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bioRxiv · 10.1101/580191

The actin-capping protein alpha-adducin is required for T-cell costimulation

Thauland, T. J.·Butte, M. J.
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Abstract

Alpha-adducin (Add1) is a critical component of the actin-spectrin network in erythrocytes, acting to cap the fast-growing, barbed ends of actin filaments, and recruiting spectrin to these junctions. Add1 is highly expressed in T cells, but its role in T-cell activation has not been examined. Using a conditional knockout model, we show that Add1 is necessary for complete activation of CD4+ T cells in response to low levels of antigen but is dispensable for CD8+ T cell activation and response to infection. Surprisingly, costimulatory signals through CD28 were completely abrogated in the absence of Add1. This study is the first to examine the role of actin-capping in T cells, and it reveals a previously unappreciated role for the actin cytoskeleton in regulating costimulation.

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Thauland, T. J., Butte, M. J.. 2019-03-16. The actin-capping protein alpha-adducin is required for T-cell costimulation. https://doi.org/10.1101/580191

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