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A genetically selective inhibitor demonstrates a function for the kinase Zap70 in regulatory T cells independent of its catalytic activity.

ABSTRACT: To investigate the role of the kinase Zap70 in T cells, we generated mice expressing a Zap70 mutant whose catalytic activity can be selectively blocked by a small-molecule inhibitor. We found that conventional naive, effector and memory T cells were dependent on the kinase activity of Zap70 for their activation, which demonstrated a nonredundant role for Zap70 in signals induced by the T cell antigen receptor (TCR). In contrast, the catalytic activity of Zap70 was not required for activation of the GTPase Rap1 and inside-out signals that promote integrin adhesion. This Zap70 kinase-independent pathway was sufficient for the suppressive activity of regulatory T cells (T(reg) cells), which was unperturbed by inhibition of the catalytic activity of Zap70. Our results indicate Zap70 is a likely therapeutic target.

SUBMITTER: Au-Yeung BB

PROVIDER: S-EPMC3711183 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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A genetically selective inhibitor demonstrates a function for the kinase Zap70 in regulatory T cells independent of its catalytic activity.

Au-Yeung Byron B BB Levin Susan E SE Zhang Chao C Hsu Lih-Yun LY Cheng Debra A DA Killeen Nigel N Shokat Kevan M KM Weiss Arthur A

Nature immunology 20101031 12

To investigate the role of the kinase Zap70 in T cells, we generated mice expressing a Zap70 mutant whose catalytic activity can be selectively blocked by a small-molecule inhibitor. We found that conventional naive, effector and memory T cells were dependent on the kinase activity of Zap70 for their activation, which demonstrated a nonredundant role for Zap70 in signals induced by the T cell antigen receptor (TCR). In contrast, the catalytic activity of Zap70 was not required for activation of ...[more]

PMID: 21037577

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