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  • 翻译因子 - 高级

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    What are all these colored dots?
    ::这些彩色点是什么?

    These represent microarrays, which characterize patterns. Differential gene expression is a hallmark of many aspects of biology , from genetics and to physiology and evolution. What controls this differential gene expression? A lot of it has to do with factors.
    ::这些基因代表了微粒体,它们具有模式特征。不同的基因表达方式是生物学的许多方面的标志,从遗传学到生理学和进化。什么控制这种差异基因表达方式?其中有许多与因素有关。

    Transcription Factors
    ::翻译因素

    Transcription factors are that bind to regulatory elements on the DNA and have a significant role in the regulation of gene expression . Hence, one of many transcription factors is a DNA-binding domain. Transcription factors can activate or repress gene expression. In eukaryotic genes , transcription factors usually must bind to a gene's promoter prior to the binding of RNA polymerase and the initiation of transcription. This ensures that a gene is only expressed when its product is needed by the . 
    ::转录因子与DNA的监管要素有关,在基因表达方式的监管方面具有重要作用,因此,许多转录因子之一是具有DNA约束力的领域之一,转录因子可以激活或抑制基因表达方式。在Eukaryodic 基因中,转录因子通常必须在RNA聚合酶绑定和开始转录之前与基因促销者捆绑。这确保只有当基因需要其产品时才能表示基因。

    In eukaryotes , an important class of transcription factors is called general transcription factors (GTFs). These factors are necessary for transcription to occur. Many of these GTFs are part of the large transcription preinitiation complex that interacts with RNA polymerase directly. The most common GTFs are those that are involved in the RNA polymerase II-dependent transcription of DNA. These include the ubiquitous TFIIA, TFIIB, TFIID, TFIIE, TFIIF, and TFIIH. The preinitiation complex binds to promoter regions of DNA upstream to the gene that they regulate. TFIID is also known as the TATA binding protein as it binds to the TATA box .
    ::eukaryotes是一个重要的转录因数类别,称为一般转录因数(GTFs),这些因数是进行转录所必需的。许多这些转录因数是同RNA聚合酶直接互动的大型转录前启动综合体的一部分。最常见的转录前综合体是那些参与RNA聚合酶II依赖DNA转录的转录的基因,包括无处不在的TFIIIA、TFIIB、TFID、TFIIE、TFIIFIF和TFIIH。先发综合体将DNA上游区域与它们管制的基因连接起来。TFIID也称为TATA结合蛋白质,因为它与TATA盒结合。

    DNA and Protein Interactions
    ::DNA 和 DNA 蛋白丁酯相互作用

    DNA and proteins interact with each other for various reasons. Most of these reasons have to do with influencing the DNA structure or the expression of genes with in the DNA, a process known as gene expression. How the protein interacts with the DNA is based on the structure of the protein. Conserved DNA binding motifs are present among DNA binding proteins. These include domains known as the leucine zipper, the helix-turn-helix, the zinc finger and the helix-loop helix domains.
    ::DNA 和 DNA 和 DNA 蛋白因各种原因相互作用。 这些原因大多与DNA 中 DNA 结构 或 基因 表达 的 影响 有关 DNA 结构 或 DNA 中 基因 的 表达 相关 。 蛋白质 如何 与 DNA 互动 以 蛋白质 结构 为基础 。 在 DNA 结合 的 蛋白质 中 存在 DNA 绑定 的 motifs 。 这些 包括 Leucine 拉链 、 螺旋- turn- helix 、 锌指 和 螺旋- 环螺旋 区域 。

    The leucine-zipper (or the basic leucine zipper) domain contains an alpha helix with a leucine at every 7 th amino acid . If two leucine zipper domains find one another, the leucines can interact like the teeth in a zipper, allowing the dimerization of two proteins. When binding to the DNA, the leucine residues bind to the sugar-phosphate backbone while the helices sit in the major grooves.
    ::Leucine-zipper ( 或基本的 leucine lipper) 域内含有每七种氨基酸中含有一个 Leucene 的α螺旋藻。 如果两个 leucine izper 域互相发现, 则该 leucen izper 可以像拉链中的牙齿一样相互作用, 允许两种蛋白分解。 当与DNA结合时, leucine 残留物会与糖- 磷基脊捆绑在一起, 而象素则会坐在主要的槽中 。

    The helix-turn-helix is a major structural motif common in homeobox proteins involved the regulation of development. It is composed of two alpha helices joined by a short strand of amino acids.
    ::螺旋-转身-海利克斯是软木箱蛋白质中一种常见的主要结构元素,它涉及发育调节,由两头甲型肝脏组成,并配有短链氨基酸。

    The zinc finger domain consists of a DNA recognition helix and two antiparallel beta sheet structures. It is stabilized by coordinating zinc ions with regularly spaced zinc-coordinating histidine or cysteine residues. The Krüppel gap gene (see the Regulation of Gene Expression: Eukaryotic (Advanced) concept) is a zinc-finger protein.
    ::锌指域包括DNA识别螺旋体和两个抗平行贝贝壳结构,通过将锌离子与定期间隙的锌协调其丁丁或cysteine残留物相协调而稳定下来,Krüppel裂隙基因(见基因表达规范:Eukaryatic (Advanced)概念)是一种锌指蛋白质。

