STRUCTURE AND ACTIVITY OF RIBOSOMAL GENES IN PHYSARUM

该项目涉及低等真核生物中编码核糖体rna的基因。 多头绒泡菌。这些基因位于一个巨大的回文DNA上 在疟原虫中主要是染色体外的分子。他们可以是 以毫克量与其相关的组蛋白和 调节蛋白。我们已经克隆了核糖体的限制性片段 基因，并打算对重要的转录调节区和 插入的序列。我们将阐明特定的起源和功能 RDNA末端的单链间隙和紧密结合的蛋白质。我们会 检查rDNA回文与染色体DNA成分的关联。 通过使用荧光标记的组蛋白，我们将确定 在转录过程中发生的核小体结构变化。我们会 继续研究核小体在转录水平上的位置和结构 调节序列以及转录和非转录rDNA区域。

This project concerns the genes coding for ribosomal RNA in the lower eukaryote Physarum polycephalum. These genes are located on a giant palindromic DNA molecule which is predominantly extrachromosomal in plasmodia. They can be isolated in milligram quantities together with their associated histones and regulatory proteins. We have cloned restriction fragments of the ribosomal genes and intend to sequence important transcriptional regulatory regions and intervening sequences. We shall elucidate the origin and functions of specific single-strand gaps and tightly-bound proteins at the rDNA termini. We shall examine the association of the rDNA palindrome with chromosomal DNA components. Through use of fluorescent-labeled histone we shall determine the nature of nucleosome structural changes which occur during transcription. We shall continue to examine the location and structure of nucleosomes on transcriptional regulatory sequences and on transcribed and non-transcribed rDNA regions.