5C Chromatin interactions in the Igh locus in B cell progenitors

ABSTRACT: These tracks include chromatin interaction data produced using the 5C (chromatin conformation capture carbon copy) method by the Kenter Lab located at the University of Illinois College of Medicine, Chicago, IL. These tracks show looping interactions across the Igh locus using alternating forward and reverse primer design scheme. The 3C method uses formaldehyde crosslinking to covalently associate interacting chromatin segments in intact cells. The cells are then lysed and chromatin is digested with the Hind III restriction enzyme. The digested fragments are ligated under dilute conditions to promote intra-molecular ligation. A genome-wide interaction library of ligation products corresponding to all possible chromatin interactions is produced by this method. In 5C assays, over 12,000 potential ligation products specific to the Igh locus are detected by PCR using multiplexed primer pairs. These studies have revealed three conserved topological sub-domains. Each topological folds encompasses a major VH gene family. The Pax5 transcription factor organizes the topological sub-domain that spans the VHJ558 gene family. In the absence of Pax5, the distal J558 VH genes fail to associate with the proximal VH genes, thus providing an explanation for reduced VHJ558 gene rearrangements in Pax5-deficient pro-B cells. We propose that Igh locus contraction is the cumulative effect of several independently controlled chromatin sub-domains that provide the structural infrastructure to coordinate optimal antigen receptor assembly (Montefiori et al. 2015). We also note that the configuration of the 3’ end of the Igh locus spanning the CH region genes assumes a developmental stage specific configuration in pro-B cells that appreas to skew class switch recombination to specific isotypes. This 3D spatial configuration is lost in resting splenic B cells that are capable of class switch recombination to all isotypes (Kumar et al. 2013).

ORGANISM(S): Mus musculus

PROVIDER: GSE76086 | GEO | 2016/02/02

SECONDARY ACCESSION(S): PRJNA306173

REPOSITORIES: GEO