Protein tyrosine phosphatase-1C is rapidly phosphorylated in tyrosine in macrophages in response to colony stimulating factor-1.
An approximately 64-kDa cytoplasmic protein is rapidly phosphorylated in tyrosine in the response of macrophages to colony stimulating factor-1. To identify this protein, BAC1.2F5 macrophages were incubated with or without colony stimulating factor-1, the phosphotyrosine-containing portion of their cytosolic fractions subjected to size exclusion chromatography, and the 45-70-kDa fraction further fractionated by reverse phase high pressure liquid chromatography (RP-HPLC). Tryptic peptides of pooled RP-HPLC fractions from stimulated cells (containing the approximately 64-kDa protein and an approximately 54-kDa protein) and from unstimulated cells (containing the approximately 54-kDa protein alone), were sequenced directly. All seven readable sequences of 8 sequenceable peptides present uniquely in the stimulated fraction were present in the sequence of the src homology 2 domain-containing protein tyrosine phosphatase-1C (PTP-1C). The identity of the approximately 64-kDa protein was confirmed by Western blotting with an antibody raised to a PTP-1C peptide. The rapid, growth factor-induced tyrosine phosphorylation of PTP-1C suggests that it may be involved in very early events in growth factor signal transduction.
Yeung
Y G
YG
Department of Developmental Biology and Cancer, Albert Einstein College of Medicine, Bronx, New York 10461.
Berg
K L
KL
Pixley
F J
FJ
Angeletti
R H
RH
Stanley
E R
ER
D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000302:isolation & purification; D010449:Peptide Mapping; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine; D017027:Protein Tyrosine Phosphatases / Q000302:isolation & purification / Q000378:metabolism*; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis
D010446:Peptide Fragments; D010750:Phosphoproteins; D019000:Phosphotyrosine; D014443:Tyrosine; D016173:Macrophage Colony-Stimulating Factor; D017027:Protein Tyrosine Phosphatases