Figure 2.

PM–ER contacts regulate Opi3. (A) Images of yeast cells expressing endogenous Pho88-GFP. Arrows indicate nuclear ER, arrowheads indicate pmaER and asterisks indicate absence of pmaER. (B) Yeast expressing endogenous Tcb3-GFP (green) and RFP-ER (red) expressed from a plasmid. Labels as in (A). (C,D) Yeast expressing Tcb3-GFP staged throughout the cell cycle. Double arrowheads indicate mislocalization of Tcb3-GFP to ER tubules, asterisks indicate absence of pmaER, otherwise labels as in (A). (E) Yeast expressing endogenous Opi3-GFP. Asterisks indicate vacuoles, otherwise labels as in (A). All scale bars, 2 μm. (F) Growth of WT and Δscs2Δice2 yeast overexpressing Osh proteins from plasmids grown on SD media containing galactose in the absence (−) or presence (+Cho) of choline. (G) PE methylation assay for indicated strains expressing Osh3 from a plasmid. Error bars, s.e.m. (H) Growth assays of WT and Δcho2 mutant yeast overexpressing Osh3 from a plasmid grown on SD media containing galactose in the absence of choline. ER, endoplasmic reticulum; GFP, green fluorescent protein; NS, not significant; PC, phosphatidylcholine; PE, phosphatidylethanolamine; PM, plasma membrane; pmaER, PM-associated ER; SD, synthetic-defined; synth, synthesis; WT, wild-type.