ApoER2 expression decreases APP-CTFs in DAPT-treated LRP1-null CHO cells. (A) ApoER2 decreases both endogenous hamster APP-CTFs and human APP695-CTFs. LRP1-null CHO cells were transiently transfected with pcDNA (control), APP695-Myc (APP) or APP695-Myc along with ApoER2-HA (APP/ApoER2). Cells were then treated with DAPT 10 μM and protein association to lipid rafts was analyzed as in Figure 8. High sensitivity films were used for endogenous APP-CTFs detection. (B), Lubrol-extracted proteins from lysates obtained in (A) were subjected to 10% SDS-PAGE. Blots were probed with anti-ApoER2, anti-APP and anti-actin or antibodies. Similar APP protein levels were detected in APP695-Myc and in APP695-Myc + ApoER2-HA transfected cells. Remnants of ApoER2 detection after stripping and reblot are indicated by an asterisk.