Figure 1. Proteasome inhibition during early postnatal development provokes the accumulation of ubiquitinated proteins.

Mouse pups were treated with vehicle, MG132 or lactacystin for the first 10 days of life. One hour after the last injection, pups were sacrificed and total brain protein was extracted. A Representative western blot probed for ubiquitin and optical densitometry quantification of ubiquitinated proteins in vehicle-, MG132- and lactacystin-injected pups (left and right panels, respectively). B Chymotrypsin proteasome activity in control, MG132 and lactacystin treated pups (black, gray and white bars, respectively). n = 5 per group. *, p<0.05, **, p<0.01, ***, p<0.001.