Molecular Genetics of the Cut Locus in Drosophila

黑腹果蝇的切割位点是一个大于200kb的大基因，具有复杂的互补模式。活突变的两个互补组中的每一个都具有不同的表型，两组突变影响不同的组织。还有一些致命等位基因的互补群，其中一个不能补充所有的切割位点突变。其中两个致命的互补群有一个特别有趣的表型。在突变体中，所有的外部感觉器官，包括外部结构和支配它们的神经元，都转化为形态和抗原性不同的内部感觉器官。幼虫和成虫均可观察到这种转变。来自五个互补组的突变已经被绘制出来，每个组的突变落在基因的不同部分。这一建议将切割位点的复杂遗传学与其在分子水平上的活性联系起来。将分析野生型和突变型果蝇的转录，并将个体转录物与互补群进行关联。将对特定的cdna进行测序，以确定切割时是否合成了一种以上的蛋白质。果蝇中的复杂基因有可能提供对其他系统中尚未获得的基因组调控特征的见解。该项目将为解决复杂基因，特别是切割位点的调控问题提供必要的基础工作。

The cut locus of Drosophila melanogaster is a large gene of more than 200 kb, with a complex pattern of complementation. Each of the two complementation groups of viable mutations has a different phenotype, and the two groups of mutations affect different tissues. There are also a number of complementation groups of lethal alleles, one of which fails to complement all cut locus mutations. Two of these lethal complementation groups have a particularly interesting phenotype. In mutant files, all of the external sensory organs, including both the external structures and the neurons that innervate them, are transformed into a morphologically and antigenically distinct, internal sensory organ. The transformation can be observed in both larvae and adults. Mutations from five of the complementation groups have been mapped, and the mutations from each group fall into a different part of the gene. This proposal sets out to correlate the complex genetics of the cut locus with its activity at a molecular level. Transcription will be analyzed in wild type and mutant flies, and individual transcripts will be correlated with complementations groups. Specific cDNAs will be sequenced in order to determine whether more than one protein is synthesized at cut. Complex genes in Drosophila have the potential to provide insight into regulatory features of genomes not accessible in other systems as yet. This project will provide the necessary ground work for approaching questions of regulation of complex genes, in particular, the cut locus.