The Scaling of Genome Size and Cell Size Limits Maximum Rates of Photosynthesis with Implications for Ecological Strategies
The Scaling of Genome Size and Cell Size Limits Maximum Rates of Photosynthesis with Implications for Ecological Strategies
复制标题
DOI：
10.1086/706186
复制
发表时间：
2020-01-01
影响因子：
2.3
通讯作者：
Simonin, Kevin A.
中科院分区：
文献类型：
--
作者：
Roddy, Adam B.;Theroux-Rancourt, Guillaume;Simonin, Kevin A.
植物生态学的一个核心挑战是确定植物功能变异的主轴，并对适应性产生直接影响。植物适应性的三个主要组成部分（生长，存活和繁殖）的核心是CO2代谢转化为碳的速率，可以分配给各种结构和功能。在这里，我们（1）认为，每单位叶面积的光合作用的最大速率的主要限制是细胞的大小和包装密度和（2）表明，基因组大小的变化是一个强大的预测细胞大小，包装密度，光合作用的最大速率在陆生维管植物。不管与基因组大小变化相关的基因含量如何，封装基因组的简单生物物理约束限定了细胞大小的下限和细胞堆积密度的上限，以及可能的细胞大小和密度的范围。因此，基因组的大小，作为一个一阶约束的碳增益，并预计将定义的上限分配到生长，繁殖和防御。因此，基因组大小对代谢的强烈影响对植物地理学和植物生态学的其他理论具有广泛的意义，并表明对代谢的选择可能在基因组大小进化中起作用。
A central challenge in plant ecology is to define the major axes of plant functional variation with direct consequences for fitness. Central to the three main components of plant fitness (growth, survival, and reproduction) is the rate of metabolic conversion of CO2 into carbon that can be allocated to various structures and functions. Here we (1) argue that a primary constraint on the maximum rate of photosynthesis per unit leaf area is the size and packing density of cells and (2) show that variation in genome size is a strong predictor of cell sizes, packing densities, and the maximum rate of photosynthesis across terrestrial vascular plants. Regardless of the genic content associated with variation in genome size, the simple biophysical constraints of encapsulating the genome define the lower limit of cell size and the upper limit of cell packing densities, as well as the range of possible cell sizes and densities. Genome size, therefore, acts as a first-order constraint on carbon gain and is predicted to define the upper limits of allocation to growth, reproduction, and defense. The strong effects of genome size on metabolism, therefore, have broad implications for plant biogeography and for other theories of plant ecology and suggest that selection on metabolism may have a role in genome size evolution.