标题：Identity of human epidermal growth factor (EGF) receptor with glycoprotein SA-7: evidence for differential phosphorylation of the two components of the EGF receptor from A431 cells
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1982
卷号：79
期号：16
页码：5026-5030
DOI：10.1073/pnas.79.16.5026
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A 165-kilodalton (kDal) surface glycoprotein encoded by human chromosome 7 (SA-7) had been characterized by using antisera raised against human chromosome 7-containing somatic cell hybrids. We now present evidence that SA-7 is the human receptor for epidermal growth factor (EGF) and that these antisera recognize human-specific determinants. The gene coding for the human EGF receptor is localized to the p12 to p22 region of chromosome 7. We have characterized the 145-kDal/165-kDal EGF receptor doublet of A431 cells after immunoprecipitation of radiolabeled cell extracts with these antisera. We find that a protein with endogenous kinase activity copurifies with the A431 receptor doublet and that both components of the doublet contain phosphotyrosine and phosphothreonine and the 165-kDal component contains phosphoserine as well. Further, although each component of the receptor doublet has an average pI of 7, both display charge heterogeneity and appear to have unique charge isomers. The relationship between the two components of the A431 EGF receptor is discussed.
