FIG 1.

Binding of CTCF, Rad-21, and poly(ADP-ribosyl)ated moieties at the CBS of the TCRb locus. (A) Schematic map of mouse TCRb locus showing the position of Trbv segments (V1 to V31) and the recombination center encompassing PDb1-DJCb1, PDb2-DJCb2, and Eb (green bars). The CBS selected for analysis are marked. The direction of the red flag indicates the orientation of the CBS. (B to D) ChIP-qPCR analysis to estimate the binding of CTCF, Rad-21, and poly(ADP-ribosyl)ated moieties at the CBS in DN thymocytes and ProB cells isolated from Rag1-deficient mice. In each case, the ChIP-qPCR signals were normalized to the values observed for CBS-3 of H19-ICR at the Igf2/H19 locus. Values represent the mean enrichments (plus the standard errors of the mean [SEM]) from three biological replicates. The significance of enrichment between DN and ProB cells was analyzed by using a Student t test (*, P < 0.05). Table S1 in the supplemental material provides the genomic coordinates of the analyzed CBS.