《分子生物学》课程教学课件（PPT讲稿）Chapter 5 Biosynthesis of RNA

Transcription y Chapter 5 Biosynthesis of RNA

Chapter 5 Biosynthesis of RNA

Contents Part1 Introduction慨述 Part 2 Synthesis of RNA in prokaryotes原核生物RNA的合成 Part 3 Synthesis of RNA in eukaryotes真核生物RNA的合成 Part 4 Reverse transcription 转录 Part5 MicroRNA微RNA 2025/5/15 2

2025/5/15 2 Part 1 Introduction 概述 Contents Part 2 Synthesis of RNA in prokaryotes 原核生物RNA的合成 Part 3 Synthesis of RNA in eukaryotes 真核生物RNA的合成 Part 4 Reverse transcription 逆 转录 Part 5 MicroRNA 微RNA

KEY POINTS Definition of sense strand and anti-sense strand, general features of RNA synthesis. 有义链、反义链的概念，RNA合成的基本特性 Components and function of RNA polymerase in prokaryotes eukaryotes 原核与真核RNA聚合酶的组成及作用； 2025/5/15 3

2025/5/15 3 KEY POINTS • Definition of sense strand and anti-sense strand, general features of RNA synthesis. 有义链、反义链的概念，RNA合成的基本特性 • Components and function of RNA polymerase in prokaryotes & eukaryotes 原核与真核RNA聚合酶的组成及作用；

Structure and roles of prokaryotic eukaryotic promoters recognized by RNA polymerase 原核与真核RNA聚合酶识别的启动子结构与作用； Transcription bubble and transcription elongation; terminator and transcription termination 转录泡与转录延伸；终止子与转录终止。 Regulation mechanisms of microRNA and small interfering RNA;process of reverse transcription iRNA及siRNA的调控机理和逆转录过程。 2025/5/15

2025/5/15 4 • Structure and roles of prokaryotic & eukaryotic promoters recognized by RNA polymerase 原核与真核RNA聚合酶识别的启动子结构与作用； • Transcription bubble and transcription elongation; terminator and transcription termination 转录泡与转录延伸；终止子与转录终止。 • Regulation mechanisms of microRNA and small interfering RNA; process of reverse transcription miRNA 及siRNA的调控机理和逆转录过程

Part 1 Introduction概述 2025/5/15 5

2025/5/15 5 Part 1 Introduction 概述

How is a gene expressed? 基因是如何表达的？ The Central Dogma of Molecular Biology Gene expression Transcription Translation Replication DNA RNA Protein Transcription is camried out by RNA polymerase Translation is perfommed on ribosomes Replication is camried out by DNA polymerase Reverse transcriptase copies RNA into DNA 2025/5/15 The Central Dogma中心法则 6

2025/5/15 6 How is a gene expressed? 基因是如何表达的？ The Central Dogma 中心法则 Gene expression

一、Basic concepts一些基本概念： Gene expression（基因表达)： The process that the genetic information carried in a gene becomes the distinguishable phenotype,including two stages: transcription and translation指基因所携带的遗传信息转变成 可辨别的表型的整个过程，一般包括转录和翻译两个阶段。 Products of gene expression基因表达的产物： In most cases,the products are proteins or polypeptides, some might be RNA.Transcription is the first stage of gene expression.最常见的是蛋白质或多肽，也可能是RNA。转 2025暴是基因表达的第一阶段

2025/5/15 7 一、Basic concepts一些基本概念： Gene expression （基因表达）： The process that the genetic information carried in a gene becomes the distinguishable phenotype, including two stages: transcription and translation 指基因所携带的遗传信息转变成 可辨别的表型的整个过程，一般包括转录和翻译两个阶段。 Products of gene expression 基因表达的产物： In most cases, the products are proteins or polypeptides, some might be RNA. Transcription is the first stage of gene expression. 最常见的是蛋白质或多肽，也可能是RNA。转 录是基因表达的第一阶段

Transcription/,DNA transcription(转录)： Copying of one strand DNA into a complementary RNA sequence by the enzyme RNA polymerase. 以DNA为模板合成RNA的过程。 Translation/RNA Translation(翻译)： Process by which the sequence of nucleotides in a messenger RNA molecule directs the incorporation of amino acids into protein. 是指以RNA为模板，把核苷酸三联遗传密码子翻译成氨 基酸序列、合成多肽链的过程。 2025/5/15 8

2025/5/15 8 Transcription/DNA transcription（转录）： Copying of one strand DNA into a complementary RNA sequence by the enzyme RNA polymerase. 以DNA为模板合成RNA的过程。 Translation/RNA Translation（翻译）： Process by which the sequence of nucleotides in a messenger RNA molecule directs the incorporation of amino acids into protein. 是指以mRNA为模板，把核苷酸三联遗传密码子翻译成氨 基酸序列、合成多肽链的过程

Antisense strand(反义链)： Also called template strand or negative strand,the strand that guides synthesis of the messenger RNA according to the complementary base-pairing principle. 又称模板链，在DNA双链中，根据碱基互补原则指导mRNA 合成的DNA链，也叫负链。 Sense strand(有义链)： Also called non-template strand,coding strand or positive strand,the strand that is complementary to the template strand. 在DNA双链中，与模板链互补的非模板链〔与mRNA碱基序 列相同（除了T→U外)的那条DNA链)，又称编码链 (coding strand)或正链。 202551基因序列一般以正链DNA序列表示。 9

2025/5/15 9 Antisense strand （反义链）： Also called template strand or negative strand, the strand that guides synthesis of the messenger RNA according to the complementary base-pairing principle. 又称模板链，在DNA双链中，根据碱基互补原则指导mRNA 合成的DNA链，也叫负链。 Sense strand（有义链）： Also called non-template strand, coding strand or positive strand, the strand that is complementary to the template strand. 在DNA双链中，与模板链互补的非模板链〔与mRNA碱基序 列相同（除了T→U外）的那条DNA链〕，又称编码链 （coding strand）或正链。 基因序列一般以正链DNA序列表示

5’·.A T GG CC T GG A C TT C A.3 Sense strand of DNA 3>.T A CC GG A CC T G AA G T.5'Antisense strand of DNA 2025/5/15 10

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