Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1986 Jan;102(1):77-87.
doi: 10.1083/jcb.102.1.77.

The membrane composition of coated pits, microvilli, endosomes, and lysosomes is distinctive in the rat kidney proximal tubule cell

The membrane composition of coated pits, microvilli, endosomes, and lysosomes is distinctive in the rat kidney proximal tubule cell

J S Rodman et al. J Cell Biol. 1986 Jan.

Abstract

The distribution of a number of membrane proteins on plasmalemmal microdomains (microvilli, coated pits) and in endosomes and lysosomes of the proximal tubule epithelial cell was determined in normal rat kidneys by immunofluorescence and immunoelectron microscopy. Two major brush border proteins, 130 and 94 kD, and gamma-glutamyl transpeptidase were detected on the membranes of the microvilli but were not found on membranes of coated pits. Gp330, the Heymann nephritis antigen, and clathrin were localized in coated pits. The lysosomal membrane glycoprotein, lgp120 (Lewis, V., S. A. Green, M. Marsh, P. Vihko, A. Helenius, and I. Mellman, 1985, J. Cell Biol., 100: 1839-1847) was restricted to lysosomes where it co-localized with beta-glucuronidase. Endosomes, identified by preloading with HRP injected 5-15 min before rats were killed, did not contain detectable amounts of any antigen tested. The distribution of the same proteins was also determined in rats given sodium maleate, which is known to slow or reduce protein absorption by the proximal tubule and to cause vacuolation of the endocytic apparatus. After maleate treatment the distribution of microvillar and lysosomal markers was unchanged, but the coated pit markers were redistributed--gp330 was concentrated in newly formed apical vacuoles, and clathrin was diffusely distributed in the apical cytoplasm or on apical coated vesicles. These findings indicate that the membrane composition of microvilli, coated pits, endosomes, and lysosomes is distinctive in the proximal tubule cell; and that gp330, unlike other known coated pit membrane components, is not transferred to endosomes during endocytosis. After maleate treatment, the coated pits lose their clathrin coats, and the corresponding membrane is internalized.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Cell. 1978 Nov;15(3):919-33 - PubMed
    1. Cell. 1984 Feb;36(2):295-307 - PubMed
    1. J Cell Biol. 1980 Sep;86(3):712-22 - PubMed
    1. Kidney Int. 1980 Jun;17(6):771-87 - PubMed
    1. Lab Invest. 1981 Apr;44(4):351-8 - PubMed

Publication types

MeSH terms