泽斯特编码了一种特定序列的转录因子,该因子在体外激活了Ultrabithorax促进剂
M D Biggin1, S Bickel, M Benson
1Howard Hughes Medical Institute, Department of Biochemistry, University of California Berkeley 94720.
Cell
|June 3, 1988
概括
虫中的zeste蛋白与特定的DNA位点结合,并激活Ubx基因转录. 这一发现表明传导的机制,一个涉及配对染色体的过程.
科学领域:
- * 发育生物学 发育生物学
- * 分子遗传学 分子遗传学
- * 基因调节 基因调节
背景情况:
- * Zeste 是Drosophila melanogaster中的一个调节基因,对于 bithorax 综合体的转移至关重要.
- * 穿越是一种现象,在同质染色体上的等位基因相互影响对方的表达.
研究的目的:
- * 为了研究zeste蛋白调节转录的分子机制.
- * 为了确定zeste蛋白是否直接与Ultrabithorax (Ubx) 基因促进体结合并激活.
主要方法:
- *从多菌细胞和大肠杆菌中净化zeste蛋白质.
- *使用Ubx和Adh (酒精脱酶) 促进剂的体外转录试验.
- *对Ubx转录起点上游的zeste蛋白结合点的分析.
主要成果:
- * 纯化的zeste蛋白与位于UbxRNA启动部位的5'处的多个部位结合.
- *Zeste蛋白在体外激活了Ubx转录.
- * 激活取决于皮脂结合部位的存在;在突变的Ubx或Adh促进体中没有观察到激活.
结论:
- * 转载涉及在转录启动水平上起作用的调节元素.
- *Zeste介导的转录激活可能在机理上类似于增强器功能,但发生在配对的染色体上.
- *Zeste在调节Ubx和其他基因方面可能比以前理解的更重要.
更多相关视频
08:51Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling
Published on: June 25, 2015
06:21An Ecdysone Receptor-based Singular Gene Switch for Deliberate Expression of Transgene with Robustness, Reversibility, and Negligible Leakiness
Published on: May 7, 2018
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...
Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
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:
Repressible Operon: trp Operon
The trp operon in Escherichia coli exemplifies a repressible operon. It regulates the synthesis of tryptophan through repressor-mediated transcriptional control and attenuation. This dual regulatory mechanism ensures tryptophan biosynthesis occurs only when needed, conserving cellular resources.Structure of the trp OperonThe trp operon consists of five structural genes (trpE, trpD, trpC, trpB, and trpA) that encode enzymes for tryptophan biosynthesis. These genes are transcribed as a single...
Transcriptional Regulation: Riboswitches
Riboswitches are RNA elements that regulate gene expression by altering their secondary structures in response to specific effector molecules. These elements, located in the leader regions of certain mRNAs, act as transcriptional regulators by toggling between alternative conformations to control downstream gene expression. Riboswitch-mediated regulation is a precise mechanism for modulating biosynthetic pathways, as exemplified by the riboflavin biosynthesis pathway in Bacillus...
