概括
具有相似活性位点的酶很可能是从单一的祖先酶进化出来的. 这项研究表明,含氨酸的酶起源于一种古老的含氨酸的酶,通过不同的进化途径.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 进化生物学 进化生物学
背景情况:
- 在DNA测序方面的进步导致了可用的测序数据的大量增加.
- 了解基因序列,蛋白质结构和功能之间的关系至关重要.
- 研究蛋白质进化可以揭示结构复杂性的洞察力.
研究的目的:
- 探索酶活性位点的进化起源.
- 研究线性基因序列与蛋白质功能之间的关系.
- 提出一种模型,用于从祖先的囊含有酶中演化含有血清素的活性位点.
主要方法:
- 对具有类似活性位点的酶进行比较序列分析.
- 基于序列数据的遗传学推断.
- 测试关于编码子类型之间的突变途径的假设.
主要成果:
- 确定了两种不同的进化系,它们的活性位点中含有必需氨酸残留的酶.
- 这些血统似乎源于一种古代酶,该酶在其活性部位中含有氨酸残留物.
- 进化差异的支持是假设通过单一突变不太可能发生特定的编码子变化.
结论:
- 这项研究提供了酶活性位点的不同演变的证据.
- 表明具有类似血清活性位点的酶具有共同的祖先起源.
- 突出了大规模序列数据在重建进化历史中的实用性.
相关概念视频
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In contrast, regions which code...
In contrast, regions which code...
Genome Size and the Evolution of New Genes
While every living organism has a genome of some kind (be it RNA, or DNA), there is considerable variation in the sizes of these blueprints. One major factor that impacts genome size is whether the organism is prokaryotic or eukaryotic. In prokaryotes, the genome contains little to no non-coding sequence, such that genes are tightly clustered in groups or operons sequentially along the chromosome. Conversely, the genes in eukaryotes are punctuated by long stretches of non-coding sequence.
Conservation of Protein Domains Over Different Proteins
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Synteny and Evolution
John H. Renwick first coined the term “synteny” in 1971, which refers to the genes present on the same chromosomes, even if they are not genetically linked. The species with common ancestry tend to show conserved syntenic regions. Therefore, the concept of synteny is nowadays used to describe the evolutionary relationship between species.
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
Gene Evolution - Fast or Slow?
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...


