Low molecular weight phosphotyrosine protein phosphatase translocation during cell stimulation with platelet-derived growth factor.
Low Mr phosphotyrosine protein phosphatase (PTP) is a cytosolic enzyme whose activity upon platelet-derived growth factor (PDGF) and insulin receptors has been demonstrated in vivo. In our study we demonstrate that this enzyme, both naturally expressed and overexpressed in NIH/3T3 fibroblasts, translocates from the cytosol to the Triton X-100 insoluble fraction following stimulation with PDGF. It emerges that the phosphorylation of a defined population of PDGF receptors, which is localized in this fraction and seems to be endowed with peculiar features and functions, is particularly affected by low Mr PTP overexpression.
Department of Biochemical Sciences, University of Florence, Italy.
S
S
Rigacci
M
M
Bucciantini
R
R
Marzocchini
A
A
Berti
D016475:3T3 Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D000818:Animals; D000077214:Becaplermin; D001692:Biological Transport; D002455:Cell Division / Q000187:drug effects; D003600:Cytosol / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology; D051379:Mice; D008970:Molecular Weight; D017830:Octoxynol; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D017027:Protein Tyrosine Phosphatases / Q000187:drug effects* / Q000378:metabolism*; D020574:Proto-Oncogene Proteins c-sis; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000187:drug effects / Q000378:metabolism; D017479:Receptors, Platelet-Derived Growth Factor / Q000187:drug effects / Q000378:metabolism; D012995:Solubility; D013347:Subcellular Fractions / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology
D010982:Platelet-Derived Growth Factor; D020574:Proto-Oncogene Proteins c-sis; D000077214:Becaplermin; D017830:Octoxynol; D017479:Receptors, Platelet-Derived Growth Factor; D016392:Proto-Oncogene Proteins pp60(c-src); D017027:Protein Tyrosine Phosphatases