Loss of ZBTB24 impairs nonhomologous end-joining and class-switch recombination in patients with ICF syndrome.
Fiche publication
Date publication
novembre 2020
Journal
The Journal of experimental medicine
Auteurs
Membres identifiés du Cancéropôle Est :
Dr REINA-SAN-MARTIN Bernardo
Tous les auteurs :
Helfricht A, Thijssen PE, Rother MB, Shah RG, Du L, Takada S, Rogier M, Moritz J, IJspeert H, Stoepker C, van Ostaijen-Ten Dam MM, Heyer V, Luijsterburg MS, de Groot A, Jak R, Grootaers G, Wang J, Rao P, Vertegaal ACO, van Tol MJD, Pan-Hammarström Q, Reina-San-Martin B, Shah GM, van der Burg M, van der Maarel SM, van Attikum H
Lien Pubmed
Résumé
The autosomal recessive immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome is a genetically heterogeneous disorder. Despite the identification of the underlying gene defects, it is unclear how mutations in any of the four known ICF genes cause a primary immunodeficiency. Here we demonstrate that loss of ZBTB24 in B cells from mice and ICF2 patients affects nonhomologous end-joining (NHEJ) during immunoglobulin class-switch recombination and consequently impairs immunoglobulin production and isotype balance. Mechanistically, we found that ZBTB24 associates with poly(ADP-ribose) polymerase 1 (PARP1) and stimulates its auto-poly(ADP-ribosyl)ation. The zinc-finger in ZBTB24 binds PARP1-associated poly(ADP-ribose) chains and mediates the PARP1-dependent recruitment of ZBTB24 to DNA breaks. Moreover, through its association with poly(ADP-ribose) chains, ZBTB24 protects them from degradation by poly(ADP-ribose) glycohydrolase (PARG). This facilitates the poly(ADP-ribose)-dependent assembly of the LIG4/XRCC4 complex at DNA breaks, thereby promoting error-free NHEJ. Thus, we uncover ZBTB24 as a regulator of PARP1-dependent NHEJ and class-switch recombination, providing a molecular basis for the immunodeficiency in ICF2 syndrome.
Référence
J. Exp. Med.. 2020 Nov 2;217(11):