固定的真核生物的基因组揭示了器官生成的替代途径
Sarah Frail1, Melissa Steele-Ogus2, Jon Doenier1
1Department of Biochemistry, Stanford School of Medicine, Stanford, CA 94305.
概括
在没有显著的遗传集成的情况下,在数百万年内保持有义务的蓝藻细菌内共生体 (亚亚质体). 这种最小的基因转移挑战了传统的有机细胞模型,并为生物工程新的内共生区提供了洞察力.
科学领域:
- 内生共生研究研究内生共生.
- 机体细胞的进化过程
- 海洋生物学 海洋生物学
背景情况:
- 内共生基因转移 (EGT) 和蛋白质进口被认为是稳定器官集成的关键.
- 较新的模型质疑器官发生过程中遗传集成的起源和时间.
- 体藻是宿主质体,它们是与固定性UCYN-A相关的有约束力的蓝藻内生生物.
研究的目的:
- 为了研究在Epithemia diazoplasts中遗传集成的程度.
- 为了比较两个不同的Epithemia物种 (E.clementina和E.pelagica) 的遗传融合.
- 评估观察到的基因转移和蛋白质进口的功能意义.
主要方法:
- 对Epithemia clementina和Epithemia pelagica的基因组分析.
- 检测被集成到宿主核基因组中的隔膜质DNA.
- 蛋白质组学分析以识别隔膜体内宿主编码的蛋白质.
主要成果:
- 在两种物种中都发现了遗传集成的最小证据.
- 非功能性的,碎片化的隔膜质DNA集成到E.clementina核基因组中.
- 在E. pelagica中没有检测到DNA或基因转移;在E. clementina diazoplasts中只发现了6种宿主蛋白.
结论:
- 尽管数百万年来基因的整合很少,但表皮细胞的隔离体作为完整的隔离体起作用.
- 这挑战了传统的有机体进化和融合模型.
- 隔膜质细胞作为内共生区的新生生物工程的蓝图.
更多相关视频
12:47Workflow Based on the Combination of Isotopic Tracer Experiments to Investigate Microbial Metabolism of Multiple Nutrient Sources
Published on: January 22, 2018
9.5K
07:26Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids
Published on: January 26, 2012
24.4K
相关概念视频
Inorganic Nitrogen Assimilation
104
Nitrogen is an essential element in biological systems, forming a crucial component of proteins, nucleic acids, and other cellular constituents. Many bacteria and archaea acquire nitrogen in the form of nitrate (NO₃⁻) or ammonia (NH₃), which are then assimilated into biomolecules through specific enzymatic pathways.Assimilatory Nitrate ReductionWhen nitrate enters the cell, it undergoes a two-step reduction process known as assimilatory nitrate reduction. Initially, the enzyme...
104
Export of Mitochondrial and Chloroplast Genes
3.8K
A eukaryotic cell can have up to three different types of genetic systems: nuclear, mitochondrial, and chloroplast. During evolution, organelles have exported many genes to the nucleus; this transfer is still ongoing in some plant species. Approximately 18% of the Arabidopsis thaliana nuclear genome is thought to be derived from the chloroplast’s cyanobacterial ancestor, and around 75% of the yeast genome derived from the mitochondria’s bacterial ancestor. This export has occurred...
3.8K
Non-nuclear Inheritance
21.7K
Most DNA resides in the nucleus of a cell. However, some organelles in the cell cytoplasm—such as chloroplasts and mitochondria—also have their own DNA. These organelles replicate their DNA independently of the nuclear DNA of the cell in which they reside. Non-nuclear inheritance describes the inheritance of genes from structures other than the nucleus.
21.7K
Eukaryotic Evolution
36.5K
The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the nucleus-first hypothesis, the ancestral prokaryote first evolved a membrane to enclose DNA and form the nucleus. Conversely, the mitochondria-first hypothesis suggests that the nucleus was formed after endosymbiosis of mitochondria.
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
36.5K
Comparing Mitochondrial, Chloroplast, and Prokaryotic Genomes
13.4K
The present-day mitochondrial and chloroplast genomes have retained some of the characteristics of their ancestral prokaryotes and also have acquired new attributes during their evolution within eukaryotic cells. Like prokaryotic genomes, mitochondrial and chloroplast genomes neither bind with histone-like proteins nor show complex packaging into chromosome-like structures, as observed in eukaryotes. Unlike mitotic cell divisions observed in eukaryotic cells, mitochondria and chloroplasts...
13.4K
Genome Size and the Evolution of New Genes
8.3K
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.
8.3K
