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Part V: How genes are regulated. Chapter 15: Gene Regulation in Prokaryotes Chapter 16: Gene Regulation in Eukaryotes. Chapter 15: Gene Regulation in Prokaryotes. Gene activity is regulated primarily at the level of transcription. lactose operon (lac operon).
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Part V: How genes are regulated Chapter 15: Gene Regulation in Prokaryotes Chapter 16: Gene Regulation in Eukaryotes
Gene activity is regulated primarily at the level of transcription
The action of CAP-cAMP complex in lac operon CAP ( catabolic gene activator protein) structure
cAMP(饥饿信号) 细菌 哺乳类动物 与分解物基因激活物结合的蛋白(catabolite gene activator protein,CAP) 激活PK 导致细胞内一系列酶活性的改变 发挥作用
The general condition of • regulation of gene expression • in prokaryotes • the change of environment • positive regulation & negative regulation
negative regulation repressor of lac bind to operator Positive regulation CAP-cAMP complex
trytophan operon (Trp operon ) a. Structure mechanism of regulation *negative regulation of repressor the structure of repressor attenuation
Attenuator located in L gene,contains a independent termination structure # the mechanism of attenuation
大肠杆菌 低Trp培养基 高Trp培养基 转录生成6720个AA的全长多顺反子mRNA 转录终止于L基因5’端140个AA