EXPRESSION AND LOCATION OF DNA SEQUENCES ON CHROMOSOME 21

我们建议使用重复序列来寻找基因， 参与其他疾病的DS相关病理 受21号染色体的影响，并探索调节 重复序列在这些表达中的功能， 大脑中的其他基因。 计划进行以下实验： 1. 克隆的重复序列作为遗传标记的用途， 鉴定和分离沿21号染色体沿着异常DNA片段 定义缺失、易位和其他重排 在唐氏综合症和其他患者中观察到。 2. 在特定目的#1中分离的DNA片段的表征。 测序分析将揭示任何开放的阅读框架，以及是否 基因被放大了。进行染色体定位， 21号染色体上的序列。 3. 基因序列在RNA和蛋白质水平的表达。 我们 应使用特定目标#1中获得的基因序列，以及 来自胎儿脑cDNA文库的现有cDNA克隆映射到 21号染色体。 组织RNA原位杂交 16三体小鼠的胎脑切片与 将鉴定出基因序列， 优先杂交到一个或另一个。 这些序列和其他序列将被亚克隆到表达载体中， 并且将来自这些重组体的蛋白质产物注射到 植入小鼠体内以产生抗体。 免疫荧光检测 结合三体性胎儿脑组织切片的抗体 16小鼠或来自正常小鼠的细胞将定量地揭示或 这些基因序列是否表达 在胎儿16三体小鼠的大脑中的差异。 4. 研究人类特异性重复序列， 存在于21号染色体上。 重复序列特异于 将从21号染色体基因组文库中分离人类物种 差异杂交。 其监管作用将是 特别是在它们对基因表达的控制方面， 个脑袋

We propose to use repetitive sequences in search of genes that are involved in the pathology associated with DS on other diseases affected by chromosome 21 and also to explore the regulatory function of repetitive sequences in the expression of these and other genes in the brain. The following experiments are planned: 1. Use of cloned repetitive sequences as genetic markers to identify and isolate abnormal DNA fragments along chromosomal 21 defining deletions, translocations and other rearrangements observed in Down syndrome and other patients. 2. Characterization of DNA fragments isolated in specific aim #1. Sequencing analysis will reveal any open reading frames and whether gene is amplified. Chromosomal mapping is carried out to locate such sequences on chromosome 21. 3. Expression of gene sequences at the RNA and protein level. We shall use gene sequences obtained in specific aim #1 as well as existing cDNA clones from fetal brain cDNA library mapped to chromosome 21. In situ hybridization to RNA in tissue section of fetal brain from trisomy 16 mouse as compared to that of normal mouse will identify gene sequences that reveal preferential hybridization to one or the other. Such sequences and others will be subcloned into expression vector and the protein product from such recombinants will be injected into mice for antibody production. Immunofluorescence of such antibody which binds to tissue section of fetal brain of trisomy 16 mouse or that from normal mouse will reveal quantitatively or qualitatively whether these gene sequences are expressed differently in the brain of a fetal trisomy 16 mouse. 4. Study of repetitive sequences that are human specific and are present on chromosome 21. Repetitive sequences specific to the human species will be isolated from chromosome 21 genomic library by differential hybridization. Their regulatory role will be explored especially in their control of expression of genes In the brain.