在Cannabaceae家族中的子端粒卫星的对比图案
Lucie Horáková1,2, Václav Bačovský1, Radim Čegan1
1Department of Plant Developmental Genetics, Institute of Biophysics of the Czech Academy of Sciences, Brno, Czechia.
Frontiers in plant science
|September 5, 2025
概括
在Cannabaceae物种中卫星DNA (satDNA) 显示HSR1和HJSR重复的共同起源,而CS-1显示分歧. 这些发现揭示了家族中的卫星DNA进化和型动态.
科学领域:
- 植物基因组学
- 分子进化
- 细胞遗传学
背景情况:
- 卫星DNA (satDNA) 包含植物基因组中快速演变的重复序列.
- 卫星DNA对于理解染色体结构,进化和物种分化至关重要.
- 之前的研究在Cannabaceae中发现了特定的satDNA元素 (CS-1,HSR1,HJSR),但它们的进化历史尚不清楚.
研究的目的:
- 研究CS-1,HSR1和HJSR卫星DNA元素的进化起源和序列变异.
- 确定这些satDNA重复的跨物种染色体定位模式.
- 提供关于香草家族内卫星DNA动态和型进化的见解.
主要方法:
- 对CS-1,HSR1和HJSRsatDNA元素进行序列相似性分析.
- 使用现场化 (FISH) 进行跨种类染色体映射.
主要成果:
- HSR1和HJSR的satDNA元素在研究的Cannabaceae物种中得到保存和共享,这表明它们具有共同的祖先起源.
- 与HSR1和HJSR相比,CS-1 satDNA元素呈现出显著的序列分歧.
- 虽然主要是亚端粒,但所有三种satDNA元素都显示了特定物种的局部化模式.
结论:
- 共有的HSR1和HJSR重复表明在祖先的Cannabaceae血统中有一个共同的satDNA池.
- 在CS-1的序列分歧突出了家族内部正在进行的satDNA演变.
- 这些发现增强了我们对卫星DNA进化的理解,并支持了Humulus物种的分歧.
相关概念视频
02:04Polytene Chromosomes
10.2K
Polytene chromosomes are giant interphase chromosomes with several DNA strands placed side by side. They were discovered in the year 1881 by Balbiani in salivary glands, intestine, muscles, malpighian tubules, and hypoderm of larvae Chironomus plumosus. Hence, these are also called "Salivary gland chromosomes." These are found in insects of the order Diptera and Collembola; in certain organs of mammals; and synergids, antipodes of flowering plants. Polytene chromosomes are also...
10.2K
02:02Cis-regulatory Sequences
10.1K
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...
10.1K
03:40Introduction to Seed Plants
62.8K
Most plants are seed plants—characterized by seeds, pollen, and reduced gametophytes. Seed plants include gymnosperms and angiosperms.
62.8K
01:51Lampbrush Chromosomes
8.0K
In 1882, Flemming observed lampbrush chromosomes (LBC) in salamander eggs. Later in 1892, Rückert observed LBCs in shark egg cells and coined the term "lampbrush chromosomes" because they looked like brushes used to clean kerosene lamps.
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops...
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops...
8.0K
02:30Histone Variants at the Centromere
4.5K
Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3...
4.5K
01:21Frequency-dependent Selection
22.2K
When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.
22.2K