Multidimensional Functional Profiling of Human Neuropathogenic FOXG1 Alleles in Primary Cultures of Murine Pallial Precursors


27 February, 2022


Simone Frisari, Manuela Santo, Ali Hosseini, Matteo Manzati, Michele Giugliano and Antonello Mallamaci

FOXG1 is an ancient transcription factor gene mastering telencephalic development. A number of distinct structural FOXG1 mutations lead to the “FOXG1 syndrome”, a complex and heterogeneous neuropathological entity, for which no cure is presently available. Reconstruction of primary neurodevelopmental/physiological anomalies evoked by these mutations is an obvious prerequisite for future, precision therapy of such syndrome. Here, as a proof-of-principle, we functionall scored three FOXG1 neuropathogenic alleles, FOXG1 G224S , FOXG1 W308X , and FOXG1 N232S , against their healthy counterpart. Specifically, we delivered transgenes encoding for them to dedicated preparations of murine pallial precursors and quantified their impact on selected neurodevelopmental and physiological processes mastered by Foxg1: pallial stem cell fate choice, proliferation of neural committed progenitors, neuronal architecture, neuronal activity, and their molecular correlates. Briefly, we found that FOXG1 G224S and FOXG1 W308X generally performed as a gain- and a loss-of-function-allele, respectively, while FOXG1 N232S acted as a mild loss-of-function-allele or phenocopied FOXG1 WT. These results provide valuable hints about processes misregulated in patients heterozygous for these mutations, to be re-addressed more stringently in patient iPSC-derivative neuro-organoids. Moreover, they suggest that murine pallial cultures may be employed for fast multidimensional profiling of novel, human neuropathogenic FOXG1 alleles, namely a step propedeutic to timely delivery of therapeutic precision treatments.