Integrin β3 in forebrain Emx1-expressing cells regulates repetitive self-grooming and sociability in mice.

Background: Autism spectrum disorder (ASD) is characterized by repetitive behaviors, deficits in communication, and overall impaired social interaction. Of all the integrin subunit mutations, mutations in integrin β3 (Itgb3) may be the most closely associated with ASD. Integrin β3 is required for normal structural plasticity of dendrites and synapses specifically in excitatory cortical and hippocampal circuitry.

FMRP regulates the subcellular distribution of cortical dendritic spine density in a non-cell-autonomous manner.

Fragile X syndrome (FXS) is the most common form of intellectual disability that arises from the dysfunction of a single gene-Fmr1. The main neuroanatomical correlate of FXS is elevated dendritic spine density on cortical pyramidal neurons, which has been modeled in Fmr1 mice. However, the cell-autonomous contribution of Fmr1 on cortical dendritic spine density has not been assessed.