Xu Z, Fulop Z, Wu G, Pone EJ, Zhang J, Mai T, Thomas LM, Al-Qahtani A, White CA, Park SR, Steinacker P, Li Z, Yates J, Herron B, Otto M, Zan H, Fu H, Casali P. 14-3-3 adaptor proteins recruit AID to 5'-AGCT-3'-rich switch regions for class switch recombination.
Nat Struct Mol Biol 2010;
17:1124-35. [PMID:
20729863 PMCID:
PMC3645988 DOI:
10.1038/nsmb.1884]
[Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 07/01/2010] [Indexed: 01/09/2023]
Abstract
Class switch DNA recombination (CSR) is the mechanism that diversifies the biological effector functions of antibodies. Activation-induced cytidine deaminase (AID), a key CSR player, targets IgH switch (S) regions, which contain 5′-AGCT-3′ repeats in their core. How AID is recruited to S regions remains unclear. Here we show that 14-3-3 adaptor proteins play an important role in CSR. 14-3-3 proteins specifically bind 5′-AGCT-3′ repeats, are upregulated in B cells undergoing CSR and are recruited together with AID to the S regions involved in CSR events (Sμ→Sγ1, Sμ→Sγ3 or Sμ→Sα). Moreover, blocking 14-3-3 by difopein, deficiency in 14-3-3γ or expression of a dominant negative 14-3-3σ mutant impaired recruitment of AID to S regions and decreased CSR. Finally, 14-3-3 proteins interact directly with AID and enhance AID-mediated in vitro DNA deamination, further emphasizing the important role of these adaptors in CSR.
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