While somatosensory over-reactivity is a common feature of autism spectrum disorders such as fragile X syndrome(FXS),the thalamic mechanisms underlying this remain unclear.Here,we found that the developmental eliminat...While somatosensory over-reactivity is a common feature of autism spectrum disorders such as fragile X syndrome(FXS),the thalamic mechanisms underlying this remain unclear.Here,we found that the developmental elimination of synapses formed between the principal nucleus of V(PrV)and the ventral posterior medial nucleus(VPm)of the somatosensory system was delayed in fragile X mental retardation 1 gene knockout(Fmr1 KO)mice,while the developmental strengthening of these synapses was disrupted.Immunohistochemistry showed excessive VGluT2 puncta in mutants at P12–13,but not at P7–8 or P15–16,confirming a delay in somatic pruning of PrV-VPm synapses.Impaired synaptic function was associated with a reduction in the frequency of quantal AMPA events,as well as developmental deficits in presynaptic vesicle size and density.Our results uncovered the developmental impairment of thalamic relay synapses in Fmr1 KO mice and suggest that a thalamic contribution to the somatosensory over-reactivity in FXS should be considered.展开更多
Caspases, a family of cysteine proteases, mediate programmed cell death during early neural development and neurodegeneration, as well as following neurotoxic insults. Notably, accumulating lines of evidence have show...Caspases, a family of cysteine proteases, mediate programmed cell death during early neural development and neurodegeneration, as well as following neurotoxic insults. Notably, accumulating lines of evidence have shown non-apoptotic roles of caspases in the structural and functional plasticity of neuronal circuits under physiological conditions, such as growth-cone dynamics and axonal/dendritic pruning, as well as neuronal excitability and plasticity. Here, we summarize recent progress on the roles of caspases in synaptic refinement.展开更多
基金supported by grants from the National Natural Science Foundation of China(32171014,31970940,31671100,31622027)the Zhejiang Provincial Natural Science Foundation of China(LR18H090001)+1 种基金the Non-profit Central Research Institute Fund of the Chinese Academy of Medical Sciences(2018PT31041)the Program for Introducing Talents in Discipline to Universities,the Fundamental Research Funds for Central Universities(2021FZZX001-37).
文摘While somatosensory over-reactivity is a common feature of autism spectrum disorders such as fragile X syndrome(FXS),the thalamic mechanisms underlying this remain unclear.Here,we found that the developmental elimination of synapses formed between the principal nucleus of V(PrV)and the ventral posterior medial nucleus(VPm)of the somatosensory system was delayed in fragile X mental retardation 1 gene knockout(Fmr1 KO)mice,while the developmental strengthening of these synapses was disrupted.Immunohistochemistry showed excessive VGluT2 puncta in mutants at P12–13,but not at P7–8 or P15–16,confirming a delay in somatic pruning of PrV-VPm synapses.Impaired synaptic function was associated with a reduction in the frequency of quantal AMPA events,as well as developmental deficits in presynaptic vesicle size and density.Our results uncovered the developmental impairment of thalamic relay synapses in Fmr1 KO mice and suggest that a thalamic contribution to the somatosensory over-reactivity in FXS should be considered.
基金supported by grants from the National Natural Science Foundation (31330032,31321091,and 61327902)he National Basic Research Development Program of China (2014CB910203)
文摘Caspases, a family of cysteine proteases, mediate programmed cell death during early neural development and neurodegeneration, as well as following neurotoxic insults. Notably, accumulating lines of evidence have shown non-apoptotic roles of caspases in the structural and functional plasticity of neuronal circuits under physiological conditions, such as growth-cone dynamics and axonal/dendritic pruning, as well as neuronal excitability and plasticity. Here, we summarize recent progress on the roles of caspases in synaptic refinement.