Figure 9.

Temperature dependence of ¹²⁵I-labeled PE routing to the cytosol. ▵, Endocytosis was measured (after 30 min at the indicated temperature) as the fraction of cell-associated label resistant to Pronase scraping (see Figure 2). ○, Acquisition of translocation competence was deduced from translocation measurements performed at 37°C on endosomes isolated from cells labeled with 1 μg/ml ¹²⁵I-labeled PE for 30 min at the indicated temperature. □, Translocation temperature dependence was observed using endosomes prepared from cells labeled with ¹²⁵I-labeled PE for 30 min at 37°C. All results are expressed as percentages of the 37°C value.