English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
  A431 cell variants lacking the blood group A antigen display increased high affinity epidermal growth factor-receptor number, protein-tyrosine kinase activity, and receptor turnover.

Defize, L. H., Arndt-Jovin, D. J., Jovin, T. M., Boonstra, J., Meisenhelder, J., Hunter, T., et al. (1988). A431 cell variants lacking the blood group A antigen display increased high affinity epidermal growth factor-receptor number, protein-tyrosine kinase activity, and receptor turnover. The Journal of Cell Biology, 107(3), 939-949. doi:10.1083/jcb.107.3.939.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/11858/00-001M-0000-002D-4864-3 Version Permalink: http://hdl.handle.net/11858/00-001M-0000-002D-4866-0
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Defize, L. H., Author
Arndt-Jovin, D. J.1, Author              
Jovin, T. M.1, Author              
Boonstra, J., Author
Meisenhelder, J., Author
Hunter, T., Author
de Hey, H. T., Author
de Laat, S. W., Author
Affiliations:
1Department of Molecular Biology, MPI for biophysical chemistry, Max Planck Society, ou_578628              

Content

show
hide
Free keywords: -
 Abstract: The epidermal growth factor receptor (EGF-R) of human A431 cells bears an antigenic determinant that is closely related to the human blood group A carbohydrate structure. Labeling studies with blood group A reactive anti-EGF-R monoclonal antibodies and various lectins revealed that A431 cultures are heterogeneous with respect to blood group A expression. We have isolated clonal variants of these cells that either express (A431A+ cells) or completely lack (A431A- cells) the blood group A specific N-acetyl-D-galactosamine (GalNAc) residue. We show that this difference is due to the absence of a UDP-GalNAc:Gal transferase activity in A431A- cells. Subsequently, we have compared EGF-R functioning in these cell lines. Scatchard analysis of EGF-binding shows that in A431A- cells 6.3% of the EGF-R belongs to a high affinity subclass (Kd = 0.4 nM) while in A431A+ this subclass represents only 3.2% of the total receptor pool. The elevated level of high affinity receptors in A431A- cells is accompanied by a parallel increase in receptor protein- tyrosine kinase activity. In membrane preparations of A431A- cells, receptor autophosphorylation as well as phosphorylation of a tyrosine-containing peptide substrate is 2-3-fold higher as compared with A431A+ cells. In intact A431A-cells, the difference in receptor activity is measured as a 2-3-fold elevated level of receptor phosphorylation and a 2-3-fold higher abundance of phosphotyrosine in total cellular protein in A431A- cells. In addition, [35S]methionine pulse-chase experiments showed a ligand-independent increase in turnover of EGF-R in A431A- cells: the receptor's half life in these cells is 10 h as compared with 17 h in A431A+ cells. Our results suggest a possible involvement of GalNAc residue(s) in determining EGF-R affinity, protein-tyrosine kinase activity and turnover in A431 cells. Furthermore, our results indicate that high affinity EGF-R are the biologically active species with respect to protein-tyrosine kinase activity.

Details

show
hide
Language(s): eng - English
 Dates: 1988-09
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: Peer
 Identifiers: DOI: 10.1083/jcb.107.3.939
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: The Journal of Cell Biology
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: 107 (3) Sequence Number: - Start / End Page: 939 - 949 Identifier: -