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Variable deletion and duplication at recombination junction ends: implication for staggered double-strand cleavage in class-switch recombination.

X Chen·K Kinoshita·T Honjo
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Abstract

Immunoglobulin class-switch recombination (CSR) gives rise to looped-out circular DNA of a cleaved S segment, which is lost eventually after cell divisions. To understand the molecular mechanism of S region cleavage during CSR, we constructed artificial CSR substrates in which inversion-type CSR takes place to retain the cleaved S segment. Sequencing analyses of recombinant clones of these substrates revealed that varying degrees of deletions and duplications exist at CSR breakpoints, suggesting the involvement of staggered cleavage of the S region in CSR. In addition, mutations frequently found near junctions showed a similar profile of base replacement to Ig somatic hypermutation. These findings suggest that single-strand tails of staggered cleavage may be repaired by error-prone DNA synthesis.

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AnimalsBase SequenceCell LineChromosome InversionDNA, ComplementaryGene DeletionGene DuplicationGenes, ImmunoglobulinHumansImmunoglobulin Class SwitchingImmunoglobulin Switch RegionImmunoglobulin mu-ChainsMiceMolecular Sequence DataNucleic Acid ConformationPoint MutationRecombination, GeneticSequence Analysis, DNAJournal ArticleResearch Support, Non-U.S. Gov't

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X Chen, K Kinoshita, T Honjo. 2001-11-20. Variable deletion and duplication at recombination junction ends: implication for staggered double-strand cleavage in class-switch recombination.. https://doi.org/10.1073/pnas.241524898

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