Fig. 1. iLR expression in CHO cell lines. Membrane proteins were isolated from wild-type CHO, ldlA, ldlA(iLR) and CHO(iLR) cells as described in Materials and Methods. Samples were either denatured for 5 minutes at 95°C in Laemmli buffer (Laemmli, 1970) (A), or dissolved in Laemmli buffer containing 0.1% SDS and directly subjected to SDS-PAGE under non-reducing conditions (B,C,D). Following transfer to PVDF membrane, iLR was detected with anti-iLR antibody (A,B,D) and LDLR with anti-human LDLR antibody (C,D). The molecular mass markers (kDa) are indicated on the left of each panel.