| Summary: | Human neural development comprises a phase during which a risk for psychiatric conditions such as schizophrenia is established. Robust evidence has linked voltage-gated calcium channels (VGCCs) to psychiatric illness. However, the biology of VGCCs in the context of human neural development, and particularly the prenatal stages, has not been sufficiently studied. This thesis examines the transcriptional regulation of VGCCs in a model system of neural development, the differentiation of human induced pluripotent stem cells (hiPSCs) into neurons. By applying bioinformatics tools to hiPSC and hiPSC-derived neuron data from dozens of donors, I characterized changes in the abundance and splicing of VGCCs across hiPSC differentiation into neurons. Additionally, motif-based bioinformatics tools were applied to identify candidate regulators of VGCC splicing and abundance. The analyses revealed that as hiPSCs differentiate into neurons, VGCC transcript levels robustly increase. The alternative splicing of CACNA1C, CACNA2D1, and CACNA2D2, including a cell state-specific switch in the utilization of Exons 21 and 22 in CACNA1C, were identified. Analyzing the regions of interest using two different bioinformatics tools identified a binding site for BRUNOL4 and BRUNOL5 upstream of CACNA1C Exon 21, which showed neither evolutionary conservation nor acceleration; and a binding site for HNRNPL near CACNA2D2 Exon 26 showing evolutionary acceleration in primates. Finally, transcription factor (TF) footprinting analyses of ATAC-seq data identified candidate TFs that might regulate multiple VGCC loci, several of which are expressed more highly in human fetal compared with postnatal brain development, including KLF7 and TCF4. Altogether, the results provide a foundation for future research investigating the functions of the identified RBPs and TFs in VGCC transcriptional regulation. The findings also indicate that hiPSCs possess the potential for providing insights into the changes that occur in VGCC transcription and putative mechanisms of VGCC regulation in human neural development and different cell states.
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