A-Level Biology: Transcription and Translation — Protein Synthesis | 转录与翻译：蛋白质合成完全指南

A-Level 生物：转录与翻译——蛋白质合成完全指南

Protein synthesis is one of the most fundamental processes in molecular biology — and a cornerstone topic in A-Level Biology. It explains how the genetic information stored in DNA is converted into functional proteins, the workhorses of every living cell. Understanding transcription and translation is essential not only for exam success but also for grasping how life operates at the molecular level.

蛋白质合成是分子生物学中最基本的过程之一，也是A-Level生物学的核心主题。它解释了储存在DNA中的遗传信息如何转化为功能性蛋白质——每个活细胞的主力分子。理解转录和翻译不仅对考试成功至关重要，对理解生命在分子层面如何运作也同样关键。

1. The Central Dogma of Molecular Biology | 分子生物学的中心法则

The central dogma, first proposed by Francis Crick in 1958, describes the flow of genetic information in biological systems: DNA → RNA → Protein. DNA stores the genetic blueprint, messenger RNA (mRNA) carries a transcribed copy of the instructions, and ribosomes translate the mRNA sequence into a polypeptide chain that folds into a functional protein.

中心法则由Francis Crick于1958年首次提出，描述了生物系统中遗传信息的流动方向：DNA → RNA → 蛋白质。DNA储存遗传蓝图，信使RNA（mRNA）携带转录后的指令副本，核糖体将mRNA序列翻译成多肽链，后者折叠成功能性蛋白质。

The central dogma has two key stages: transcription (DNA → mRNA in the nucleus) and translation (mRNA → polypeptide at the ribosome). In eukaryotic cells, there is also an intermediate RNA processing step where pre-mRNA is modified into mature mRNA before it leaves the nucleus.

中心法则有两个关键阶段：转录（DNA → mRNA，发生在细胞核内）和翻译（mRNA → 多肽，发生在核糖体上）。在真核细胞中，还有一个中间的RNA加工步骤，前体mRNA在离开细胞核之前被修饰成成熟的mRNA。

2. Transcription: DNA to mRNA | 转录：从DNA到mRNA

Transcription is the process by which a specific segment of DNA is used as a template to synthesise a complementary strand of messenger RNA (mRNA). This process occurs in the nucleus of eukaryotic cells and is catalysed by the enzyme RNA polymerase.

转录是以特定DNA片段为模板合成互补信使RNA（mRNA）链的过程。该过程发生在真核细胞的细胞核中，由RNA聚合酶催化。

2.1 Initiation | 起始

Transcription begins when RNA polymerase binds to a specific DNA sequence called the promoter region, located upstream of the gene. In eukaryotes, transcription factors assist RNA polymerase in recognising and binding to the promoter. The most common promoter sequence in prokaryotes is the TATA box (Pribnow box), while eukaryotes have a similar TATA box along with additional regulatory elements like enhancers and silencers.

转录开始时，RNA聚合酶与位于基因上游的一个特定DNA序列——启动子区域结合。在真核生物中，转录因子协助RNA聚合酶识别并结合启动子。原核生物中最常见的启动子序列是TATA盒（Pribnow盒），而真核生物有类似的TATA盒以及增强子和沉默子等额外的调控元件。

Once bound, RNA polymerase unwinds approximately 10–20 base pairs of the DNA double helix, creating a transcription bubble. This exposes the template strand (also called the antisense or non-coding strand), which runs in the 3′ to 5′ direction. The complementary coding strand (sense strand) has the same sequence as the resulting mRNA (with thymine replaced by uracil).

一旦结合，RNA聚合酶解开DNA双螺旋约10-20个碱基对，形成转录泡。这暴露了模板链（也称为反义链或非编码链），其方向为3′到5′。互补的编码链（有义链）与最终mRNA的序列相同（只是胸腺嘧啶T被尿嘧啶U取代）。

2.2 Elongation | 延伸

During elongation, RNA polymerase moves along the template strand in the 3′ to 5′ direction, adding free RNA nucleotides to the growing mRNA strand in the 5′ to 3′ direction. This is a key point examiners love to test — nucleic acid synthesis always proceeds in the 5′ → 3′ direction.

