput microscopy platform to screen candidate compounds with the potential to restore proper signaling in affected neurons. This project will help to better understand SNAREopathies and lay the groundwork for new therapeutic strategies.