Deletion of β-catenin impairs T cell development

T cells encounter two main checkpoints during development in the thymus. These checkpoints are critically dependent on signals derived from the thymic microenvironment as well as from the pre-T cell receptor (pre-TCR) and the αβ TCR. Here we show that T cell-specific deletion of β-catenin impaired T cell development at the β-selection checkpoint, leading to a substantial decrease in splenic T cells. In addition, β-catenin also seemed to be a target of TCR-CD3 signals in thymocytes and mature T cells. These data indicate that β-catenin-mediated signals are required for normal T cell development.