在延伸阶段，RNA聚合酶沿模板链以3′到5′方向移动，以5′到3′方向将游离的RNA核苷酸添加到不断增长的mRNA链上。这是考官喜欢测试的一个关键点——核酸合成总是以5′ → 3′方向进行。

The base pairing rules during transcription are:

转录过程中的碱基配对规则如下：

• Adenine (A) on the DNA template pairs with Uracil (U) in RNA (not thymine!)
• Thymine (T) on the DNA template pairs with Adenine (A) in RNA
• Cytosine (C) pairs with Guanine (G)
• Guanine (G) pairs with Cytosine (C)

• DNA模板上的腺嘌呤（A）与RNA中的尿嘧啶（U）配对（不是胸腺嘧啶！）
• DNA模板上的胸腺嘧啶（T）与RNA中的腺嘌呤（A）配对
• 胞嘧啶（C）与鸟嘌呤（G）配对
• 鸟嘌呤（G）与胞嘧啶（C）配对

As RNA polymerase advances, the DNA double helix reforms behind it. The growing mRNA strand peels away from the template, and the transcription bubble moves forward along the gene.

随着RNA聚合酶前进，DNA双螺旋在其后方重新形成。不断增长的mRNA链从模板上剥离，转录泡沿基因向前移动。

2.3 Termination | 终止

In prokaryotes, transcription terminates when RNA polymerase encounters a terminator sequence in the DNA. There are two main mechanisms: Rho-independent termination (hairpin loop formation in the mRNA causing RNA polymerase to stall and detach) and Rho-dependent termination (the Rho protein binds to the mRNA and pushes RNA polymerase off).

在原核生物中，当RNA聚合酶遇到DNA中的终止子序列时，转录终止。主要有两种机制：Rho非依赖性终止（mRNA中形成发夹环导致RNA聚合酶停滞并脱离）和Rho依赖性终止（Rho蛋白与mRNA结合并将RNA聚合酶推开）。

In eukaryotes, termination is more complex. RNA polymerase II transcribes past the polyadenylation signal sequence (AAUAAA). The pre-mRNA is then cleaved downstream of this signal, and the RNA polymerase eventually dissociates from the DNA template.

在真核生物中，终止过程更为复杂。RNA聚合酶II转录经过多聚腺苷酸化信号序列（AAUAAA）。然后pre-mRNA在该信号下游被切割，RNA聚合酶最终从DNA模板上解离。

3. RNA Processing (Eukaryotes Only) | RNA加工（仅真核生物）

The initial transcript produced by eukaryotic transcription is called pre-mRNA (or primary transcript). Before it can be translated, it must undergo three key modifications, collectively known as RNA processing:

真核生物转录产生的初始转录本称为前体mRNA（或初级转录本）。在被翻译之前，它必须经历三种关键修饰，统称为RNA加工：

3.1 Capping (5′ Cap) | 加帽（5′端帽）

A modified guanine nucleotide (7-methylguanosine) is added to the 5′ end of the pre-mRNA. This 5′ cap protects the mRNA from degradation by exonucleases, facilitates export from the nucleus, and helps the ribosome recognise the mRNA during translation initiation.

一个修饰的鸟嘌呤核苷酸（7-甲基鸟苷）被添加到pre-mRNA的5′端。这个5′端帽保护mRNA免受外切核酸酶的降解，促进其从细胞核输出，并帮助核糖体在翻译起始时识别mRNA。

3.2 Polyadenylation (Poly-A Tail) | 多聚腺苷酸化（Poly-A尾）

After transcription passes the polyadenylation signal (AAUAAA), an enzyme called poly-A polymerase adds approximately 150–250 adenine nucleotides to the 3′ end of the pre-mRNA. This poly-A tail also protects the mRNA from degradation and aids in nuclear export. The length of the poly-A tail influences the mRNA’s stability and translational efficiency.

转录经过多聚腺苷酸化信号（AAUAAA）后，一种称为poly-A聚合酶的酶向pre-mRNA的3′端添加约150-250个腺嘌呤核苷酸。这个poly-A尾同样保护mRNA免受降解并协助核输出。poly-A尾的长度影响mRNA的稳定性和翻译效率。

3.3 Splicing | 剪接

Eukaryotic genes contain introns (non-coding intervening sequences) and exons (coding sequences that are expressed). During splicing, introns are removed and exons are joined together to form a continuous coding sequence. This process is carried out by a large RNA-protein complex called the spliceosome, which is composed of small nuclear ribonucleoproteins (snRNPs).

