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T-cell receptor complex is essential for Fas signal transduction.

ABSTRACT: The Fas receptor (also known as CD95 and APO-1) is a member of the tumor necrosis factor alpha-family of death receptors that mediate T-cell responses. Here, we show that Fas receptor signaling requires a functional T-cell receptor (TCR) complex. Fas receptor directly binds to and activates TCR components in a stimulus-dependent manner. Fas receptor stimulation does not activate canonical downstream TCR pathways, but instead the TCR complex is required specifically for Fas-mediated calcium release. Importantly, null mutations in Lck, ZAP70, and the TCR alpha- and beta-chains abrogate Fas signaling. Our results reveal a direct role for the TCR complex in mediating Fas-specific signaling events critical for T-cell homeostasis.

SUBMITTER: Akimzhanov AM

PROVIDER: S-EPMC2930531 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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T-cell receptor complex is essential for Fas signal transduction.

Akimzhanov Askar M AM Wang Xinmin X Sun Jiaren J Boehning Darren D

Proceedings of the National Academy of Sciences of the United States of America 20100809 34

The Fas receptor (also known as CD95 and APO-1) is a member of the tumor necrosis factor alpha-family of death receptors that mediate T-cell responses. Here, we show that Fas receptor signaling requires a functional T-cell receptor (TCR) complex. Fas receptor directly binds to and activates TCR components in a stimulus-dependent manner. Fas receptor stimulation does not activate canonical downstream TCR pathways, but instead the TCR complex is required specifically for Fas-mediated calcium relea ...[more]

PMID: 20696918

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