摘要
Ras-related C3 botulinum toxin substrate 1(Racl),a member of the Rho GTPase family which plays important roles in dendritic spine morphology and plasticity,is a key regulator of cytoskeletal reorganization in dendrites and spines.Here,we investigated whether and how Racl modulates synaptic transmission in mouse retinal ganglion cells(RGCs)using selective conditional knockout of Racl(Racl-cKO).Racl-cKO significantly reduced the frequency of AMPA receptor-mediated miniature excitatory postsynaptic currents,while glycine/GABA_A receptor-mediated miniature inhibitory postsynaptic currents were not affected.Although the total GluA1 protein level was increased in Racl-cKO mice,its expression in the membrane component was unchanged.RaclcKO did not affect spine-like branch density in single dendrites,but significantly reduced the dendritic complexity,which resulted in a decrease in the total number of dendritic spine-like branches.These results suggest that Racl selectively affects excitatory synaptic transmission in RGCs by modulating dendritic complexity.
Ras-related C3 botulinum toxin substrate 1(Racl),a member of the Rho GTPase family which plays important roles in dendritic spine morphology and plasticity,is a key regulator of cytoskeletal reorganization in dendrites and spines.Here,we investigated whether and how Racl modulates synaptic transmission in mouse retinal ganglion cells(RGCs)using selective conditional knockout of Racl(Racl-cKO).Racl-cKO significantly reduced the frequency of AMPA receptor-mediated miniature excitatory postsynaptic currents,while glycine/GABA_A receptor-mediated miniature inhibitory postsynaptic currents were not affected.Although the total GluA1 protein level was increased in Racl-cKO mice,its expression in the membrane component was unchanged.RaclcKO did not affect spine-like branch density in single dendrites,but significantly reduced the dendritic complexity,which resulted in a decrease in the total number of dendritic spine-like branches.These results suggest that Racl selectively affects excitatory synaptic transmission in RGCs by modulating dendritic complexity.
基金
supported by grants from the National Natural Science Foundation of China (81790642, 31671078, and 81430007)