STRUCTURE AND ACTIVITY OF RIBOSOMAL GENES IN PHYSARUM

本项目研究低等真核生物核糖体RNA的编码基因 多头绒泡菌 这些基因位于一个巨大的回文DNA 在疟原虫中主要是染色体外的分子。 它们可以 以毫克数量与其相关的组蛋白一起分离， 调节蛋白 我们克隆了核糖体的限制性片段 基因，并打算测序重要的转录调控区， 插入序列。 我们将阐明具体的起源和功能 单链缺口和紧密结合的蛋白质在rDNA末端。 我们将 检查rDNA回文序列与染色体DNA成分的关联。 通过使用荧光标记的组蛋白，我们将确定 转录过程中发生的核小体结构变化。 我们将 继续研究转录水平上核小体的位置和结构， 调控序列以及转录和非转录的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.