Regulation of Xist RNA processing in embryonic stem cells

胚胎干细胞中 Xist RNA 加工的调控

• 批准号: 7991959
• 负责人: BARBARA PANNING
• 金额: $ 28.39万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7991959
• 关键词: Affect; Antisense RNA; Binding; Biological Assay; Biological Models; Bypass; Cells; Chromatin Structure; Chromosomes; Complementary DNA; Complex; Coronary heart disease; DNA Structure; Data; Development; Diabetes Mellitus; Diagnosis; Disease; Elements; Ensure; Equilibrium; Fathers; Feedback; Female; Frequencies; Functional RNA; Gene Dosage; Gene Expression; Gene Expression Profile; Gene Expression Regulation; Genes; Genetic Transcription; Genome; Inherited; Learning; Link; Malignant Neoplasms; Molecular Biology; Mothers; Mutation; Parents; Play; Process; RNA; RNA Binding; RNA Processing; RNA Splicing; RNA Stability; Reading; Regulation; Regulator Genes; Role; Staging; Transcript; Translations; X Chromosome; X Inactivation; abstracting; embryonic stem cell; insight; male; mammalian genome; mutant; public health relevance; research study

DESCRIPTION (provided by applicant): ABSTRACT Non-coding RNAs with gene regulatory functions are starting to be seen as a common feature of mammalian gene regulation with the discovery that most of the transcriptome is non-coding RNA. Given that a significant proportion of the genome encodes non-coding RNAs, relatively little is known about the regulatory mechanisms and functions of these RNAs. Thus, new insights into how non-coding RNAs are regulated and how they regulate gene expression are essential for a complete understanding of mammalian gene expression. We employ X chromosome inactivation as a model system to study the regulation and function of non-coding RNAs. X-inactivation is the developmentally regulated transcriptional silencing of one X chromosome in female cells, used to equalize X-linked gene dosage with male cells. An antisense pair of non-coding RNAs, Xist and Tsix RNA, are central in the regulation of X-inactivation. X-inactivation is random - the X chromosome from each parent is silenced with equal frequency. Xist and Tsix RNA are expressed before the onset of X chromosome silencing and are necessary for X-inactivation to occur randomly. In Xist or Tsix mutant cells, X-inactivation is non-random and the fates of the mutant and the wild-type X chromosomes are fixed. Xist and Tsix mutations have opposite effects on X chromosome fate: an Xist mutant chromosome is always chosen as the active X and a Tsix mutant X chromosome is always chosen as the inactive X. Xist and Tsix also negatively regulate each other's expression, forming a feedback loop. In this proposal we dissect the Xist/Tsix feedback loop and explore how it is used to ensure that each X chromosome has an equal frequency of being silenced. PUBLIC HEALTH RELEVANCE: Project Narrative (Public Health Relevance) Non-coding RNAs play critical roles in regulating DNA structure, RNA expression, and translation, and thus affect normal development. While non-coding RNAs are already being identified as markers for cancer and associated with other complex diseases such as coronary disease and diabetes, little is understood about their regulation and function. A better understanding of non-coding RNAs will undoubtedly be important in the diagnosis and treatment of these conditions. We use X-inactivation as a model system to study the regulation and function of non-coding RNAs. In mammalian female cells, one X chromosome is silenced. This silencing ensures that X-linked gene dosage in XX female cells is equivalent to that in XY male cells. This process is essential for the survival of females. A pair of non- coding RNAs, Xist and Tsix RNA, is central in the regulation of X-inactivation. In this submission, we propose to study the regulation and function of Xist and Tsix RNA. What we learn will undoubtedly contribute to our understanding of X-inactivation, and more generally to the function of non-coding RNAs.

描述（由申请人提供）：摘要随着发现大多数转录组是非编码RNA，具有基因调控功能的非编码RNA开始被视为哺乳动物基因调控的共同特征。鉴于基因组的很大一部分编码非编码 RNA，人们对这些 RNA 的调控机制和功能知之甚少。因此，对非编码 RNA 如何调控以及它们如何调控基因表达的新见解对于全面了解哺乳动物基因表达至关重要。我们利用 X 染色体失活作为模型系统来研究非编码 RNA 的调控和功能。 X 失活是雌性细胞中一条 X 染色体的发育调节转录沉默，用于平衡雄性细胞中的 X 连锁基因剂量。一对反义非编码 RNA Xist 和 Tsix RNA 在 X 失活的调节中发挥着核心作用。 X 失活是随机的 - 来自每个亲本的 X 染色体以相同的频率沉默。 Xist 和 Tsix RNA 在 X 染色体沉默开始之前表达，并且是随机发生 X 失活所必需的。在 Xist 或 Tsix 突变细胞中，X 失活是非随机的，突变体和野生型 X 染色体的命运是固定的。 Xist 和 Tsix 突变对 X 染色体命运具有相反的影响：Xist 突变染色体始终被选为活性 X，Tsix 突变 X 染色体始终被选为非活性 X。Xist 和 Tsix 还相互负向调节彼此的表达，形成反馈环形。在本提案中，我们剖析了 Xist/Tsix 反馈循环，并探讨如何使用它来确保每个 X 染色体具有相同的沉默频率。 公共健康相关性：项目叙述（公共健康相关性） 非编码 RNA 在调节 DNA 结构、RNA 表达和翻译方面发挥着关键作用，从而影响正常发育。虽然非编码 RNA 已被确定为癌症标记物并与冠心病和糖尿病等其他复杂疾病相关，但人们对它们的调节和功能知之甚少。更好地了解非编码 RNA 无疑对于这些疾病的诊断和治疗非常重要。我们使用 X 失活作为模型系统来研究非编码 RNA 的调控和功能。在哺乳动物雌性细胞中，一条 X 染色体被沉默。这种沉默确保了 XX 雌性细胞中的 X 连锁基因剂量与 XY 雄性细胞中的相同。这个过程对于女性的生存至关重要。一对非编码 RNA，Xist 和 Tsix RNA，是 X 失活调节的核心。在本次提交中，我们建议研究 Xist 和 Tsix RNA 的调控和功能。我们所学到的知识无疑将有助于我们对 X 失活的理解，更广泛地有助于理解非编码 RNA 的功能。