Figure 8.

Splice variants NR1-1 and NR1-2 are required for the maintenance of dendritic spines. A, Schematic structure of the NR1 subunit showing the C-terminal C2 and C2′ cassettes. B, Schematic of the NR1 mRNA (top) showing the four exons (N, C1, C2, C2′) that are differentially spliced to give rise to the NR1 isoforms. The back line indicates the shNR1 target region (not to scale). Schematics of the NR1 rescue clones (NR1_res) used for the analyses of structural requirement are shown at the bottom. Blue areas indicate the mutated shNR1 target region, and gray areas represent the transmembrane domains. C, Summary of spine density at 15 DPT of pyramidal neurons transfected with NR1 rescue splice isoforms together with shNR1 (black bars). Shaded horizontal bars show the average ± 2*SEM of spine density for control (gray) and shNR1 (red) neurons at 15 DPT. *p < 0.05 compared with shNR1 neurons; ^#p < 0.05 compared with control neurons; by ANOVA and Student–Newman–Keuls multiple comparisons test.