概括
热冲击基因转录因子 (HSTF) 结合Drosophila hsp 70涉及多个上游站点的合作相互作用. 最大的基因激活需要在TATA近位点结合,但仅仅如此是不够的.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 德罗斯菲拉hsp 70基因是由热冲击基因特异转录因子 (HSTF) 调节的.
- HSTF结合发生在基因调节区域内的多个部位.
研究的目的:
- 为了研究HSTF在Drosophila hsp 70基因中的结合亲和和合作相互作用.
- 确定个别HSTF结合点在转录激活中的作用.
主要方法:
- 使用5'和3'删除突变进行足迹研究.
- 糖-烯胺凝试验以确定结合亲和力.
- 在体外转录测定与核提取物和复制实验.
主要成果:
- 在55bp域内确定了两个连续的HSTF结合位点,它们具有不同的内在亲和力,距离TATA同源性相近.
- 与较远的部位相比,HSTF对TATA近位部位的亲和力是12.5倍.
- 与远端部位的结合似乎是合作性的,取决于近端部位的占用.
结论:
- 塔塔附近的HSTF结合部位至关重要,但不足以实现最大的hsp 70基因转录激活.
- 对多个部位的HSTF的合作结合对于Drosophila中高效的热冲击基因调节至关重要.
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...
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...
Bacterial Transcription
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
General Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...


