Gene library planning based on the salivary gland chromosome map of Drosophila melanogaster

本研究的目的是建立黑腹果蝇唾液腺染色体随机克隆文库，并以此为基础构建数据库系统。从黑腹果蝇λ噬菌体基因组文库中随机分离约800个克隆，构建噬菌体存量文库，并从每个克隆中提取DNA样本。我们用原位杂交技术将这些克隆定位在唾液腺染色体上。到目前为止，已经绘制了286个克隆，其余的正在进行中。190个克隆在染色体的单位点上被定位，其余96个（33.6%）在染色体的多位点上被定位。这些克隆被认为包含重复序列或可移动的遗传元素。其中，31个克隆在X上，40个克隆在2L上，55个克隆在2R上，35个在3L上，37个在3R上。这一结果表明，克隆是从基因组中随机选择的。假设泊松分布，具有重复序列的克隆的平均频率估计为0.409。另一方面，我们从世界各地的实验室收集了黑腹果蝇的DNA克隆，并将其绘制在唾液腺染色体上。到目前为止，我们获得了大约50个克隆体。此外，我们将从加州大学的G. Rubin博士那里获得P1噬菌体库克隆。当我们建立了这些收藏品的克隆库后，我们将开始按要求分发这些克隆的服务。

The purpose of this study is to establish a random clone library of Drosophila melanogaster which are mapped on the salivary gland chromosome and construct a data bank system based on them. we isolated about 800 clones randomly from the lambda phage genomic library of Drosophila melanogaster and constructed a phage stock library and extracted DNA samples from each clone. We mapped these clones on the salivary gland chromosome by in situ hybridization technique. Up to date, 286 clones are mapped and the rest of them are now under progress. 190 clones are mapped on the single sites on the chromosomes and the rest of 96 (33.6%) are mapped on the multiple locations. These clones are considered to contain repetitive sequences or the movable genetic elements. Among these clones which were mapped on the single sites, 31 were mapped on the X, 40 were mapped on the 2L, 55 were mapped on the 2R, 35 were mapped on the 3L and 37 were mapped on the 3R. This result indicates that clones were chosen randomly from the genome. Assuming the Poisson distribution the mean frequency of clones having a repetitive sequence is estimated to be 0.409.On the other hand, we collected DNA clones of Drosophila melanogaster which have been mapped on the salivary gland chromosomes from the laboratories of all over the world. We so far obtained about 50 clones. Further more we are to get P1 phage library clones from Dr. G. Rubin of Univ. of California. After we establish the clone bank of these collections, we will start service for distribute these clones on request.