Sperm cells in pollen tubes ofNicotians tabacum L.: three-dimensional reconstruction, cytoplasmic diminution, and quantitative cytology
Sperm cells in pollen tubes ofNicotians tabacum L.: three-dimensional reconstruction, cytoplasmic diminution, and quantitative cytology
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烟草花粉管中精子细胞的三维重建、细胞质缩减和定量细胞学
DOI：
10.1007/bf01666263
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发表时间：
1992
期刊：
影响因子：
2.9
通讯作者：
S. Russell
中科院分区：
文献类型：
--
作者：
H. S. Yu;H. S. Yu;Shi;S. Russell
采用透射电镜、计算机辅助连续切片重建和细胞学定量方法，对半活体授粉后18 h的烟草精细胞和营养核（雄性生殖单位）的组织结构进行了观察。基于对9对重构精子的11个细胞参数的测量，两种细胞之间没有统计学上的显著差异。其特征是与营养核表面有物理联系的带状细胞质延伸。细胞核与精子横壁相邻，精子细胞器分布于细胞核与外壁之间。细胞呈锥形，两极有细胞质区，近横壁有深轴向内陷。这种细胞的细胞核位于中心，细胞器基本上呈极性分布。我们观察到三种细胞质减少的机制，它们似乎对细胞质体积和细胞器的损失起着积极的作用：(1)Sua中去核的细胞质体产生；(2) Svn细胞质突起尖端出现囊泡；(3) svna和Sua的周质中均有囊泡体积聚。
The organization of the sperm cells and vegetative nucleus (male germ unit) ofNicotiana tabacumwas examined 18 h after semivivo pollination using transmission electron microscopy, computerassisted serial section reconstruction and quantitative cytology. Based on a measurement of 11 cellular parameters in nine reconstructed sperm cell pairs, there are no statistically significant differences between the two cells. The Svnis characterized by a strapshaped cytoplasmic extension that is physically associated with the surface of the vegetative nucleus. The nucleus is located adjacent to the sperm crosswall, with sperm organelles being distributed between the nucleus and the extension. The Suais a tapered cell with cytoplasmic areas at both poles and deep axial invaginations near the crosswall. This cell has a centrally-located nucleus and a largely polar distribution of organelles. Three mechanisms for cytoplasmic diminution were observed that appear to contribute actively to the loss of cytoplasmic volume and organelles: (1) enucleated cytoplasmic body production in the Sua; (2) vesiculation at the tip of the cytoplasmic projection of the Svn; and (3) vesicle-containing body accumulation in the periplasm of both the Svnand Sua.