title: Purification of Her-2 extracellular domain and identification of its cleavage site.
abstract: The EGF family of receptors belongs to the tyrosine kinase receptor (TKR) family and plays an important role during embryonic and postnatal development and also in the progression of tumors. Her-2/neu/c-erbB-2, a member of the epidermal growth factor receptor family, can be cleaved into a soluble extra cellular domain (ECD) and a membrane-bound stub fragment. Her-2 ECD from a breast cancer cell line SKBR3 was immunopurified and analyzed with matrix-assisted laser desorption ionization (MALDI) and carboxyl terminal amino acid sequencing. A sequence within the juxtamembrane region (only 11 amino acid residues) PAEQR ASP was identified most likely as a primary site of cleavage, PA EQRASP as a minor site, that generate the ECD. The sites of cleavage are within the signature motif P/GX(5-7)P/G highly conserved in the EGF receptor family.
authors.affiliation: E336/241A, Bristol-Myers Squibb, Experimental Station, Rt. 141 & Henry Clay Road, Wilmington, DE 19880, USA. chaoxingyuan@yahoo.com
authors.forename: Chao-Xing
authors.initials: CX
authors.lastname: Yuan
authors.forename: Amy L
authors.initials: AL
authors.lastname: Lasut
authors.forename: Richard
authors.initials: R
authors.lastname: Wynn
authors.forename: Nicola T
authors.initials: NT
authors.lastname: Neff
authors.forename: Gregory F
authors.initials: GF
authors.lastname: Hollis
authors.forename: Michael L
authors.initials: ML
authors.lastname: Ramaker
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Rupar
authors.forename: Phillip
authors.initials: P
authors.lastname: Liu
authors.forename: Ray
authors.initials: R
authors.lastname: Meade
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001665:Binding Sites; D045744:Cell Line, Tumor; D002846:Chromatography, Affinity / Q000379:methods; D006801:Humans; D007120:Immunochemistry; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000032:analysis / Q000235:genetics; D017434:Protein Structure, Tertiary; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000737:chemistry* / Q000302:isolation & purification*; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
chemical_list: D010446:Peptide Fragments; D018719:Erb-b2 Receptor Tyrosine Kinases