PDF(Pubmed)
Abstract：
OBJECTIVE: Whole-genome duplication (WGD, polyploidization) has been identified as a driver of genetic and phenotypic novelty, having pervasive consequences for the evolution of lineages. While polyploids are widespread, especially among plants, the long-term establishment of polyploids is exceedingly rare. Genome doubling commonly results in increased cell sizes and metabolic expenses, which may be sufficient to modulate polyploid establishment in environments where their diploid ancestors thrive.
METHODS: We developed a mechanistic simulation model of photosynthetic individuals to test whether changes in size and metabolic efficiency allow autopolyploids to coexist with, or even invade, ancestral diploid populations. Central to the model is metabolic efficiency, which determines how energy obtained from size-dependent photosynthetic production is allocated to basal metabolism as opposed to somatic and reproductive growth. We expected neopolyploids to establish successfully if they have equal or higher metabolic efficiency as diploids or to adapt their life history to offset metabolic inefficiency.
RESULTS: Polyploid invasion was observed across a wide range of metabolic efficiency differences between polyploids and diploids. Polyploids became established in diploid populations even when they had a lower metabolic efficiency, which was facilitated by recurrent formation. Competition for nutrients is a major driver of population dynamics in this model. Perenniality did not qualitatively affect the relative metabolic efficiency from which tetraploids tended to establish.
CONCLUSIONS: Feedback between size-dependent metabolism and energy allocation generated size and age differences between plants with different ploidies. We demonstrated that even small changes in metabolic efficiency are sufficient for the establishment of polyploids.
METHODS: We developed a mechanistic simulation model of photosynthetic individuals to test whether changes in size and metabolic efficiency allow autopolyploids to coexist with, or even invade, ancestral diploid populations. Central to the model is metabolic efficiency, which determines how energy obtained from size-dependent photosynthetic production is allocated to basal metabolism as opposed to somatic and reproductive growth. We expected neopolyploids to establish successfully if they have equal or higher metabolic efficiency as diploids or to adapt their life history to offset metabolic inefficiency.
RESULTS: Polyploid invasion was observed across a wide range of metabolic efficiency differences between polyploids and diploids. Polyploids became established in diploid populations even when they had a lower metabolic efficiency, which was facilitated by recurrent formation. Competition for nutrients is a major driver of population dynamics in this model. Perenniality did not qualitatively affect the relative metabolic efficiency from which tetraploids tended to establish.
CONCLUSIONS: Feedback between size-dependent metabolism and energy allocation generated size and age differences between plants with different ploidies. We demonstrated that even small changes in metabolic efficiency are sufficient for the establishment of polyploids.
摘要：
目标：全基因组复制（WGD，多倍体化)已被确定为遗传和表型新颖性的驱动因素，对谱系的进化有着普遍的影响。虽然多倍体普遍存在，尤其是在植物中，多倍体的长期建立极为罕见。基因组加倍通常会导致细胞大小和代谢费用增加，这可能足以在其二倍体祖先茁壮成长的环境中调节多倍体的建立。
方法：我们开发了光合个体的机理模拟模型，以测试大小和代谢效率的变化是否允许自身多倍体与，甚至入侵，祖先二倍体种群。模型的核心是代谢效率，这决定了从大小依赖性光合生产中获得的能量如何分配给基础代谢，而不是体细胞和生殖生长。我们预计，如果新多倍体具有与二倍体相同或更高的代谢效率，或者适应其生活史以抵消代谢效率低下，它们将成功建立。
结果：在多倍体和二倍体之间的广泛代谢效率差异中观察到多倍体入侵。多倍体在二倍体种群中建立，即使它们的代谢效率较低，这是通过反复形成促进的。在此模型中，营养竞争是人口动态的主要驱动因素。多年性不会定性地影响四倍体倾向于建立的相对代谢效率。
结论：大小依赖性代谢和能量分配之间的反馈产生了具有不同倍性的植物之间的大小和年龄差异。我们证明，即使代谢效率的微小变化也足以建立多倍体。
方法：我们开发了光合个体的机理模拟模型，以测试大小和代谢效率的变化是否允许自身多倍体与，甚至入侵，祖先二倍体种群。模型的核心是代谢效率，这决定了从大小依赖性光合生产中获得的能量如何分配给基础代谢，而不是体细胞和生殖生长。我们预计，如果新多倍体具有与二倍体相同或更高的代谢效率，或者适应其生活史以抵消代谢效率低下，它们将成功建立。
结果：在多倍体和二倍体之间的广泛代谢效率差异中观察到多倍体入侵。多倍体在二倍体种群中建立，即使它们的代谢效率较低，这是通过反复形成促进的。在此模型中，营养竞争是人口动态的主要驱动因素。多年性不会定性地影响四倍体倾向于建立的相对代谢效率。
结论：大小依赖性代谢和能量分配之间的反馈产生了具有不同倍性的植物之间的大小和年龄差异。我们证明，即使代谢效率的微小变化也足以建立多倍体。
