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
. 1990 May;110(5):1541-8.
doi: 10.1083/jcb.110.5.1541.

Separate endocytic pathways of kinase-defective and -active EGF receptor mutants expressed in same cells

A M Honegger  1 , A Schmidt, A Ullrich, J Schlessinger
Affiliations

Separate endocytic pathways of kinase-defective and -active EGF receptor mutants expressed in same cells

A M Honegger et al. J Cell Biol. 1990 May.

Abstract

Ligand binding to the membrane receptor for EGF induces its clustering and internalization. Both receptor and ligand are then degraded by lysosomal enzymes. A kinase defective point mutant (K721A) of EGF receptor undergoes internalization similarly to the wild-type receptor. However, while internalized EGF molecules bound to either the wild-type or mutant receptors are degraded, the K721A mutant receptor molecules recycle to the cell surface for reutilization. To investigate the mechanism of receptor trafficking, we have established transfected NIH-3T3 cells coexpressing the kinase-negative mutant (K721A) together with a mutant EGF receptor (CD63) with active kinase. CD63 was chosen because it behaves like wild-type EGF receptor with respect to biological responsiveness and cellular routing but afforded immunological distinction between kinase active and inactive mutants. Although expressed in the same cells, the two receptor mutants followed their separate endocytic itineraries. Like wild-type receptor, the CD63 mutant was downregulated and degraded in response to EFG while the kinase-negative mutant K721A returned to the cell surface for reutilization. Intracellular trafficking of EGF receptor must be determined by a sorting mechanism that specifically recognizes EGF receptor molecules according to their intrinsic kinase activity.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Proc Natl Acad Sci U S A. 1978 Jun;75(6):2659-63 - PubMed
    1. J Biol Chem. 1989 Apr 25;264(12):6831-5 - PubMed
    1. Cell. 1979 Apr;16(4):777-85 - PubMed
    1. J Cell Biol. 1979 May;81(2):382-95 - PubMed
    1. Annu Rev Biochem. 1979;48:193-216 - PubMed