塑性和组级调节的进化 细胞分化在volvocine藻类的调节
Dinah R Davison1,2, Aurora M Nedelcu3, Onyi De Andre Eneji4
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA.
Proceedings. Biological sciences
|March 19, 2025
概括
藻中的可塑性允许体状细胞在压力下发育. 这提供了对群体级特征,如体质分化,如何在多细胞生物体中演变的见解.
科学领域:
- 进化生物学是进化的生物学.
- 发育生物学是发展生物学.
- 藻类生物学 藻类生物学
背景情况:
- 多细胞性的进化涉及选择单位从单细胞转向多细胞群的转变.
- 这种过渡需要组级特征的发展,如体质分化,但基本过程尚未得到充分理解.
研究的目的:
- 调查表型可塑性在藻体差异化演变中的作用.
- 探索是否包括体状细胞的塑性发展的中间步骤先于义务体的进化.
主要方法:
- 在Eudorina elegans的殖民地中诱导环境压力 (冷冲击).
- 观察和描述体状细胞在应对压力的过程中的发育.
- 分析应激殖民地后代体状细胞发育的遗传.
主要成果:
- *Eudorina elegans*,以前被认为是不分化的,在寒冷冲击条件下表现出体状细胞的塑性发育.
- 这些诱导的体状细胞类似于在更复杂的卷类物种中发现的义务体.
- 身体类细胞分化最初作为细胞水平的特征发生,导致殖民地表型作为交叉水平的副产品.
- 处于压力状态的殖民地后代也会发展出体状细胞,这表明在群体发育过程中的调节以及真正的群体级特征.
结论:
- 现型可塑性可以促进群体级特征的起源,例如强制体格差异化.
- 由细胞水平可塑性产生的跨层次副产品,可以作为组级特征进化的中间阶段.
- 这项研究为了解早期多细胞生命中的分工演变提供了一个模型.
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