Endocytosis and Lysosomal Delivery of Tissue Plasminogen Activator - Inhibitor 1 Complexes in Hep 6 2 Cells
نویسندگان
چکیده
Receptor-mediated endocytosis of tissue-type plasminogen activator (t-PA)-plasminogen activator inhibitor type 1 (PAl-1) complexes results in their clearance by Hep G2 cells. After complexes are internalized, the t-PA component is degraded. However, neither the locus of intracellular catabolism nor the fate of PAL1 has been elucidated. To characterize these aspects of t-PA.PAI-1 catabolism, the subcellular distribution of a prebound cohort of ligand molecules was delineated after internalization at 37°C. 1251-t-PA*PAI-1 and t-PA.lZ51PAI-1 were compared in separate experiments. After ligand uptake, intracellular vesicles were separated on density gradients. Internalized 1251-t-PA.PAI-l concentrated initially in endosomes. After 20 minutes of uptake, the complex began to appear in lysosomes. Subsequently, low molecular
منابع مشابه
Endocytosis and lysosomal delivery of tissue plasminogen activator-inhibitor 1 complexes in Hep G2 cells.
Receptor-mediated endocytosis of tissue-type plasminogen activator (t-PA)-plasminogen activator inhibitor type 1 (PAI-1) complexes results in their clearance by Hep G2 cells. After complexes are internalized, the t-PA component is degraded. However, neither the locus of intracellular catabolism nor the fate of PAI-1 has been elucidated. To characterize these aspects of t-PA-PAI-1 catabolism, th...
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