Fig. 2

Characterization of PA28α and PSMD11 overexpressing (OE) mice. a Western blots of proteasomal subunits in retinal lysates containing 30 μg total protein. Bands were visualized using the LiCor Odyssey imaging system. Each protein was analyzed in at least 3 pairs of 1-month-old WT and overexpressing animals. b Retinal morphology of 3-month-old overexpressing and WT mice. Retinas were embedded in plastic, 1 μm cross-sections were stained by toluidine blue and analyzed by light microscopy. Data are taken from one of the five similar experiments; scale bar: 20 μm. c Chymotrypsin-like proteasomal activity in retinal extracts from 1-month-old overexpressing and WT mice; measurements were performed in the presence or absence of ATP, as indicated. The number of measurements was 10, 7, and 5 for WT, PA28α overexpressing, and PSMD11 overexpressing mice, respectively. The data are shown as mean ± SEM; p values determined across individual preparations are indicated in the text. d Fractionation of proteasomal components in retinal extracts from 2-month-old overexpressing and WT mice by size-exclusion chromatography on a Superose-6 Increase column. Proteins in 0.5 ml fractions were probed by western blotting using antibodies against the β1 subunit of the 20S proteasome core, PSMD11 subunit of the 19S proteasome cap, and PA28α subunit of the11S cap. Data are taken from one of the three similar experiments