pubmed:abstractText |
14-3-3? regulates cytokinesis and cell cycle arrest induced by DNA damage but its role in the immune system is unknown. Using gene-targeted 14-3-3?-deficient (i.e., KO) mice, we studied the role of 14-3-3? in B-cell functions. Total numbers of B cells were reduced by spontaneous apoptosis of peripheral B cells. Upon B-cell antigen receptor engagement in vitro, KO B cells did not proliferate properly or up-regulate CD86. In response to T cell-independent antigens, KO B cells showed poor secretion of antigen-specific IgM. This deficit led to increased lethality of KO mice after vesicular stomatitis virus infection. KO B cells showed elevated total FOXO transcriptional activity but also increased FOXO1 degradation. Coimmunoprecipitation revealed that endogenous 14-3-3? protein formed a complex with FOXO1 protein. Our results suggest that 14-3-3? maintains FOXO1 at a consistent level critical for normal B-cell antigen receptor signaling and B-cell survival.
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