FIGURE 4.

Peroxisomal Pnc1p import depends on Pex21p and Gpd1p. Cells of wild-type strain as well as Δpex18, Δpex21, and Δgpd1 mutants were grown in oleate medium. The postnuclear supernatant was prepared and further analyzed by density gradient centrifugation (left panel). Fractions were collected from the bottom (fraction 1). Equal volumes of indicated gradient fractions were analyzed by immunoblotting using antibodies against GFP, Fox3p, Pcs60p, Kar2p, Porin, and Fbp1p as indicated. Fluorescence microscopy of plasmid-encoded Pnc1p-GFP and the peroxisomal marker protein DsRed-SKL in cells from wild-type and peroxisomal mutant strains Δpex7, Δpex18, Δpex21, and Δgpd1 (right panel). The data revealed that the peroxisomal localization of Pnc1p depends on the presence of Gpd1p, Pex7p, and Pex21p.