title: Inactivation of c-Cbl reverses neonatal lethality and T cell developmental arrest of SLP-76-deficient mice.
abstract: c-Cbl is an adaptor protein that negatively regulates signal transduction events involved in thymic-positive selection. To further characterize the function of c-Cbl in T cell development, we analyzed the effect of c-Cbl inactivation in mice deficient in the scaffolding molecule SLP-76. SLP-76-deficient mice show a high frequency of neonatal lethality; and in surviving mice, T cell development is blocked at the DN3 stage. Inactivation of c-cbl completely reversed the neonatal lethality seen in SLP-76-deficient mice and partially reversed the T cell development arrest in these mice. SLP-76(-/-) Cbl(-/-) mice exhibited marked expansion of polarized T helper type (Th)1 and Th2 cell peripheral CD4(+) T cells, lymphoid infiltrates of parenchymal organs, and premature death. This rescue of T cell development is T cell receptor dependent because it does not occur in recombination activating gene 2(-/-) SLP-76(-/-) Cbl(-/-) triple knockout mice. Analysis of the signal transduction properties of SLP-76(-/-) Cbl(-/-) T cells reveals a novel SLP-76- and linker for activation of T cells-independent pathway of extracellular signal-regulated kinase activation, which is normally down-regulated by c-Cbl.
authors.affiliation: Experimental Immunology Branch, Building 10, Room 4B36, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. chiangj@mail.nih.gov
authors.forename: Y Jeffrey
authors.initials: YJ
authors.lastname: Chiang
authors.forename: Connie L
authors.initials: CL
authors.lastname: Sommers
authors.forename: Martha S
authors.initials: MS
authors.lastname: Jordan
authors.forename: Hua
authors.initials: H
authors.lastname: Gu
authors.forename: Lawrence E
authors.initials: LE
authors.lastname: Samelson
authors.forename: Gary A
authors.initials: GA
authors.lastname: Koretzky
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Hodes
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D000831:Animals, Newborn; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002469:Cell Separation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005434:Flow Cytometry; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism; D008168:Lung / Q000166:cytology / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D050721:Proto-Oncogene Proteins c-cbl; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D013154:Spleen / Q000166:cytology; D015996:Survival Rate; D016176:T-Lymphocyte Subsets / Q000502:physiology; D013601:T-Lymphocytes / Q000502:physiology*; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D007376:Interleukin-2; C491734:Lat protein, mouse; D008565:Membrane Proteins; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; C499308:Rag2 protein, mouse; D011948:Receptors, Antigen, T-Cell; C092947:SLP-76 signal Transducing adaptor proteins; C064655:V(D)J recombination activating protein 2; D015847:Interleukin-4; D007371:Interferon-gamma; D050721:Proto-Oncogene Proteins c-cbl; D044767:Ubiquitin-Protein Ligases; C067419:CBL protein, human; C493849:Cbl protein, mouse