Figure 6. Global translation is also enriched in SN branches contacting L7 MN.
A bifurcated SN was cultured with an L7 target MN and an L11 non-target MN (A) for 3 days. Alexa488 (green) was microinjected into the SN as a volume control for imaging (A). Cultured neurons were processed for ICC for puromycin. 100 μM puromycin was applied to cultured neurons for 10 min in the presence of 200 μM emetine. Puromycin incorporated into newly synthesized peptide was detected by anti-puromycin antibody. Representative high magnification images of areas denoted by white squares in (A) are shown in (B), with Alexa488 (green) in the left panel, anti-puromycin in the middle panel (red), and merged images in the right panel. Arrows indicated puromycin immunoreactivity in SN varicosity (B) in the middle panel. Group data (C) show that the puromycin incorporation is greater in SN branches contacting L7 target MNs than in branches contacting non-target L11 target MNs. Error bars represent SEM. *p < 0.05, paired t-test. Scale bars in (A) =100 μm; in (B) =10 μm.