14.1 Introduction 14.2 Breakage and reunion involves heteroduplex DNA 14.3 Double-strand breaks initiate recombination 14.4 Double-strand breaks initiate snapsis 14.5 Bacterial recombination involves single-strand assimilation 14.6 Gene conversion accounts for interallelic recombination 14.7 Topological manipulation of DNA 14.8 Specialized recombination involves breakage and reunion at specific sites 14.9 Repair systems correct damage to DNA 14.10 Excision repair systems in E. coli 14.11 Controlling the direction of mismatch repair 14.12 Retrieval systems in E. coli 14.13 RecA triggers the SOS system 14.14 Eukaryotic repair systems

第一节 遗传密码 • 概念 • 遗传密码的基本特性 第二节 tRNA 1、tRNA的结构 2、tRNA的功能 3、tRNA的种类 4、氨酰tRNA合成酶 第三节 核糖体 结构 自我组装 活性位点

● 遗传密码——三联子 ● tRNA的结构、功能与种类 ● 核糖体的结构与功能 ● 蛋白质合成的过程 ● 蛋白质的运转机制

● 基本概念 ● 转录起始： RNA聚合酶、启动子 ● 转录的基本过程 ● 转录后加工 ● 原核生物与真核生物mRNA的特征比较 ● RNA合成与DNA合成异同点

•tRNA剪接 •rRNA剪接 •Ⅰ型内含子剪接——自我剪接 •Ⅱ型内含子剪接——自我剪接 • Pre-mRNA剪接——剪接体剪接

17.1 Introduction 17.2 The mating pathway is triggered by pheromone-receptor interactions 17.3 The mating response activates a G protein 17.4 Yeast can switch silent and active loci for mating type 17.5 The MAT locus codes for regulator proteins 17.6 Silent cassettes at HML and HMR are repressed 17.7 Unidirectional transposition is initiated by the recipient MAT locus 17.8 Regulation of HO expression 17.9 Trypanosomes switch the VSG frequently during infection 17.10 New VSG sequences are generated by gene switching 17.11 VSG genes have an unusual structure 17.12 The bacterial Ti plasmid causes crown gall disease in plants 17.13 T-DNA carries genes required for infection 17.14 Transfer of T-DNA resembles bacterial conjugation 17.15 Selection of amplified genomic sequences 17.16 Transfection introduces exogenous DNA into cells 17.17 Genes can be injected into animal eggs 17.18 ES cells can be incorporated into embryonic mice 17.19 Gene targeting allows genes to be replaced or knocked out

第三节 色氨酸操纵子 Trp操纵子的结构 可阻遏的负调控-粗调 弱化系统-细调 第四节 其他操纵子 半乳糖操纵子 阿拉伯糖操纵子 第六节 转录后水平的调控 一．反义RNA—与mRNA互补的RNA 二．翻译量的调控 重叠基因的控制-两种蛋白的等量翻译 稀有密码子的影响-数量较少的蛋白 三、核糖体蛋白合成自体调控 四、翻译时的通读和移码-RF2的自体调控 五、信息体（informasome） 六、翻译中的弱化子控制

一、RNA转录概述 二、细菌的RNA聚合酶及其转录 三、真核生物的RNA聚合酶及其转录 四、真核生物基因转录的启动子 五、Ⅱ类基因转录的转录因子和转录起始复合物

16.1 Introduction 16.2 The retrovirus life cycle involves transposition-like events 16.3 Retroviral genes codes for polyproteins 16.4 Viral DNA is generated by reverse transcription 16.5 Viral DNA integrates into the chromosome 16.6 Retroviruses may transduce cellular sequences 16.7 Yeast Ty elements resemble retroviruses 16.8 Many transposable elements reside in D. melanogaster 16.9 Retroposons fall into two classes 16.10 The Alu family has many widely dispersed members

12.1 Introduction 12.2 Replicons can be linear or circular 12.3 Origins can be mapped by autoradiography and electrophoresis 12.4 The bacterial genome is a single circular replicon 12.5 Each eukaryotic chromosome contains many replicons 12.6 Isolating the origins of yeast replicons 12.7 D loops maintain mitochondrial origins 12.8 The problem of linear replicons