ORGANIZATION AND FUNCTION OF A HUMAN REPETITIVE SEQUENCE

从人类基因组中分离到一个低重复的2.2kb序列。 根据初步研究，我们怀疑这一序列是移动的或 转座因子。这项提议的主要目的是证实这一点。 假设，并发现这个序列是否是或的一部分 调节其他基因的表达。为此，我们建议： 1)对克隆的2.2kb重复DNA元件及相关成员进行测序 属于它的家族。M13克隆和桑格的双脱氧“测序程序将 用来获得核苷酸数据，这些数据将被分析用于开放阅读 框架、保守序列和其他类似逆转录病毒的特征 和转座因子。2)研究这种重复的组织方式 这个家族出现在人类基因组的不同部分。兰布达 将对人类12号染色体文库进行筛选，寻找符合以下条件的重组体 与2.2kb的序列杂交。从这样的重组体中提取的DNA将 与2.2kb序列相比，在组织和程度方面 杂交。3)通过以下方式研究重复家族的记录 来自不同细胞和组织的RNA的Northern杂交分析 筛选已有的cDNA文库。青枯菌RNA的Northern印迹分析 不同的来源会给我们关于大小和类型的信息 成绩单。含有与之同源序列的cDNA克隆的分析 2.2kb片段将揭示重复元件是否单独 转录的或仅与其他基因结合的。4)探索使用 2.2kb重复序列家族作为遗传学研究的标记。 家庭成员将用于绘制人类12号染色体的区域图谱 和21，并进一步扩展到检测微小的缺失和 限制性片段长度多态。这些研究将导致 关于一类重复序列之间关系的信息 人类基因组的调节、分化和发育。另外， 这些克隆的重复元件可能在医学上有应用 作为遗传标记用于检测遗传和发育 疾病，包括癌症。

A low-repetitive 2.2 kb sequence has been isolated from the human genome. Based on preliminary studies, we suspect that this sequence is a mobile or transposable element. The major aim of this proposal is to confirm this hypothnesis and to discover whether or not this sequence is a part of or regulates the expression of other genes. Toward this end, we propose: 1) to sequence a cloned 2.2 kb repetitive DNA element and related members of its family. M13 cloning and Sanger's dideoxy" sequencing procedure will be used to obtain nucleotide data which will be analyzed for open-reading frames, conserved sequence, and other features which resemble retroviruses and transposable elements. 2) to study the organization of this repeat family as it appears in various portions of the human genome. Lambda libraries of human chromosome 12 will be screened for recombinants which hybridize to the 2.2 kb sequence. DNA from such recombinants will be compared to the 2.2 kb sequence in terms of organization and degree of cross-hybridization. 3) to study transcripts of the repeat family by Northern blot analysis of RNA from various cells and tissues and by screening preexisting cDNA libraries. Northern blot analysis of RNA from different sources will give us information on the sizes and types of transcripts. Analysis of cDNA clones containing sequences homologous to the 2.2 kb fragment will reveal whether the repetitive element alone is transcribed or only in conjunction with other genes. 4) to explore the use of the 2.2 kb repetitive sequence family as markers for genetic studies. Family members will be used for regional mapping of human chromosomes 12 and 21 and further extended to the detection of small deletions and restriction fragment length polymorphisms. These studies will result in information regarding the relationship of a class of repetitive sequences to regulation, differentiation and development in the human genome. Also, these cloned repetitive elements mayt have application to medicine in their use as genetic markers for the detection of genetic and developmental diseases, including cancer.