Fig. 4. Neuronal Nsun2 is essential for synaptic transmission in the prefrontal cortex.
a Electrophysiological recordings from two distinct PFC subregions, ACC (left; n = 10 WT neurons, 15 KO neurons) and PrL (right; n = 11 WT neurons, 14 KO neurons) in WT and Nsun2 KO mouse brain. mEPSCs were recorded from layer V pyramidal neurons at −70 mV (two-tailed t test, **P = 0.007, *P = 0.035). Data are presented as mean values +/− SEM. b Left, glycine content for 50 downregulated synaptic proteins (see Supplementary Table 3) that may contribute to synaptic transmission phenotype, including Neurogranin with 23% glycine. Right, synaptosomes were isolated from Nsun2 KO cortex and immunoblot showed decreased expression of Neurogranin at the synapse in KO cortex (n = 5 WT/5 KO; one-tailed t test, *P = 0.026). Synaptophysin, which was unaltered in our proteomics screen, was used as a loading control. Data are presented as mean values +/− SEM. c Working model for effects of Nsun2 KO on tRNAGly expression, translation of synaptic proteins, and resulting impairments in synaptic transmission. Source data are available as a Source Data file.