Constraints Contributed by Chromatin Looping Limit Recombination Targeting during Immunoglobulin Class Switch Recombination
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چکیده
منابع مشابه
S region sequence, RNA polymerase II, and histone modifications create chromatin accessibility during class switch recombination
Immunoglobulin class switch recombination is governed by long-range interactions between enhancers and germline transcript promoters to activate transcription and modulate chromatin accessibility to activation-induced cytidine deaminase (AID). However, mechanisms leading to the differential targeting of AID to switch (S) regions but not to constant (C(H)) regions remain unclear. We show that S ...
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Antibody class switching is mediated by somatic recombination between switch regions of the immunoglobulin heavy chain gene locus. Targeting of recombination to particular switch regions is strictly regulated by cytokines through the induction of switch transcripts starting 5' of the repetitive switch regions. However, switch transcription as such is not sufficient to target switch recombinatio...
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During B cell development, two somatic DNA recombination events occur at the immunoglobulin heavy chain loci: VDJ recombination and class switch recombination (CSR). VDJ recombination assembles antigen receptor genes from a pool of gene segments. CSR exchanges the μ constant region of the immunoglobulin heavy chain gene for the other isotypes (γ1, γ2a, γ2b, γ3, α or ε). In both cases, the targe...
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Antibodies are assembled by a highly orchestrated series of recombination events during B cell development. One of these events, class switch recombination, is required to produce the IgG, IgE and IgA antibody isotypes characteristic of a secondary immune response. The action of the enzyme activation induced cytidine deaminase is now known to be essential for the initiation of this recombinatio...
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Changes in chromatin structure induced by posttranslational modifications of histones are important regulators of genomic function. Phosphorylation of histone H2AX promotes DNA repair and helps maintain genomic stability. Although B cells lacking H2AX show impaired class switch recombination (CSR), the precise role of H2AX in CSR and somatic hypermutation (SHM) has not been defined. We show tha...
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