染色体对有益基因的捕获驱使等离子体走向生态冗余
R Craig MacLean1,2, Cédric Lood1, Rachel M Wheatley3,4
1University of Oxford, Department of Biology, 11a Mansfield Rd., Oxford OX1 3SZ, United Kingdom.
The ISME journal
|May 11, 2025
概括
在Rhizobium leguminosarum中,塑体上有益的基因是罕见的. 进化过程有利于将这些基因转移到细菌染色体中,随着时间的推移减少了等离子体的价值.
科学领域:
- 细菌遗传学和进化研究
- 微生物共生是微生物的共生.
- 等离子体生物学
背景情况:
- 塑体在细菌中很常见,但基因关联的原因尚不清楚.
- 了解等离子体染色体基因动态对于微生物进化至关重要.
- 植物共生体Rhizobium leguminosarum为研究这些动态提供了一个模型系统.
研究的目的:
- 为了研究塑造Rhizobium leguminosarum中的等离子体和染色体之间的基因分布的力量.
- 为了比较染色体基因与等离子体基因的健康效应.
- 为了测试有益基因在进化时间内从质粒移动到染色体的假设.
主要方法:
- 在染色体和等离子体DNA中对基因适应性影响的比较分析.
- 对植物殖民相关的不同生态的基因分布的评估.
- 检查不同年龄的等离子体 (最近与古代) 上的基因流行率.
主要成果:
- 与细菌染色体相比,有益的基因在等离子体上少得多.
- 强烈有益的基因,增强跨多个的健康状况,在染色体上得到丰富.
- 最近获得的等离子体比古代等离子体含有更多有益的基因,这表明基因转移.
结论:
- 进化过程有利于有益基因从质粒转移到细菌染色体.
- 细菌最初获得的等离子体可能是由有益的基因驱动的,但随着时间的推移,这种价值会受到侵蚀.
- 这些发现挑战了长期等离子体持久性模型,并突出了等离子体和染色体之间的动态相互作用.
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