Immunolocalization of the vacuolar-type (H+)-ATPase from clathrin-coated vesicles.
Proton-translocating ATPases of the vacuolar class (V-ATPases) are found in a variety of animal cell compartments that participate in vesicular membrane transport, including clathrin-coated vesicles, endosomes, the Golgi apparatus, and lysosomes. The exact structural relationship that exists among the V-ATPases of these intracellular compartments is not currently known. In the present study, we have localized the V-ATPase by light and electron microscopy, using monoclonal antibodies that recognize the V-ATPase present in clathrin-coated vesicles. Localization using light microscopy and fluorescently labeled antibodies reveals that the V-ATPase is concentrated in the juxtanuclear region, where extensive colocalization with the Golgi marker wheat germ agglutinin is observed. The V-ATPase is also present in approximately 60% of endosomes and lysosomes fluorescently labeled using alpha 2-macroglobulin as a marker for the receptor-mediated endocytic pathway. Localization using transmission electron microscopy and colloidal gold-labeled antibodies reveals that the V-ATPase is present at and near the plasma membrane, alone or in association with clathrin. These results provide evidence that the V-ATPases of plasma membrane, endosomes, lysosomes, and the Golgi apparatus are immunologically related to the V-ATPase of clathrin-coated vesicles.
Márquez-Sterling
N
N
Department of Physiology, Tufts University School of Medicine, Boston, MA 02111.
Herman
I M
IM
Pesacreta
T
T
Arai
H
H
Terres
G
G
Forgac
M
M
D000818:Animals; D000911:Antibodies, Monoclonal; D002417:Cattle; D002462:Cell Membrane / Q000276:immunology* / Q000648:ultrastructure; D002478:Cells, Cultured; D002966:Clathrin / Q000276:immunology* / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D006056:Golgi Apparatus / Q000276:immunology / Q000648:ultrastructure; D007425:Intracellular Membranes / Q000276:immunology* / Q000648:ultrastructure; D007668:Kidney / Q000166:cytology; D008247:Lysosomes / Q000276:immunology / Q000648:ultrastructure; D016253:Microscopy, Immunoelectron; D006180:Proton-Translocating ATPases / Q000276:immunology*; D014617:Vacuoles / Q000201:enzymology* / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D002966:Clathrin; D006180:Proton-Translocating ATPases