    The helix-loop-helix domain is characterized by two alpha helices connected by a loop, allowing DNA binding.
    ::Helix-loop-helix 域域的特征是两个以环连接的阿尔法向上,允许DNA结合。

    Specific Transcription Factors
    ::具体限定因素

    Specific transcription factors are factors that are specific for regulating specific genes. They are not ubiquitous for all RNA polymerase II associated genes. Specific factors vary considerably depending on the cis-regulatory sequences associated with the promoter region of a gene.
    ::具体转录系数是管制特定基因的具体因素,对于所有RNA聚合酶II相关基因来说,它们并非无处不在,具体因素因基因的促销区而异,因基因的精密调控顺序不同而有很大差异。

    Examples of specific transcription factors
    Factor Structural type Recognition sequence Binds as
    Sp1* Zinc finger 5'-GGGCGG-3' Monomer
    AP-1* Basic zipper 5'-TGA(G/C)TCA-3' Dimer
    C/EBP* Basic zipper 5'-ATTGCGCAAT-3' Dimer
    Heat shock factor Basic zipper 5'-XGAAX-3' Trimer
    ATF/CREB* Basic zipper 5'-TGACGTCA-3' Dimer
    c-Myc Basic helix-loop-helix 5'-CACGTG-3' Dimer
    Oct-1 Helix-turn-helix 5'-ATGCAAAT-3' Monomer
    NF-1* Novel 5'-TTGGCXXXXXGCCAA-3' Dimer
    • Sp1 = specificity protein 1
      ::SP1 = 特殊蛋白蛋白1
    • AP-1 = activator protein 1
      ::AP-1 = 活性体蛋白1
    • C/EBP = CCAAT-enhancer-binding protein
      ::C/EBP = CCAAT-加固加固加装蛋白蛋白蛋白
    • ATF/CREB = activating transcription factor/cAMP response element binding
      ::ATF/CREEB = 启动转录系数/CAMP反应要素
    • NF-1 = Nuclear factor I
      ::NF-1=核系数一

    Specificity Protein 1
    ::蛋白1

    Specificity Protein 1 , or Sp1, is involved in the early development of an organism . Sp1 directly binds DNA through a zinc finger motif. Sp1 binds to a regulatory sequence with the consensus sequence 5'-(G/T)GGGCGG(G/A)(G/A)(C/T)-3', which is known as a GC box element. Sp1 was first identified in 1983, making it one of the earliest transcription factors identified. It belongs to a family of transcription known as the Sp/KLF family (specificity protein/Krüppel-like factor).
    ::蛋白质1或Sp1参与生物体的早期开发。Sp1通过锌指模直接将DNA捆绑起来。Sp1与协商一致序列5'(G/T)GGGGG(G/A)(G/A)(C/T)-3'(称为GC框元素)的监管序列捆绑在一起。Sp1最初于1983年被确定为GC框元素,成为最早的转录系数之一,属于称为Sp/KLF家族(具体蛋白质/Krüppel类似元素)的转录式家族。

    Activator Protein 1
    ::活性者蛋白1

    AP-1, activator protein 1 , is also one of the earliest transcription factors identified. It activates the transcription of genes in response to a number of stimuli , including cytokines , growth factors, stress, and bacterial and viral infections, resulting in altered cellular processes such as differentiation , proliferation, and apoptosis. AP-1 is a heterodimeric protein composed of proteins belonging to the c-Fos, c-Jun, ATF and JDP families. c-Fos is a cellular proto-oncogene ; it belongs to the leucine zipper family of transcription factors. c-fos gene products dimerize with c-jun gene products through the leucine zipper to form AP-1. AP-1 activates transcription of genes containing the TPA DNA response element 5'-TGAGCTCA-3'. TPA, or 12-O-tetradecanoylphorbol-13-acetate is a phorbol ester, a potent tumor promoter known to activate the signal transduction protein kinase C (PKC) . PKC describes a family of protein kinase enzymes that are involved in controlling the function of other proteins through the phosphorylation of serine and threonine residues on those proteins.
    ::AP-1、活性蛋白1、活性蛋白1、活性蛋白1也是所查明的最早的转录因素之一;C-Fos是一种细胞原生蛋白;它属于素类拉链,包括细胞素、生长因子、压力、细菌和病毒感染,导致细胞过程改变,如分化、扩散和吸附。AP-1是由属于c-Fos、c-Jun、ATF和JDP家族的蛋白组成的杂交蛋白组成的。c-Fos是一种细胞原生蛋白;它属于素类的转录因子。 c-fo-fos基因产品通过乳素拉链与c-jun基因产品发生分裂,形成AP-1。AP-1激活含有TPADNA反应元素5'TGAGCTCA-3'的基因转录。TPA,或12O-tradetradecanecycyphylbol-13-aetate, 一种被称为激活信号感化蛋白质C(PKC),通过LC 控制这些蛋白质的蛋白质的蛋白质、PKC。

