Looping out and deletion mechanism for the immunoglobulin heavy-chain class switch.
AUTOR(ES)
Jäck, H M
RESUMO
In the mouse pre-B-cell line 18-81, cells can switch production in vitro from immunoglobulin mu chain to gamma 2b chain. The gene encoding the gamma 2b chain is created by a rearrangement of the mu gene. This rearrangement always takes place within a homolog. In cells with a gamma 2b gene, most of the time the gene segment encoding the constant region of the mu chain is deleted, but often the rearrangement leads to cells that produce no immunoglobulin, and all DNA sequences are retained. The latter result is due to an inversion. Inversions exclude the unequal sister chromatid exchange model of the heavy-chain class switch. Looping out is an intermediate step in the process of generating an inversion. Our findings demonstrate that the switch rearrangement occurs by looping out and deletion.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=279817Documentos Relacionados
- Rearrangement of immunoglobulin gamma 1-chain gene and mechanism for heavy-chain class switch.
- Mutations, duplication, and deletion of recombined switch regions suggest a role for DNA replication in the immunoglobulin heavy-chain switch.
- Copy choice mechanism of immunoglobulin heavy-chain switch recombination.
- Anomalous rearrangements of the immunoglobulin heavy chain genes in human leukemias support the loop-out mechanism of class switch.
- Visualization of looping involving the immunoglobulin heavy-chain locus in developing B cells
