The Cost of Being Big: Local Competition, Importance of Dispersal, and Experimental Evolution of Reversal to Unicellularity
The Cost of Being Big: Local Competition, Importance of Dispersal, and Experimental Evolution of Reversal to Unicellularity
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做大的代价：局部竞争、扩散的重要性以及逆转单细胞性的实验进化
DOI：
10.1086/700095
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
M. Travisano
中科院分区：
文献类型：
--
作者：
María Rebolleda;M. Travisano
多细胞性提供多种益处。尽管如此，单细胞是普遍存在的，并且已经有多个进化逆转为单细胞组织的案例。在这篇文章中，我们将探讨多细胞生物的一些代价，以及进化逆转为单细胞生物的可能性和动力学。我们假设，最近进化的多细胞生物体将面临一个高成本的空间结构化的环境中，因为更大的尺寸和增加的细胞密度的本地资源的竞争增加。为了验证这一假设，我们进行了竞争分析，计算机模拟和选择实验，使用分离的酿酒酵母，最近演变成多细胞。在充分混合的环境中，由于空间和资源获取的限制，多细胞分离物相对于其单细胞祖先具有较低的生长速率。在具有局部资源的结构化环境中，多细胞和单细胞分离物中的细胞以相似的速率生长。尽管相似的增长，更高的局部密度的细胞在多细胞群体导致竞争加剧和更高的健身成本在空间结构化的环境。在结构化的环境中，所有的多细胞分离株迅速演变成一个主要的单细胞生命周期，而在良好的混合环境逆转是渐进的。总之，这些结果表明，缺乏分散，导致更高的本地竞争，可能是早期多细胞形式进化的主要限制之一。
Multicellularity provides multiple benefits. Nonetheless, unicellularity is ubiquitous, and there have been multiple cases of evolutionary reversal to a unicellular organization. In this article, we explore some of the costs of multicellularity as well as the possibility and dynamics of evolutionary reversals to unicellularity. We hypothesize that recently evolved multicellular organisms would face a high cost of increased competition for local resources in spatially structured environments because of larger size and increased cell densities. To test this hypothesis we conducted competition assays, computer simulations, and selection experiments using isolates of Saccharomyces cerevisiae that recently evolved multicellularity. In well-mixed environments, multicellular isolates had lower growth rates relative to their unicellular ancestor because of limitations of space and resource acquisition. In structured environments with localized resources, cells in both multicellular and unicellular isolates grew at a similar rate. Despite similar growth, higher local density of cells in multicellular groups led to increased competition and higher fitness costs in spatially structured environments. In structured environments all of the multicellular isolates rapidly evolved a predominantly unicellular life cycle, while in well-mixed environments reversal was more gradual. Taken together, these results suggest that a lack of dispersal, leading to higher local competition, might have been one of the main constraints in the evolution of early multicellular forms.
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影响因子：
2.9
作者：
Zor, T;Seliger, Z
通讯作者：
Seliger, Z
影响因子：
2
作者：
Tarnita, Corina E.;Taubes, Clifford H.;Nowak, Martin A.
通讯作者：
Nowak, Martin A.
影响因子：
8.8
作者：
Harcombe WR;Riehl WJ;Dukovski I;Granger BR;Betts A;Lang AH;Bonilla G;Kar A;Leiby N;Mehta P;Marx CJ;Segrè D
通讯作者：
Segrè D
DOI：
10.1073/pnas.1421402112
发表时间：
2015-05
期刊：
Proceedings of the National Academy of Sciences
影响因子：
--
作者：
S. West;R. M. Fisher;A. Gardner;E. Kiers
通讯作者：
S. West;R. M. Fisher;A. Gardner;E. Kiers
影响因子：
16.8
作者：
Platt TG;Bever JD
通讯作者：
Bever JD