Identification and characterization of leukocyte-associated Ig-like receptor-1 as a major anchor protein of tyrosine phosphatase SHP-1 in hematopoietic cells.
SHP-1, an SH2 domain-containing tyrosine phosphatase, has a crucial role in hematopoiesis. Here we report that SHP-1 is associated with two major tyrosine-phosphorylated proteins in hematopoietic cells treated with the tyrosine phosphatase inhibitor, pervanadate. One of the proteins corresponds to leukocyte-associated Ig-like receptor-1 (LAIR-1), a recently cloned transmembrane protein. Molecular cloning revealed four isoforms of the protein. LAIR-1 is hyper-phosphorylated on tyrosyl residues in cells overexpressing a catalytically inactive mutant form of SHP-1 as well as in pervanadate-treated cells. An antibody against the extracellular domain of the protein also induced its tyrosine phosphorylation. Tyrosine-phosphorylated LAIR-1 specifically interacts with SHP-1 but not with SHP-2, a structurally related tyrosine phosphatase. Using site-specific mutagenesis, we demonstrated that Tyr(233) and Tyr(263), each embedded in an immunoreceptor tyrosine-based inhibitory motif, are responsible for tyrosine phosphorylation of LAIR-1 and recruitment of SHP-1. Both tyrosyl residues are required for SHP-1 binding. Protein kinases responsible for tyrosine phosphorylation of LAIR-1 may belong to the Src family since PP1, a Src family kinase inhibitor, significantly inhibited its phosphorylation. As a major binding protein of SHP-1 on the plasma membrane, LAIR-1 may play an important role in hematopoietic cell signaling.
Xu
M j
Mj
Hematology/Oncology Division, Department of Medicine, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37232-6305, USA.
Zhao
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Zhao
Z J
ZJ
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D001665:Binding Sites; D002460:Cell Line; D003001:Cloning, Molecular; D018922:HL-60 Cells; D006410:Hematopoiesis; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D019169:Jurkat Cells; D007668:Kidney; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000737:chemistry* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases; D014162:Transfection; D014443:Tyrosine; D018909:src Homology Domains
D047908:Intracellular Signaling Peptides and Proteins; D011971:Receptors, Immunologic; D011994:Recombinant Proteins; C108073:leukocyte-associated immunoglobulin-like receptor 1; D014443:Tyrosine; C516724:PTPN11 protein, human; C509249:PTPN6 protein, human; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases