Warmke J W, Kreuz A J, Falkenthal S
Department of Molecular Genetics, Ohio State University, Columbus 43210.
Genetics. 1989 May;122(1):139-51. doi: 10.1093/genetics/122.1.139.
Using overlapping synthetic deficiencies, we find that a haplo-insufficient locus affecting flight behavior and the myosin light chain-2 gene co-map to the Drosophila melanogaster polytene chromosome interval 99D9-E1 to 99E2-3. From screening over 9000 EMS-treated chromosomes, we obtained alleles of two complementation groups that map to this same interval. One of these complementation groups lfm(3)99Eb, exhibits dominant flightless behavior; thus, flightless behavior of the deficiency is in all likelihood due to hemizygosity of this single locus. Rescue of flightless behavior by a duplication indicates that the single allele, E38, of the Ifm(3)99Eb complementation group is a hypomorph. Based upon its map position and a reduction in concentration of myosin light chain-2 mRNA in heterozygotes, we propose that Ifm(3)Eb(E38) is a mutant allele of the myosin light chain-2 gene. Our genetic analysis also resulted in the identification of four dominant flightless alleles of an unlinked locus, l(3)nc99Eb, that exhibits dominant lethal synergism with Ifm(3)99Eb.
利用重叠的合成缺陷，我们发现一个影响飞行行为的单倍不足基因座与肌球蛋白轻链-2基因共同定位于黑腹果蝇多线染色体区间99D9-E1至99E2-3。通过筛选9000多条经EMS处理的染色体，我们获得了两个互补群的等位基因，它们都定位于同一区间。其中一个互补群lfm(3)99Eb表现出显性的飞行缺陷行为；因此，该缺陷导致的飞行缺陷行为很可能是由于这个单一位点的半合子状态。通过重复片段对飞行缺陷行为的挽救表明，Ifm(3)99Eb互补群的单一等位基因E38是一个亚效等位基因。基于其图谱位置以及杂合子中肌球蛋白轻链-2 mRNA浓度的降低，我们提出Ifm(3)Eb(E38)是肌球蛋白轻链-2基因的一个突变等位基因。我们的遗传分析还鉴定出了一个不连锁基因座l(3)nc99Eb的四个显性飞行缺陷等位基因，该基因座与Ifm(3)99Eb表现出显性致死协同作用。
