TY - JOUR
T1 - Cytosol- and clathrin-dependent stimulation of endocytosis in vitro by purified adaptors
AU - Smythe, Elizabeth
AU - Carter, Laura L.
AU - Schmid, Sandra L.
PY - 1992/12
Y1 - 1992/12
N2 - Using stage-specific assays for receptor-mediated endocytosis of transferrin (Tfn) into perforated A431 cells we show that purified adaptors stimulate coated pit assembly and ligand sequestration into deeply invaginated coated pits. Late events in endocytosis involving membrane fission and coated vesicle budding which lead to the internalization of Tfn are unaffected. AP2, plasma membrane adaptors, are active at physiological concentrations, whereas API, Golgi adaptors, are inactive. Adaptor-dependent stimulation of Tfn sequestration requires cytosolic clathrin, but is unaffected by clathrin purified from coated vesicles suggesting that soluble and assembled clathrin pools are functionally distinct. In addition to adaptors and cytosolic clathrin other, as yet unidentified, cytosolic factors are also required for efficient coated pit invagination. These results provide new insight into the mechanisms and regulation of coated pit assembly and invagination.
AB - Using stage-specific assays for receptor-mediated endocytosis of transferrin (Tfn) into perforated A431 cells we show that purified adaptors stimulate coated pit assembly and ligand sequestration into deeply invaginated coated pits. Late events in endocytosis involving membrane fission and coated vesicle budding which lead to the internalization of Tfn are unaffected. AP2, plasma membrane adaptors, are active at physiological concentrations, whereas API, Golgi adaptors, are inactive. Adaptor-dependent stimulation of Tfn sequestration requires cytosolic clathrin, but is unaffected by clathrin purified from coated vesicles suggesting that soluble and assembled clathrin pools are functionally distinct. In addition to adaptors and cytosolic clathrin other, as yet unidentified, cytosolic factors are also required for efficient coated pit invagination. These results provide new insight into the mechanisms and regulation of coated pit assembly and invagination.
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U2 - 10.1083/jcb.119.5.1163
DO - 10.1083/jcb.119.5.1163
M3 - Article
C2 - 1447294
AN - SCOPUS:0026446697
SN - 0021-9525
VL - 119
SP - 1163
EP - 1171
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 5
ER -