Nature Immunology
2, 556 - 563 (2001)
doi:10.1038/88765
Antigen-induced translocation of PKC- to membrane rafts is required for T cell activationKun Bi1, Yoshihiko Tanaka1, Nolwenn Coudronniere1, Katsuji Sugie2, Sooji Hong1, Marianne J. B. van Stipdonk3
& Amnon Altman11
Division of Cell Biology, La Jolla Institute for Allergy and Immunology, 10355 Science Center Drive, San Diego, CA 92121, USA. 2
Division of Immunochemistry, La Jolla Institute for Allergy and Immunology, 10355 Science Center Drive, San Diego, CA 92121, USA. 3
Division of Immune Regulation, La Jolla Institute for Allergy and Immunology, 10355 Science Center Drive, San Diego, CA 92121, USA.
Correspondence should be addressed to Amnon Altman amnon@liai.orgProtein kinase C- (PKC-) is essential for mature T cell activation; however, the mechanism by which it is recruited to the TCR signaling machinery is unknown. Here we show that T cell stimulation by antibodies or peptide−major histocompatibility complex (MHC) induces translocation of PKC- to membrane lipid rafts, which localize to the immunological synapse. Raft translocation was mediated by the PKC- regulatory domain and required Lck but not ZAP-70. In addition, PKC- was associated with Lck in the rafts. An isolated PKC- catalytic fragment did not partition into rafts or activate the transcription factor NF- B, although addition of a Lck-derived raft-localization sequence restored these functions. Thus, physiological T cell activation translocates PKC- to rafts, which localize to the T cell synapse; this PKC- translocation is important for its function.
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