Reduced CYFIP1 in human neural progenitors as 15q11.2 deletion model: donor specific dysregulation of schizophrenia/epilepsy genes

Deletions at 15q11.2 have been established to increase risk for multiple neurodevelopmental disorders (NDDs) including schizophrenia and epilepsy, yet show variable expressivity between individuals. To investigate the potential role of CYFIP1, a gene within the locus, we carried out knockdown experiments in human neural progenitor cells derived from 15q11.2 neutral induced pluripotent stem cells. Transcriptional profiling and cellular assays support a prominent role for CYFIP1 in cytoskeletal remodeling across all lines examined. Validating the utility of this model for study of disease, genes implicated in schizophrenia and epilepsy but not other disorders or traits unrelated to the deletion, were enriched among mRNAs dysregulated following knockdown. Importantly, and consistent with the variable expressivity of 15q11.2 deletions, the magnitude of disease-related effects varied between donor lines. Towards mechanisms, FMRP targets and synaptic genes were overrepresented among dysregulated mRNAs and as such may contribute to the schizophrenia and epilepsy effects we observe. Further model validation, and new candidate epilepsy genes, comes from machine-learning analyses showing a striking similarity between a subset of dysregulated transcripts and well-established epilepsy genes. Results provide support for an important contribution of CYFIP1 in 15q11.2 mediated risk for NDDs and demonstrate that disease-related biological signatures are evident prior to neuronal differentiation. This new human model of disease will be useful in identifying compounds that could ameliorate outcomes in deletion carriers. Overall design: Investigation of CYFIP1 shRNA knockdown in three neural progenitor cell lines derived from induced pluripotent stem cells (3 control samples and 3 knockdown samples analyzed in each line)

18

Nebel RA, Zhao D, Pedrosa E, Kirschen J, Lachman HM, Zheng D, Abrahams BS