摘要
Synapses,the core components of neuronal circuits,rely on precise ultrastructural and molecular organization to facilitate quantal transmission and plasticity,which underpin brain information processing and storage.Cryo-electron tomography(cryo-ET)has emerged as a powerful tool for elucidating the nanoscale architecture of synapses,yet prior studies have largely focused on synaptic vesicles and postsynaptic receptors,leaving other critical components underexplored.Here,we employed cryo-ET to quantitatively analyze subcellular features across over 300 intact hippocampal synapses,revealing:(1)A significant proportion of excitatory synapses(32%)localized to dendritic shafts,while a relatively high proportion of inhibitory synapses targeted dendritic spines(35%),with synaptic clefts displaying four distinct geometries;(2)Diverse structures,including dense core vesicles,membraneless dense granules,and empty clathrin cages were enriched within presynaptic boutons;(3)Mitochondria prevalent in both pre-and postsynaptic regions,showing higher abundance of mitochondrial matrix granules postsynaptically.These findings provide a comprehensive view of the structural organization within hippocampal synapses and suggest fundamental principles governing their subcellular architecture.
基金
supported by the National Natural Science Foundation of China Grant(32200784)
STI2030-Major Projects(2022ZD0205900)
the National Natural Science Foundation of China(32494760,31621002,32461160291)
the Anhui Provincial Natural Science Foundation(2508085J020)
Guangdong Zhujiang Talent Program-Young Top Talents Project(2021QN02Y964)
Shenzhen Fundamental Research Program Grant(JCYJ20210324141013033)
Guangdong Basic and Applied Basic Research Foundation(2021A1515110281)
YTL and ZHZ acknowledge support from the US National Institute of Health(R01GM071940).
