两种烟草DNA结合蛋白与核因子CREB的同质性
1Laboratory of Plant Molecular Biology, Rockefeller University, New York 10021.
Nature
|August 31, 1989
概括
研究人员确定了两种烟草蛋白TGA1a和TGA1b,它们与特定的DNA序列 (as-1) 结合,这对于根基因表达至关重要. TGA1a是先前识别的ASF-1因子的强有力的候选者,解释了根特异性基因调节.
科学领域:
- 植物分子生物学 植物分子生物学
- 基因规则 基因规则
- 转录因子 转录因子
背景情况:
- 花马赛克病毒 (CaMV) 35S促进体含有一个重要的调节元件,as-1,负责根特异性基因表达.
- 之前已经确定了一种蛋白质因子,ASF-1,它与as-1结合,并与其 vivo 功能相关联.
研究的目的:
- 为了分离和描述与as-1序列结合的蛋白质.
- 确定ASF-1在调节根基因表达中的功能分子基础.
主要方法:
- 烟草补充DNA (cDNA) 克隆的分离,编码TGACG序列特定的结合蛋白.
- 对cDNA克隆的序列分析以确定蛋白质结构.
- 在体外结合测试以评估蛋白质-DNA相互作用.
主要成果:
- 从烟草中分离出两个TGA1a和TGA1b的TGACG序列特异性结合蛋白.
- 序列分析显示,TGA1a和TGA1b都具有与已知的转录因子同源的基本区域和氨酸-拉链域.
- TGA1a表现出与ASF-1因子一致的结合特异性,这表明它在as-1功能中的作用.
结论:
- TGA1a和TGA1b是与as-1调节元件结合的新型转录因子.
- TGA1a是ASF-1蛋白的强有力的候选者,通过as-1元素赋予的根特异性基因表达进行调解.
- 这些发现为植物根中的基因表达调节提供了分子洞察力.
相关概念视频
02:13Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
02:42Eukaryotic 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...
01:30General 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...
02:13Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...