在许多植物物种中,冷处理或春化促进开花。春化诱导开花的机制已在拟南芥中得到广泛研究,但在豆科植物中仍然未知。FLC基因的直系同源物,拟南芥春化反应的主要调节剂,在对春化敏感的豆科植物中不存在或没有功能。然而,豆科植物整合基因FT和SOC1参与春化信号向分生组织身份基因的转变,包括PIM(AP1直向序列)。然而,这些基因对豆科植物中PIM激活的调控作用仍然难以捉摸。这里,我们提出了一个前馈调控基序的理论和数据驱动的分析,包括春化反应的FT基因和几个SOC1基因,它独立地激活PIM,从而介导花的转变。我们的理论模型表明,该调节基序中的多个调节分支有助于消除无义信号,并放大了来自上游调节器的有用信号。我们进一步开发并分析了野生型和fta1-1突变体在春化和非春化条件下在苜蓿中PIM激活的四个数据驱动模型。具有FTA1的模型通过三种中间活化剂提供直接活化和间接活化,SOC1a,SOC1b,和SOC1c,导致了最相关的PIM动态。在这个模型中,SOC1基因的调节输入之间的差异是非必需的。因此,在Trancatula模型中,SOC1a的累积作用,SOC1b,SOC1c受到青睐。总的来说,在这项研究中,我们首先提出了豆科植物春化诱导开花的计算机分析。随着新的实验数据的出现,可以通过其他监管部门来补充所考虑的春化网络主题。
In many plant species, flowering is promoted by the cold treatment or vernalization. The mechanism of vernalization-induced flowering has been extensively studied in Arabidopsis but remains largely unknown in legumes. The orthologs of the FLC gene, a major regulator of vernalization response in Arabidopsis, are absent or non-functional in the vernalization-sensitive legume species. Nevertheless, the legume integrator genes FT and SOC1 are involved in the transition of the vernalization signal to meristem identity genes, including PIM (AP1 ortholog). However, the regulatory contribution of these genes to PIM activation in legumes remains elusive. Here, we presented the theoretical and data-driven analyses of a feed-forward regulatory motif that includes a vernalization-responsive FT gene and several SOC1 genes, which independently activate PIM and thereby mediate floral transition. Our theoretical model showed that the multiple regulatory branches in this regulatory motif facilitated the elimination of no-sense signals and amplified useful signals from the upstream regulator. We further developed and analyzed four data-driven models of PIM activation in Medicago trancatula in vernalized and non-vernalized conditions in wild-type and fta1-1 mutants. The model with FTa1 providing both direct activation and indirect activation via three intermediate activators, SOC1a, SOC1b, and SOC1c, resulted in the most relevant PIM dynamics. In this model, the difference between regulatory inputs of SOC1 genes was nonessential. As a result, in the M. trancatula model, the cumulative action of SOC1a, SOC1b, and SOC1c was favored. Overall, in this study, we first presented the in silico analysis of vernalization-induced flowering in legumes. The considered vernalization network motif can be supplemented with additional regulatory branches as new experimental data become available.