基因网络的进化是脊椎动物中发育基因形成的基础
Baubak Bajoghli1, Narges Aghaallaei, Isabell Hess
1Department of Developmental Immunology, Max-Planck Institute of Immunobiology, Stuebeweg 51, D-79108 Freiburg, Germany.
Cell
|June 30, 2009
概括
适应性免疫在脊椎动物中通过古老遗传网络的扩张而演变,结合了用于胸腺发育和T细胞特异性的新基因. 这个过程涉及新的信号通路,对免疫系统进化至关重要.
科学领域:
- 进化免疫学的进化免疫学
- 进行比较的基因组学.
- 发育生物学是发展生物学.
背景情况:
- 适应性免疫防御在大约5亿年前的脊椎动物中出现.
- 这种出现与像胸腺这样的创新有关,引发了关于其起源的问题:de novo或古代网络的详细阐述.
研究的目的:
- 为了重建基因变化背后的thymopoiesis (胸腺发育).
- 调查关键的适应性免疫特征是从古老的遗传网络进化出来的,还是从新出现的.
主要方法:
- 在带动物和基底脊椎动物之间进行比较基因组和表达分析.
- 在骨鱼中实验验证衍生基因网络模型.
主要成果:
- 在没有的脊椎动物的喉上皮质中,祖先网络在软骨鱼中扩展,结合了化学基因基因.
- 的脊椎动物中的淋巴细胞进化出了用于化学受体表达的新网络.
- 互补的变化促进了T细胞谱系规范的Delta/Notch信号传递.
结论:
- 脊椎动物的适应性免疫系统是通过古代遗传网络的阐述而进化的,而不是新的创造.
- 通过比较和实验方法,阐明了胸膜形成和T细胞发育的进化框架.
相关概念视频
Genetics of Speciation
Speciation is the evolutionary process resulting in the formation of new, distinct species—groups of reproductively isolated populations.
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...
Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
Multipotency of Hematopoietic Stem Cells
The hematopoietic stem cells or HSCs are multipotent, meaning they can differentiate and give rise to all blood and immune cells. HSCs are maintained in the quiescent stage until an external stimulus initiates their differentiation. The multipotent HSCs exist as two heterogeneous populations, long-term repopulating cells (LTRC) and short-term repopulating cells (STRC). The two HSC populations have different surface markers or receptors and are classified based on quiescence and long-term...
Primary Lymphoid Organs
Primary lymphoid organs are pivotal in the formation, development, and maturation of lymphocytes, the white blood cells that serve as the backbone of our immune system. This crucial function underscores their fundamental role in maintaining our overall health and immunity. The two primary lymphoid organs of prime importance are the red bone marrow and the thymus.
The red bone marrow is a soft, spongy tissue nestled in the interior of long bones such as the humerus and femur. It is the site...
The red bone marrow is a soft, spongy tissue nestled in the interior of long bones such as the humerus and femur. It is the site...
Evolution of New Traits in Microbes
Microorganisms evolve rapidly due to their large population sizes and short generation times, often exhibiting measurable changes within days under laboratory conditions. Natural selection acts on standing genetic variation, enabling the retention and amplification of beneficial traits that confer fitness advantages in changing environments.Adaptive Pigment Regulation in RhodobacterIn Rhodobacter, a genus of purple non-sulfur bacteria, light-harvesting pigments such as bacteriochlorophyll and...


