GENOMIC PLASTICITY IN THE HUMAN U2 SNRNA GENE CLUSTER

描述：有几个与染色体结构相关的目标 并在重复的活性基因区域发挥作用，特别是 SnRNAU2和SnRNAU1基因。腺病毒12型E1B的观察 55KD蛋白可导致U2和U1染色体脆性 但仅在存在活性的P53基因产物的情况下。他们会 定义脆性所需的P53区域和功能。 他们将定义P53所需的55KD蛋白的区域 诱导脆弱。他们将尝试确定P53的区域 可能相互作用的55kD。跟进他们的 Cockayne综合征补充性B组(CSB)诱导的观察 在相同地区的脆弱性他们将决定这其中的哪些部分 大的蛋白质可以挽救正常的染色体凝集。他们会 培育CSB阴性突变体并检查U2基因座的染色体 在CSB诱导的间期、中期和脆性状态 突变最终将决定CSB诱导的脆弱性是否需要 P53。他们有证据表明，大型串联阵列的稳定 功能性U2基因需要一个CT70微卫星。他们将决定 这种稳定性的增强是否是USnRNA启动子所特有的 而CT重复序列的染色质结构是否依赖于活性 U2转录。最后，他们发现螺旋体(Cb) 优先关联U1和U2基因簇。他们会问 CBS与U2基因簇的关联是否需要SnRNA 转录，一个活跃的USnRNA编码区，或SnRNP蛋白结合 在近端或新释放的USnRNA上的位点。

DESCRIPTION : There are several goals related to chromosome structure and function in the area of repeated active genes, in particular the genes for snRNA U2 and snRNA U1. The observation that Adenovirus12 E1B 55KD protein can cause fragility in the chromosome at the U2 and U1 sites but only in the presence of an active p53 gene product. They will define the regions and functions of p53 that are required for fragility. They will define the regions of the 55KD protein required for p53 induction of fragility. They will try to identify the regions of p53 and 55KD that may interact with each other. To follow up their observation that Cockayne syndrome complementation group B (CSB) induces fragility in the same regions they will determine which portions of this large protein can rescue normal chromosome condensation. They will develop negative CSB mutants and examine the chromosome of the U2 locus in interphase and metaphase and in the fragile states induced by the CSB mutation Finally, will determine whether CSB induced fragility requires p53. They have evidence that stabilization of large tandem arrays of functional U2 genes requires a CT70 microsatellite. They will determine whether this enhancement of stability is specific for UsnRNA promoters and whether the chromatin structure of the CT repeat depends on active U2 transcription. Finally, they have found that the coiled bodies (CB) associate preferentially with U1 and U2 gene clusters. They will ask whether the association of CBs with the U2 gene cluster requires snRNA transcription, an active UsnRNA coding region, or snRNP protein binding sites on the nacent or newly released UsnRNA.