RAG-2 expression is not essential for chicken immunoglobulin gene conversion.

AUTOR(ES)

Takeda, S

RESUMO

Chicken B cells diversify their immunoglobulin genes by gene conversion in the bursa of Fabricius. The avian leukosis virus-induced B-cell line DT40 continues to diversify its immunoglobulin light chain locus by gene conversion during in vitro passage. Since a variable(diversity)joining recombination-activating gene, RAG-2, is specifically expressed in chicken B cells undergoing immunoglobulin gene conversion, it has been suggested that RAG-2 may be involved in the immunoglobulin gene conversion process. We previously reported high ratios of targeted to random integration after transfection of genomic DNA constructs into DT40. This allows us to easily investigate the function of a gene product by gene disruption. We show here that subclones of DT40 maintain the ability to diversify their immunoglobulin light chain locus by gene conversion even after both copies of the RAG-2 coding regions are deleted. These results demonstrate that the RAG-2 product is not required for gene conversion activity in the immunoglobulin light chain locus.

Documentos Relacionados

• RAG-1 and RAG-2 are not sufficient to direct all phases of immunoglobulin gene rearrangement in pre-B-cell lines.
• rag-1 and rag-2 are components of a high-molecular-weight complex, and association of rag-2 with this complex is rag-1 dependent.
• Regulation of RAG-2 protein expression in avian thymocytes.
• Polymorphism in immunoglobulin heavy chains suggesting gene conversion.
• Two mechanisms for directional gene conversion.