RUI: A Mutational Analysis of the bg1 Expression in E. coli K-12

9316694 Lopilato基因使用一种称为转录装置的蛋白质复合物来表达或转录，该蛋白质复合物需要接触DNA。 然而，DNA被组蛋白高度压缩。 为了研究DNA结构如何影响基因表达，该项目利用了bgl操纵子，一组在大肠杆菌中发现的基因。 DNA结构的变化导致bgl表达。 当bgl操纵子表达时，细菌细胞可以利用β-葡糖苷糖。 然而，bgl操纵子在野生型细胞中是沉默的，因此细胞不能利用这些糖。 多种突变导致bgl操纵子表达，包括影响参与DNA扭曲或超螺旋的蛋白质的突变。 影响组蛋白样蛋白H-NS的突变导致bgl表达。 分析bgl表达的遗传学方法的目标是鉴定参与该操纵子的表达和调节的所有基因和基因产物。 为此，我分离了一个新的调控基因，bglJ。 该基因的突变导致bgl表达。我的具体目标是表征和分析bglJ基因的机制。 bglJ的表征将揭示bglJ是否编码一种新的组蛋白样蛋白。 研究bglJ表达可能有助于更好地了解DNA结构如何影响细菌中的基因表达。 ***

9316694 Lopilato Genes are expressed or transcribed using a complex of proteins called the transcriptional apparatus which requires access to DNA. However, DNA is highly compacted by histone proteins. To investigate how DNA structure affects gene expression, this project utilizes the bgl operon, a set of genes found in Escherichia coli. Changes in DNA structure result in bgl expression. When the bgl operon is expressed, the bacterial cell can utilize beta-glucoside sugars. However, the bgl operon is silent in wild-type cells, and therefore the cells cannot utilize these sugars. A variety of mutations cause the bgl operon to be expressed, including mutations that affect proteins involved in twisting or supercoiling the DNA. Mutations that affect the histone-like protein H-NS result in bgl expression. The goal of a genetic approach in analyzing bgl expression is to identify all the genes and gene product involved in the expression and the regulation of this operon. To this end, I have isolated a new regulatory gene, bglJ. A mutation in this gene results in bgl expression. My specific aims are to characterize and to analyze the mechanism of the bglJ gene. Characterization of bglJ will reveal whether bglJ encodes a novel histone-like protein. %%% Studying bglJ expression may lead to better understanding of how DNA structure affects gene expression in bacteria. ***