TY - JOUR
T1 - Fibronectin receptor internalization and AP-2 complex reorganization in potassium-depleted fibroblasts
AU - Altankov, Georgi
AU - Grinnell, Frederick
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1995/2
Y1 - 1995/2
N2 - Potassium-depleted fibroblasts are unable to develop polarized morphology and lack coated pits. Experiments were carried out to measure internalization of fibronectin receptors (FNR) in potassium-depleted cells and possible association of FNR with AP-2 complexes after adding potassium back to the cells, which restores cell polarization. AP-2 complexes are the cell surface component of coated pits that contain both clathrin and membrane receptor binding domains. Potassium-depleted fibroblasts endocytosed antibody-tagged FNR and also internalized fluorescent fibronectin that previously had been adsorbed to the substratum. During cell polarization, antibody-tagged FNR reorganized into fibrillar structures along stress fibers beginning from nucleation sites at cell margins. Plasma membrane AP-2 complexes, which were undetectable in potassium-depleted cells, reappeared at the cell surface above the nucleus and then spread toward the cell margins. The results show that endocytosis of FNR can occur at least partially by a coated pit-independent mechanism.
AB - Potassium-depleted fibroblasts are unable to develop polarized morphology and lack coated pits. Experiments were carried out to measure internalization of fibronectin receptors (FNR) in potassium-depleted cells and possible association of FNR with AP-2 complexes after adding potassium back to the cells, which restores cell polarization. AP-2 complexes are the cell surface component of coated pits that contain both clathrin and membrane receptor binding domains. Potassium-depleted fibroblasts endocytosed antibody-tagged FNR and also internalized fluorescent fibronectin that previously had been adsorbed to the substratum. During cell polarization, antibody-tagged FNR reorganized into fibrillar structures along stress fibers beginning from nucleation sites at cell margins. Plasma membrane AP-2 complexes, which were undetectable in potassium-depleted cells, reappeared at the cell surface above the nucleus and then spread toward the cell margins. The results show that endocytosis of FNR can occur at least partially by a coated pit-independent mechanism.
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U2 - 10.1006/excr.1995.1038
DO - 10.1006/excr.1995.1038
M3 - Article
C2 - 7843274
AN - SCOPUS:0028925156
SN - 0014-4827
VL - 216
SP - 299
EP - 309
JO - Experimental Cell Research
JF - Experimental Cell Research
IS - 2
ER -