セファロコルダトにおける軸のパターンと,オーガナイザーの進化
Jr-Kai Yu1, Yutaka Satou, Nicholas D Holland
1Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, California 92037-0202, USA.
Nature
|January 24, 2007
まとめ
ガストルア・オーガナイザーの進化的起源が調査されました. Amphioxusの胚は,背面/腹面および前/後軸のパターンのための保存された遺伝子発現パターンを示し,先祖のコルダ特性を示唆しています.
科学分野:
- 発達生物学 発達生物学とは
- 進化生物学の進化生物学について
- コルダトの胚形成について
背景:
- ガストルア・オーガナイザーは,脊椎動物の軸軸パターニングに不可欠です.
- 進化の歴史とオーガナイザーの起源は,ほとんど不明のままです.
- 早期の状体の発達を理解することは,脊椎動物の進化についての洞察を提供します.
研究 の 目的:
- ガストルア・オーガナイザーの進化的起源を調査する.
- アンフィオクサスにおける軸パターニングに関連する遺伝子発現パターンを調べる.
- アンフィオクサスと脊椎動物間のD/VとA/Pパターニングメカニズムを比較する.
主な方法:
- Amphioxus gastrulae.の背側/腹側 (D/V) と前側/後側 (A/P) の遺伝子発現パターンの分析.
- アンフィオクサス胚における外来骨型遺伝子タンパク質 (BMP) を用いた実験操作.
- 遺伝子発現データを,既知の脊椎動物のオートロジックと比較する.
主要な成果:
- Amphioxus gastrulaeは,脊椎動物に似たD/Vパターン遺伝子発現 (BMPs, Nodal) を表している.
- 外因的なBMP治療は,脊椎動物の反応を反映して,アンフィオックススの胚を腹部化します.
- Wnt-antagonistsとWnt遺伝子は,それぞれ前後表現が保存されていて,A/Pパターニングの役割を示しています.
結論:
- 初期の胃細胞におけるD/VおよびA/Pパターンのメカニズムは,コード動物全体で進化的に保存されています.
- セファロコルダ類 (アンフィオクサス) は,保存されたパターンの遺伝子発現と反応を持っています.
- D/VとA/P軸のパターンのための分離したシグナルセンターは,祖先の状動物特性を表す可能性があります.
関連する概念動画
01:54Convergent Evolution
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.The structures that arise from convergent evolution are called analogous structures. They are similar in function even if they are dissimilar in structure. Further, structures can be analogous while also...
02:05Gene Evolution - Fast or Slow?
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
02:54Evolutionary Relationships through Genome Comparisons
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
02:31Synteny 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...
02:05Gene Evolution - Fast or Slow?
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
01:24Evolution 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...