Figure 3. Uptake and degradation of RNA by isolated lysosomes. (A and B) Uptake of RNA by isolated lysosomes. Isolated lysosomes were incubated with purified total RNA (5 μg) in the presence or absence of ATP (energy regeneration system) and/or HSPA8. Levels of RNA remaining in solution outside of lysosomes (A) and levels of RNA resistant to exogenous RNase A (B) were analyzed (n = 3). (C) Lysosomes were incubated with 10 μg of RNA in the presence or absence of ATP. At the indicated times, the levels of RNA remaining outside of lysosomes were analyzed (n = 3). (D) Degradation of RNA by isolated lysosomes. Lysosomes and RNA were incubated with or without ATP. Total levels of RNA in the incubated samples were analyzed (n = 3). (E) Immunogold labeling of RNA in isolated lysosomes incubated with ATP and RNA. Immunogold labeling was performed using an anti-rRNA antibody followed by anti-mouse IgG coupled with 10 nm of gold particles. Gold particles were observed in the lysosomes.