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RIBP, a novel Rlk/Txk- and itk-binding adaptor protein that regulates T cell activation.

ABSTRACT: A novel T cell-specific adaptor protein, RIBP, was identified based on its ability to bind Rlk/Txk in a yeast two-hybrid screen of a mouse T cell lymphoma library. RIBP was also found to interact with a related member of the Tec family of tyrosine kinases, Itk. Expression of RIBP is restricted to T and natural killer cells and is upregulated substantially after T cell activation. RIBP-disrupted knockout mice displayed apparently normal T cell development. However, proliferation of RIBP-deficient T cells in response to T cell receptor (TCR)-mediated activation was significantly impaired. Furthermore, these activated T cells were defective in the production of interleukin (IL)-2 and interferon gamma, but not IL-4. These data suggest that RIBP plays an important role in TCR-mediated signal transduction pathways and that its binding to Itk and Rlk/Txk may regulate T cell differentiation.

SUBMITTER: Rajagopal K

PROVIDER: S-EPMC2195727 | biostudies-literature | 1999 Dec

REPOSITORIES: biostudies-literature

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RIBP, a novel Rlk/Txk- and itk-binding adaptor protein that regulates T cell activation.

Rajagopal K K Sommers C L CL Decker D C DC Mitchell E O EO Korthauer U U Sperling A I AI Kozak C A CA Love P E PE Bluestone J A JA

The Journal of experimental medicine 19991201 11

A novel T cell-specific adaptor protein, RIBP, was identified based on its ability to bind Rlk/Txk in a yeast two-hybrid screen of a mouse T cell lymphoma library. RIBP was also found to interact with a related member of the Tec family of tyrosine kinases, Itk. Expression of RIBP is restricted to T and natural killer cells and is upregulated substantially after T cell activation. RIBP-disrupted knockout mice displayed apparently normal T cell development. However, proliferation of RIBP-deficient ...[more]

PMID: 10587356

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