SLC35D3 is largely absent from α-granules, dense granule precursors, and lysosomes in G1ME cells. G1ME cells were doubly infected with recombinant retroviruses expressing GATA-1 and SLC35D3 labeled at either the N-terminus (HA-SLC35D3) or C-terminus (SLC35D3-HA) with HA11 epitope and analyzed 4 days later by IFM and volume deconvolution using Volocity. (A-F) Differentiated G1ME cells were incubated with mepacrine (green) for 30 minutes, then the cells were permeabilized with SLO, fixed, and stained with Ab to the HA tag (red). (I-L) Fixed and permeabilized G1ME cells expressing HA-SLC35D3 were labeled with Abs to HA (green) and either LAMP1 (G-I) or VWF (J-L; red). Right insets show 5-fold magnification of boxed regions; left insets in panels C, F, I, and L, nondeconvolved images with nuclear labeling (blue). Scale bar indicates 10 μm.