Fig. 4. V_K-J_K recombination at the Igk locus in Wapl^high and Wapl^low pro-B cells.

a V_K gene recombination analysis of ex vivo sorted Wapl^+/+ (Wapl^low; black) and Wapl^{∆P1,2/∆P1,2} (Wapl^high; green) pro-B cells, as determined by VDJ-seq experiments. The recombination frequency of each V_K gene is indicated as a percentage of all V_K-J_K rearrangement events and is shown as a mean value with SEM based on six independent VDJ-seq experiments for each pro-B cell type. The different V_K genes (horizontal axis) are aligned according to their position in the Igk locus²⁵ (Supplementary Data 1a). Statistical data were analyzed by multiple t-tests (unpaired and two-tailed) with Holm–Sidak correction; *P < 0.05, **P < 0.01, ***P < 0.001. b Hi-C contact matrices of the Igk region on chromosome 6 based on published Hi-C data of short-term cultured Wapl^+/+ and Wapl^{∆P1,2/∆P1,2} pro-B cells²⁰. The orientation and annotation of the Igk locus are shown. The resolution of the Hi-C data was 6.7 and 7.25 kb for the Wapl^+/+ and Wapl^{∆P1,2/∆P1,2} pro-B cells, respectively. c Differences in V gene recombination and long-range interactions between the Igh and Igk locus in Wapl^{∆P1,2/∆P1,2} pro-B cells, based on the data shown in Fig. 4 and published data²⁰. The loss of recombination of V_H genes upon their inversion (indicated by an asterisk) in the Igh locus was analyzed in Igh^{V8-8-inv/V8-8-inv} and Igh^{∆890/∆890} pro-B cells²⁰ and upon inversion of the entire V_H gene cluster in v-Abl immortalized pro-B cells³². Source data are provided in the Source Data file.