FIG. 7.

Degradation of Ub-P-βgal. Cells were grown overnight in SGal minimal medium at 30°C and labeled with ³⁵S labeling mix for 5 min. The cells were resuspended in cycloheximide-containing chase mix, and aliquots were removed at the indicated times. The amount of labeled Ub-P-βgal in the extracts was analyzed by immunoprecipitation with anti-β-galactosidase antibodies followed by SDS-PAGE and quantification by phosphorimager analysis. (A) Degradation of Ub-P-βgal in wild-type (WT), srp1-49, and srp1-31 mutants (strains NOY934, NOY937, and NOY940, respectively). (B) Degradation of Ub-P-βgal in srp1-49 mutant in the presence of the suppressors RPN11 (NOY938) and STS1 (NOY939). Degradation of Ub-P-βgal was also assayed simultaneously in srp1-49 in the presence of vector (NOY937) and in wild-type cells (NOY934) as a control. The quantification of Ub-P-βgal is shown in the graphs below the autoradiograms.