Expression of many genes in cells are regulated Housekeeping genes(管家基因)： expressed constitutively(组成性表 达)，essential for basic processes involving in cell replication and growth. Inducible genes(可诱导基因)： expressed only when they are activated by inducers or cellular factors
Housekeeping genes (管家基因）: expressed constitutively（组成性表 达）, essential for basic processes involving in cell replication and growth. Inducible genes（可诱导基因）: expressed only when they are activated by inducers or cellular factors. Expression of many genes in cells are regulated
1-1 cell proteins are divided into two categories: constitutive protein(组成型蛋白质)： In cells,many proteins are the necessary enzymes or proteins in the metabolism, the number of these proteins is not almost affected by the environment or metabolic state. regulated or adaptive protein(调节型或 适应型蛋白质)： the synthesis rate of these proteins is significantly affected by the environment
constitutive protein(组成型蛋白质)： 1-1 cell proteins are divided into two categories: In cells, many proteins are the necessary enzymes or proteins in the metabolism, the number of these proteins is not almost affected by the environment or metabolic state. regulated or adaptive protein (调节型或 适应型蛋白质)： the synthesis rate of these proteins is significantly affected by the environment
1-2 gene regulation ■gene expression(基因表达)： refers to the whole process in which the genetic information carried by a gene is converted into a discernible phenotype, generally including two stages,transcription and translation. gene regulation or gene control 因表达调控) refers to a process in which the gene expression is regulated
gene expression（基因表达）： 1-2 gene regulation gene regulation or gene control（基 因表达调控） refers to a process in which the gene expression is regulated. refers to the whole process in which the genetic information carried by a gene is converted into a discernible phenotype, generally including two stages, transcription and translation
Gene regulation occurs mainly in two levels ■1.transcriptional regulation转录水平上的调控 ■2.post-transcriptional regulation转录后水平 上的调控 processing of RNA transcript mRNA加工成熟水平上的调控 translation of mRNA 翻译水平上的调控
Gene regulation occurs mainly in two levels ◼ 1. transcriptional regulation 转录水平上的调控 ◼ 2. post- transcriptional regulation 转录后水平 上的调控 processing of RNA transcript mRNA加工成熟水平上的调控 translation of mRNA 翻译水平上的调控
gene regulation is affected by the following factors(基因调控的指挥系统)： nutritional status（营养状况) ■In prokaryotes. environmental factor(环境因素) hormone level(激素水平) ■In eukaryotes developmental stage(发育阶段)
gene regulation is affected by the following factors (基因调控的指挥系统): ◼ In prokaryotes ◼ In eukaryotes nutritional status（营养状况） environmental factor（环境因素） hormone level（激素水平） developmental stage（发育阶段）