Eps15R is a tyrosine kinase substrate with characteristics of a docking protein possibly involved in coated pits-mediated internalization.

TY - JOUR

T1 - Eps15R is a tyrosine kinase substrate with characteristics of a docking protein possibly involved in coated pits-mediated internalization.

AU - Coda, L

AU - Salcini, A E

AU - Confalonieri, S

AU - Pelicci, G

AU - Sorkina, T

AU - Sorkin, A

AU - Pelicci, P G

AU - Di Fiore, P P

N1 - Keywords: 3T3 Cells; Animals; Bacterial Proteins; Calcium-Binding Proteins; Clathrin; Coated Pits, Cell-Membrane; DNA-Binding Proteins; Endocytosis; Mice; Phosphoproteins; Protein Binding; Protein-Tyrosine Kinases; Repressor Proteins; Transcription Factor AP-2; Transcription Factors

PY - 1998

Y1 - 1998

N2 - eps15R was identified because of its relatedness to eps15, a gene encoding a tyrosine kinase substrate bearing a novel protein-protein interaction domain, called EH. In this paper, we report a biochemical characterization of the eps15R gene product(s). In NIH-3T3 cells, three proteins of 125, 108, and 76 kDa were specifically recognized by anti-eps15R sera. The 125-kDa species is a bona fide product of the eps15R gene, whereas p108 and p76 are most likely products of alternative splicing events. Eps15R protein(s) are tyrosine-phosphorylated following epidermal growth factor receptor activation in NIH-3T3 cells overexpressing the receptor, even at low levels of receptor occupancy, thus behaving as physiological substrates. A role for eps15R in clathrin-mediated endocytosis is suggested by its localization in plasma membrane-coated pits and in vivo association to the coated pits' adapter protein AP-2. Finally, we demonstrate that a sizable fraction of eps15R exists in the cell as a complex with eps15 and that its EH domains exhibit binding specificities that are partially distinct from those of eps15. We propose that eps15 and eps15R are multifunctional binding proteins that serve pleiotropic functions within the cell.

AB - eps15R was identified because of its relatedness to eps15, a gene encoding a tyrosine kinase substrate bearing a novel protein-protein interaction domain, called EH. In this paper, we report a biochemical characterization of the eps15R gene product(s). In NIH-3T3 cells, three proteins of 125, 108, and 76 kDa were specifically recognized by anti-eps15R sera. The 125-kDa species is a bona fide product of the eps15R gene, whereas p108 and p76 are most likely products of alternative splicing events. Eps15R protein(s) are tyrosine-phosphorylated following epidermal growth factor receptor activation in NIH-3T3 cells overexpressing the receptor, even at low levels of receptor occupancy, thus behaving as physiological substrates. A role for eps15R in clathrin-mediated endocytosis is suggested by its localization in plasma membrane-coated pits and in vivo association to the coated pits' adapter protein AP-2. Finally, we demonstrate that a sizable fraction of eps15R exists in the cell as a complex with eps15 and that its EH domains exhibit binding specificities that are partially distinct from those of eps15. We propose that eps15 and eps15R are multifunctional binding proteins that serve pleiotropic functions within the cell.

M3 - Journal article

C2 - 9446614

SN - 0021-9258

VL - 273

SP - 3003

EP - 3012

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

IS - 5

ER -