Figure 2.

Depletion of plasmid-borne Tlg1p in Δtlg1::LEU2 cells leads to an accumulation of the ER form of CPY (p1CPY). The wild-type and Δtlg1::LEU2 cells containing the GAL1-TLG1 plasmid (JC20) were grown in 1% galactose at 30°C, pelleted, washed, and incubated in 2% glucose medium at 30°C for the indicated periods. Cells (3 OD_600nm) were pulse labeled with [³⁵S]methionine for 15 min and chased for a further 30 min at 30°C. CPY was isolated from cell extracts by immunoprecipitation with 6 μg of anti-CPY antibodies and resolved by 8% SDS-PAGE. The different forms of CPY are indicated on the left. p1CPY, p2CPY, and mCPY represent the ER/early Golgi, late Golgi, and mature vacuolar forms of CPY, respectively. After 2–4 h of incubation in glucose, processing of p1CPY to p2CPY and mCPY is inhibited.