真核基因含有内含子（非编码的间隔序列）和外显子（被表达的编码序列）。在剪接过程中，内含子被移除，外显子连接在一起形成连续的编码序列。该过程由称为剪接体的大型RNA-蛋白质复合体执行，剪接体由小核核糖核蛋白（snRNP）组成。

A fascinating extension of splicing is alternative splicing, where different combinations of exons can be joined together to produce multiple mRNA variants — and thus multiple different proteins — from a single gene. This is a key mechanism by which the human genome (with only ~20,000 protein-coding genes) can produce over 100,000 different proteins.

剪接的一个迷人延伸是可变剪接——外显子的不同组合可以连接在一起，从单个基因产生多种mRNA变体，从而产生多种不同的蛋白质。这是人类基因组（仅约20,000个蛋白质编码基因）能产生超过100,000种不同蛋白质的关键机制。

4. Translation: mRNA to Protein | 翻译：从mRNA到蛋白质

Translation is the process by which the nucleotide sequence of mRNA is decoded into the amino acid sequence of a polypeptide. It occurs on ribosomes in the cytoplasm (or on the rough endoplasmic reticulum) and requires transfer RNA (tRNA) molecules as adaptors between the mRNA code and amino acids.

翻译是将mRNA的核苷酸序列解码为多肽氨基酸序列的过程。它发生在细胞质（或粗面内质网）的核糖体上，并需要转运RNA（tRNA）分子作为mRNA密码与氨基酸之间的适配器。

4.1 The Genetic Code | 遗传密码

The genetic code is a set of rules by which the sequence of nucleotides in mRNA is translated into the sequence of amino acids in a polypeptide. Each three-nucleotide sequence, called a codon, specifies one amino acid (or a stop signal). Key features of the genetic code:

遗传密码是一套规则，按此规则mRNA中的核苷酸序列被翻译为多肽中的氨基酸序列。每个三核苷酸序列称为一个密码子，指定一个氨基酸（或终止信号）。遗传密码的主要特征：

• Triplet code: Three nucleotides (a codon) code for one amino acid
• Degenerate (redundant): Multiple codons can specify the same amino acid (e.g., both UUU and UUC code for phenylalanine)
• Non-overlapping: Each nucleotide is part of only one codon
• Universal: The same code is used by almost all organisms (with minor exceptions in mitochondria and some protists)
• Start codon: AUG codes for methionine and serves as the initiation signal
• Stop codons: UAA, UAG, and UGA do not code for any amino acid; they signal termination of translation

• 三联体密码：三个核苷酸（一个密码子）编码一个氨基酸
• 简并性（冗余性）：多个密码子可以指定同一个氨基酸（例如UUU和UUC都编码苯丙氨酸）
• 非重叠性：每个核苷酸只属于一个密码子
• 通用性：几乎所有生物都使用相同的密码（线粒体和某些原生生物中有微小例外）
• 起始密码子：AUG编码甲硫氨酸并作为翻译起始信号
• 终止密码子：UAA、UAG和UGA不编码任何氨基酸；它们发出翻译终止的信号

4.2 tRNA and Amino Acid Activation | tRNA与氨基酸活化

Each tRNA molecule has a distinctive cloverleaf structure with two critical regions: the anticodon (a triplet of nucleotides complementary to an mRNA codon) at the bottom loop, and an amino acid attachment site (CCA sequence) at the 3′ end. The enzyme aminoacyl-tRNA synthetase catalyses the attachment of a specific amino acid to its corresponding tRNA in a process called aminoacylation (or charging). This reaction requires ATP.

每个tRNA分子具有独特的三叶草结构，有两个关键区域：底部环上的反密码子（与mRNA密码子互补的三核苷酸）和3′端的氨基酸附着位点（CCA序列）。氨酰tRNA合成酶催化特定氨基酸与其对应tRNA的连接，该过程称为氨酰化（或装载），需要ATP。

There are 20 different aminoacyl-tRNA synthetases — one for each amino acid. This ensures the fidelity of translation: the correct amino acid must be attached to the correct tRNA, as the anticodon-codon pairing at the ribosome determines which amino acid is incorporated.

