Molecular analysis of γ1 γ3 and α class switch recombination junctions in APOBEC3-deficient mice using high-throughput sequencing

摘要

CSR in APOBEC3-deficient mice. a IgG1, IgG3, and IgA CSR in APOBEC3-deficient and wt mice. B-splenocytes were cultured with LPS for 4 days with (IgG1 CSR) or without (IgG3 CSR) IL-4 or TGFβ (IgA CSR). Cells gated on B220+ and/or CD138+ cells were labeled with anti-IgM, anti-IgG3, anti-IgG1, and anti-IgA antibodies. The mean ± SEM of 4 experiments is reported for each isotype. No significant differences were found (Mann–Whitney U-test). b Structural profiles of Sμ–Sγ3, Sμ–Sγ1, and Sμ–Sα junctions in APOBEC3-deficient, hAPOBEC3A, hAPOBEC3G, and wt mice. Junctions are classified as follows: junction with insertion, blunt junction, junction with microhomology (<4 bp) or large homology (≥4 bp). The results (mean ± SEM) from two to seven mice for each isotype are pooled. No significant differences were found (chi-squared test) compared to wt mice. c Breakpoint locations in Sμ–Sγ1, Sμ–Sγ3 and Sμ–Sα junctions in wt and APOBEC3-deficient mice (same junctions as in b). d Breakpoints in mouse APOBEC3 TYC hotspot motifs in Sμ, Sγ1, Sγ3, and Sα junctions (same junctions as in b). The theoretical levels of TYC breakpoints are highlighted. e Breakpoints in mouse AID WRCY hotspot motifs in Sμ, Sγ1, Sγ3, and Sα junctions (same junctions as in b). The theoretical levels of AID breakpoints are highlighted