Fig. 5.

Isolation of Jurkat cell DRMs. Jurkat cells were treated with Cdt holotoxin for 2 h and DRMs were isolated as described in Experimental procedures. Two distinct low-buoyant-density bands, designated DRM1 and DRM2, were obtained. The composition of these bands was analysed to ascertain that they were indeed lipid rafts. DRM1, DRM2 and the soluble fraction were assessed for cholesterol (bottom) and GM1 (dot blot). The protein profile of the fractions was assessed by Western blot analysis for the presence of the raft-associated protein, Lck, which was enriched in these fractions. In contrast, the transferrin receptor (CD71), a non-raft-associated protein, was found in the soluble fraction. Results are representative of three experiments.