title: Two forms of loops generate the chromatin conformation of the immunoglobulin heavy-chain gene locus.
abstract: The immunoglobulin heavy-chain (IgH) gene locus undergoes radial repositioning within the nucleus and locus contraction in preparation for gene recombination. We demonstrate that IgH locus conformation involves two levels of chromosomal compaction. At the first level, the locus folds into several multilooped domains. One such domain at the 3' end of the locus requires an enhancer, Eμ; two other domains at the 5' end are Eμ independent. At the second level, these domains are brought into spatial proximity by Eμ-dependent interactions with specific sites within the V(H) region. Eμ is also required for radial repositioning of IgH alleles, indicating its essential role in large-scale chromosomal movements in developing lymphocytes. Our observations provide a comprehensive view of the conformation of IgH alleles in pro-B cells and the mechanisms by which it is established.
authors: Gene Regulation Section, Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore, MD 21224, USA.
authors: Changying
authors: C
authors: Guo
authors: Tatiana
authors: T
authors: Gerasimova
authors: Haiping
authors: H
authors: Hao
authors: Irina
authors: I
authors: Ivanova
authors: Tirtha
authors: T
authors: Chakraborty
authors: Roza
authors: R
authors: Selimyan
authors: Eugene M
authors: EM
authors: Oltz
authors: Ranjan
authors: R
authors: Sen
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism*; D000076246:CCCTC-Binding Factor; D002467:Cell Nucleus / Q000235:genetics*; D002843:Chromatin / Q000737:chemistry*; D004742:Enhancer Elements, Genetic; D050438:Genes, Immunoglobulin Heavy Chain; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007135:Immunoglobulin Variable Region; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D012097:Repressor Proteins / Q000378:metabolism; D060152:V(D)J Recombination; D050986:YY1 Transcription Factor / Q000378:metabolism
chemical_list: D000076246:CCCTC-Binding Factor; D002843:Chromatin; C000619698:Ctcf protein, mouse; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D012097:Repressor Proteins; D050986:YY1 Transcription Factor; C494699:Yy1 protein, mouse