在昆虫中转录抑制域的演化 霍克斯蛋白质
1Howard Hughes Medical Institute, University of Wisconsin, Madison 53706, USA.
Nature
|February 23, 2002
概括
同源性 (Hox) 基因调节动物的身体计划. 在Ultrabithorax (Ubx) 蛋白质中新发现的一种抑制域可能解释了昆虫多样性的演变.
科学领域:
- 发育生物学 发展生物学
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
背景情况:
- 同源性 (Hox) 基因对于动物体区域化至关重要.
- 霍克斯基因进化,包括重复,分歧和监管变化,有助于动物的多样性.
- 霍克斯蛋白在进化过程中获得新的蛋白质活动仍然在很大程度上未被探索.
研究的目的:
- 研究霍克斯蛋白是否在进化过程中获得了新的功能.
- 确定霍克斯蛋白中的新功能域,并评估它们的进化保护.
- 探索这些领域在动物形态的多样化中的潜在作用.
主要方法:
- 在Drosophila Ultrabithorax (Ubx) 蛋白中的功能域的识别和表征.
- 在不同关节动物和形动物血统中对Ubx Orthologues进行比较序列分析.
- 功能性测试用于确定已识别的域的活动.
主要成果:
- 在Drosophila Ubx.的carboxy-terminal区域中确定了一个转录抑制域.
- 这种压制域在其他昆虫的ubx正义中被保存.
- 该域在非昆虫关节动物和虫类动物的Ubx蛋白中不存在.
结论:
- 在Ubx中,碳氧末端抑制域的演化可能使昆虫的形态多样化更大.
- 这一发现表明,除了基因调节的变化之外,Hox蛋白功能的变化有助于进化多样化.
- 这项研究强调了探索蛋白质水平进化的重要性,以了解动物的多样性.
相关概念视频
02:26Conservation of Protein Domains Over Different Proteins
Protein domains are small structurally independent units that are part of a single amino acid chain. Although these domains are often structurally independent, they may rely on synergistic effects to perform their functions as part of a larger protein. Protein domains may be conserved within the same organism, as well as across different organisms.
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
02:36RNA 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...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
01:52Eukaryotic 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...
02:32Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...