Mechanisms of gene expression

基因表达机制

• 批准号: 10265850
• 负责人: rafael c casellas
• 金额: $ 414.55万
• 依托单位: NATIONAL INSTITUTE OF ARTHRITIS AND MUSCULOSKELETAL AND SKIN DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10265850
• 关键词: Affinity; Antibodies; Antigens; Architecture; Area; B-Lymphocytes; Biological Assay; CCCTC-binding factor; CRISPR/Cas technology; Cells; Collaborations; Cryoelectron Microscopy; DNA; DNA Repair Gene; DNA Sequence; Enhancers; Ensure; Enzymes; Fc Receptor; Frequencies; Gene Expression; Genes; Genetic Recombination; Genetic Screening; Genetic Transcription; Human Genome; Immune system; Individual; Infection; Laboratories; Lymphocyte; Manuscripts; Methods; Microscopy; Mutation; Nature; Nuclear; Paper; Polymerase; Process; Proteins; Publications; RNA; Receptor Gene; Regulator Genes; Regulatory Element; Reporting; Research; Resolution; Role; System; Techniques; Technology; Transcriptional Regulation; Visualization; cohesin; comparative genomics; genetic information; inhibitor/antagonist; mammalian genome; mouse genome; neural network; pathogen; promoter; recruit; transcription factor

Transcriptional regulation is the means whereby cells orchestrate expression of individual genes or group of genes. Recent studies with single cells have shown that, for the most part, transcription is not a continuous activity but it occurs in bursts. The amount of RNA produced for each gene is directly proportional to the amplitude and frequency of such bursts. How these two parameters are controlled is not totally clear, but it appears that DNA sequence information at promoters determine the amplitude, while burst frequencies rely on sequence information at enhancers. Promoters and enhancers are also known as gene regulatory elements. Their primary role is to recruit enzymes (polymerases) and other key proteins (transcription factors, activators and inhibitors) that open up the DNA helix and read the genetic information. Another important feature of promoters and enhancers is that to function properly they must either be in close proximity or in contact with each other. These interactions are not only important for gene expression, but as our laboratoratory and others have shown in the past 5 years, they are key to recombination of genes key for the immune system. This fiscal year, our laboratory has continue exploring how the cell facilitate contacts between regulatory DNA to drive transcription and recombination in lymphocytes. Key publications in this area: 1- Zhang et al. Nature, November 2019 and Ba et al. Nature, July 2020. In these manuscripts we have shown in collaboration with Fred Alt (Harvard) that recombination of antibody genes is driven by nuclear architectural proteins CTCF and cohesin. Their activity ensures that B cells express a broad range of antibody receptors with which pathogens are recognized during infection. 2- Senigl et al. Cell Reports, December 2019. In this manuscript we reported in collaboration with David Schatz (Yale) that nuclear architecture facilitates the mutation of antibody receptor genes. This process ensures that antigens (pathogens) are recognized with exquisite affinity during an infection. 3- Liu et al. Cell Research, April 2020. In this report we characterized the role of a DNA repair protein, known as ERCC6L2, in the resolution of DNA breaks intermediate to antibody gene recombination. 4- Xie et al. Nature Methods, April 2020. This paper reports a new microscopy technique that permits visualization of transcriptionally active domains in the mammalian genome.

转录调节是细胞编排单个基因或基因组的表达的手段。对单个细胞的最新研究表明，在大多数情况下，转录不是连续的活性，而是发生在爆发中。每个基因产生的RNA量与此类爆发的幅度和频率直接成正比。如何控制这两个参数并不完全清楚，但是看来启动子的DNA序列信息决定了幅度，而爆发频率依赖于增强子处的序列信息。启动子和增强子也称为基因调节元件。它们的主要作用是募集酶（聚合酶）和其他关键蛋白（转录因子，激活剂和抑制剂），以打开DNA螺旋并阅读遗传信息。启动子和增强剂的另一个重要特征是，要正常运作，它们必须处于近距离状态或彼此接触。这些相互作用不仅对基因表达很重要，而且正如我们的实验室和其他人在过去5年中所显示的那样，它们是免疫系统基因关键重组的关键。这个财政年度，我们的实验室继续探索细胞如何促进调节性DNA之间的接触以驱动淋巴细胞的转录和重组。 该领域的主要出版物： 1-张等。自然，2019年11月和BA等。自然，2020年7月。在这些手稿中，我们与弗雷德·阿特（Harvard）合作表明，抗体基因的重组是由核建筑蛋白CTCF和粘蛋白驱动的。它们的活性确保B细胞表达广泛的抗体受体，在感染过程中识别病原体。 2- Senigl等。细胞报告，2019年12月。在本手稿中，我们与David Schatz（耶鲁大学）合作报告了核结构促进了抗体受体基因的突变。该过程确保感染过程中抗原（病原体）具有精致的亲和力。 3-刘等。细胞研究，2020年4月。在本报告中，我们表征了DNA修复蛋白（称为ERCC6L2）在DNA断裂中的作用，这是抗体基因重组的中间。 4- Xie等。自然方法，2020年4月。本文报告了一种新的显微镜技术，该技术允许可视化哺乳动物基因组中的转录活性域。