Inflorescence architecture in cereal crops directly impacts yield potential through regulation of seed number and harvesting ability. Extensive architectural diversity found in inflorescences of grass species is due to spatial and temporal activity and determinacy of meristems, which control the number and arrangement of branches and flowers, and underlie plasticity. Timing of the floral transition is also intimately associated with inflorescence development and architecture, yet little is known about the intersecting pathways and how they are rewired during development. Here, we show that a single mutation in a gene encoding an AP1 A-class MADS-box transcription factor significantly delays flowering time and disrupts multiple levels of meristem determinacy in panicles of the C₄ model panicoid grass, Setaria viridis. Previous reports of A-class genes in cereals have revealed extensive functional redundancy, and in panicoid grasses, no associated inflorescence phenotypes have been described. In S. viridis, perturbation of SvFul2, both through chemical mutagenesis and CRISPR/Cas9-based gene editing, converted a normally determinate inflorescence habit to an indeterminate one, and also repressed determinacy in axillary branch and floral meristems. Our analysis of gene networks connected to disruption of SvFul2 identified regulatory hubs at the intersect of floral transition and inflorescence determinacy, providing insights into the optimization of cereal crop architecture.

中文翻译：

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SvFUL2是一种A类MADS-box转录因子，对于模型Panicoid谷物Setaria viridis中的花序确定是必需的

谷物作物的花序结构通过调节种子数量和收获能力直接影响单产潜力。在草种的花序中发现的广泛的建筑多样性是由于分生组织的时空活动和确定性而决定的，分生组织控制着枝和花的数量和排列，并且是可塑性的基础。花序过渡的时间也与花序的发育和结构密切相关，但对相交的途径以及它们在发育过程中如何重新连接的了解甚少。在这里，我们表明，编码AP1 A类MADS-box转录因子的基因中的单个突变会显着延迟开花时间，并破坏C ₄模型panicoid草的穗中分生组织的多个水平，狗尾草。谷物中A类基因的先前报道显示了广泛的功能冗余，在圆锥形草中，没有相关的花序表型被描述。在S. viridis中，通过化学诱变和基于CRISPR / Cas9的基因编辑对SvFul2的扰动，将通常确定的花序习性转变为不确定的习惯，并且还抑制了腋生分枝和花分生组织的确定性。我们对与SvFul2破坏有关的基因网络的分析确定了在花期过渡和花序确定性相交处的调控枢纽，从而为谷物作物结构的优化提供了见识。