概括
醇瘤促进剂,如TPA,激活蛋白激酶C以诱导早期的基因转录. 这项研究表明,TPA在人类细胞中特别增强了Simian virus 40 (SV40) 增强剂的活性,有助于转录因子的识别.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 癌症研究 癌症研究
背景情况:
- 醇瘤促进剂,如12-O-tetradecanoyl phorbol-13-acetate (TPA),诱导早期反应基因的转录 ("竞争力"基因,如c-myc和c-fos).
- 这些基因对于静止细胞进入细胞循环至关重要,它们的诱导由生长因子等因素介导,涉及蛋白激酶C激活.
- 识别由蛋白激酶C调节的转录因子是理解细胞对这些刺激的反应的关键.
研究的目的:
- 研究TPA诱导"能力"基因转录的机制.
- 为了确定由TPA激活的转录因子准的cis作用元素.
- 用一种特征化的系统来识别TPA调制的转作用因子.
主要方法:
- 使用了人类肝瘤细胞系.
- 评估了TPA对猿类病毒40 (SV40) 转录增强剂活性的影响.
- 专注于表征cis作用的转录控制元素.
主要成果:
- 证明TPA特别诱导人类肝瘤细胞中SV40转录增强剂的活性.
- 这种诱导表明,SV40增强剂作为TPA介导的转录调节的目标.
结论:
- SV40增强器系统为识别其活性被TPA修改的转录因子提供了有价值的工具.
- 这一发现有助于阐明TPA诱导的基因表达和细胞反应背后的分子机制.
相关概念视频
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...
Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
Cell Specific Gene Expression
Multicellular organisms contain a variety of structurally and functionally distinct cell types, but the DNA in all the cells originated from the same parent cells. The differences in the cells can be attributed to the differential gene expression. Liver cells, whose functions include detoxification of blood, production of bile to metabolize fats, and synthesis of proteins essential for metabolism, must express a specific set of genes to perform their functions. Gene expression also varies with...
Eukaryotic Transcription Activators
Transcription activators are proteins that promote the transcription of genes from DNA to RNA. In most cases, these proteins contain two separate domains ‒ a domain that binds to DNA and a domain for activating transcription; however, in some cases, a single domain is responsible for both binding and activation of transcription, as seen in the glucocorticoid receptor and MyoD.
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These domains are...
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These domains are...
Eukaryotic Transcription Inhibitors
Certain biochemical processes, such as embryonic development and cell growth regulation, depend on the repression of specific genes. DNA binding proteins known as eukaryotic transcription inhibitors regulate the repression of gene expression in eukaryotes. The presence of these inhibitors at the required location and time in the cell is triggered by the presence of hormones and additional signals from other cells.
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
TGF - β Signaling Pathway
The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...


