Divergent phenotypes in germline versus conditional mutant mouse models of Sifrim-Hitz-Weiss Syndrome

Autor: Sarah Larrigan, Shrilaxmi Joshi, Pierre Mattar
Rok vydání: 2023
DOI: 10.1101/2023.02.15.528754
Popis: Chromatin remodellers are among the most important risk genes associated with neurodevelopmental disorders (NDDs), however, their functions during brain development are not fully understood. Here, we focused on Sifrim-Hitz-Weiss Syndrome (SIHIWES) – a brain overgrowth/intellectual disability disorder caused by mutations in theCHD4chromodomain helicase gene. We utilized mouse genetics to excise theChd4ATPase/helicase domain – either in the germline, or conditionally in the developing telencephalon. Conditional heterozygotes exhibited little change in cortical size and cellular composition, and had only subtle behavioral phenotypes. Telencephalon-specific conditional knockouts had marked reductions in cortical growth, reduced numbers of upper-layer neurons, and exhibited alterations in anxiety and repetitive behaviors. Despite the fact that germline heterozygotes exhibited comparable growth defects, they were unaffected in these behaviors, but instead exhibited female-specific alterations in learning and memory. These data reveal unexpected phenotypic divergence arising from differences in the spatiotemporal deployment of loss-of-function manipulations, underscoring the importance of context in chromatin remodeller function during neurodevelopment.Graphical Abstract.
Databáze: OpenAIRE