文档介绍：Gene Regulation in Eukaryotes
In eukaryotic cells, expression of a gene can be regulated at all those steps we saw in bacteria, and a few additional ones besides.
In many cases, a given transcript can be spliced in alternative ways to generate different products, and this too can be regulated.
The eukaryotic transcriptional machinery is more elaborate than its bacterial counterpart.
Nucleosomes and their modifier influence access to genes.
Many eukaryotic genes have more regulatory binding sites and are controlled by more regulatory proteins than are typical bacterial genes.
Promoter
Regulatory binding sites
Regulatory sequences: the stretch of DNA passing plete collection of regulator binding sites for a given gene.
In anisms , regulatory sequences can spread thousands of nucleotides from the promoter-both upstream and downstream –and can be made up of tens of regulator binding sites. Often these binding sites are grouped in unites called enhancers, and a given enhancer binds regulators responsible for activating the gene at a given time and place. Alternative enhancers bind different groups of regulators and control expression of the same gene at different times and places in response to different signals. (Figure 17-1)
FIGURE 17-1 The regulatory elements of a bacterial, yeast, and human gene.
OUTLINE
Conserved Mechanisms of Transcriptional Regulation from Yeast to Mammals
Recruitment of plexes to Genes by Eukaryotic Activators
Signal Integration binatorial Control
Transcriptional Repressors
Signal Transduction and the Control of Transcriptional Regulators
Gene “Silencing” by Modification of Histones and DNA
Eukaryotic Gene Regulation at Steps after Transcription Initiation
RNAs in Gene Regulation
CONSERVED MECHANISMS OF TRANSCRIPTIONAL REGULATION FROM YEAST TO MAMMALS
Many of the basic features of gene regulation are the same in all eukaryotes.
This is tested using a reporter gene. The reporter gene consists of binding sites for the yeast activator inser