共有20种不同的氨酰tRNA合成酶——每种氨基酸对应一种。这确保了翻译的准确性：正确的氨基酸必须附着在正确的tRNA上，因为核糖体上的反密码子-密码子配对决定了哪个氨基酸被掺入。

4.3 Translation Initiation | 翻译起始

In eukaryotes, the small ribosomal subunit (40S) binds to the 5′ cap of the mRNA and scans along until it finds the start codon (AUG). This process is assisted by initiation factors. An initiator tRNA carrying methionine (tRNA^Met) pairs with the start codon via its anticodon (UAC). The large ribosomal subunit (60S) then joins to form the complete 80S ribosome, which has three key sites:

在真核生物中，小核糖体亚基（40S）与mRNA的5′端帽结合，沿mRNA扫描直到找到起始密码子（AUG）。该过程由起始因子协助。携带甲硫氨酸的起始tRNA（tRNA^Met）通过其反密码子（UAC）与起始密码子配对。然后大核糖体亚基（60S）加入，形成完整的80S核糖体，后者有三个关键位点：

• A site (aminoacyl site): Where the incoming aminoacyl-tRNA binds
• P site (peptidyl site): Where the growing polypeptide chain is held
• E site (exit site): Where the deacylated tRNA exits the ribosome

• A位（氨酰位）：进入的氨酰tRNA结合的位置
• P位（肽基位）：增长中的多肽链所占据的位置
• E位（出口位）：去酰化的tRNA离开核糖体的位置

4.4 Elongation | 延伸

Elongation proceeds through a repeating three-step cycle:

延伸通过一个重复的三步循环进行：

Step 1 — Codon Recognition: A new aminoacyl-tRNA, whose anticodon is complementary to the next mRNA codon in the A site, binds to the ribosome. The correct tRNA is selected based on codon-anticodon base pairing. This step requires elongation factor EF-Tu (in prokaryotes) or eEF1 (in eukaryotes) and GTP hydrolysis.

第1步——密码子识别：一个新的氨酰tRNA（其反密码子与A位中下一个mRNA密码子互补）与核糖体结合。正确的tRNA基于密码子-反密码子碱基配对被选择。此步骤需要延伸因子EF-Tu（原核生物）或eEF1（真核生物）以及GTP水解。

Step 2 — Peptide Bond Formation: The enzyme peptidyl transferase (an rRNA component of the large ribosomal subunit — a ribozyme) catalyses the formation of a peptide bond between the amino acid in the P site and the amino acid in the A site. The growing polypeptide chain is transferred to the A-site tRNA.

第2步——肽键形成：肽基转移酶（大核糖体亚基的一个rRNA组分——一种核酶）催化P位氨基酸与A位氨基酸之间形成肽键。增长中的多肽链被转移到A位的tRNA上。

Step 3 — Translocation: The ribosome moves one codon (three nucleotides) along the mRNA in the 5′ to 3′ direction. This shifts the tRNA from the A site to the P site, and the now-empty tRNA from the P site to the E site, where it exits. Translocation requires elongation factor EF-G (prokaryotes) or eEF2 (eukaryotes) and GTP hydrolysis.

第3步——转位：核糖体沿mRNA以5′到3′方向移动一个密码子（三个核苷酸）。这将tRNA从A位移到P位，将空的tRNA从P位移到E位并离开核糖体。转位需要延伸因子EF-G（原核生物）或eEF2（真核生物）以及GTP水解。

This cycle repeats, adding one amino acid at a time, until the entire coding sequence has been translated. The process is remarkably fast — a prokaryotic ribosome can add about 20 amino acids per second.

这个循环不断重复，每次添加一个氨基酸，直到整个编码序列被翻译完毕。这个过程非常快——一个原核核糖体每秒可以添加约20个氨基酸。

4.5 Termination | 终止

Translation terminates when a stop codon (UAA, UAG, or UGA) enters the A site. There are no tRNAs with anticodons complementary to stop codons. Instead, release factors bind to the stop codon:

当终止密码子（UAA、UAG或UGA）进入A位时，翻译终止。没有tRNA具有与终止密码子互补的反密码子。取而代之的是，释放因子与终止密码子结合：

• Prokaryotes: RF1 recognises UAA and UAG; RF2 recognises UAA and UGA; RF3 (GTPase) facilitates release of RF1/RF2
• Eukaryotes: A single release factor, eRF1, recognises all three stop codons; eRF3 (GTPase) assists

• 原核生物：RF1识别UAA和UAG；RF2识别UAA和UGA；RF3（GTPase）促进RF1/RF2的释放
• 真核生物：单一的释放因子eRF1识别所有三个终止密码子；eRF3（GTPase）协助

Release factors promote the hydrolysis of the bond between the completed polypeptide and the tRNA in the P site. The polypeptide is released, and the ribosomal subunits, mRNA, and remaining factors dissociate.

