体轴的基因调节网络的进化通过增强器劫持在amphioxusus
Chenggang Shi1, Shuang Chen1, Huimin Liu1
1State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, China.
eLife
|January 17, 2024
概括
控制胚胎发育的基因调节网络 (GRNs) 在两动物中进化. 一个重复的基因,Gdf1/3-like,接管了Gdf1/3的轴向开发作用,可能是通过增强器劫持,创建了一个新的GRN.
科学领域:
- 进化发育生物学 进化发育生物学
- 进行比较的基因组学.
- 分子进化的分子进化.
背景情况:
- 基因调节网络 (GRNs) 调节胚胎发育.
- 节点信号通路,涉及节点,Gdf1 / 3和左侧,在双胞胎体的轴向模式中得到保留.
- 了解GRN进化机制对于破译发育生物学至关重要.
研究的目的:
- 为了研究头和弦状两动物 (cephalochordate amphioxus) 中的节点信号GRN的进化重新连接.
- 确定Gdf1/3及其复制品Gdf1/3-like在两骨轴发育中的作用.
- 阐明推动GRN演变的机制,特别是增强器劫持.
主要方法:
- 在两动物胚胎中对Gdf1/3和Gdf1/3相似的基因表达的比较分析.
- 对Gdf1/3和Gdf1/3-like的突变分析,以评估它们在轴向发育中的作用.
- 转基因记者试图检查Gdf1/3-like和Lefty之间的监管元素.
- 对Nodal进行母性突变分析,以评估其在轴向发育中的作用.
主要成果:
- 阿姆菲奥克斯Gdf1/3 ortolog显示最小的胚胎表达,而它的副本,Gdf1/3-like,是zygotically表达类似于Lefty.
- 类似Gdf1/3的突变体表现出轴向发育缺陷,而Gdf1/3突变体则没有.
- 在Gdf1/3-like和Lefty之间的基因间区域驱动记者基因表达,表明共享的调控控制.
- 节点在两病变中成为一种重要的母因子,母节点突变者表现出轴性缺陷.
结论:
- 类似Gdf1/3的基因在两动物的轴向发育中功能性取代了Gdf1/3的位置,这可能是通过左翼调节元件的增强器劫持.
- 这种GRN的重新连接,可能是由增强器劫持驱动的,代表了一个新的进化机制.
- 在Gdf1/3-like和Lefty之间共享的调节区域可能会赋予车身轴形成的稳定性,这可能解释发育系统漂移.
相关概念视频
02:02Cis-regulatory Sequences
9.9K
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
9.9K
02:24Regulation of Expression Occurs at Multiple Steps
3.0K
3.0K
02:32Exon 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
01:23Regulation of Expression at Multiple Steps
913
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the...
913
02:33Hedgehog Signaling Pathway
7.4K
The Hedgehog gene (Hh) was first discovered due to its control of the growth of disorganized, hair-like bristles phenotype in Drosophila, much like hedgehog spines. Hh plays a crucial role in the development of organs and the maintenance of homeostasis in both invertebrates and vertebrates. However, while Drosophila has only one Hh protein, mammals have multiple functional Hedgehog proteins - Sonic (Shh), Desert (Dhh), and Indian Hedgehog (Ihh). All of these homologous proteins have adapted to...
7.4K
02:23Master Transcription Regulators
6.9K
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
6.9K