植物细胞核基质(Nuclear Matrix)的形态结构及其NuMA蛋白成分的研究

STUDY ON MORPHOLOGICAL STRUCTURE AND PROTEIN COMPONENT NuMA OF NUCLEAR MATRIX IN PLANT CELLS

应用细胞选择性抽提并结合DGD包埋去包埋剂电镜技术对植物细胞核基质的形态结构进行了观察。结果显示胡萝卜悬浮培养细胞、银杏花粉细胞和精子细胞的细胞核内存在一个非染色质性的纤维蛋白网络体系。免疫荧光染色结果说明植物细胞核基质中含有与动物NuMA多抗交叉反应的多肽。免疫印迹反应显示胡萝卜悬浮培养细胞核基质蛋白与NuMA蛋白多抗的阳性反应条带为74KD和76 KD;银杏花粉细胞只有78 KD一条阳性带。以动物核基质NuMA蛋白保守杆状区的cDNA片段作为探针,与白菜子叶总DNA进行Southern杂交的结果表明植物细胞基因组中含有动物NuMA蛋白cDNA的同源序列。

Using selective extraction and diethy-lene glycol distearate (DGD) embedment and embedment-free electron microscopy, the well-organized nuclear matrix networks were observed in carrot suspension cells, ginkgo pollen cells and sperm cells.Immunofluorescence staining revealed the existence of NuMA protein-like components in carrot suspension cells and ginkgo pollen cells.Western blotting showed that, in carrot cells, there were two positive crossreaction bands, M. W. 74 KDand 76 KD, recognized by polyclonal antibodies against animal NuMA; and in ginkgo pollen cells, only one, 78 KD. Southern blot showed that plant cells had the homologous sequences with that of animal NuMA cDNA.Our data verified that there indeed existed nuclear matrix in plant cells. The data implied that plant NuMA proteins shared some homology with the correspondent components in animal cells and may be conserved during evolution.