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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, E?; two other domains at the 5' end are E? independent. At the second level, these domains are brought into spatial proximity by E?-dependent interactions with specific sites within the V(H) region. E? 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.

SUBMITTER: Guo C

PROVIDER: S-EPMC3685183 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Two forms of loops generate the chromatin conformation of the immunoglobulin heavy-chain gene locus.

Guo Changying C Gerasimova Tatiana T Hao Haiping H Ivanova Irina I Chakraborty Tirtha T Selimyan Roza R Oltz Eugene M EM Sen Ranjan R

Cell 20111006 2

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 ...[more]

PMID: 21982154

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