在巨型肺鱼基因组的进化中自然选择的放松
Silvia Fuselli1, Samuele Greco2, Roberto Biello1
1Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy.
Molecular biology and evolution
|September 6, 2023
概括
大型动物的基因组,如肺鱼的基因组,可能是由于放松的选择而演变的. 这项研究发现了转录泄漏和肺鱼编码基因的放松选择的证据,这表明基因组扩张发生在一个几乎中立的场景中.
科学领域:
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
- 分子进化是分子进化的过程.
背景情况:
- 非适应性假设表明,当净化选择减弱时,基因组大小会扩大.
- 预计具有大型基因组的物种,如肺鱼,会表现出放松的选择.
- 这种预测的经验基因组证据有限.
研究的目的:
- 为了研究塑造肺鱼大型基因组的进化压力.
- 用基因组数据测试肺鱼中放松选择的假设.
- 探索转录调节和基因组大小演变之间的关系.
主要方法:
- 组装了澳大利亚肺鱼 (Neoceratodus forsteri) 的转录组.
- 分析了转录活动以寻找普遍转录或泄漏的证据.
- 进行了比较基因组分析,以检测肺鱼和其他脊椎动物编码基因中选择放松的特征.
主要成果:
- 肺鱼转录组显示过多的普遍转录,表明潜在的低于最佳的转录控制.
- 与其他脊椎动物相比,在肺鱼编码基因中观察到放松选择的显著特征.
- 这些发现支持了基因组扩张在放松的进化约束下发生的想法.
结论:
- 肺鱼最大的已知动物基因组的进化可能归因于一个几乎中立的进化场景.
- 削弱的净化选择和转录泄漏可能导致了肺鱼的基因组扩张.
- 这项研究为基因组大小进化的非适应性假设提供了经验性基因组支持.
相关概念视频
Gene Evolution - Fast or Slow?
7.2K
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...
7.2K
Speciation Rates
21.3K
Overview
21.3K
Multi-species Conserved Sequences
4.0K
Next-generation sequencing technologies have created large genomic databases of a variety of animals and plants. Ever since the human genome project was completed, scientists studied the genome of primates, mammals, and other phylogenetically distant living beings. Such large-scale studies have provided new insights into the evolutionary relationship between organisms.
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved...
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved...
4.0K
Limits to Natural Selection
31.4K
Organisms that are well-adapted to their environment are more likely to survive and reproduce. However, natural selection does not lead to perfectly adapted organisms. Several factors constrain natural selection.
31.4K
The Evidence for Evolution
42.9K
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
42.9K
Genome Size and the Evolution of New Genes
2.5K
2.5K


