Genetic Analysis of Genes Controlling a Position Effect

控制位置效应的基因的遗传分析

• 批准号: 8102034
• 负责人: JASPER D RINE
• 金额: $ 53.75万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 1982
• 资助国家: 美国
• 起止时间: 1982-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8102034
• 关键词: Acetylation; Adenosine Diphosphate Ribose; Affect; Animals; Award; Binding Sites; Bromodomain; Chromatin; Chromatin Structure; Chromosomes; Complement; Computer Analysis; Data; Development; Disease; Epigenetic Process; Folate; Folic Acid; Gene Expression; Gene Silencing; Genes; Genetic; Genetic Transcription; Genomics; Goals; Growth; Heterochromatin; Histone Deacetylase; Histone H3; Histones; In Vitro; Length; Link; Malignant Neoplasms; Measures; Methylation; Modeling; Modification; Molecular Chaperones; Nutritional; Nutritional status; O-Acetyl-ADP-Ribose; Plants; Positioning Attribute; Protein Biochemistry; Proteins; RNA Interference; Relative (related person); Research; Resolution; Role; Saccharomyces; Site; Suggestion; Testing; Variant; Work; Yeasts; base; comparative; fascinate; fitness; genetic analysis; in vivo; interest; nutrition; protein complex; protein structure; public health relevance; research study; segregation; transcription factor

DESCRIPTION (provided by applicant): The application is the first competitive review of the PI's MERIT award, during which much progress was made on gene silencing in Saccharomyces cerevisise. During this period, the genetic approaches that have been a strength of the lab have been complemented with new expertise in protein biochemistry, protein structure, genomics and computation. The three big goals of this research are: to understand how RNAi-independent gene silencing occurs leading to the formation of heterochromatin, how specialized structures of chromatin achieve their epigenetic inheritance, and how nutrition can affect epigenetic processes. On the mechanism of silencing, the PI proposes experiments to resolve the contradictory data from the Gross and Widom labs regarding how Sir proteins limit transcription factors' functions in heterochromatin. The NAD metabolite 2-0- Acetyl ADP Ribose, the product of the Sir2 histone deacetylase has gained much interest from in vitro suggestions for a role in silencing. The PI proposes three possible roles for the metabolite and critical in vivo tests of each role. Work on comparative silencing in related species has identified a Sir3 backup mechanism and provide a context that will allow testing of the growth versus oozing models for how heterochromatin spreads. Computational analysis of silencer sequences revealed a Rap1 binding site that is more conserved between species than are Rap1 binding sites within the same species. A hypothesis for this unprecedented conservation and a compelling test are proposed. With respect to the inheritance of the silenced state, a model is presented involving the segregation of Sir protein complexes on histone H3-H4 tetramers that makes specific quantitative predictions about how the stability of these silenced states should vary with the length of the silenced domain. An elegant test of the hypothesis is described that measures rates of change in heritable transcription states. In the recent past, the PI has uncovered links between H2A.Z acetylation, boundary function and the Bdf1 and Yta7 bromodomain proteins, which motivate experiments to uncover how chromatin boundaries function. Isotype-specific modifications and functions of the two H2Bs of yeast will be explored. Finally, the PI has uncovered a fascinating link between nutrition, in the context of folic acid, and heritable gene silencing through histone hypomethylation, whose mechanistic basis will be tested. PUBLIC HEALTH RELEVANCE: The inheritance of stable states of gene expression is relevant to the orderly development of all plants and animals and to the propagation of disease states such as cancer. Moreover, the link between nutritional status and epigenetic states is particularly important because 9% of people have two defective copies of a gene that, based upon the results here, are likely to impact heritable features on their chromosomes.

描述（由申请人提供）：申请是对PI优异奖的首次竞争综述，在此期间，在酿酒酵母中，基因沉默取得了很多进展。在此期间，实验室优势的遗传方法已与蛋白质生物化学，蛋白质结构，基因组学和计算方面的新专业知识相辅相成。这项研究的三个大目标是：了解无RNAI独立的基因沉默如何导致异染色质的形成，染色质的专业结构如何实现其表观遗传遗传以及营养如何影响表观遗传过程。关于沉默的机制，PI提出了实验，以解决有关SIR蛋白如何限制异染色质转录因子功能的总体和Widom实验室的矛盾数据。 NAD代谢产物2-0-乙酰基ADP核糖，Sir2组蛋白脱乙酰基酶的乘积已从体外建议中引起了人们对沉默中作用的兴趣。 PI提出了每个角色的代谢产物和关键体内测试的三个可能角色。相关物种中比较沉默的工作已经确定了SIR3备份机制，并提供了一种环境，可以测试生长与渗出模型的异染色质的扩散方式。消音器序列的计算分析揭示了一个Rap1结合位点，该位点比同一物种内的RAP1结合位点更保守。提出了这种前所未有的保护和引人入胜的测试的假设。关于沉默状态的遗传，提出了一个模型，其中涉及组蛋白H3-H4四聚体对SIR蛋白复合物的分离，该蛋白质复合物对这些沉默状态的稳定性如何随着沉默域的长度而变化，从而对这些沉默状态的稳定性做出了特定的定量预测。描述了对假设的优雅检验，该假设衡量了可遗传转录状态的变化速率。在最近的过去，PI发现了H2A.Z乙酰化，边界函数与BDF1和YTA7溴化域蛋白之间的联系，这激发了实验以发现染色质边界的功能。将探索两个酵母H2B的同种型特异性修饰和功能。最后，在叶酸的背景下，PI发现了营养之间的引人入胜的联系，并通过组蛋白低甲基化的基因沉默，其机械基础将进行测试。 公共卫生相关性：稳定的基因表达状态的遗传与所有动植物的有序发展以及疾病状态（如癌症）的传播有关。此外，营养状况与表观遗传状态之间的联系尤其重要，因为9％的人中有两个有缺陷的基因副本，基于这里的结果，可能会影响其染色体的可遗传特征。