逆转换事件塑造了灵长类动物中ATAXIN-3基因家族的演变
相关实验视频
Updated: Mar 14, 2026

11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
8.8K
Daniela Felício1,2,3, Maria Inês Martins2, Andreia Pinto2
1Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal.
Genome biology and evolution
|March 12, 2026
概括
研究人员发现了马查多-约瑟夫病基因ATXN3的新类型,探索了它们的进化历史和新疗法的潜力. 这项研究揭示了脊髓小脑缩症中有毒重复扩张的起源.
科学领域:
- 进化遗传学的进化遗传学
- 神经退行性疾病的神经退行性疾病
- 分子生物学分子生物学
背景情况:
- 多聚氨胺脊髓脑动症 (SCAs) 是一种神经退行性疾病,与特定基因中的扩大CAG重复有关.
- 马查多-约瑟夫病 (MJD/SCA3),最常见的SCA,是由ATXN3基因的突变引起的,目前缺乏有效的治疗方法.
- 疾病相关基因的对应基因可以提供有关疾病机制和潜在治疗策略的见解.
研究的目的:
- 确定和描述涉及MJD/SCA3.3的ATXN3基因的新类型.
- 通过遗传学分析,研究ATXN3同类物种的进化史和功能潜力.
- 探索ATXN3对象对了解MJD/SCA3的致病机制和开发新疗法的相关性.
主要方法:
- 在灵长类动物进化过程中识别ATXN3逆转换事件.
- 对ATXN3及其对应物 (ATXN3L1,ATXN3L2,ATXN3L0,ATXN3L3) 的遗传学分析.
- 对基因序列,保存模式和 (CAG) n中断模式进行比较分析.
主要成果:
- 除了以前已知的ATXN3L1.1,还发现了三个新的ATXN3对应物 (ATXN3L0,ATXN3L2,ATXN3L3).
- 在灵长类动物中,ATXN3和ATXN3L1保留,显示出显著的氨基酸同一性和保存的约瑟芬域,表明功能冗余.
- ATXN3L2与ATXN3具有很高的核酸相似性,可能产生调节性RNA,而ATXN3L0和ATXN3L3在人类中可能是非功能性的或不存在的.
- 对 (CAG) n中断模式的分析阐明了人类ATXN3.3中病原性重复路径的演变.
结论:
- 发现ATXN3对应物的发现为了解MJD/SCA3病原体提供了新的途径.
- 保存的ATXN3L1表明通过模仿其功能来进行治疗干预的潜力.
- 对ATXN3同类物种的基因分析提供了对致病重复扩张的起源的见解,并有助于寻找向治疗方法.
相关概念视频
Exon Recombination
4.3K
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...
Exon shuffling follows “splice frame rules.” Each exon...
4.3K
Retroviruses
15.6K
Retroviruses and retrotransposons both insert copies of their genetic elements into the genome of the host cell. Thus, the viral genes are passed on when the host genome is replicated or translated. A typical retroviral DNA sequence contains 3-4 genes that encode the different proteins required for its structural assembly and function as a molecular parasite. This DNA is transcribed into a single mRNA, which is very similar in structure to conventional mRNAs, i.e., it is capped at the 5’...
15.6K
Overview of Transposition and Recombination
20.1K
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
20.1K
Synteny and Evolution
3.9K
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...
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral...
3.9K
LTR Retrotransposons
20.2K
LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
20.2K
Non-LTR Retrotransposons
13.8K
As the name suggests, non-LTR retrotransposons lack the long terminal repeats characteristic of the LTR retrotransposons. Additionally, both LTR and non-LTR retrotransposons use distinct mechanisms of mobilization. Non-LTR retrotransposons are further divided into two classes - Long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs), both of which occur abundantly in most mammals, including humans. Some of the active non-LTR retrotransposons in humans are L1...
13.8K

