标题：Direct identification of residues of the epidermal growth factor receptor in close proximity to the amino terminus of bound epidermal growth factor.
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：1992
卷号：89
期号：16
页码：7801-7805
DOI：10.1073/pnas.89.16.7801
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We have recently developed a kinetically controlled, step-wise affinity cross-linking technique for specific, high-yield, covalent linkage of murine epidermal growth factor (mEGF) via its N terminus to the EGF receptor. EGF receptor from A431 cells was cross-linked to radiolabeled mEGF (125I-mEGF) by this technique and the 125I-mEGF-receptor complex was purified and denatured. Tryptic digestion of this preparation gave rise to a unique radiolabeled peptide that did not comigrate with trypsin-treated 125I-mEGF in SDS/Tricine gels but that could be immunoprecipitated with antibodies to mEGF. The immunoprecipitated peptide was isolated by electrophoresis in SDS/Tricine gels, eluted, and sequenced. The sequence was found to correspond to that of a tryptic peptide of the EGF receptor beginning with Gly-85, which is in domain I, a region N terminal to the first cysteine-rich region of the receptor. Selective loss of signal in the 17th sequencing cycle suggests that the point of attachment of N-terminally modified 125I-mEGF to the receptor is Tyr-101. The data presented here provide identification by direct protein microsequencing of a site of interaction of EGF and the EGF receptor.
