红豆草根瘤侵染细胞核在细胞凋亡中的超微结构变化

用透射电镜观察红豆草根瘤侵染细胞核在细胞凋亡过程中的超微结构,以探讨红豆草根瘤侵染细胞核在发育过程中的超微结构变化及其与细胞凋亡的关系.结果表明,红豆草根瘤侵染细胞核的超微结构随细胞发育程度不同而不同.在幼龄侵染细胞中,细胞核体积较大,近似圆形.在即将成熟和成熟的侵染细胞中,细胞核膜有内陷现象,其核仁常具有核仁泡和核仁联合体.在早期凋亡的侵染细胞中,细胞核体积减小,形状变得不规则,核膜出现大量内陷,在其表面形成许多大的突起和深的沟槽,有时还有内质网、线粒体、小液泡和细菌等位于核膜的内陷处,而且核仁也开始裂解.在后期凋亡的侵染细胞中,除细菌解体外,还出现核仁消失,核膜破裂,核质外流,并在细胞质中形成一些电子密度很高,无一定形状的团块状物质.

Ultrastructural Changes Of Infected Cell Nuclei during Cell Apoptosis in Onobrychis viciaefolia Root Nodules

Ultrastructures of infected cell nuclei were studied by using transmission electron microscopy during the cell apoptosis in Onobrychis viciaefolia root nodules.The results showed that the ultrastructures were different in different development stages.The nuclei of young infected cells were larger in size,approximated round-shaped.In maturing and matured infected cells,the invaginations had occurred on the nuclear envelope,the nucleoli often possessed a large nucleolus vacuole and a nucleolus-associated body.At early stage of the infected cell apoptosis,the nuclei became smaller in size and very irregular in shape.A large quantity of invaginations was observed on nuclear envelopes,forming many large protrusions and invaginations.Endoplasmic reticulum,mitochondria,vesicles or bacteria were found in the nuclear envelope invaginations and the nucleoli in these infected cells initiated split.At the late stage of the infected cell apoptosis,the bacteroids initiated disintegration and the nucleoli disappeared,the nuclear envelopes broke,the nuclear substance flowed out and some remainders of nuclei,which were high in electron-density and unfixed in shape,in the infected cell cytoplasm formed.It was discussed that the ultrastructural changes of the infected cell nuclei of Onobrychis viciaefolia root nodules during the development and its relation to cell apoptosis in this paper.