Imprinted SnoRNA Genes in the PWS deletion Region

PWS 缺失区域中的印记 SnoRNA 基因

• 批准号: 6897860
• 负责人: UTA FRANCKE
• 金额: $ 28.56万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6897860
• 关键词: Prader Willi syndrome; SDS polyacrylamide gel electrophoresis; Xenopus oocyte; cell line; chromosome aberrations; clinical research; fluorescent in situ hybridization; gene deletion mutation; gene expression; gene targeting; genetic transcription; genomic imprinting; human tissue; immunoprecipitation; laboratory mouse; messenger RNA; methylation; microarray technology; northern blottings; nucleic acid quantitation /detection; phenotype; polymerase chain reaction; protein localization; small nuclear RNA; tissue /cell culture; transfection

A human disease model for the study of genomic imprinting. Prader- Willi syndrome (PWS) is a complex neurodevelopmental disorder caused by the inactivation of deletion of imprinted, paternally expressed genes within 4 Mbp of chromosome band 15q11.2. The overall goals of this project are to determine the mechanisms of imprinting in the PWS region and to elucidate the genetic and pathophysiologic pathways that lead to the PWS phenotype that involves metabolic and behavioral changes such as growth deficiency and lack of appetite control. A recently discovered novel paternally expressed imprinted gene cluster in the PWS deletion region (PWCR1 in human and Pwcr1 in mouse) encodes small nucleolar RNAs (snoRNAs) with short conserved sequence elements, called C and D boxes (de Los Santos et al. Amer. J. Hum. Genet. 67:1067, 2000). PWCR1 and Pwcr1 are the first mammalian snoRNA genes that show imprinted expression. C/D box snoRNAs are conserved in all organisms and usually serve to direct the site-specific methylation of the ribose 2-hydroxyl group of specific nucleotides in rRNA., PWCR1/Pwcr1, belong to a novel class of snoRNAs, found mostly in brain, in which the sequences that would basepair with the target RNA are not complementary to any known rRNA or snRNA sequences. It is hypothesized that the modification target(s) of PWCR1snoRNAs are brain-specific mRNAs whose processes, such as alternative splicing, methylation or other modification, or intranuclear trafficking is controlled by binding to snoRNA-containing particles; and that lack of PWCR1 snoRNAs contributes to the hypothalamic dysfunction that causes the physical and behavioral manifestation of the PWS phenotype. The proposed work will characterize the organization, transcription, processing, localization and function of this novel kind of snoRNAs. Experimental strategies include the mining of the human genome for organization of the PWCR1snoRNA gene cluster, for a putative "host" gene for the PWCR1snoRNA genes and for candidate RNA modification targets. The expression patterns of putative target RNAs will be studied in the brain from PWS patients and in a PWS mouse model in which the Pwcr1 snoRNA cluster is deleted. PWCR1 snoRNAs will be tested for function by primer extension studies to detect 2'-O-methylation of synthetic complementary target RNAs. The work has the potential for discovery of novel RNA molecules that are modified as a result of a complex formation between PCR1snboRNPs and target RNA, and thus, for major breakthroughs in understanding the role of mRNA modification, and for innovation of new diagnostic and treatment modalities.

用于研究基因组印记的人类疾病模型。 Prader-Willi 综合征 (PWS) 是一种复杂的神经发育障碍，由染色体带 15q11.2 4 Mbp 内的印记、父系表达基因缺失失活引起。该项目的总体目标是确定 PWS 区域的印记机制，并阐明导致 PWS 表型的遗传和病理生理学途径，该表型涉及代谢和行为变化，例如生长不足和缺乏食欲控制。最近发现的 PWS 缺失区域中新的父系表达印记基因簇（人类中的 PWCR1 和小鼠中的 Pwcr1）编码具有短保守序列元件的小核仁 RNA（snoRNA），称为 C 和 D 盒（de Los Santos 等人，Amer. J. Hum. Genet. 67:1067, 2000）。 PWCR1 和 Pwcr1 是第一个显示印记表达的哺乳动物 snoRNA 基因。 C/D 盒 snoRNA 在所有生物体中都是保守的，通常用于指导 rRNA 中特定核苷酸的核糖 2-羟基基团的位点特异性甲基化。 PWCR1/Pwcr1 属于一类新型 snoRNA，主要在大脑中发现，其中与目标 RNA 碱基配对的序列与任何已知的 rRNA 或 snRNA 序列都不互补。据推测，PWCR1snoRNA 的修饰目标是大脑特异性 mRNA，其过程（例如选择性剪接、甲基化或其他修饰或核内运输）是通过与含有 snoRNA 的颗粒结合来控制的； PWCR1 snoRNA 的缺乏会导致下丘脑功能障碍，从而导致 PWS 表型的身体和行为表现。拟议的工作将描述这种新型 snoRNA 的组织、转录、加工、定位和功能。实验策略包括挖掘人类基因组以组织 PWCR1snoRNA 基因簇、寻找 PWCR1snoRNA 基因的假定“宿主”基因以及候选 RNA 修饰目标。将在 PWS 患者的大脑和删除了 Pwcr1 snoRNA 簇的 PWS 小鼠模型中研究推定靶标 RNA 的表达模式。 PWCR1 snoRNA 将通过引物延伸研究进行功能测试，以检测合成互补靶 RNA 的 2'-O-甲基化。这项工作有可能发现因 PCR1snboRNP 和靶 RNA 之间的复杂形成而被修饰的新型 RNA 分子，从而在理解 mRNA 修饰的作用方面取得重大突破，并创新新的诊断和治疗方式。

项目成果

Molecular breakpoint cloning and gene expression studies of a novel translocation t(4;15)(q27;q11.2) associated with Prader-Willi syndrome.

• DOI: 10.1186/1471-2350-6-18
• 发表时间: 2005-05-06
• 期刊: BMC medical genetics
• 作者: Schüle B;Albalwi M;Northrop E;Francis DI;Rowell M;Slater HR;Gardner RJ;Francke U
• 通讯作者: Francke U