FIGURE 3.

Ypt7p diminishes the inhibition of proteoliposome fusion by Yck3p but does not inhibit the Yck3p phosphorylation of Vps41p. A, lipid mixing between liposomes bearing Qab-SNAREs (acceptor) and R-SNARE (donor) ± Ypt7p (200 nm for acceptor proteoliposomes and 25 nm for donor proteoliposomes). All reactions contained 6 mm MgCl₂ and 1 mm ATP. HOPS (75 nm) and Yck3p (3 or 6 μm) was added as indicated. Vam7p (600 nm), Sec17p (1.2 μm), and Sec18p (1.4 μm) were added to all tubes at time 0, which followed a 10-min preincubation of the plate at 27 °C. B, selected reactions from panel A were incubated with 0.4% SDS at 90 °C for 5 min followed by SDS-PAGE and immunoblot for Vps41p.