Extended Data Fig. 2: Purification and assembly of y20S complex.

a, Sec18 SDS-PAGE gel after the final SEC run. Pooled fractions were frozen and stored. b, Sec17 SDS-PAGE gel after final SEC run. Pooled fractions were frozen and stored. c, Schematic of y20S assembly. Snc1, Sso1, and Sec9 were purified individually before being co-folded for complex formation (Methods). The resulting SNARE complex was added to purified Sec17, EDTA was added, and then purified Sec18 was added. The resulting y20S complex was purified by SEC, and fractions were pooled. The final gel shows reference inputs for Sec18, Sec17, and yeast SNARE complex, the final concentrated y20S complex, and the fractions from SEC that were pooled (yellow lines).