Figure 4.

Membrane association of Rab-His₁₂ proteins onto DOGS-NTA–bearing liposomes. A, schematic representation of liposome co-sedimentation assays for testing membrane attachment of the Rab-His₁₂ proteins used in Figs. 2 and 3. B–K, Rh-labeled liposomes (400 nm diameter, 1 mm total lipids in final) were incubated (30 °C, 30 min) with Rab4a-His₁₂ (B), Rab5a-His₁₂ (C), Rab7a-His₁₂ (D), Rab9a-His₁₂ (E), Rab11a-His₁₂ (F), Rab14-His₁₂ (G), Rab1a-His₁₂ (H), Rab3a-His₁₂ (I), HRas-His₁₂ (J), and BSA for a negative control (K) (2 μm final for each) and ultracentrifuged (50,000 rpm, 30 min, 4 °C). The supernatants (sup) and precipitates (ppt) obtained were analyzed by SDS-PAGE and Coomassie Blue staining.