Department of Horticultural Sciences, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran.
Protoplasma. 2023 Mar;260(2):419-435. doi: 10.1007/s00709-022-01788-5. Epub 2022 Jun 27.
One of the classes of the plant developmental programmed cell death (PCD) is vacuolar cell death or autolysis. The results of the transmission electron microscope (TEM) studies indicated that this type of PCD occurs during the petal senescence of Antirrhinum majus "Legend White" flowers. The major hallmarks of the process related to the ultrastructure of the cells involved chloroplast degradation, vacuolation, chromatin condensation, cell wall swelling, degradation of Golgi apparatus, protoplasmic shrinkage, degradation of the endoplasmic reticulum, nuclear fragmentation, rupture of tonoplast, and plasma membrane. Macroautophagy and microautophagy processes were also clearly observed during vacuole formation. As in yeasts, in the present study, Golgi apparatus became autophagosome-like structures during degradation that had autophagy activity and then disappeared. Our results revealed a type of selective microautophagy, piecemeal microautophagy of the nucleus (PMN), in nuclear degradation during PCD of petals that has not previously been reported in plants. Moreover, vesicular structures, such as paramural and multilamellar bodies, were observed in some stages.
植物发育程序性细胞死亡（PCD）的一类是液泡细胞死亡或自溶。透射电子显微镜（TEM）研究的结果表明，这种类型的 PCD 发生在 Antirrhinum majus“Legend White”花瓣衰老过程中。与涉及细胞的超微结构相关的过程的主要特征是质体降解、液泡化、染色质浓缩、细胞壁肿胀、高尔基体降解、原生质收缩、内质网降解、核碎裂、液泡破裂和质膜破裂。在液泡形成过程中还清楚地观察到巨自噬和微自噬过程。与酵母一样，在本研究中，高尔基体在降解过程中变成具有自噬活性然后消失的自噬体样结构。我们的研究结果揭示了一种选择性微自噬，即花瓣 PCD 中核的片段微自噬（PMN），这在植物中以前没有报道过。此外，在某些阶段还观察到囊泡结构，如壁旁和多层体。
