Analysis of signals and functions of the chimeric human granulocyte-macrophage colony-stimulating factor receptor in BA/F3 cells and transgenic mice.
Receptors for GM-CSF, IL-3, and IL-5 are composed of two subunits: alpha, which is specific for each cytokine, and betac, which is shared by all. Although the role of betac in signal transduction has been extensively studied, the role of the alpha subunit has remained to be clarified. To analyze the role of the human (h) GM-CSF receptor alpha subunit, we constructed a chimeric receptor subunit composed of extracellular and transmembrane regions of alpha fused with the cytoplasmic region of betac, designated alpha/beta. In BA/F3 cells, chimeric receptor composed of alpha/beta,beta can transduce signals for mitogen-activated protein kinase cascade activation and proliferation in response to hGM-CSF. Although phosphorylation of Jak1 but not of Jak2 occurred with stimulation of hGM-CSF, the dominant-negative Jak2 but not the dominant-negative Jak1 suppresses c-fos promoter activation. To determine whether the chimeric receptor alpha/beta,beta is functional in vivo, we developed transgenic mice expressing the chimeric receptor alpha/beta,beta. Bone marrow cells from the transgenic mice expressing the alpha/beta,beta receptor form not only GM colonies but also various lineages of colonies in response to GM-CSF. In addition, mast cells were produced when bone marrow cells of the transgenic mouse were cultured with hGM-CSF. Thus, it appears that the cytoplasmic region of the alpha subunit is not required for hGM-CSF promoting activities, even in bone marrow cells.
Watanabe
S
S
Department of Molecular Biology, Institute of Medical Science, University of Tokyo, Tokyo, Japan. sumiko@ims.u-tokyo.ac.jp
Aoki
Y
Y
Nishijima
I
I
Xu
M
M
Arai
K
K
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects; D002452:Cell Count; D018929:Cell Culture Techniques; D002455:Cell Division / Q000235:genetics / Q000276:immunology; D002460:Cell Line; D002478:Cells, Cultured; D003433:Crosses, Genetic; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000008:administration & dosage; D006801:Humans; D007272:Injections, Intralymphatic; D007279:Injections, Subcutaneous; D047908:Intracellular Signaling Peptides and Proteins; D053613:Janus Kinase 1; D053614:Janus Kinase 2; D008747:Methylcellulose; D051379:Mice; D008809:Mice, Inbred C3H; D008822:Mice, Transgenic; D010766:Phosphorylation; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism / Q000502:physiology; D011518:Proto-Oncogene Proteins; D016187:Receptors, Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000502:physiology*; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D013950:Thymus Gland / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018909:src Homology Domains / Q000235:genetics / Q000276:immunology
D047908:Intracellular Signaling Peptides and Proteins; D011518:Proto-Oncogene Proteins; D016187:Receptors, Granulocyte-Macrophage Colony-Stimulating Factor; D011993:Recombinant Fusion Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D008747:Methylcellulose; D011505:Protein-Tyrosine Kinases; C507904:JAK1 protein, human; C507924:JAK2 protein, human; C507905:Jak1 protein, mouse; C507926:Jak2 protein, mouse; D053613:Janus Kinase 1; D053614:Janus Kinase 2; 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; C516725:Ptpn11 protein, mouse; C509248:Ptpn6 protein, mouse; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases