The Functions of the DEAD-Box RNA Helicase Has1 in 60S Ribosome Biogenesis

DEAD-Box RNA 解旋酶 Has1 在 60S 核糖体生物发生中的功能

• 批准号: 8201333
• 负责人: Jill Ann Dembowski
• 金额: $ 5.13万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8201333
• 关键词: ATP phosphohydrolase; Address; Alleles; Binding; Binding Sites; Biochemical; Biogenesis; Biological; Boxing; Cell Proliferation; Cells; Collection; Coupled; DNA Sequence Rearrangement; Defect; Detection; Development; Disease; Ensure; Environment; Eukaryota; Event; Exonuclease; Genetic Transcription; Global Change; Goals; Growth; Guanosine Triphosphate; Homologous Gene; Human; In Vitro; Light; Malignant Neoplasms; Messenger RNA; Metabolism; Methods; Molecular Genetics; Mutagenesis; Mutation; Normal Cell; Pathway interactions; Process; Protein Binding; Protein Biosynthesis; Proteins; Proteomics; RNA; RNA Binding; RNA Helicase; RNA Processing; RNA Splicing; RNA-Binding Proteins; Research; Ribonucleoproteins; Ribosomal Proteins; Ribosomal RNA; Ribosomes; Role; Saccharomyces cerevisiae; Scaffolding Protein; Small Nucleolar RNA; Staging; Techniques; Time; Translations; Yeasts; cell growth; cofactor; endonuclease; helicase; human disease; in vivo; insight; interest; mutant; nanomachine; neoplastic cell; overexpression; particle; prevent; protein function; rRNA Precursor; release factor; research study

DESCRIPTION (provided by applicant): Ribosomes are ubiquitous cellular nanomachines that enable decoding of mRNA and catalyze protein synthesis. Formation of functional ribosomes requires several pre-rRNA processing steps coupled with folding of the pre-rRNA and binding of ribosomal proteins to the rRNA. In humans, dysregulation of these processes leads to diseases related to alterations in normal cell growth and proliferation, including cancer. In recent years, the focus of the field has been to identify the factors involved in ribosome assembly and the specific steps in which they function. However, the exact roles of these proteins have been largely unstudied. These factors include exo- and endonucleases, GTP- and ATPases, RNA helicases, and RNA binding and scaffolding proteins. RNA helicases drive RNA-RNA, RNA-protein, and protein-protein rearrangements and are involved in all processes of RNA metabolism including transcription, splicing, and translation. In the yeast Saccharomyces cerevisiae, over half of the known RNA helicases function in ribosome biogenesis, consistent with this process being highly regulated and timed. The long-term goal of this project is to investigate the functions of the DEAD- box RNA helicase Has1 in 60S ribosome assembly. Using S. cerevisiae, combined genetic, molecular biological, biochemical, and proteomic approaches wil be carried out to address specific questions of Has1 function in two steps of the 60S ribosome assembly pathway. When does Has1 enter and exit preribosomes? Upon which factors does Has1 depend for recruitment into preribosomes? Which ribosomal proteins fail to stably associate with preribosomes when Has1 is depleted? Which assembly factors fail to enter or exit preribosomes when Has1 is depleted? What are the protein targets and cofactors of Has1? What are the RNA targets of Has1? In what local RNA environments does Has1 function? Answers to these questions will be valuable in understanding the exact functions of this protein in ribosome biogenesis and will shed light on more specific roles of RNA helicases in processes of RNA metabolism. Furthermore, because the pathway of ribosome assembly is highly conserved across eukaryotes, the proposed research plan will provide insight into how dysregulation of this process leads to human disease. PUBLIC HEALTH RELEVANCE: Both the Has1 helicase and the pathway of ribosome biogenesis are highly conserved across eukaryotes. Furthermore, the human homolog of Has1 is important for cell growth and its inhibition has been shown to prevent tumor cell proliferation. Therefore, understanding the functions of this helicase in yeast will have important implications in further study of human ribosome biogenesis and disease.!

描述（由申请人提供）：核糖体是普遍存在的细胞纳米机器，能够解码mRNA并催化蛋白质合成。功能性核糖体的形成需要几个前rRNA加工步骤，再加上前rRNA的折叠和核糖体蛋白与rRNA的结合。在人类中，这些过程的失调导致与正常细胞生长和增殖的改变相关的疾病，包括癌症。近年来，该领域的重点一直是确定参与核糖体组装的因子以及它们发挥作用的具体步骤。然而，这些蛋白质的确切作用在很大程度上尚未研究。这些因子包括核酸外切酶和核酸内切酶、GTP酶和ATP酶、RNA解旋酶以及RNA结合和支架蛋白。RNA解旋酶驱动RNA-RNA、RNA-蛋白质和蛋白质-蛋白质重排，并参与RNA代谢的所有过程，包括转录、剪接和翻译。在酵母酿酒酵母中，超过一半的已知RNA解旋酶在核糖体生物合成中起作用，这与该过程被高度调节和定时一致。该项目的长期目标是研究DEAD盒RNA解旋酶Has 1在60 S核糖体组装中的功能。利用S.酿酒酵母，联合遗传，分子生物学，生物化学和蛋白质组学的方法将进行解决的具体问题，Has 1功能的两个步骤的60 S核糖体组装途径。Has 1什么时候进入和离开前核糖体？Has 1依赖哪些因素募集到前核糖体中？当Has 1耗尽时，哪些核糖体蛋白不能与前核糖体稳定结合？当Has 1耗尽时，哪些组装因子不能进入或离开前核糖体？Has 1的蛋白质靶点和辅因子是什么？Has 1的RNA靶点是什么？Has 1在哪些局部RNA环境中发挥作用？这些问题的答案将是有价值的理解这种蛋白质在核糖体生物合成的确切功能，并将揭示RNA解旋酶在RNA代谢过程中的更具体的作用。此外，由于核糖体组装的途径在真核生物中高度保守，因此拟议的研究计划将深入了解这一过程的失调如何导致人类疾病。 公共卫生相关性：Has 1解旋酶和核糖体生物合成途径在真核生物中高度保守。此外，Has 1的人类同源物对于细胞生长是重要的，并且其抑制已被证明可以防止肿瘤细胞增殖。因此，了解该解旋酶在酵母中的功能将对进一步研究人类核糖体的生物合成和疾病具有重要意义。