Global Scaling Down of Excitatory Postsynaptic Responses in Cerebellar Purkinje Cells Impairs Developmental Synapse Elimination

作者：Kawata Shinya; Miyazaki Taisuke; Yamazaki Maya; Mikuni Takayasu; Yamasaki Miwako; Hashimoto Kouichi; Watanabe Masahiko; Sakimura Kenji; Kano Masanobu^*

来源：Cell Reports, 2014, 8(4): 1119-1129.

DOI：10.1016/j.celrep.2014.07.014

Synapse elimination is crucial for precise neural circuit formation during postnatal development. We examined how relative differences in synaptic strengths among competing inputs and/or absolute synaptic strengths contribute to climbing fiber (CF) to Purkinje cell (PC) synapse elimination in the cerebellum. We generated mice with PC-selective deletion of stargazin (TARP gamma-2), the major AMPA receptor auxiliary subunit in PCs (gamma-2 PC-KO mice). Whereas relative differences between %26quot;strong%26apos;%26apos; and %26quot;weak%26apos;%26apos; CF-mediated postsynaptic response are preserved, absolute strengths of CF inputs are scaled down globally in PCs of gamma-2 PC-KO mice. Although the early phase of CF elimination is normal, dendritic translocation of the strongest CF and the late phase of CF elimination that requires Ca2+-dependent activation of Arc/Arg3.1 in PCs are both impaired in gamma-2 PC-KO mice. We conclude that, although relative differences in CF synaptic inputs are initially essential, proper synaptic scaling is crucial for accomplishing CF synapse elimination.

• 出版日期2014-8-21