Kinmonth-Schultz Hannah A, MacEwen Melissa J S, Seaton Daniel D, Millar Andrew J, Imaizumi Takato, Kim Soo-Hyung
Department of Biology, University of Washington, Seattle, WA 98195, USA.
Present address: Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA.
In Silico Plants. 2019;1(1). doi: 10.1093/insilicoplants/diz006. Epub 2019 May 15.
We assessed mechanistic temperature influence on flowering by incorporating temperature-responsive flowering mechanisms across developmental age into an existing model. Temperature influences the leaf production rate as well as expression of (), a photoperiodic flowering regulator that is expressed in leaves. The Framework Model incorporated temperature influence on leaf growth but ignored the consequences of leaf growth on and direct temperature influence of expression. We measured production in differently aged leaves and modified the model, adding mechanistic temperature influence on transcription, and causing whole-plant to accumulate with leaf growth. Our simulations suggest that in long days, the developmental stage (leaf number) at which the reproductive transition occurs is influenced by day length and temperature through , while temperature influences the rate of leaf production and the time (in days) the transition occurs. Further, we demonstrate that is mainly produced in the first 10 leaves in the Columbia (Col-0) accession, and that accumulation alone cannot explain flowering in conditions in which flowering is delayed. Our simulations supported our hypotheses that: (i) temperature regulation of , accumulated with leaf growth, is a component of thermal time, and (ii) incorporating mechanistic temperature regulation of can improve model predictions when temperatures change over time.
我们通过将发育阶段的温度响应开花机制纳入现有模型，评估了温度对开花的机制性影响。温度影响叶片产生速率以及（）的表达，（）是一种在叶片中表达的光周期开花调节因子。框架模型纳入了温度对叶片生长的影响，但忽略了叶片生长对（）表达的影响以及温度对（）表达的直接影响。我们测量了不同年龄叶片中的（）产生量，并对模型进行了修改，增加了温度对（）转录的机制性影响，从而使全株（）随着叶片生长而积累。我们的模拟结果表明，在长日照条件下，生殖转变发生时的发育阶段（叶片数量）受日照长度和通过（）介导的温度影响，而温度影响叶片产生速率和转变发生的时间（天数）。此外，我们证明（）主要在哥伦比亚（Col-0）生态型的前10片叶子中产生，并且仅（）的积累不能解释开花延迟条件下的开花情况。我们的模拟结果支持了我们的假设：（i）随着叶片生长积累的（）的温度调节是热时间的一个组成部分，（ii）当温度随时间变化时，纳入（）的机制性温度调节可以改善模型预测。
