A Growth-Based Framework for Leaf Shape Development and Diversity
A Growth-Based Framework for Leaf Shape Development and Diversity
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DOI：
10.1016/j.cell.2019.05.011
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发表时间：
2019-05-30
期刊：
影响因子：
64.5
通讯作者：
Tsiantis, Miltos
中科院分区：
文献类型：
--
作者：
Kierzkowski, Daniel;Runions, Adam;Tsiantis, Miltos
基因如何改变细胞生长从而产生形态多样性？我们研究了两种叶片形状不同的相关植物：拟南芥（叶片形状简单）和小豆豆（叶片形状复杂，有小叶）。我们使用实时成像、建模和遗传学将这些器官水平的差异解构为细胞水平的成分：生长量、方向和分化。我们发现叶片形状取决于两种生长模式的相互作用：反映分化的保守的全器官生长模式；还有一种局部的、定向的模式，它包括沿叶子边缘生长焦点的图案。形状多样性源于两个同源盒基因对这些生长模式的不同影响：相对于边缘图案，SHOOTMERISTEMLESS扩大了器官范围的生长，使小叶出现，而降低复杂性抑制了小叶周围的局部生长，强调了图案造成的形状差异。我们通过重建拟南芥中毛毛草叶片形态的关键特征来证明我们的发现的预测性。
How do genes modify cellular growth to create morphological diversity? We study this problem in two related plants with differently shaped leaves: Arabidopsis thaliana (simple leaf shape) and Cardamine hirsute (complex shape with leaflets). We use live imaging, modeling, and genetics to deconstruct these organ-level differences into their cell-level constituents: growth amount, direction, and differentiation. We show that leaf shape depends on the interplay of two growth modes: a conserved organ-wide growth mode that reflects differentiation; and a local, directional mode that involves the patterning of growth foci along the leaf edge. Shape diversity results from the distinct effects of two homeobox genes on these growth modes: SHOOTMERISTEMLESS broadens organ-wide growth relative to edge-patterning, enabling leaflet emergence, while REDUCED COMPLEXITY inhibits growth locally around emerging leaflets, accentuating shape differences created by patterning. We demonstrate the predictivity of our findings by reconstructing key features of C. hirsuta leaf morphology in A. thaliana.