Rebocho Alexandra B, Southam Paul, Kennaway J Richard, Bangham J Andrew, Coen Enrico
Department of Cell and Developmental Biology, John Innes Centre, Norwich, England.
School of Computational Sciences, University of East Anglia, Norwich, England.
Elife. 2017 Feb 7;6:e20156. doi: 10.7554/eLife.20156.
Out-of-plane tissue deformations are key morphogenetic events during plant and animal development that generate 3D shapes, such as flowers or limbs. However, the mechanisms by which spatiotemporal patterns of gene expression modify cellular behaviours to generate such deformations remain to be established. We use the Snapdragon flower as a model system to address this problem. Combining cellular analysis with tissue-level modelling, we show that an orthogonal pattern of growth orientations plays a key role in generating out-of-plane deformations. This growth pattern is most likely oriented by a polarity field, highlighted by PIN1 protein localisation, and is modulated by dorsoventral gene activity. The orthogonal growth pattern interacts with other patterns of differential growth to create tissue conflicts that shape the flower. Similar shape changes can be generated by contraction as well as growth, suggesting tissue conflict resolution provides a flexible morphogenetic mechanism for generating shape diversity in plants and animals.
平面外组织变形是动植物发育过程中的关键形态发生事件，可生成三维形状，如花朵或肢体。然而，基因表达的时空模式改变细胞行为以产生此类变形的机制仍有待确定。我们以金鱼草花为模型系统来解决这个问题。通过将细胞分析与组织水平建模相结合，我们表明生长方向的正交模式在产生平面外变形中起关键作用。这种生长模式很可能由极性场定向，PIN1蛋白定位突出了该极性场，并且受背腹基因活性的调节。正交生长模式与其他差异生长模式相互作用，产生塑造花朵的组织冲突。收缩以及生长都可产生类似的形状变化，这表明组织冲突解决为动植物中产生形状多样性提供了一种灵活的形态发生机制。
