FIG. 1.

Identification of the Pex7p-binding region in Pex13p. (A) Known features of PEX13. The cytosolically exposed SH3 domain (checked box) of the S. cerevisiae peroxisomal membrane protein Pex13p (386 aa) is bound by Pex5p and Pex14p at distinct sites as indicated by the arrows. The two predicted TMDs are marked in dark gray. (B) Analysis of PEX13 fragments for interaction with PEX7 in the yeast two-hybrid assay. The indicated regions of PEX13 were fused to the GAL4 activation domain of plasmid pPC86 and cotransformed with a pPC97-derived plasmid expressing a GAL4 DNA-binding domain-PEX7 fusion into the wild-type strain HF7c. The resulting prototrophs on histidine dropout plates containing 5 mM aminotriazole were considered positive for interaction (+). Numbers flanking the bars indicate the Pex13p amino acid residues that delimit the fragments.