SUMO Regulation of mRNA Surveillance

mRNA 监测的 SUMO 调节

• 批准号: 7591705
• 负责人: Rachael S. Felberbaum
• 金额: $ 2.56万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7591705
• 关键词: Address; Aging; Alzheimer' s Disease; Animal Model; Cell Aging; Cell Nucleus; Cells; Defect; Disease; Eukaryotic Cell; Event; Excision; Genetic; Genetic Screening; Goals; Growth; Introns; Messenger RNA; Modification; Molecular; Nuclear Envelope; Pathway interactions; Peptide Hydrolases; Play; Positioning Attribute; Premature aging syndrome; Process; Progeria; Protein Fragment; Proteins; Quality Control; Regulation; Role; Saccharomyces cerevisiae; Saccharomycetales; Scheme; Syndrome; Testing; Translating; Ubiquitin; Ulp1 protease; Yeasts; age related; cell age; mRNA Export; mRNA Precursor; mRNA Surveillance; mutant; novel; prevent

DESCRIPTION (provided by applicant): Eukaryotic cells have multiple mechanisms to regulate mRNA quality. This regulation is generally altered in aged cells and is dysfunctional in several age-related diseases. In order to fully understand how mRNA regulation contributes to aging, a thorough understanding of the mechanisms of mRNA regulation is required. A new mRNA surveillance checkpoint has recently been identified in yeast that requires the SUMO protease Ulp1. SUMO (small ubiquitin related modifier) is a highly conserved small protein that is conjugated to many proteins throughout the cell. Modification by SUMO ("sumoylation") has a variety of effects that can be reversed by SUMO removal ("desumoylation") by the ULP SUMO proteases, including Ulpl The newly identified mRNA checkpoint prevents intron-containing pre-mRNAs from exiting the nucleus, where they can be translated into nonsense protein fragments that are toxic. The involvement of Ulp1 in this checkpoint suggests that desumoylation is a key process regulating this pathway. The broad objective of this project is to gain a molecular understanding of the mechanisms by which sumoylation and desumoylation regulate mRNA quality control. The findings from this study will identify new regulatory factors whose dysregulation likely contributes to aging. Using the budding yeast Saccharomyces cerevisiae as a model organism, two specific aims will be addressed. Aim 1 will characterize the roles of sumoylation and desumoylation in the pre-mRNA retention checkpoint by analyzing mutants defective for SUMO conjugation and removal to determine their requirement for preventing pre-mRNA export. In addition, double mutant analysis will be employed to establish a genetic scheme for pre-mRNA surveillance that positions the SUMO machinery with respect to other pathway components. The goal of Aim 2 is to identify sumoylated substrates involved in pre-mRNA surveillance and determine their regulatory significance in this pathway. Candidate substrate proteins will be screened for SUMO modification and tested to determine whether fusing SUMO to the protein can cause defective pre-mRNA retention. In addition, novel proteins involved in this pathway will be identified through a genetic screen for high-copy suppressors of a synthetic growth defect between an ulpl and an mRNA surveillance mutant. Relevance: Altered regulation of mRNA in the cell plays a role in aging and many age-related diseases, including Alzheimer's disease and the premature aging disease Hutchinson-Gilford Progeria Syndrome (HGPS). The goal of this project is to understand how a newly identified nuclear envelope-associated mechanism regulates mRNA. The results will thus provide new information regarding molecular events that likely contribute to aging and disease.

描述（由申请人提供）：真核细胞具有多种调节mRNA质量的机制。这种调节通常在老年细胞中改变，并且在几种与年龄有关的疾病中功能失调。为了充分了解mRNA调节如何导致衰老，需要对mRNA调节的机制进行透彻的理解。最近在酵母中发现了一个新的mRNA监视检查点，该检查点需要EMO蛋白酶ULP1。 Sumo（小型泛素相关的修饰剂）是一种高度保守的小蛋白，与整个细胞中的许多蛋白结合在一起。 Sumo（“ sumoylation”）的修饰具有多种效果，可以通过ULP Sumo蛋白酶（包括ULPL）逆转，通过ulpl（包括ULPL）逆转，新鉴定的mRNA检查点可以防止含有内含子内含子的前MRNA退出核，从而将其转化为废除蛋白质蛋白质蛋白质的质量有毒。 ULP1在此检查点中的参与表明Desumoylation是调节此途径的关键过程。该项目的广泛目的是对sumoylation和desumoylation调节mRNA质量控制的机制获得分子理解。这项研究的发现将确定其失调可能导致衰老的新调节因素。将使用酿酒酵母的芽酵母糖酵母作为模型生物，将解决两个具体的目标。 AIM 1将通过分析突变体在Sumo共轭和去除方面有缺陷以确定其防止前MRNA导出的要求，来表征Sumoylation和desumoylation在MRNA保留检查点中的作用。此外，将采用双重突变体分析来建立一种遗传方案，以实现MRNA前监测，该方案将相对于其他途径成分的Sumo机械定位。 AIM 2的目的是识别参与MRNA前监视的sumoyated底物，并确定其在该途径中的调节意义。候选底物蛋白将进行筛选进行SUMO修饰，并测试以确定将SUMO融合到蛋白质上是否会导致缺陷的MRNA保留。此外，将通过遗传筛选鉴定出参与该途径的新型蛋白质，以鉴定出ULPL和mRNA监测突变体之间合成生长缺陷的高拷贝抑制剂。 相关性：细胞中mRNA的调节改变在衰老和许多与年龄有关的疾病中起作用，包括阿尔茨海默氏病和早熟的衰老疾病Hutchinson-Gilford杂种综合征（HGPS）。该项目的目的是了解新确定的与核包膜相关的机制如何调节mRNA。因此，结果将提供有关可能导致衰老和疾病的分子事件的新信息。