原产地识别复合体,SIR1,以及对静音的S阶段要求
C A Fox1, A E Ehrenhofer-Murray, S Loo
1Department of Molecular and Cell Biology, Division of Genetics, 401 Barker Hall, University of California, Berkeley, CA 94720, USA.
概括
在Saccharomyces cerevisiae中,转录沉默涉及DNA复制. 原始识别复合体 (ORC) 和S相过渡对于沉默至关重要,其角色可以从复制启动中分离出来.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 在Saccharomyces cerevisiae中,转录沉默与DNA复制有关.
- 原始识别复合体 (ORC) 在DNA复制启动和转录沉默中发挥作用.
- 在HML和HMR位点建立静音要求通过S阶段.
研究的目的:
- 为了研究DNA复制和Saccharomyces cerevisiae中的转录沉默之间的关系.
- 确定ORC和S阶段在HML和HMR位置的沉默中的特定作用.
- 为了区分ORC在复制启动与转录沉默中的功能.
主要方法:
- 调查在不需要ORC的情况下对HMR静音的S相过渡的要求.
- 检查将Sir1蛋白与HMR-E消声器连接在一起对ORC依赖的消声器的影响.
- 评估ORC在端粒转录沉默中的Sir1独立作用.
主要成果:
- 通过S阶段是必要的HMR沉默,独立于ORC在复制启动中的作用.
- 在HMR静音器中对ORC的要求可以通过将Sir1与HMR-E静音器连接而绕过.
- 在端粒转录沉默中,ORC具有独特的,独立于Sir1的作用.
结论:
- 在转录沉默中ORC的作用是可以从其在DNA复制启动中的功能中分离的.
- 对于沉声来说,S相过渡是必不可少的,独立于沉声器的复制启动.
- 这些发现阐明了通过DNA复制过程影响基因沉默的独特机制.
相关概念视频
Inheritance of Chromatin Structures
Epigenetics is the study of inherited changes in a cell's phenotype without changing the DNA sequences. It provides a form of memory for the differential gene expression pattern to maintain cell lineage, position-effect variegation, dosage compensation, and maintenance of chromatin structures such as telomeres and centromeres. For example, the structure and location of the centromere on chromosomes are epigenetically inherited. Its functionality is not dictated or ensured by the underlying DNA...
Conservative Site-specific Recombination and Phase Variation
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
siRNA - Small Interfering RNAs
Small interfering RNAs, or siRNAs, are short regulatory RNA molecules that can silence genes post-transcriptionally, as well as the transcriptional level in some cases. siRNAs are important for protecting cells against viral infections and silencing transposable genetic elements.
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
S-Cdk Initiates DNA Replication
The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
S-Cdk Initiates DNA Replication
The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.