释放因子促进已完成的多肽与P位tRNA之间键的水解。多肽被释放，核糖体亚基、mRNA和剩余因子解离。

5. Polyribosomes (Polysomes) | 多聚核糖体（多核糖体）

A single mRNA molecule can be translated by multiple ribosomes simultaneously. This structure, called a polyribosome or polysome, allows a cell to produce many copies of a protein rapidly from a single mRNA transcript. In electron micrographs, polysomes appear as a string of ribosomes “beads” on an mRNA “thread.”

单个mRNA分子可以被多个核糖体同时翻译。这种结构称为多聚核糖体或多核糖体，使细胞能够从单个mRNA转录本快速产生许多蛋白质副本。在电子显微镜图像中，多核糖体表现为mRNA”线”上的一串核糖体”珠子”。

6. Post-Translational Modifications | 翻译后修饰

The polypeptide chain released from the ribosome is often not yet a functional protein. It must undergo post-translational modifications, which can include:

从核糖体释放的多肽链通常还不是有功能的蛋白质。它必须经历翻译后修饰，可能包括：

• Folding: Assisted by chaperone proteins (e.g., Hsp70, Hsp90, chaperonins) to achieve the correct three-dimensional conformation
• Proteolytic cleavage: Removal of the initiator methionine or cleavage of signal peptides
• Chemical modifications: Phosphorylation, glycosylation, acetylation, methylation, ubiquitination
• Disulfide bond formation: Covalent bonds between cysteine residues stabilise tertiary structure
• Subunit assembly: Quaternary structure formation (e.g., haemoglobin is composed of 2 α-globin and 2 β-globin subunits)

• 折叠：由分子伴侣蛋白（如Hsp70、Hsp90、伴侣蛋白）协助实现正确的三维构象
• 蛋白水解切割：移除起始甲硫氨酸或切除信号肽
• 化学修饰：磷酸化、糖基化、乙酰化、甲基化、泛素化
• 二硫键形成：半胱氨酸残基之间的共价键稳定三级结构
• 亚基组装：四级结构形成（例如血红蛋白由2个α-珠蛋白和2个β-珠蛋白亚基组成）

7. Key Differences: Prokaryotes vs. Eukaryotes | 关键区别：原核生物 vs. 真核生物

A-Level exam questions frequently test the differences between prokaryotic and eukaryotic protein synthesis. Here are the key distinctions:

A-Level考试题目经常测试原核和真核蛋白质合成之间的区别。以下是主要区别：

Feature | 特征	Prokaryotes | 原核生物	Eukaryotes | 真核生物
Location | 位置	Cytoplasm (coupled transcription-translation)	Transcription in nucleus; translation in cytoplasm
RNA processing | RNA加工	No (mRNA is directly translated)	Yes (5′ cap, poly-A tail, splicing)
Introns | 内含子	Rare	Common in most genes
Ribosome size | 核糖体大小	70S (50S + 30S subunits)	80S (60S + 40S subunits)
Start codon | 起始密码子	AUG (codes for N-formylmethionine)	AUG (codes for methionine)
mRNA lifespan | mRNA寿命	Short (minutes)	Longer (hours to days)
Simultaneous translation | 同时翻译	Yes (polyribosomes form during transcription)	No (RNA processing required first)

8. Common Exam Questions and Tips | 常见考试问题与技巧

Common Question Types | 常见题型

1. Describe the process of transcription (4–6 marks): Mention DNA unwinding, RNA polymerase binding to the promoter, complementary base pairing (A-U, T-A, C-G, G-C), synthesis in the 5′ → 3′ direction, and formation of pre-mRNA. For eukaryotes, add RNA processing steps.

1. 描述转录过程（4-6分）：提及DNA解旋、RNA聚合酶与启动子结合、互补碱基配对（A-U、T-A、C-G、G-C）、以5′ → 3′方向合成以及pre-mRNA的形成。对于真核生物，加上RNA加工步骤。

2. Describe the process of translation (5–8 marks): Cover mRNA binding to the ribosome, codon recognition at the A site, tRNA anticodon pairing, peptide bond formation catalysed by peptidyl transferase, translocation of the ribosome, stop codon recognition by release factors, and polypeptide release.

2. 描述翻译过程（5-8分）：涵盖mRNA与核糖体结合、A位密码子识别、tRNA反密码子配对、肽基转移酶催化的肽键形成、核糖体转位、释放因子识别终止密码子以及多肽释放。

3. Compare transcription and translation: Create a comparison table covering location, template, product, enzyme(s), monomers used, and direction of synthesis.

