{"title":"酿酒酵母中的转录沉默:已知的未知数","authors":"Namrita Dhillon, Rohinton T. Kamakaka","doi":"10.1186/s13072-024-00553-7","DOIUrl":null,"url":null,"abstract":"Transcriptional silencing in Saccharomyces cerevisiae is a persistent and highly stable form of gene repression. It involves DNA silencers and repressor proteins that bind nucleosomes. The silenced state is influenced by numerous factors including the concentration of repressors, nature of activators, architecture of regulatory elements, modifying enzymes and the dynamics of chromatin.Silencers function to increase the residence time of repressor Sir proteins at silenced domains while clustering of silenced domains enables increased concentrations of repressors and helps facilitate long-range interactions. The presence of an accessible NDR at the regulatory regions of silenced genes, the cycling of chromatin configurations at regulatory sites, the mobility of Sir proteins, and the non-uniform distribution of the Sir proteins across the silenced domain, all result in silenced chromatin that only stably silences weak promoters and enhancers via changes in transcription burst duration and frequency.These data collectively suggest that silencing is probabilistic and the robustness of silencing is achieved through sub-optimization of many different nodes of action such that a stable expression state is generated and maintained even though individual constituents are in constant flux.","PeriodicalId":49253,"journal":{"name":"Epigenetics & Chromatin","volume":"47 1","pages":""},"PeriodicalIF":4.2000,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Transcriptional silencing in Saccharomyces cerevisiae: known unknowns\",\"authors\":\"Namrita Dhillon, Rohinton T. Kamakaka\",\"doi\":\"10.1186/s13072-024-00553-7\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Transcriptional silencing in Saccharomyces cerevisiae is a persistent and highly stable form of gene repression. It involves DNA silencers and repressor proteins that bind nucleosomes. The silenced state is influenced by numerous factors including the concentration of repressors, nature of activators, architecture of regulatory elements, modifying enzymes and the dynamics of chromatin.Silencers function to increase the residence time of repressor Sir proteins at silenced domains while clustering of silenced domains enables increased concentrations of repressors and helps facilitate long-range interactions. The presence of an accessible NDR at the regulatory regions of silenced genes, the cycling of chromatin configurations at regulatory sites, the mobility of Sir proteins, and the non-uniform distribution of the Sir proteins across the silenced domain, all result in silenced chromatin that only stably silences weak promoters and enhancers via changes in transcription burst duration and frequency.These data collectively suggest that silencing is probabilistic and the robustness of silencing is achieved through sub-optimization of many different nodes of action such that a stable expression state is generated and maintained even though individual constituents are in constant flux.\",\"PeriodicalId\":49253,\"journal\":{\"name\":\"Epigenetics & Chromatin\",\"volume\":\"47 1\",\"pages\":\"\"},\"PeriodicalIF\":4.2000,\"publicationDate\":\"2024-09-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Epigenetics & Chromatin\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1186/s13072-024-00553-7\",\"RegionNum\":2,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GENETICS & HEREDITY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Epigenetics & Chromatin","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1186/s13072-024-00553-7","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GENETICS & HEREDITY","Score":null,"Total":0}
引用次数: 0
摘要
酿酒酵母中的转录沉默是一种持久而高度稳定的基因抑制形式。它涉及 DNA 沉默子和与核糖体结合的抑制蛋白。沉默状态受多种因素的影响,包括抑制因子的浓度、激活因子的性质、调控元件的结构、修饰酶和染色质的动态等。沉默因子的作用是增加抑制因子 Sir 蛋白在沉默结构域的停留时间,而沉默结构域的聚类可增加抑制因子的浓度,并有助于促进长程相互作用。在沉默基因的调控区域存在可访问的 NDR、调控位点染色质构型的循环、Sir 蛋白的流动性以及 Sir 蛋白在整个沉默域的非均匀分布,所有这些都导致沉默染色质只能通过改变转录爆发的持续时间和频率来稳定地沉默弱启动子和增强子。这些数据共同表明,沉默是概率性的,沉默的稳健性是通过对许多不同的作用节点进行次优化实现的,这样即使单个成分在不断变化,也能产生并维持稳定的表达状态。
Transcriptional silencing in Saccharomyces cerevisiae: known unknowns
Transcriptional silencing in Saccharomyces cerevisiae is a persistent and highly stable form of gene repression. It involves DNA silencers and repressor proteins that bind nucleosomes. The silenced state is influenced by numerous factors including the concentration of repressors, nature of activators, architecture of regulatory elements, modifying enzymes and the dynamics of chromatin.Silencers function to increase the residence time of repressor Sir proteins at silenced domains while clustering of silenced domains enables increased concentrations of repressors and helps facilitate long-range interactions. The presence of an accessible NDR at the regulatory regions of silenced genes, the cycling of chromatin configurations at regulatory sites, the mobility of Sir proteins, and the non-uniform distribution of the Sir proteins across the silenced domain, all result in silenced chromatin that only stably silences weak promoters and enhancers via changes in transcription burst duration and frequency.These data collectively suggest that silencing is probabilistic and the robustness of silencing is achieved through sub-optimization of many different nodes of action such that a stable expression state is generated and maintained even though individual constituents are in constant flux.
期刊介绍:
Epigenetics & Chromatin is a peer-reviewed, open access, online journal that publishes research, and reviews, providing novel insights into epigenetic inheritance and chromatin-based interactions. The journal aims to understand how gene and chromosomal elements are regulated and their activities maintained during processes such as cell division, differentiation and environmental alteration.