Fig. 4. Analysis of Nup189 protein and the defective phenotype of nup189-disrupted cells. (A) The two-hybrid interaction activity of indicated protein segments is shown (see text for details). (B) Specificity of the anti-Nup189 antibody. Protein samples prepared from a wild-type strain carrying the vector pKD 10 (a) or pKD 10-nup189⁺ (b) were electrophoresed in a gel and immunoblotted. The upper band in b is more intense than in a, while the lower bands are of the same intensity. (C) Colocalization of Nup189 and MAb414 antigen. Merged: Nup189, red; MAb414, green; DAPI, blue. (D) Wild-type (a) and mutant spores (b-d) containing pD817 germinated in an appropriate selective medium at 30°C. pD817 carries a segment of cytochrome P450 reductase gene that is fused with the GFP sequence and is used to visualize the nuclear envelope (Tange et al., 1998). (a) 25 hours, (b) 19 hours, and (c,d) 38.5 hours after transfer into the medium. Red, DAPI; green, GFP. Bars, 2 µm.