Engels W R, Preston C R, Johnson-Schlitz D M
Genetics Department, University of Wisconsin, Madison 53706.
Science. 1994 Mar 18;263(5153):1623-5. doi: 10.1126/science.8128250.
P element-induced chromosome breakage on the X chromosome of Drosophila melanogaster was repaired six times more frequently when a homologous template was located anywhere on the X chromosome rather than on an autosome. Cis-trans comparisons confirmed that recombinational repair was more frequent when the interacting sequences were physically connected. These results suggest that the search for homology between the broken ends and a matching template sequence occurs preferentially in the cis configuration. This cis advantage operates over more than 15 megabases of DNA.
在黑腹果蝇的X染色体上，当同源模板位于X染色体的任何位置而非常染色体上时，P因子诱导的染色体断裂修复频率高出六倍。顺反比较证实，当相互作用的序列物理连接时，重组修复更为频繁。这些结果表明，断裂末端与匹配模板序列之间的同源性搜索优先以顺式构型发生。这种顺式优势作用于超过15兆碱基的DNA区域。
