Mutation of a schizophrenia risk gene SETD1A alters neuronal network activity in human neurons through cAMP/PKA pathway

Using CRISPR/Cas9 to generate an hiPSC line with SETD1A haploinsufficiency and differentiating it into glutamatergic and GABAergic neurons, we found that SETD1A haploinsufficiency resulted in altered neuronal network activity, which was predominantly defined by increased network burst frequency, whereas unchanged global firing activity. In individual neurons, this network phenotype was reflected functionally by increased synchronized synaptic inputs and structurally by increased somatodendritic complexity in both glutamatergic and GABAergic neurons. The transcriptome profile in SETD1A haploinsufficient neurons demonstrated perturbations in gene sets associated with schizophrenia, synaptic transmission, and glutamatergic synaptic function. In addition, transcriptomic data suggested cAMP/PKA pathway might be disturbed in SETD1A haploinsufficient networks, which was further verified by pharmacological experiments. Overall design: Functional and transcriptional analysis of 3 wildtype neuronal hiPSC lines and 3 lines with induced SETD1A haploinsufficiency.