Figure 4.

In vitro binding of GST–cav-1 fusion proteins to iNOS. Cytosolic fractions (200 μg of protein) of cytokine-induced HT29 cells were precleared with GST-agarose beads, and incubated with immobilized GST or GST–cav-1 fusion proteins. After washing, bound proteins were eluted in Laemmli buffer and analyzed by Western blotting. Bound iNOS was detected in eluates from GST–caveolin (), and GST–caveolin () beads, but not from beads with immobilized GST, GST–caveolin (1–31), or GST–caveolin (). As a control, GST–cav-1 fusion proteins were visualized by a cav-1-specific antibody revealing that similar amounts of each fusion protein were immobilized in each case. Cav-1 fusion proteins of the expected size are indicated with arrows.