MOLECULAR ANALYSIS OF THE OM MUTATOR IN DROSOPHILA ANANASSAE

辛顿描述了一种不寻常的突变体，他推测它是 一种具有(以前)新特性的转置元件Tom： 元素只能通过其对眼睛的影响来检测表型 21个非多效性、非剂量复合、非随机基因座的形态。 因为在一种自发性灼伤突变中恢复了SN9G 眼球形态(Om)突变系衍生，Om(LD)9G，是可能的 来调查他的猜测。D.黑猩猩烧灼，sn，dna探针 被用来分离和回收一个被D anansae烧灼的基因。一种比较 SN9G和野生型烧灼的限制性内切酶图谱包含6.5kb的插入 作为诱变子效应的元素点。总共186个 对来自4个X连锁Om基因座的重组系进行了检测。80个是Om和 106个是非Om；在所有情况下都是原位杂交信号，当 在多线上的适当位置发现了带有Sn9G插入物的探针 染色体。连接完成，表明SN9G插入物是 与Om突变体定位的序列同源。 对几个分离的Tom元素克隆的初步分析表明 一种相当保守的结构，是类Copia元素的典型特征。DNA序列 对Sn9G和Om(LD)9G处的TOM的分析表明，在 也是复制物样元素的特征的末端。继续前进 对几个OM(LD)突变的Southern杂交研究表明，其中一些是 由于插入了单个TOM，其他的似乎是由于多个 复制品和其他复制品显示，即刻附近没有明显的变化。 Om(Ld)9g.TOM元素和Om的进一步研究 突变应该能让我们深入了解这种 不寻常的突变过程。

Hinton described an unusual mutator in D. ananassae which he speculated was a transposable element, tom, with (previously) novel properties: the element could only be detected phenotypically by its effect on eye morphology at 21 non-pleiotropic, non-dosage compensted, non-random loci. Because of the recovery of a spontaneous singed mutation, sn9g, in an ocullar morphology (Om) mutant line derivative, Om(lD)9g, it was possible to investigate his speculation. D. melanogaster singed, sn, DNA probes were used to isolate and recover a D. ananassae singed gene. A comparison of the sn9g and wild type singed restriction map implicated a 6.5 kb insert as the element responsible for the mutator effect. A total of 186 recombinant lines from four X-linked Om loci were examined. 80 were Om and 106 were non-Om; in all instances an in situ hybridization signal, when probed with sn9g insert, was found at appropriate locations on the polytene chromosomes. Linkage was complete and showed that the sn9g insert was homologous to sequences localized at the sites of Om mutants. Preliminary analysis of several isolated clones of the tom element indicate a fairly conserved structure typical of copia-like elements. DNA sequence analysis of the tom at sn9g and Om(lD)9g showed direct repeats at the terminai that is also characteristic of copia-like elements. On going southern blot studies of several OM(lD) mutations indicate that some are due to insertions of a single tom, others appear to be due to multiple copies and yet others show no obvious alterations in the immedite vicinity of Om(lD)9g. Further investigations of the tom elements and the Om mutations should provide insight into the mechanisms underlying this very unusual mutational process.