Gu H, Zou Y R, Rajewsky K
Institute for Genetics, University of Cologne, Federal Republic of Germany.
Cell. 1993 Jun 18;73(6):1155-64. doi: 10.1016/0092-8674(93)90644-6.
We have employed a method based on the Cre-loxP recombination system of bacteriophage P1 to generate a mouse strain in which the JH segments and the intron enhancer in the IgH locus are deleted. By analysis of immunoglobulin isotype switch recombination in heterozygous mutant B cells activated by lipopolysaccharide plus interleukin-4, we show that, on the mutant chromosome, switch recombination at the mu gene switch region is strongly suppressed, whereas the switch region of the gamma 1 gene is efficiently rearranged. These data demonstrate an independent control of switch recombination at individual switch regions and suggest that, in the process of switch recombination, the alignment of the recombining strands occurs independently of and probably after the introduction of double-strand breaks into the switch regions involved.
我们采用了一种基于噬菌体P1的Cre-loxP重组系统的方法，来生成一种小鼠品系，其中IgH基因座中的JH片段和内含子增强子被删除。通过分析由脂多糖加白细胞介素-4激活的杂合突变B细胞中的免疫球蛋白同种型转换重组，我们发现，在突变染色体上，μ基因转换区的转换重组受到强烈抑制，而γ1基因的转换区则有效地进行了重排。这些数据证明了各个转换区的转换重组是独立控制的，并表明，在转换重组过程中，重组链的排列独立于并可能在涉及的转换区引入双链断裂之后发生。
