The anti-apoptotic activities of Rel and RelA required during B-cell maturation involve the regulation of Bcl-2 expression

✍ Scribed by Grossmann, M.

• Book ID: 111747676
• Publisher: Nature Publishing Group
• Year: 2000
• Tongue: English
• Weight: 516 KB
• Volume: 19
• Category: Article
• ISSN: 0261-4189
• DOI: 10.1093/emboj/19.23.6351

✦ Synopsis

Rel and RelA, individually dispensable for lymphopoiesis, serve unique functions in activated B and T cells. Here their combined roles in lymphocyte development were examined in chimeric mice repopulated with c-rel(-/-) rela(-/-) fetal liver hemopoietic stem cells. Mice engrafted with double-mutant cells lacked mature IgM(lo)IgD(hi) B cells, and numbers of peripheral CD4(+) and CD8(+) T cells were markedly reduced. The absence of mature B cells was associated with impaired survival that coincided with reduced expression of bcl-2 and A1. bcl-2 transgene expression not only prevented apoptosis and increased peripheral B-cell numbers, but also induced further maturation to an IgM(lo)IgD(hi) phenotype. In contrast, the survival of double-mutant T cells was normal and the bcl-2 transgene could not rectify the peripheral T-cell deficit. These findings indicate that Rel and RelA serve essential, albeit redundant, functions during the later antigen-independent stages of B- and T-cell maturation, with these transcription factors promoting the survival of peripheral B cells in part by upregulating Bcl-2.