Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
Sainsbury Laboratory Cambridge University, Bateman Street, Cambridge, CB2 1LR, UK.
Cell Rep. 2021 Sep 14;36(11):109715. doi: 10.1016/j.celrep.2021.109715.
Many species have cuticular striations that play a range of roles, from pollinator attraction to surface wettability. In Hibiscus trionum, the striations span multiple cells at the base of the petal to form a pattern that produces a type of iridescence. It is postulated, using theoretical models, that the pattern of striations could result from mechanical instabilities. By combining the application of mechanical stress with high-resolution imaging, we demonstrate that the cuticle buckles to create a striated pattern. Through mechanical modeling and cryo-SEM fractures, we show that the cuticle behaves like a bilayer system with a stiff film on a compliant substrate. The pattern of buckling aligns with the direction of the stress to create a larger-scale pattern. Our findings contribute to the understanding of the formation of tissue-wide patterns in living organisms.
许多物种的表皮具有条纹结构，这些条纹在吸引传粉者和改变表面润湿性等方面发挥着一系列作用。在芙蓉花中，这些条纹跨越花瓣基部的多个细胞，形成一种产生虹彩效果的图案。通过理论模型推测，这种条纹图案可能是由机械不稳定性引起的。通过结合机械应力的施加和高分辨率成像，我们证明了表皮会弯曲形成条纹图案。通过机械建模和冷冻扫描电子显微镜（cryo-SEM）断裂实验，我们表明表皮的行为类似于具有刚性薄膜和柔软基底的双层系统。弯曲的模式与应力的方向一致，从而形成更大尺度的图案。我们的研究结果有助于理解生物体中组织范围图案的形成机制。
