Stimulation by phospholipids of a protein-tyrosine-phosphatase containing two src homology 2 domains.
PTP1C, a protein-tyrosine-phosphatase (protein-tyrosine-phosphate phosphohydrolase, EC 3.1.3.48) containing two src homology 2 domains, is poorly active when assayed with various protein substrates in vitro. Its activity is stimulated > 1000-fold by anionic phospholipids when myelin basic protein or mitogen-activated protein kinase is used as substrate but reduced in the presence of several other substrates. Data are presented to indicate a direct interaction of the enzyme with phospholipids. Enzyme stimulation directed only toward certain specific substrates is interpreted by assuming that these compounds also bind to the phospholipid vesicles where they will be subjected to rapid enzymatic attack. A possible regulation of PTP1C by its translocation to the cell membrane is hypothesized.
Zhao
Z
Z
Department of Biochemistry, University of Washington, Seattle 98195.
Shen
S H
SH
Fischer
E H
EH
D000595:Amino Acid Sequence; D000818:Animals; D016391:Genes, src; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D009113:Muramidase / Q000378:metabolism; D010446:Peptide Fragments / Q000302:isolation & purification; D010743:Phospholipids / Q000494:pharmacology*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D017027:Protein Tyrosine Phosphatases / Q000235:genetics* / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000235:genetics*; D011817:Rabbits; D011972:Receptor, Insulin; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014357:Trypsin
D010446:Peptide Fragments; D010743:Phospholipids; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D005982:Glutathione Transferase; D011494:Protein Kinases; D011505:Protein-Tyrosine Kinases; D011972:Receptor, Insulin; D016392:Proto-Oncogene Proteins pp60(c-src); D017027:Protein Tyrosine Phosphatases; D009113:Muramidase; D014357:Trypsin