Rediversification Following Ecotype Isolation Reveals Hidden Adaptive Potential.
Rediversification Following Ecotype Isolation Reveals Hidden Adaptive Potential.
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生态型隔离后的再多样化揭示了隐藏的适应潜力。
DOI：
10.1101/2023.05.03.539206
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Hallatschek,Oskar
中科院分区：
文献类型：
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作者：
Ascensao,JoaoA;Denk,Jonas;Lok,Kristen;Yu,QinQin;Wetmore,KellyM;Hallatschek,Oskar
微生物群落在生态过程中起着至关重要的作用，而微生物群落的多样性是其发挥作用的关键。然而，关于群落在生态型消除或灭绝后是否能够恢复生态多样性，以及重新多样化的群落与原始群落相比将如何变化，人们知之甚少。在这里，我们展示了简单的两个生态型群落。长期进化实验(LTEE)在分离其中一个生态型后，一致地重新多样化为两个生态型，通过负频率依赖选择共存。被3万多代进化时间隔开的群落以类似的方式重新多样化。重新多样化的生态型似乎与它所取代的生态型有许多共同的生长特征。然而，重新多样化的群落在与生态型共存机制相关的方式上也与原始群落不同--例如，在稳定期反应和生存方面。我们发现两个原始生态型之间的转录状态有很大的差异，而重新多样化的群落内部的差异相对较小，尽管重新多样化的群落表现出独特的差异表达模式。我们的结果表明，即使在一个最大限度地减少了只有两个品系的群落中，进化也可能为替代多样化过程留下空间。我们假设，在存在更多潜在生态位的许多物种的群落中，替代进化路径的存在可能更加明显，这突显了物种迁移等扰动在进化的生态群落中的重要作用。
Microbial communities play a critical role in ecological processes, and their diversity is key to their functioning. However, little is known about whether communities can regenerate ecological diversity following ecotype removal or extinction and how the rediversified communities would compare to the original ones. Here, we show that simple two-ecotype communities from theE. colilong-term evolution experiment (LTEE) consistently rediversified into two ecotypes following the isolation of one of the ecotypes, coexisting via negative frequency-dependent selection. Communities separated by more than 30,000 generations of evolutionary time rediversify in similar ways. The rediversified ecotype appears to share a number of growth traits with the ecotype it replaces. However, the rediversified community is also different from the original community in ways relevant to the mechanism of ecotype coexistence—for example, in stationary phase response and survival. We found substantial variation in the transcriptional states between the two original ecotypes, whereas the differences within the rediversified community were comparatively smaller, although the rediversified community showed unique patterns of differential expression. Our results suggest that evolution may leave room for alternative diversification processes even in a maximally reduced community of only two strains. We hypothesize that the presence of alternative evolutionary pathways may be even more pronounced in communities of many species where there are even more potential niches, highlighting an important role for perturbations, such as species removal, in evolving ecological communities.