Galjart, N.

locus region igk locus pre-b figure pre-b cells interaction 1-cre recombination enhancer segment transcription vk gene segments vh 81x ficient expression pro-b element analysis immunity usage control 220+cd germline ctcf-de rearrangement absence igk enhancer interactions b cell development germline transcription vk region b cells fraction chromatin vk usage allele 3 c-seq experiments -/- intracellular number stage c-seq chain ctcf occupancy level pre-b cell stage proliferation speci factor sis element protein vh segments october genotype vk genes differentiation immunoglobulin deletion elsevier ª2011 sequence flow cytometric analysis development b cell lineage igh locus contraction pro-b cells b 220+cd receptor rt-pcr ctcf sites vk gene usage sequencing jk germline transcription viewpoint immunol nding lineage identi igh locus ctcf-binding sites