Structural gene is a gene that codes for any RNA or protein product other than a regulatory element (i.e.regulatory protein). ■Regulator gene or regulatory gene is a gene involved in controlling the expression of one or more other genes ■Operator gene A gene that interacts with a specific repressor to control the functioning of the 2025adjacent structural genes. 16
2025/5/15 16 ◼ Structural gene is a gene that codes for any RNA or protein product other than a regulatory element (i.e. regulatory protein). ◼ Regulator gene or regulatory gene is a gene involved in controlling the expression of one or more other genes . ◼ Operator gene A gene that interacts with a specific repressor to control the functioning of the adjacent structural genes
2-2 The types and characters of gene regulation in prokaryotes ■( Gene Expression is Controlled by Regulatory Proteins(调控蛋白) >Positive regulators or activators(激活蛋 INCREASE the transcription Negative regulators or repressors(阻遏蛋 DECREASE or ELIMINATE the transcription 2025/5/15 17
2025/5/15 17 ◼ Gene Expression is Controlled by Regulatory Proteins (调控蛋白) ➢ Positive regulators or activators （激活蛋 白） INCREASE the transcription ➢ Negative regulators or repressors (阻遏蛋 白) DECREASE or ELIMINATE the transcription 2-2 The types and characters of gene regulation in prokaryotes
1.According to the response of operon to the Regulatory Proteins gene regulation include: Negative transcription regulation(负转录调控) the products of regulator gene are repressors decrease the transcription of structural gene. Positive transcription regulation(正转录调控) the products of regulator gene are activators,increase the transcription of structural gene. 2025/5/15 18
2025/5/15 18 1、 According to the response of operon to the Regulatory Proteins Negative transcription regulation（负转录调控） Positive transcription regulation（正转录调控） the products of regulator gene are repressors，decrease the transcription of structural gene. the products of regulator gene are activators，increase the transcription of structural gene. gene regulation include:
Structural gene Regulator gene Operator gene acitivator repressor positive negative transcription transcription regulation regulation Positive transcription regulation If there are no regulatory proteins,the genes are turned off.otherwise,when there are regulatory proteins,the genes are turned on. 2025/5/15 19
2025/5/15 19 Regulator gene Operator gene Structural gene acitivator repressor positive transcription regulation Positive transcription regulation If there are no regulatory proteins, the genes are turned off. otherwise, when there are regulatory proteins, the genes are turned on. negative transcription regulation
Structural gene Regulator gene Operator gene acitivator repressor positive negative transcription transcription regulation regulation Negative transcription regulation If there are no regulatory proteins,the genes are turned on.otherwise,when there are regulatory proteins,the genes are turned off. 2025/5/15 20
2025/5/15 20 Regulator gene Operator gene Structural gene acitivator repressor positive transcription regulation Negative transcription regulation If there are no regulatory proteins, the genes are turned on. otherwise, when there are regulatory proteins, the genes are turned off. negative transcription regulation