测试基因的外子理论:来自蛋白质结构的证据
A Stoltzfus1, D F Spencer, M Zuker
1Department of Biochemistry, Dalhousie University, Halifax, Nova Scotia, Canada.
概括
基因的外基因理论,提出分裂的基因是由迷你基因 (外基因) 形成的,缺乏证据. 严格的分析发现外子和蛋白质结构单元之间没有显著的联系,挑战了这种基因进化理论.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 进化生物学 进化生物学
背景情况:
- 基因的外因子理论表明,分裂基因是从由间隔器 (内因子) 分隔的原始小基因 (外因子) 进化而来的.
- 之前的研究引用了外子和蛋白质结构单元之间的假定对应作为证据,但这还没有被严格证明.
- 内子和基因结构的起源仍然是分子进化的关键问题.
研究的目的:
- 客观地调查外子和蛋白质结构的离散单元之间的拟议对应.
- 通过使用定量方法,严格测试基因外子理论的有效性.
- 重新评估以前引用的证据支持外子子理论.
主要方法:
- 开发客观的方法来检测基因组和蛋白质结构元素之间的对应性.
- 将这些方法应用于以前用于支持外型子理论的四个具体例子.
- 统计分析以确定任何观察到的相关性的意义.
主要成果:
- 在分析的古代基因中,没有检测到外子和蛋白质结构的离散单元之间的统计学意义上的对应.
- 假设的联系,经常被引用作为对外子理论的证据,并没有被客观分析所证实.
- 这些发现挑战了关于基因进化的外子理论的基本前提.
结论:
- 基因的外基因理论,以目前的形式,没有证据支持.
- 外体和蛋白质结构单元之间缺乏一般的对应性表明,内部和基因进化的替代模型可能更准确.
- 需要进一步的研究来了解内核和分裂基因的进化起源.
相关概念视频
Organization of Genes
Overview
From DNA to Protein
The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of mRNAs, which in turn specify the sequence of amino acids making up all proteins. The decoding of one molecule to another is performed by specific proteins and RNAs. Because the information stored in DNA is so central to cellular function, it makes intuitive sense that the cell would make mRNA copies of this information for protein synthesis...
Conservation 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...
Proteins: From Genes to Degradation
Within a biological system, the DNA encodes the RNA, and the nucleotide sequence in the RNA further defines the amino acid sequence in the protein. This is referred to as “The Central Dogma of Molecular Biology” - a term coined by Francis Crick. Central dogma is a firm principle in biology that defines the flow of genetic information within any life form. The two fundamental steps in central dogma are - transcription and translation.
Transcription is the synthesis of RNA molecules by RNA...
Transcription is the synthesis of RNA molecules by RNA...
Exon 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...
Ribosome Profiling
Ribosome profiling or ribo-sequencing is a deep sequencing technique that produces a snapshot of active translation in a cell. It selectively sequences the mRNAs protected by ribosomes to get an insight into a cell’s translation landscape at any given point in time.
Applications of ribosome profiling
Ribosome profiling has many applications, including in vivo monitoring of translation inside a particular organ or tissue type and quantifying new protein synthesis levels.
The technique helps...
Applications of ribosome profiling
Ribosome profiling has many applications, including in vivo monitoring of translation inside a particular organ or tissue type and quantifying new protein synthesis levels.
The technique helps...