    ATF and JDP are two other classes of proteins that may dimerize with for or jun to form AP-1. ATF, activating transcription factor , is a class of AP-1 transcription factor dimers. JDP, or Jun dimerization protein is a member of the AP-1 family of transcription factors.
    ::ATF和JDP是另外两类蛋白质,可能与形成AP-1的分解或半分解。 ATF,即启动转录系数,是AP-1分录系数的类别。 JDP,或Jun dimer化蛋白是AP-1分录系数大家庭的成员。

    CCAAT-Enhancer-Binding Protein
    ::CCAAT-Enhancer-Binding 蛋白质

    CCAAT-enhancer-binding proteins , or C/EBPs form a family of transcription factors that bind to the CCAAT box motif. They are characterized by a highly conserved basic-leucine zipper (bZIP) domain, which is used to form protein dimers. C/EBPs are involved in different cellular responses, such as in the control of cellular proliferation, growth, and differentiation, and in metabolism and .
    ::C/EBP涉及不同的细胞反应,例如控制细胞扩散、生长和差异,以及新陈代谢和新陈代谢。

    c-Myc
    ::c-麦花

    Myc is a transcription factor that activates expression of many genes through binding to a specific cis-regulatory sequence. In the , Myc is believed to regulate expression of 15% of all genes through binding to Enhancer Box sequences (E-boxes) with the consensus sequence CANNTG. The myc family of transcription factors contain bHLH/LZ (basic Helix-Loop-Helix Leucine Zipper) domains. The myc protein, through its bHLH domain can bind to DNA, while the leucine zipper domain allows the dimerization with its partner,known as Max, another bHLH transcription factor. A mutated version of Myc is found in many cancers. The constitutive expression of the myc gene leads to excess myc protein and to the unregulated expression of many additional genes, some of which are involved in cell proliferation, resulting in the formation of .
    ::Myc 是一个通过特定Cis- 调控序列的约束激活许多基因表达的转录因子。 在Myc 中, Myc 据信通过与增强者盒序列(E-boxes)的绑定(E-boxes),通过协商一致序列CANNTG来调节所有基因的15%的表达方式。Myc 的缩略因子组含有 bHLH/LZ (基本 Helix-Loop-Helix Leucine Zipper) 域。 分子蛋白通过其 bHLH 域可以与DNA捆绑绑, 而 Leucine 拉链域允许与其伴侣(称为 Max ) 进行稀释, 另一个 bHLH 转录因子。 许多癌症中都发现了Myc 的变异版本 。 Myc 基因的构造表达方式导致超量的Mic蛋白质, 并导致许多其他基因的无节制表达方式, 其中一些基因与细胞扩散有关,导致形成。

    Summary
    ::摘要

    • Transcription factors are proteins that bind to regulatory elements on the DNA.
      ::归因是蛋白质,与DNA的监管要素相关联。
    • The TATA binding protein is one of the more common transcription factors, binding to the TATA box.
      ::TATA装订蛋白质是比较常见的转录系数之一,对TATA盒具有约束力。
    • DNA-protein interactions include conserved motifs, including the helix-loop-helix domain.
      ::DNA-蛋白质的相互作用包括保存的元素,包括螺旋-螺旋-螺旋-螺旋-helix域。
    • Sp1 and AP-1 are two of the original transcription factors identified.
      ::SP1和AP-1是确定的两个原始转录系数。

    Review
    ::回顾

    1. What is a transcription factor?
      ::什么是转录系数?
    2. Describe types of DNA-protein interactions.
      ::描述DNA-蛋白质相互作用的类型。
    3. Discuss three specific transcription factors.
      ::讨论三个具体的转录系数。
    4. When a homeodomain binds to DNA, the actual binding portion of the homeodomain is:
      1. A leucine zipper.
        ::麻风拉链
      2. The operon.
        ::礼服。
      3. Zinc fingers.
        ::锌指头
      4. The histine.
        ::刺纹。
      5. A helix-turn-helix motif.
        ::螺旋形转弯 螺旋形转弯

      ::当 homeodomain 与DNA连接时, homeodomain 的实际绑定部分是: Leucine 拉链, 食谱, Zinc 手指, 树枝, Helix- turn- helix mostif 。
    5. In the zinc fingers motif, the spacing of the helical segments is performed by:
      1. Beta sheets.
        ::贝塔床单
      2. Helical clusters.
        ::肝脏聚群
      3. Zinc atoms.
        ::锌原子
      4. Gamma helices.
        ::伽玛肝脏
      5. An alpha helix.
        ::阿尔法螺旋

      ::在锌手指motif, 螺旋段的间距由以下人员进行: Beta 床单、 Helical 团群、 Zinc 原子、 Gamma 螺旋、 Alpha 螺旋。