Regulation of human telomerase

人端粒酶的调节

• 批准号: 10623683
• 负责人: JIYUE ZHU
• 金额: $ 38.25万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10623683
• 关键词: Aging; Alleles; Applications Grants; Bacterial Artificial Chromosomes; Cell Differentiation process; Cell Proliferation; Cell Survival; Chromatin; Chromosomes; Clustered Regularly Interspaced Short Palindromic Repeats; Compensation; DNA; Degenerative Disorder; Development; Disease; Distal; Elements; Elongation by Telomerase; Engineering; Enhancers; Enzymes; Funding; Gene Activation; Genes; Genetic Transcription; Genomics; Goals; HDAC4 gene; Homeostasis; Human; Introns; Laboratories; Malignant Neoplasms; Mediating; Methods; Molecular; Mus; Play; Pluripotent Stem Cells; Predisposition; RNA-Directed DNA Polymerase; Regulation; Regulatory Element; Reporter; Reporting; Repression; Role; Site; Somatic Cell; Specific qualifier value; TERT gene; Techniques; Telomerase; Transcriptional Regulation; age related; cancer cell; human disease; improved; in vivo; innovation; mouse model; recombinase; telomere; tool; transcription factor; Aging; Alleles; Applications Grants; Bacterial Artificial Chromosomes; Cell Differentiation process; Cell Proliferation; Cell Survival; Chromatin; Chromosomes; Clustered Regularly Interspaced Short Palindromic Repeats; Compensation; DNA; Degenerative Disorder; Development; Disease; Distal; Elements; Elongation by Telomerase; Engineering; Enhancers; Enzymes; Funding; Gene Activation; Genes; Genetic Transcription; Genomics; Goals; HDAC4 gene; Homeostasis; Human; Introns; Laboratories; Malignant Neoplasms; Mediating; Methods; Molecular; Mus; Play; Pluripotent Stem Cells; Predisposition; RNA-Directed DNA Polymerase; Regulation; Regulatory Element; Reporter; Reporting; Repression; Role; Site; Somatic Cell; Specific qualifier value; TERT gene; Techniques; Telomerase; Transcriptional Regulation; age related; cancer cell; human disease; improved; in vivo; innovation; mouse model; recombinase; telomere; tool; transcription factor

Abstract Our long-term goal is to decipher the molecular mechanisms of telomerase regulation and telomere homeostasis during development. Telomerase elongates telomeres to compensate for their loss during cell proliferation. Its regulation is critical for human aging and susceptibilities to cancer and many age-related degenerative diseases. The TERT gene, encoding the human telomerase reverse transcriptase, is regulated primarily at the level of transcription. It is highly expressed in pluripotent stem cells, but stringently repressed in most somatic cells. Recent progresses on telomerase regulation in cancer cells have greatly improved our understanding of TERT gene activation during cancer development. However, the mechanisms of its repression in most differentiated cells and expression in certain somatic cells remain to be elucidated. Regulation of transcription during development and differentiation often involves distal elements and chromatin reorganization. We previously reported that the endogenous TERT gene was embedded in a condensed chromatin domain and stringently repressed in a histone deacetylase-dependent manner in somatic cells. To identify distal regulatory sequences required for establishing the repressive chromatin of the TERT locus and to understand its regulation in vivo, our laboratory has developed two innovative technical platforms in the past decade. The first is recombinase-mediated BAC targeting or RMBT method, for targeted integration of single-copy BAC reporters into specified chromosomal sites. This technique, together with the new CRISPR-mediated gene editing, enables us to study distal regulatory elements of the TERT gene in their genomic contexts. Consequently, we have discovered that a polymorphic tandem DNA repeat in intron 2 (VNTR2-1) functions as an enhancer for TERT transcription. In addition, we have engineered a humanized mTert allele (hmTert) for studying human-specific telomerase regulation in mice. In the next funding period, we plan to use these tools and focus on the following three directions: (1) Identify transcription factors that regulate TERT gene via VNTR2-1; (2) Identify key distal regulatory elements responsible for TERT repression; and (3) Study the roles of these distal elements in regulating telomere homeostasis in vivo using our mouse model with humanized telomeres. In short, using our unique tools, we will address some of the fundamental mechanisms critical to telomerase regulation and telomere homeostasis in humans, and ultimately telomere-associated human diseases.

抽象的 我们的长期目标是破译端粒酶调节和端粒的分子机制 发展过程中的体内平衡。端粒酶拉长端粒以补偿其在细胞中的损失 增殖。它的调节对于人类衰老和对癌症的敏感性和许多与年龄有关的调节至关重要 退化性疾病。编码人端粒酶逆转录酶的TERT基因受调节 主要处于转录水平。它在多能干细胞中高度表达，但在 大多数体细胞。癌细胞中端粒酶调节的最新进展已大大改善了我们的 了解癌症发展过程中TERT基因激活。但是，其镇压的机制 在大多数分化的细胞中，某些体细胞中的表达仍有待阐明。调节 发育和分化过程中的转录通常涉及远端元素和染色质重组。 我们先前报道说，内源性TERT基因被嵌入在凝结的染色质结构域中，并且 在体细胞中以组蛋白脱乙酰基酶依赖性方式严格抑制。确定远端调节 建立TERT基因座的抑制性染色质所需的序列并了解其调节 在体内，我们的实验室在过去十年中开发了两个创新的技术平台。第一个是 重组酶介导的BAC靶向或RMBT方法，用于单拷贝BAC报告基因的靶向整合 进入指定的染色体位点。该技术以及新的CRISPR介导的基因编辑可以启用 美国在基因组中研究TERT基因的远端调节元件。因此，我们有 发现内含子2（VNTR2-1）中的多态串联DNA重复起到TERT的增强剂 转录。此外，我们已经设计了人源化的MTERTERELERELER（HMTERT）来研究人类特异性 小鼠的端粒酶调节。在下一个资金期间，我们计划使用这些工具并专注于以下 三个方向：（1）确定通过VNTR2-1调节TERT基因的转录因子； （2）识别远端密钥 负责TERT镇压的监管因素； （3）研究这些远端元素在 使用人源端粒的小鼠模型来调节体内端粒稳态。简而言之 独特的工具，我们将解决对端粒酶调节至关重要的一些基本机制和 人类中的端粒稳态，最终是与端粒相关的人类疾病。