3. 比较转录和翻译：创建一个比较表，涵盖位置、模板、产物、酶、使用的单体以及合成方向。

4. Explain the consequences of a mutation on protein synthesis: Be specific about the type of mutation (substitution, insertion, deletion, frameshift) and trace its effect through transcription and translation to the final protein product.

4. 解释突变对蛋白质合成的影响：具体说明突变类型（替换、插入、缺失、移码），并追踪其通过转录和翻译对最终蛋白质产物的影响。

Exam Tips | 考试技巧

• Direction matters: Always specify the direction of synthesis (5′ → 3′) and the direction of template reading (3′ → 5′)
• Enzyme names: Know RNA polymerase, aminoacyl-tRNA synthetase, and peptidyl transferase specifically
• Bond types: Hydrogen bonds (between complementary bases), phosphodiester bonds (in the sugar-phosphate backbone), and peptide bonds (between amino acids)
• Energy: ATP is required for amino acid activation; GTP is consumed during translation elongation and translocation
• Use the correct terminology: “Pre-mRNA” (not just “mRNA”) for the initial transcript in eukaryotes; specify “template strand” vs “coding strand”
• Draw and label diagrams: Practice drawing and labelling a ribosome with A, P, and E sites, and a tRNA molecule with anticodon and amino acid attachment site

• 方向很重要：始终指定合成方向（5′ → 3′）和模板阅读方向（3′ → 5′）
• 酶的名称：具体了解RNA聚合酶、氨酰tRNA合成酶和肽基转移酶
• 键的类型：氢键（互补碱基之间）、磷酸二酯键（糖-磷酸骨架中）和肽键（氨基酸之间）
• 能量：氨基酸活化需要ATP；翻译延伸和转位消耗GTP
• 使用正确术语：真核生物初始转录本用”pre-mRNA”（而非仅”mRNA”）；指定”模板链”与”编码链”
• 画图并标注：练习绘制并标注带A、P、E位的核糖体，以及带反密码子和氨基酸附着位点的tRNA分子

9. Summary — The Big Picture | 总结——全局视角

Protein synthesis is the elegant molecular machinery that converts the static information in DNA into the dynamic, functional world of proteins. From the unwinding of DNA by RNA polymerase, through the splicing and processing of pre-mRNA, to the rhythmic dance of tRNA molecules through the ribosome — every step is finely orchestrated.

蛋白质合成是一套精妙的分子机器，将DNA中的静态信息转化为动态的、功能性的蛋白质世界。从RNA聚合酶解开DNA，到pre-mRNA的剪接和加工，再到tRNA分子在核糖体中有节奏的舞动——每一步都经过精准的编排。

For A-Level students, mastering this topic means understanding not just the “what” but the “why” — why the 5′ cap is added, why the genetic code is degenerate, and why coupled transcription-translation in prokaryotes is so efficient. When you can explain the entire process from gene to protein with confidence, you have truly understood one of biology’s most beautiful stories.

对于A-Level学生来说，掌握这个主题意味着不仅要理解”是什么”，还要理解”为什么”——为什么要添加5′端帽，为什么遗传密码是简并的，以及为什么原核生物中的偶联转录-翻译如此高效。当你能够自信地解释从基因到蛋白质的整个过程时，你就真正理解了生物学中最美丽的故事之一。

Key Vocabulary | 核心词汇表

English | 英文	中文
Transcription	转录
Translation	翻译
Protein Synthesis	蛋白质合成
Central Dogma	中心法则
RNA Polymerase	RNA聚合酶
Promoter	启动子
Template Strand	模板链
Coding Strand	编码链
5′ Cap	5′端帽
Poly-A Tail	Poly-A尾
Splicing	剪接
Intron / Exon	内含子 / 外显子
Spliceosome	剪接体
Alternative Splicing	可变剪接
Codon	密码子
Anticodon	反密码子
Genetic Code	遗传密码
tRNA (Transfer RNA)	转运RNA
mRNA (Messenger RNA)	信使RNA
Ribosome	核糖体
A Site / P Site / E Site	A位 / P位 / E位
Peptidyl Transferase	肽基转移酶
Release Factor	释放因子
Polypeptide	多肽
Polyribosome (Polysome)	多聚核糖体（多核糖体）
Aminoacyl-tRNA Synthetase	氨酰tRNA合成酶