Figure 4.

The invertase maturation delay in Δemp24 cells is not exacerbated in p24Δ4 and p24Δ8 cells. Cells expressing invertase from the CPY promoter were pulse labeled for 10 min and chased for 10 min. Spheroplasts were prepared and centrifuged to obtain the cytoplasmic (I, internal) and periplasmic (E, external) fractions. Invertase was immunoprecipitated, resolved by SDS–PAGE, and detected by autoradiography. Migration positions of core-glycosylated (ER form) and hypo- and hyperglycosylated (Golgi forms) are indicated.