Positional cloning and analysis of prx-5 defined by the ku517 mutation.
(A) Schematic representation of 2 centimorgan (cM) region of chromosome II containing the ku517 mutation. The position of ku517 relative to the dpy-10 and unc-4 genes was determined by three-point mapping. The location of a 7 kb genomic DNA clone able to rescue the ku517 allele (3 out of 3 transgenic lines) is also indicated. (B) Structure of the prx-5 gene. There are two potential cDNA isoforms differing by 6 nucleotides (wormbase.org). The C to T substitution in prx-5(ku517) results in a premature stop codon terminating the encoded protein at amino acid residue 475. The double-arrow indicates the 437 bp deletion in prx-5(tm4948) allele. (C-F) Fluorescence images showing the broad expression pattern of a Pprx-5:GFP fusion protein in C. elegans. The GFP reporter was observed in the embryo (C), intestine (D), hypodermis (E) and neurons (F). (G-J) Images showing the distribution of the GFP-SKL reporter that is the readout of peroxisomal import activity . GFP was localized in peroxisomes as indicated by the punctate pattern in both wild type and elo-5(lf) mutants (G and H). In prx-5(tm4948), GFP is dispersed throughout the cytoplasm, indicating a defect in peroxisomal import (I and J). Bars, 25 µm.