University of Cologne, Biocenter, 50674 Cologne, Germany.
Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK.
Curr Biol. 2019 Nov 18;29(22):3899-3908.e3. doi: 10.1016/j.cub.2019.09.069. Epub 2019 Oct 31.
Rooting cells and pollen tubes-key adaptative innovations that evolved during the colonization and subsequent radiation of plants on land-expand by tip growth. Tip growth relies on a tight coordination between the protoplast growth and the synthesis/remodeling of the external cell wall. In root hairs and pollen tubes of the seed plant Arabidopsis thaliana, cell wall integrity (CWI) mechanisms monitor this coordination through the Malectin-like receptor kinases (MLRs), such as AtANXUR1 and AtFERONIA, that act upstream of the AtMARIS PTI1-like kinase. Here, we show that rhizoid growth in the early diverging plant, Marchantia polymorpha, is also controlled by an MLR and PTI1-like signaling module. Rhizoids, root hairs, and pollen tubes respond similarly to disruption of MLR and PTI1-like encoding genes. Thus, the MLR and PTI1-like signaling module that controls CWI during tip growth is conserved between M. polymorpha and A. thaliana, suggesting that it was active in the common ancestor of land plants.
扎根细胞和花粉管——植物在陆地上的定殖和随后的辐射过程中进化而来的关键适应性创新——通过尖端生长扩展。尖端生长依赖于原生质体生长和细胞壁的合成/重塑之间的紧密协调。在拟南芥的根毛和花粉管中，细胞壁完整性（CWI）机制通过类甘露糖结合凝集素受体激酶（MLRs），如 AtANXUR1 和 AtFERONIA，来监测这种协调，这些 MLRs 位于 AtMARIS PTI1 样激酶的上游。在这里，我们表明，早期分化的植物地钱的假根生长也受到 MLR 和 PTI1 样信号模块的控制。假根、根毛和花粉管对 MLR 和 PTI1 样编码基因的破坏反应相似。因此，控制尖端生长过程中 CWI 的 MLR 和 PTI1 样信号模块在地钱和拟南芥之间是保守的，这表明它在陆地植物的共同祖先中就已经活跃了。
