ロボシグナルレベルによって制御される胎児における皮質神経生成の進化
Contact us if these videos are not relevant.
Contact us if these videos are not relevant.
PubMedで要約を見る
まとめ
この要約は機械生成です。進化の過程で脳が発達したことで 哺乳類の脳皮質が 膨らんだことが分かりました Slit/RoboとDll1という 重要な信号伝達経路が ニューロンの生成を制御し 胎児間での脳の複雑性の違いを 引き起こします
科学分野
- 発達生物学
- 進化生物学
- 神経科学
背景
- 脳皮質の大きさは爬虫類,鳥類,哺乳類によって大きく異なる.
- 哺乳類のニューロゲネシスの経路は知られているが,胎児の進化の起源は不明である.
研究 の 目的
- 胎児の脳皮質の発達における進化的差異の根底にある遺伝的およびシグナルメカニズムを調査する.
- 哺乳類の新皮質の拡張に 責任のある保存された信号経路を特定する.
主な方法
- 哺乳類,鳥類,爬虫類の古皮質と新皮質における神経生成の比較分析.
- マウス,チキ,ヘビの胚における機能の獲得と喪失の実験.
- 信号経路の役割を研究するために人間の脳器官を使用する.
主要な成果
- 放射性膠質からの直接的なニューロゲネシスは,すべての胎児細胞の古皮質を支配する. 基礎原始体経由の間接的なニューロゲネシスは,哺乳類の新皮質の特徴である.
- 高いSlit/Robo信号と低いDll1信号は,直接の神経生成に必要で十分である.
- 蛇や鳥のRoboとDll1シグナリングを調節すると,基礎原始細胞形成と間接的な神経生成が誘発される.
結論
- 哺乳類の新皮質の進化的拡大と複雑さは 保存された信号伝達経路の変化によって引き起こされます
- Slit/RoboとDll1のシグナリングの調節は,胎児の脳進化の重要なメカニズムを表しています.
関連する概念動画
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
The collection of fossils within sedimentary rocks give a record of common ancestry and often depicts the history of...
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...
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...
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...
In acid-base chemistry, the leveling effect refers to the limitation imposed by the solvent on the strength of acids and bases in solution. When a base stronger than the solvent's conjugate base is used, it deprotonates the solvent until the base is entirely consumed, making it ineffective against weaker acids. Conversely, an acid stronger than the solvent's conjugate acid protonates the solvent until the acid is depleted, rendering it ineffective against weaker bases. Essentially, the...
In the CNS, neurogenesis, the birth of new neurons from stem cells, is limited to the hippocampus in adults. In other regions of the brain and spinal cord, neurogenesis is almost non-existent due to inhibitory influences from neuroglia, especially oligodendrocytes, and the absence of growth-stimulating cues. The myelin produced by oligodendrocytes in the CNS inhibits neuronal regeneration. Furthermore, astrocytes proliferate rapidly after neuronal damage, forming scar tissue that physically...