UNRAVELLING THE INVOLVEMENT OF THE SYNAPTIC ADAPTOR PROTEIN P140CAP IN HUMAN CORTICAL NEURODEVELOPMENT THROUGH BRAIN ORGANOIDS

p140Cap is an adaptor protein encoded by the SRCIN1 gene, highly expressed in neurons and localized in synaptic terminals.
Previous studies demonstrated that SRCIN1^-/- knock-out (KO) mice display impaired synaptic plasticity, learning and memory deficits, altered actin organization in glutamatergic synapses, and an increased number of inhibitory interneurons, suggesting roles in interneuron migration and progenitor proliferation.
Published scRNA-seq data analysis from dorsal cortical organoids showed significant SRCIN1 expression in different populations and with a temporal evolution, suggesting this model as valid to explore the role of p140Cap in human neurodevelopment.
Dorsal cortical brain organoids were differentiated according to the Velasco’s protocol, starting from human induced pluripotent stem cells, using both a wild type (WT) and a SRCIN1^-/- KO lines generated via CRISPR-Cas9 gene editing.
Morphometric analyses confirmed the expected growth rate, with a similar trend in both genotypes. Immunofluorescence analyses were performed to assess the expression time-course of p140Cap, demonstrating significant levels from 60 days onward.
Neural stem cells, early neuronal progenitor and proliferating cells appeared to be more numerous in KO organoids compared to their respective controls, especially at more advanced stages, as evaluated by immunofluorescence. Parallelly, cortical projection neurons were found to be more numerous in WT organoids, with a complete absence of the SATB2-positive population in KO organoids.
These preliminary findings support a role for p140Cap in proper human neurodevelopment, which is being further investigated through scRNA-seq and electrophysiological analyses.