Recombination in the Vicinity of Insertions of Transposon Tn 5 in MYXOCOCCUS XANTHUS.
Recombination in the Vicinity of Insertions of Transposon Tn 5 in MYXOCOCCUS XANTHUS.
复制标题
黄色粘球菌中转座子 Tn 5 插入附近的重组。
作者：
E. Sodergren;Y. Cheng;L. Avery;D. Kaiser
为了检测转座子Tn5插入附近的遗传重组，在携带不同Tn5插入的黄毒杆菌菌株之间进行了转导杂交。每对1只携带卡那霉素耐药（Tn5-Km）；另一组携带四环素耐药（Tn5-Tc）。每对Tn5插入之间的距离也通过限制性内切作图测量。根据转导链计算每个重组频率对应的物理距离，并与限制图上的距离进行比较。在靠近cglB位点的一对Tn5插入位点和靠近mgl位点的另一对Tn5插入位点之间的两个距离测量之间获得了良好的对应关系。两次距离测量的一致性，观察到Tn5- km和Tn5 -Tc在同一位点的等位基因行为，以及在反向杂交中发现的相同频率的重组，表明Tn5附近的重组是正常的。
To test genetic recombination in the vicinity of insertions of the transposon Tn5, crosses were performed by transduction between M. xanthus strains carrying different insertions of Tn5. One member of each pair carried resistance to kanamycin (Tn5-Km); the other carried resistance to tetracycline (Tn5-Tc). The distance between each pair of Tn5 insertions was also measured by restriction mapping. The physical distance corresponding to each recombination frequency was calculated from the transductional linkage and compared with distance on the restriction map. A good correspondence between the two measures of distance was obtained for a pair of Tn5 insertions near the cglB locus and for another pair near the mgl locus. Correspondence between the two measurements of distance, the observed allelic behavior of Tn5-Km and Tn5 -Tc at the same locus and the finding of the same frequencies of recombinants in reciprocal crosses implied that recombination in the vicinity of Tn 5 was normal.