Colorful flower patterns are key signals to attract pollinators. To produce such motifs, plants specify boundaries dividing petals into subdomains where cells develop distinctive pigmentations, shapes, and textures. While some transcription factors and biosynthetic pathways behind these characteristics are well studied, the upstream processes restricting their activities to specific petal regions remain enigmatic. Here, we unveil that the petal surface of Hibiscus trionum , an emerging model featuring a bullseye on its corolla, is prepatterned as the bullseye boundary position is specified long before it becomes visible. Using a computational model, we explore how pattern proportions are maintained while petals experience a 100-fold size increase. Exploiting transgenic lines and natural variants, we show that plants can regulate boundary position during the prepatterning phase or modulate growth on either side of this boundary later in development to vary bullseye proportions. Such modifications are functionally relevant, as buff-tailed bumblebees can reliably identify food sources based on bullseye size and prefer certain pattern proportions.

中文翻译：

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芙蓉靶心揭示了控制影响植物与传粉媒介相互作用的花瓣图案比例的机制


五颜六色的花朵图案是吸引传粉者的关键信号。为了产生这样的图案，植物指定了边界，将花瓣划分为多个子结构域，细胞在其中发展出独特的色素沉着、形状和纹理。虽然这些特征背后的一些转录因子和生物合成途径得到了很好的研究，但将其活动限制在特定花瓣区域的上游过程仍然是个谜。在这里，我们揭示了 Hibiscus trionum 的花瓣表面，这是一种新兴的模型，其花冠上有一个靶心，它是预先定型的，因为靶心边界位置在它变得可见之前很久就已经指定。使用计算模型，我们探讨了在花瓣大小增加 100 倍时如何保持图案比例。利用转基因品系和自然变体，我们表明植物可以在预图案阶段调节边界位置，或在发育后期调节该边界两侧的生长以改变靶心比例。这种修饰在功能上是相关的，因为棕尾大黄蜂可以根据靶心大小可靠地识别食物来源，并且更喜欢某些模式比例。