Chromosomal Telomeres

我们正在研究果蝇的端粒区域，作为后生动物端粒的模型。我们已经证明，在果蝇中，与酵母不同，末端被删除的染色体可以遗传给许多世代。我们对端粒区域亚末端部分的结构分析揭示了不同重复序列的复杂分布。初步结果表明，末端和亚末端长度变异的频率出人意料地高。此外，我们还记录了一个案例，其中一个基因的表达被抑制，当它被转座到亚末端位置时。真核细胞染色体的末端被称为端粒，是被认为是染色体稳定所必需的特殊结构。最近的研究表明，在单细胞真核生物、脊椎动物和高等植物中，有一个特征的末端序列基序是保守的。在许多真核生物中，端粒区还包含更复杂的重复序列，这些重复序列在所有或某一子集或染色体顶端共享。端粒在单细胞真核生物中得到了最广泛的研究，但对多细胞真核生物端粒区域的整体序列组织、功能或动力学知之甚少。

We are examining the telomere region of the fruitfly, Drosophila melanogaster, as a model for metazoan telomeres. We have shown that in Drosophila, in contrast to yeast, a chromosome from which the terminus has been deleted can be transmitted for many generations. Our structural analysis of the subterminal portion of the telomere region has revealed a complex interspersion of different repetitive sequences. Preliminary results suggest an unexpectedly high frequency of terminal and subterminal length variations. In addition, we have documented a case in which the expression of a gene was repressed when it was transposed to a subterminal site. The termini of eukaryotic chromosomes, called telomeres, are specialized structures thought to be required for chromosome stability. It has recently been shown that a characteristic terminal sequence motif is conserved among unicellular eukaryotes, vertebrates and higher plants. In many eukaryotes the telomere region also encompasses more complex repetitive sequences that are shared among all or a subset or the chromosome tips. Telomeres have been studied most extensively in single-celled eukaryotes and there is little known about the overall sequence organization, functions, or dynamics of the telomere region of multicellular eukaryotes.***