从光保护到可塑性:在Chlamydomonas det1突变体中的转子子激活
Konomi Fujimura-Kamada1, Jun Minagawa1,2
1Department of Environmental Photobiology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, 444-8585, Japan.
The New phytologist
|August 7, 2025
概括
DE-ETIOLATED1 (DET1) 基因通常会抑制可移植元素 (TE). 一个缺乏DET1的突变者激活了TE,这破坏了压力反应并允许更快的生长,揭示了基因组可塑性和适应性之间的联系.
科学领域:
- 植物分子生物学 植物分子生物学
- 基因组学就是基因组学.
- 光合作用研究研究光合作用.
背景情况:
- 可转移元素 (TE) 是可驱动基因组适应的移动DNA序列,但通常被静止以保持基因组稳定性.
- DE-ETIOLATED1 (DET1) 是一个参与光信号和压力反应的基因,存在于Chlamydomonas reinhardtii.
- 由于构成性非光化学火 (NPQ),缺乏DET1的突变体表现出增强的高光耐受性,但这会损害低光 (LL) 中的生长.
研究的目的:
- 研究DET1在抑制可转移元素 (TE) 激活中的作用.
- 了解在低光 (LL) 条件下在det1突变体中观察到的快速回归到快速生长的表型背后的机制.
- 探索DET1介导的TE抑制,光保护和长期基因组适应之间的联系.
主要方法:
- 在不同的光照条件下对det1和抑制剂突变的表型分析.
- 包括基因表达研究在内的分子分析.
- 基因组分析,特别是可转移元素 (TE) 插入映射.
主要成果:
- 在LL条件下的det1突变体迅速演化了抑制突变,表明DET1在TE抑制中的作用.
- 发现一种名为"Bill"的特定TE可以插入调节光保护基因 (LHCSR1 / 3) 的转录因子复合体 (CrCO / NF-Ys) 的子单元.
- 这些法案插入破坏了构成性的NPQ,恢复了有效的光收获,并使LL的增长速度更快,解释了抑制器表型.
结论:
- DET1在抑制TE调动方面发挥着至关重要的作用,从而保持基因组完整性.
- TE激活,特别是通过Bill元素,可以覆盖工程应激反应 (构成性NPQ) 并促进适应.
- DET1作为一个关键环节,将短期光保护反应与长期基因组可塑性和适应策略相结合.
相关概念视频
Overview of Transposition and Recombination
16.1K
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
16.1K
Channel Rhodopsins
2.6K
Most organisms use photoreceptors to sense and respond to light. Examples of photoreceptors include bacteriorhodopsins and bacteriophytochromes in some bacteria, phytochromes in plants, and rhodopsins in the photoreceptor cells of the vertebral retina. The light-sensitive property of these receptors is because of the bound chromophores, such as bilin in the phytochromes and retinal in the rhodopsins.
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
2.6K
DNA-only Transposons
14.8K
DNA-only transposons are called autonomous transposons since they code for the enzyme transposase that is required for the transposition mechanism. Insertion of transposons can alter gene functions in multiple ways. They can mutate the gene, alter gene expression by introducing a novel promoter or insulator sequence, introduce new splice sites, and change the mRNA transcripts produced, or remodel chromatin structure.
The donor site from where the transposon is excised is either degraded or...
The donor site from where the transposon is excised is either degraded or...
14.8K
Protein Transport to the Inner Chloroplast Membrane
2.1K
Proteins targeted to the inner chloroplast membrane, or plastid proteins, are transported by two general pathways: the stop-transfer and the re-insertion or post-import pathways. Most plastid proteins carry N-terminal transit sequences and internal import sequences targeting it to the specific chloroplast subcompartment. Proteins targeted by the stop-transfer pathway have internal hydrophobic sequences that inhibit their translocation into the stroma. As a result, these precursors are arrested...
2.1K
Transposons
159
Transposons, or "jumping genes," are small mobile genetic elements (MGEs) that range from 700 to 40,000 base pairs in length. They are found in all organisms and can move within the same chromosome or transfer to different chromosomes. In some cases, transposons can also jump between different host DNA molecules, such as plasmids or viruses, contributing to genetic variability.Barbara McClintock first discovered these mobile genetic elements in the 1940s while studying maize genetics, and she...
159
Protein Transport to the Outer Chloroplast Membrane
2.0K
Chloroplast outer membrane proteins encoded by the nucleus are synthesized in the cytosol. Soon after synthesis, they bind cytosolic factors such as 14-3-3 protein and the Hsp70 chaperones that keep these precursors in an unfolded state until their translocation.
Two models describe the mechanism of precursor recognition and entry across the outer membrane through the TOC complex. Model 1 suggests the newly synthesized precursor binds to the TOC receptor 159 and forms a complex.
Two models describe the mechanism of precursor recognition and entry across the outer membrane through the TOC complex. Model 1 suggests the newly synthesized precursor binds to the TOC receptor 159 and forms a complex.
2.0K


