Unique repetitive nucleic acid structures mirror switch regions in the human IgH locus - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Biochimie Année : 2023

Unique repetitive nucleic acid structures mirror switch regions in the human IgH locus

Résumé

Immunoglobulin (Ig) genes carry the unique ability to be reshaped in peripheral B lymphocytes after these cells encounter a specific antigen. B cells can then further improve their affinity, acquire new functions as memory cells and eventually end up as antibody-secreting cells. Ig class switching is an important change that occurs in this context, thanks to local DNA lesions initiated by the enzyme activation-induced deaminase (AID). Several cis-acting elements of the Ig heavy (IgH) chain locus make it accessible to the AID-mediated lesions that promote class switch recombination (CSR). DNA repeats, with a non-template strand rich in G-quadruplexes (G4)-DNA, are prominent cis-targets of AID and define the so-called "switch" (S) regions specifically targeted for CSR. By analyzing the structure of the human IgH locus, we uncover that abundant DNA repeats, some with a putative G4-rich template strand, are additionally present in downstream portions of the IgH coding genes. These like-S (LS) regions stand as 3’ mirror-images of S regions and also show analogies to some previously reported repeats associated with the IgH locus 3’ super-enhancer. A regulatory role of LS repeats is strongly suggested by their specific localization close to exons encoding the membrane form of Ig molecules, and by their conservation during mammalian evolution.

Dates et versions

hal-04212710 , version 1 (20-09-2023)

Identifiants

Citer

Ophelie Deze, Delfina Ordanoska, Delphine Rossille, Emma Miglierina, Brice Laffleur, et al.. Unique repetitive nucleic acid structures mirror switch regions in the human IgH locus. Biochimie, 2023, 214, pp.167-175. ⟨10.1016/j.biochi.2023.08.017⟩. ⟨hal-04212710⟩
12 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More