Fig. 5. The [³⁵S]DRM conversion product is PrP. Conversion reactions were performed as in Figure 4 using microsomes and [³⁵S]DRMs (with PI-PLC; lanes 1–5) or PI-PLC-digested [³⁵S]PrP-sen (lanes 6–12). Conversion reaction products were immunoprecipitated using either R30 antiserum against a mouse PrP synthetic peptide (89–103; lanes 3, 5, 10 and 12) or R30 pre-absorbed with peptide 89–103 (lanes 4 and 11). Conversion reactions without immunoprecipitation (lanes 1, 2 and 6–9) are shown for comparison. PK^– and PK⁺ indicate lanes without and with PK digestion, respectively. PK⁺ lanes contain nine times the reaction equivalents loaded in PK^– lanes, except for the immunoprecipitated samples where the entire reaction was PK digested. Arrows indicate PK-resistant [³⁵S]PrP-res bands (lanes 2, 3, 9 and 10). The data are representative of a single experiment performed in duplicate.