Figure 2.

p70 (CLAMP) interacts with the C-terminal end of SR-BI via its first N-terminal PDZ domain (PDZ1). (A) The constructs of various versions of SR-BI are shown schematically. Various deletion mutants of SR-BI fused with GST were produced and affinity-purified with glutathione-agarose beads. N, N terminus; C, C terminus; TM, transmembrane. (B) Rat liver membrane extracts were mixed with glutathione-agarose beads with immobilized C5, C22, C30, or C45-GST. Bound proteins were eluted with the elution buffer, and the eluate was resolved by SDS/PAGE. The proteins were then transferred to nitrocellulose filters, and the filters were immunoblotted with an anti-CLAMP antibody. Proteins bound to the antibody were made visible with an enhanced chemiluminescence kit (Amersham Pharmacia).