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LAB: A new membrane-associated adaptor molecule in B cell activation

Nature Immunologyvolume 4pages117123 (2003) | Download Citation



The adaptor molecule, linker for activation of T cells (LAT), is essential in T cell activation and development; a similar molecule in B cells has not yet been identified. Here, we report the identification of a new adaptor protein, linker for activation of B cells (LAB). Like LAT, LAB was localized to lipid rafts. Upon activation via the B cell receptor (BCR), LAB was phosphorylated and interacted with the adaptor protein Grb2. Decreased LAB expression led to a reduction in BCR-mediated calcium flux and Erk activation. LAB rescued thymocyte development but not normal T cell activation in LAT−/− mice. Our data suggest that LAB links BCR engagement to downstream signaling pathways.

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We thank the Duke University Cancer Center Flow Cytometry and Sequencing facilities. This work is supported by National Institutes of Health Grant 1R01 AI48674-01.

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  1. Department of Immunology, Duke University Medical Center, Durham, 27710, NC, USA

    • Erin Janssen
    • , Minghua Zhu
    • , Surapong Koonpaew
    •  & Weiguo Zhang
  2. Genetics Division of Department of Medicine, Harvard Medical School and Brigham & Women's Hospital, Boston, 02115, MA, USA

    • Weijia Zhang


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Correspondence to Weiguo Zhang.

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