Figure 8 of Dibas, Mol Vis 2008; 14:1770-1783.


Figure 8. Detection of aquaporin-4 (AQP4) in isolated ubiquitinated protein fractions. S5a is a protein subunit of the proteasome that binds ubiquitinated proteins and can be used to purify ubiquitinated proteins. Retinal ubiquitinated proteins were purified on an S5a affinity column (Biomol Inc) before they were eluted with SDS-sample buffer. Next, they were separated on SDS-PAGE then subjected to western blotting using anti-AQP4 antibodies. As shown in this figure, higher molecular weight forms of AQP4 were detected (87 and 100 kDa proteins). Lanes 1-3 are three different retinal preparations from different rats.