人类特异性调节DNA的丧失和人类特异性特征的演变
Cory Y McLean1, Philip L Reno, Alex A Pollen
1Department of Computer Science, Stanford University, Stanford, California 94305, USA.
Nature
|March 11, 2011
概括
人类进化涉及到特定的遗传变化,包括对保存的非编码DNA的删除. 这些关键基因附近的删除与人类特有的特征相关,例如大脑发育的改变和某些解剖特征的丧失.
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.
- 人类遗传学 人类遗传学
背景情况:
- 了解人类特异性特征的遗传基础对于进化研究至关重要.
- 非编码DNA中的调控元素在表型进化中起着重要作用.
- 之前的研究发现了人类加速序列变化和不同的基因表达.
研究的目的:
- 为了确定特定的分子事件,特别是保存的非编码区域的删除,这可能会推动人类特定的监管变化.
- 调查这些删除和人类进化适应之间的相关性.
主要方法:
- 比较基因组学:人类与其他哺乳动物 (如黑猩猩) 之间的全基因组比较.
- 在人类中识别被删除的序列,这些序列在其他哺乳动物中高度保存.
- 分析这些删除的位置和潜在的调节功能,重点是基因附近的非编码区域.
主要成果:
- 在人类中发现了510个对哺乳动物保存的序列的完全删除,主要是在非编码区域.
- 删除在参与类固醇激素信号传递和神经功能的基因附近进行了丰富.
- 特定的缺失与失去依赖于雄激素的感觉振动和阴茎棘 (在雄激素受体基因附近) 以及改变大脑区域扩张 (在GADD45G基因附近) 相关.
结论:
- 保存增强剂的完全删除是对人类进化有贡献的显著分子事件.
- 这些删除可以导致祖先特征的丧失和新特征的获得.
- 本研究提供了监管失活事件塑造人类分歧的具体例子.
相关概念视频
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...
Multi-species Conserved Sequences
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 DNA...
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
Evolution of Microbial Genome
Microbial genome evolution is a highly dynamic process shaped by continual gene gain and loss across species and strains. This genomic flexibility allows microorganisms to adapt rapidly to environmental pressures and interactions with other organisms. Central to understanding this diversity is the distinction between the core and pan genomes.The core genome comprises the genes shared by all sampled strains of a species, representing essential functions needed for fundamental cellular processes.
Genetic Drift
Natural selection—probably the most well-known evolutionary mechanism—increases the prevalence of traits that enhance survival and reproduction. However, evolution does not merely propagate favorable traits, nor does it always benefit populations.Life is not fair. A deer grazing contentedly in a field can have her meal cut tragically short by a bolt of lightning. If the doomed doe is one of only three in the population, 1/3 of the population’s gene pool is lost. Random events like this can...
Loss of Tumor Suppressor Gene Functions
Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...


