Localization of plasmid-encoded RanBP1, sbp1p, and RBD (Sp) in S. pombe sbp1-ΔC genomic mutant cells. Cells transformed with the indicated nmt* promoter-expressing constructs were grown to midlog phase in the absence of thiamine or for the same period in its presence. Cells were fixed with paraformaldehyde, permeabilized, and stained with monoclonal anti-T7 antibody [sbp1p, RanBP1 (m)] or anti-HA antibody [RBD (Sp)], plus FITC-conjugated goat anti-mouse Ig. Cellular DNA was detected by DAPI staining.