Fig. 4. The 50 kDa core protein bearing heparan sulfate GAGs corresponds to the single C. elegans orthologue of vertebrate syndecans. (A) mRNA was isolated from wild-type and sdn-1 (ok449) mutant strains and RT-PCR was performed using primers in the positions indicated in Fig. 5A. The migration of the RTPCR products, by agarose gel electrophoresis, is shown. wt, wild-type worms; sdn-1, sdn-1 (ok449) mutant worms. (B) Northern blot analysis carried out using mRNA (30 µg samples) obtained as described from wild-type and sdn-1 (ok449) mutant worms. Blots were probed with specific ³²P-labeled 632 bp hybridization probes. The migration of 18S and 28S ribosomal sub-units is shown as a standard. (C) Western blot analysis of wild-type and sdn-1 (ok449) mutant worms. Samples were obtained by sonication in PBS and protease inhibitors, treated directly with heparitinase, separated on a 10% polyacrylamide slab gel and visualized with anti--heparan sulfate antibody. Total absence of the 50 kDa core protein was observed in the sdn-1 mutants (low and high exposure), in contrast to its prominence in wild-type samples, whereas the other two core proteins (80 and 30 kDa) remained almost unaffected (high exposure).