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小麦淀粉胚乳在发育过程中经历程序性细胞死亡(PCD)。小麦淀粉胚乳的DNA在发育的特定阶段呈现梯状电泳条带,用乙烯处理使DNA片段化发生的时间提前,而用ABA处理虽然不能推迟DNA片段化的发生时间,但能减弱DNA片段化的程度。小麦淀粉胚乳细胞在PCD过程中出现某些动植物细胞凋亡的共同的结构变化特征,但也有一些独特的结构变化。如染色质凝聚后仅少数染色质块发生趋边化;细胞核在PCD过程中最先开始衰退,细胞核解体时胞质中有丰富的细胞器,细胞核解体后细胞并未死亡,在胞质中仍在合成和积累淀粉和储藏蛋白,直到细胞被 淀粉充满,细胞才死亡;不形成凋亡小体,死亡的淀粉胚乳细胞成为营养物质的储藏库。因此小麦淀粉胚乳细胞的PCD是一种特殊形式的PCD。
Wheat starch endosperm undergoes programmed cell death (PCD) during development. The DNA of wheat starch endosperm showed ladder electrophoresis bands at specific stages of development. The treatment with ethylene advanced the DNA fragmentation, while the treatment with ABA did not delay the onset of DNA fragmentation but attenuated DNA fragmentation degree. Wheat starchy endosperm cells show some common structural changes of apoptosis in animal and plant cells during PCD, but there are also some unique structural changes. Such as chromatin condensation only a few chondriosomes tend to occur; nucleus in the process of PCD began the first recession, cell nucleus when the cytoplasm is rich in organelles, the nucleus after disintegration of the cells did not die in the cytoplasm is still The synthesis and accumulation of starch and storage protein until the cells are filled with starch, the cells died; do not form apoptotic bodies, dead starchy endosperm cells become a reservoir of nutrients. Therefore, the PCD of wheat starchy endosperm cells is a special form of PCD.