Figure 2.

Sec24p and Sed5p interact in the two-hybrid system. (A) Schematic representation of the proteins fused to either the Gal4 DNA-binding domain (Sec24p) or the Gal4 transcription-activation domain (Sly1p or the t-SNAREs Sed5p and Ufe1p lacking the transmembrane domain, TM). (B) Colonies of yeast cells expressing the indicated Gal4-domain fusions were grown on nylon filters and subjected to the β-galactosidase color assay by using 5-bromo-4-chloro-3-indolyl β-d-galactoside (X-Gal) as substrate. The interaction of the protein kinase Snf1 and its subunit Snf4 served as positive control. (C) Yeast cells expressing the indicated Gal4 fusion proteins were subjected to β-galactosidase activity measurement using O-nitrophenyl-β-d-galactoside as substrate. Numbers represent the mean values obtained with three individual transformants. NT, not tested.