Fig. 3.

Export of Eqt-SM from the Golgi is promoted by SM synthesis. (A) Eqt-SM accumulates in the Golgi of SMS1 and SMS2 RNAi cells. HeLa cells were transfected with siRNAs for 2 d, followed by transfected plasmids that direct expression of Eqt-SM and GalT-mKate2, and visualized by deconvolution florescence microscopy at 16 h after the second transfection. Nuclear DNA was stained with Hoechst 33342. Maximum projections of a z series are shown. (Scale bar: 10 μm.) (B) Eqt-SM accumulates in the Golgi of cells treated with D609, a small-molecule inhibitor of SM synthesis. HeLa cells transfected with plasmids that direct expression of Eqt-SM and GalT-mKate2 were incubated with D609 (200 μM) for 4 h. Maximum projections of a z series are shown. (Scale bar: 10 μm.)