Reduced perineuronal net expression in Fmr1 KO mice auditory cortex and amygdala is linked to impaired fear-associated memory

Abnormal development of auditory responses in the inferior colliculus of a mouse model of Fragile X Syndrome

“…The peripeduncular (PP) nucleus integrates auditory, motor and hypothalamic signals (Arnault and Roger, 1987). The recruitment of more cells may underlie a stronger activation of auditory-limbic-motor pathways which may lead to behavioral anxiety phenotypes in response to daily environmental sounds in FXS (Miller et al, 1999;Reinhard et al, 2019).…”

Lateralized Expression of Cortical Perineuronal Nets during Maternal Experience is Dependent on MECP2

“…In the human brain, decreased numbers of PNNs are associated with pathological conditions such as decreased memory and motor agility (Brückner et al, 2008;Cabungcal et al, 2013;Enwright et al, 2016;Morawski et al, 2004;Pantazopoulos et al, 2015). Mouse models for varying neurological disorders show abnormal/atypical expression of PNNs which, when removed, can greatly improve the associated pathology or behavioral readouts in these models (Berretta et al, 2015;Krishnan, Lau et al, 2017;Pizzo et al, 2016;Reinhard et al, 2019). We have previously shown that precocious or atypical expression of PNNs caused sensory processing deficits in developing male or adult female mouse models for Rett Syndrome, respectively (Krishnan et al, 2015(Krishnan et al, , 2017.…”

EHMT1 regulates Parvalbumin-positive interneuron development and GABAergic input in sensory cortical areas

“…The timing of PV + interneuron maturation is plastic and depends on sensory input (Marín 2016 ). Interestingly, mouse models for ID and autism spectrum disorders (ASD) show temporal shifts in both directions: earlier maturation in Mecp2 −/y mice, a mouse model for Rett Syndrome (Krishnan et al 2015 , 2017 ; Patrizi et al 2019 ), and delayed maturation in Fmr1 −/y mice, a mouse model for Fragile X Syndrome (Goel et al 2018 ; Harlow et al 2010 ; Reinhard et al 2019 ). Strikingly, PV + neuron-specific knockout of Mecp2 prevented a critical period altogether (Banerjee et al 2016 ; He et al 2014 ), underlining PV + neuron development in sensory cortices as a possible point of convergence in neurodevelopmental disorders.…”