Requirements for ZNF292 in cortical development and mechanisms of pathogenesis in neurodevelopmental disorders

About This Grant

Recent advances in human genetics defined hundreds of causal variants for Autism Spectrum Disorder (ASD) and other neurodevelopmental disorders (NDDs). However, substantial effort is now required to identify downstream disease processes and guide development of interventions. One such new NOD gene is ZNF292: mutations were recently associated with ASD and other NDDs in humans, but ZNF292 requirements for brain development and consequences of pathogenic mutation have not been studied in any animal or human cellular model. Here, we propose a comprehensive mechanistic investigation of ZNF292, using both established cuttingedge workflows and innovative new approaches to study the consequences of both deficiency and pathogenic mutation at the molecular, cellular, structural, and functional and behavioral circuit levels. We use two complementary experimental systems, mouse models and human pluripotent stem cell (hPSC)-derived neurons, to define ZNF292 requirements for neurodevelopment. We focus initially on hPSC models carrying six pathogenic ZNF292 variants identified in patients with ASD, intellectual disability, and other NOD clinical phenotypes (e.g., microcephaly, epilepsy), and comparison with hPSC lines with constitutive or inducible ZNF292 deficiency. Our preliminary work has already demonstrated shared disruptions of neurodevelopment, transcriptional regulation, and neuronal network function stemming from either ZNF292 deficiency or pathogenic mutation in these models. We also developed conditional and non-conditional mouse knockout models of ZNF292 deficiency and demonstrated that these exhibit NOD-relevant circuit disruptions and, accordingly, altered behavior. Further, we developed cutting-edge tools for temporally controlled reversal of ZNF292 deficiency in our hPSC models, enabling us to investigate the effects of restoring ZNF292 gene function either during development or in mature neurons. Related landmark experiments profoundly changed our understanding of other NDDs by demonstrating that a substantial proportion of chronic NOD phenotypes were reversible, thus spurring the development of therapeutics based on either restoring gene expression or reversing its chronic consequences for neuronal function. In complementary efforts, we continue to model additional cases in this rapidly expanding patient population, linking NOD clinical phenotypes to shared, reversible endophenotypes related to altered neuronal network function. Based upon our preliminary data, we hypothesize that impaired circuit and neuronal network function stemming from chronic reduction of ZNF292 activity contributes substantially to NDDs in this patient population. These deficits may be tractable for molecular or pharmacological treatment to develop interventions. Therefore, together, the experiments performed here will elucidate requirements for and mechanisms by which ZNF292 normally controls brain development and function, will determine how these are disrupted by pathogenic ZNF292 mutation, and could also chart a course towards ZNF292-targeted therapies.