通过电子断层成像，研究人员绘制了细胞板窗孔到质外体的过渡。研究人员发现内质网（ER）在窗孔之间连接子细胞，随着细胞板的成熟，窗孔收缩，导致质膜（PM）围绕收缩的ER管道成形。ER的存在阻止窗孔融合，形成质外体，而其缺失则导致关闭。ER-PM蛋白结合物MCTP3、MCTP4和MCTP6在窗孔收缩期间进一步稳定新生的质外体。在拟南芥中进行的基因缺失实验减少了质外体的形成。该研究揭示了植物如何通过不完全分裂促进细胞间的交流。
据悉，与传统的细胞分裂模型不同，植物细胞通过不完全分裂生成子细胞之间的质外体沟通桥。虽然这对植物的多细胞性至关重要，但导致桥接稳定而不是断裂的分子事件仍不清楚。
附：英文原文
Title: Plant plasmodesmata bridges form through ER-dependent incomplete cytokinesis
Author: Ziqiang P. Li, Hortense Moreau, Jules D. Petit, Tatiana S. Moraes, Marija Smokvarska, Jessica Pérez-Sancho, Melina Petrel, Fanny Decoeur, Lysiane Brocard, Clément Chambaud, Magali S. Grison, Andrea Paterlini, Marie Glavier, Lucie Hoornaert, Amit S. Joshi, Etienne Gontier, William A. Prinz, Yvon Jaillais, Antoine Taly, Felix Campelo, Marie-Cécile Caillaud, Emmanuelle M. Bayer
Issue&Volume: 2024-11-01
Abstract: Diverging from conventional cell division models, plant cells undergo incomplete division to generate plasmodesmata communication bridges between daughter cells. Although fundamental for plant multicellularity, the molecular events leading to bridge stabilization, as opposed to severing, remain unknown. Using electron tomography, we mapped the transition from cell plate fenestrae to plasmodesmata. We show that the endoplasmic reticulum (ER) connects daughter cells across fenestrae, and as the cell plate matures, fenestrae contract, causing the plasma membrane (PM) to mold around constricted ER tubes. The ER’s presence prevents fenestrae fusion, forming plasmodesmata, whereas its absence results in closure. The ER-PM protein tethers MCTP3, MCTP4, and MCTP6 further stabilize nascent plasmodesmata during fenestrae contraction. Genetic deletion in Arabidopsis reduces plasmodesmata formation. Our findings reveal how plants undergo incomplete division to promote intercellular communication.
DOI: adn4630
Source: https://www.science.org/doi/10.1126/science.adn4630