相关实验视频
Updated: Jul 24, 2025

07:54
Manipulation of Ploidy in Caenorhabditis elegans
Published on: March 15, 2018
11.1K
菜的性别相关区域在一个很少重组的周心层区域内的演变
Hongbing She1, Zhiyuan Liu1, Shufen Li2
1State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Plant physiology
|July 5, 2023
概括
研究人员对菜的性别染色体进行了测序,以揭示Y染色体的起源. 一个特定于Y的区域可能源于重复的自身基因,影响了重组,导致Y染色体退化.
科学领域:
- 植物遗传学 植物遗传学
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
背景情况:
- 性染色体在不同的植物系中独立进化.
- 了解植物性决定和性染色体进化的遗传基础至关重要.
研究的目的:
- 描述西班牙菜 (Spinacia oleracea) X 和 Y 类型的参考基因组.
- 为了研究菜性染色体的进化起源和特征.
主要方法:
- 同性卵性XX (雌性) 和YY (雄性) 菜个体的测序.
- 对X和Y链接区域的比较基因组分析.
- 序列分歧的估计和基因含量和重复序列的分析.
主要成果:
- 在染色体4上确定一个13Mb的X链接区域 (XLR) 和一个24.1Mb的Y链接区域 (YLR).
- 有证据表明,Y特异性的"Y重复区域" (YDR) 来自自体内插入.
- YDR存在与侧边区域的重组减少相关;YLR表现出基因损失和重复序列增加的退化迹象.
结论:
- 菜Y染色体的起源是通过将自体序列重复到一个周周中心区域.
- 这一事件可能启动了Y染色体的重组抑制和随后的退化.
- 这些发现提供了关于植物性染色体进化的早期阶段的见解.
相关概念视频
Conservative Site-specific Recombination and Phase Variation
6.0K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
6.0K
Exon Recombination
3.6K
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...
3.6K
Gene Conversion
9.8K
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...
9.8K
Histone Variants at the Centromere
4.4K
Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3...
4.4K
Synteny and Evolution
3.3K
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...
3.3K
Crossing Over
147.2K
Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where each chromosome—replicated in S phase—is now composed of two sister chromatids (identical copies) joined centrally.
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process...
147.2K

