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 camied out by RNA polymerase Translation is perfomed on ribosomes Replication is camied 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录是基因表达的第一阶段。 7
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RNA 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。 2025/51基因序列一般以正链DNA序列表示
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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