PMID- 10080542 OWN - NLM STAT- MEDLINE DCOM- 19990401 LR - 20190516 IS - 0741-5400 (Print) IS - 0741-5400 (Linking) VI - 65 IP - 3 DP - 1999 Mar TI - Flt3 signaling involves tyrosyl-phosphorylation of SHP-2 and SHIP and their association with Grb2 and Shc in Baf3/Flt3 cells. PG - 372-80 AB - Flt3 ligand (FL) is an early-acting potent co-stimulatory cytokine that regulates proliferation and differentiation of a number of blood cell lineages. Its receptor Flt3/Flk2 belongs to class III receptor tyrosine kinases that also include the receptors for colony-stimulating factor 1, Steel factor, and platelet-derived growth factor. Using CSF-1 receptor/Flt3 chimeras, two groups have characterized some of the post-receptor signaling events and substrate specificity of murine Flt3 receptor. However, there are few studies on the signaling pathway through human Flt3. We examined human Flt3 signaling pathways in a murine IL-3-dependent hematopoietic cell line Baf3, which stably expresses full-length human Flt3 receptor. This subline proliferates in response to human FL. Like the chimeric murine Flt3, human Flt3 undergoes autophosphorylation, associates with Grb2, and leads to tyrosine phosphorylation of Shc on ligand binding. We found that SHP-2, but not SHP-1, is tyrosine-phosphorylated by FL stimulation. SHP-2 does not associate with Flt3, but binds directly to Grb2. SHIP is also tyrosine-phosphorylated and associates with Shc after FL simulation. We further examined the downstream signaling pathway. FL transiently activates MAP kinase. This activation could be blocked by PD98059, a specific MEK inhibitor. PD98059 also blocked cell proliferation in response to FL. These results demonstrate that SHP-2 and SHIP are important components in the human Flt3 signaling pathway and suggest that SHP-2 and SHIP, by forming complexes with adapter proteins Grb2 and Shc, may modulate MAP kinase activation, which may be necessary for the mitogenic signaling of Flt3. FAU - Zhang, S AU - Zhang S AD - Department of Microbiology/Immunology, and the Walther Oncology Center, Indiana University School of Medicine, Indianapolis 46202-5254, USA. FAU - Mantel, C AU - Mantel C FAU - Broxmeyer, H E AU - Broxmeyer HE LA - eng GR - P01 HL 53586/HL/NHLBI NIH HHS/United States GR - R01 HL 54037/HL/NHLBI NIH HHS/United States GR - R01 HL 56416/HL/NHLBI NIH HHS/United States PT - Journal Article PT - Research Support, U.S. Gov't, P.H.S. PL - United States TA - J Leukoc Biol JT - Journal of leukocyte biology JID - 8405628 RN - 0 (Adaptor Proteins, Signal Transducing) RN - 0 (Adaptor Proteins, Vesicular Transport) RN - 0 (GRB2 Adaptor Protein) RN - 0 (GRB2 protein, human) RN - 0 (Grb2 protein, mouse) RN - 0 (Intracellular Signaling Peptides and Proteins) RN - 0 (Membrane Proteins) RN - 0 (Proteins) RN - 0 (Proto-Oncogene Proteins) RN - 0 (SHC1 protein, human) RN - 0 (Shc Signaling Adaptor Proteins) RN - 0 (Shc1 protein, mouse) RN - 0 (Src Homology 2 Domain-Containing, Transforming Protein 1) RN - 0 (flt3 ligand protein) RN - 42HK56048U (Tyrosine) RN - EC 2.7.10.1 (FLT3 protein, human) RN - EC 2.7.10.1 (Flt3 protein, mouse) RN - EC 2.7.10.1 (Receptor Protein-Tyrosine Kinases) RN - EC 2.7.10.1 (fms-Like Tyrosine Kinase 3) RN - EC 3.1.3.2 (Phosphoric Monoester Hydrolases) RN - EC 3.1.3.48 (PTPN11 protein, human) RN - EC 3.1.3.48 (PTPN6 protein, human) RN - EC 3.1.3.48 (Protein Tyrosine Phosphatase, Non-Receptor Type 11) RN - EC 3.1.3.48 (Protein Tyrosine Phosphatase, Non-Receptor Type 6) RN - EC 3.1.3.48 (Protein Tyrosine Phosphatases) RN - EC 3.1.3.48 (Ptpn11 protein, mouse) RN - EC 3.1.3.48 (Ptpn6 protein, mouse) RN - EC 3.1.3.48 (SH2 Domain-Containing Protein Tyrosine Phosphatases) RN - EC 3.1.3.86 (INPPL1 protein, human) RN - EC 3.1.3.86 (Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases) SB - IM MH - *Adaptor Proteins, Signal Transducing MH - *Adaptor Proteins, Vesicular Transport MH - Animals MH - Cell Line MH - GRB2 Adaptor Protein MH - Humans MH - Intracellular Signaling Peptides and Proteins MH - Membrane Proteins/*metabolism MH - Mice MH - Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases MH - Phosphoric Monoester Hydrolases/*metabolism MH - Phosphorylation MH - Protein Tyrosine Phosphatase, Non-Receptor Type 11 MH - Protein Tyrosine Phosphatase, Non-Receptor Type 6 MH - Protein Tyrosine Phosphatases/*metabolism MH - Proteins/*metabolism MH - Proto-Oncogene Proteins/*metabolism MH - Receptor Protein-Tyrosine Kinases/*metabolism MH - SH2 Domain-Containing Protein Tyrosine Phosphatases MH - Shc Signaling Adaptor Proteins MH - *Signal Transduction MH - Src Homology 2 Domain-Containing, Transforming Protein 1 MH - Transfection MH - Tyrosine/metabolism MH - fms-Like Tyrosine Kinase 3 MH - src Homology Domains EDAT- 1999/03/18 00:00 MHDA- 1999/03/18 00:01 CRDT- 1999/03/18 00:00 PHST- 1999/03/18 00:00 [pubmed] PHST- 1999/03/18 00:01 [medline] PHST- 1999/03/18 00:00 [entrez] AID - 10.1002/jlb.65.3.372 [doi] PST - ppublish SO - J Leukoc Biol. 1999 Mar;65(3):372-80. doi: 10.1002/jlb.65.3.372.